18.3: Calculating electric potential from charge distributions
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In this section, we give two examples of determining the electric potential for different charge distributions. We have two methods that we can use to calculate the electric potential from a distribution of charges:
- Model the charge distribution as the sum of infinitesimal point charges, \(dq\) , and add together the electric potentials, \(dV\) , from all charges, \(dq\) . This requires that one choose \(0\text{V}\) to be located at infinity, so that the \(dV\) are all relative to the same point.
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Calculate the electric field (either as a integral or from Gauss’ Law), and use:
\[\begin{aligned} \Delta V &=V(\vec r_B)-V(\vec r_A)=-\int_A^B \vec E\cdot d\vec r\end{aligned}\]
The first method is similar to how we calculated the electric field for distributed charges in chapter 16, but with the simplification that we only need to sum scalars instead of vectors. The second method was already introduced in this chapter.
Example \(\PageIndex{1}\)
A ring of radius \(R\) carries a total charge \(+Q\) . Determine the electric potential a distance \(a\) from the center of the ring, along the axis of symmetry of the ring. Assume that zero electric potential is defined at infinity.
Solution
Figure \(\PageIndex{1}\) shows a diagram of the ring, and our choice of infinitesimal charge, \(dq\) .
In order to calculate the electric potential at point, \(P\) , with \(0\text{V}\) defined to be at infinity, we first calculate the infinitesimal potential at \(P\) from the infinitesimal point charge, \(dq\) :
\[\begin{aligned} dV=k\frac{dq}{r}\end{aligned}\]
The total electric potential is then the sum (integral) of these potentials:
\[\begin{aligned} V=\int dV=\int k\frac{dq}{r} = \frac{k}{r}\int dq=k\frac{Q}{r}=k\frac{Q}{\sqrt{a^2+R^2}}\end{aligned}\]
where we recognized that \(k\) and \(r\) are the same for each \(dq\) , so that they could factor out of the integral. \(\int dq=Q\) is then just the sum of the infinitesimal charges, which must add to the charge of the ring.
Discussion
In this example, we determined the electric potential, relative to infinity, a distance \(a\) from the center of a charge ring, along its axis of symmetry. We modeled the ring as being made of many infinitesimal point charges, and summed together the infinitesimal electric potentials from those charges relative to infinity. This was much simpler than determining the electric field, since electric potential is a scalar and we do not need to consider how the components from different \(dq\) along the ring will cancel.
Example \(\PageIndex{2}\)
A long, thin, straight wire carries uniform charge per unit length, \(\lambda\) . The electric potential difference between points located at distances \(r_B=2\text{cm}\) and \(r_A=1\text{cm}\) from the wire is found to be \(V(r_B)-V(r_A)=-100\text{V}\) . What is the linear charge density on wire, \(\lambda\) ?
Solution
In this case, we can use Gauss’ Law to determine the electric field at a certain distance from the wire. From that, we can calculate the electric potential difference between any two points near the wire, and thus the charge density on the wire.
By using a cylindrical surface of length, \(L\) , and radius, \(r\) , we can use Gauss’ Law to determine the field at a distance, \(r\) , from the wire:
\[\begin{aligned} \oint \vec E\cdot d\vec A&=\frac{Q^{enc}}{\epsilon_0}\\[4pt] 2\pi r L E&= \frac{\lambda L}{\epsilon_0}\\[4pt] \therefore \vec E(r)&=\frac{\lambda}{2\pi\epsilon_0 r}\hat r\end{aligned}\]
Using the electric field, we can calculate the potential difference between two points that are at distances, \(r_A\) and \(r_B\) , from the wire:
\[\begin{aligned} \Delta V &=V(r_B)-V(r_A)=-\int_{r_A}^{r_B} \vec E\cdot d\vec r\\[4pt] &=-\int_{r_A}^{r_B} \left( \frac{\lambda}{2\pi\epsilon_0 r}\hat r \right)\cdot d\vec r=-\frac{\lambda}{2\pi\epsilon_0}\int_{r_A}^{r_B} \frac{1}{r}\hat r \cdot d\vec r=-\frac{\lambda}{2\pi\epsilon_0}\int_{r_A}^{r_B} \frac{1}{r}dr\\[4pt] &=-\frac{\lambda}{2\pi\epsilon_0}\left[|\ln(r)|\right]_{r_A}^{r_B} = -\frac{\lambda}{2\pi\epsilon_0}\ln\left(\frac{r_B}{r_A}\right)\\[4pt] \therefore\Delta V &=\frac{\lambda}{2\pi\epsilon_0}\ln\left(\frac{r_A}{r_B}\right)\end{aligned}\]
where, in the second last line, we removed the absolute value from the logarithm, since \(r_A<r_B\) , and in the last line, we removed the minus sign by inverting the argument of the logarithm. Since we know the potential difference, \(\Delta V\) , for two points located at distances \(r_B=2\text{cm}\) and \(r_A=1\text{cm}\) , we can determine the charge density on the wire:
\[\begin{aligned} \Delta V &=V(r_B)-V(r_A)=-100\text{V}\\[4pt] \Delta V &=\frac{\lambda}{2\pi\epsilon_0}\ln\left(\frac{r_A}{r_B}\right)\\[4pt] \therefore \lambda &= \frac{2\pi\epsilon_0\Delta V}{\ln\left(\frac{r_A}{r_B}\right)}=\frac{2\pi(8.85\times 10^{-12}\text{C}^2\cdot \text{N}^{-1}\cdot \text{m}^{-2})(-100\text{V})}{\ln\left(\frac{1}{2}\right)}=8.02\times 10^{-9}\text{C/m}\end{aligned}\]
where, again, one needs to be very careful with the signs! Note that it also makes sense that the potential difference, \(\Delta V =V(r_B)-V(r_A)\) , is negative, since \(r_A\) is closer to the positively charged wire. A positive charge at rest would move away from the positively charged wire, from \(r_A\) to \(r_B\) , from high potential to low potential.
Discussion
In this example, we showed how to determine the electric potential near an infinitely long charged wire by using the electric field that we determined from Gauss’ Law. By knowing the potential difference between two points near the wire, we were then able to infer the charge density on the wire.


2.2: When There is No Unique Solution
Given \(n\) equations and \(n\) unknowns, one usually expects a unique solution. But two other possibilities exist: there could be no solution, or an infinite number of solutions. We will illustrate what happens during Gaussian elimination in these two cases. Consider
\[\begin{aligned}-3x_1+2x+2-x_3&=-1, \\ 6x_1-6x_2+7x_3&=-7, \\ 3x_1-4x_2+6x_3&=b.\end{aligned} \nonumber \]
Note that the first two equations are the same as in (2.1.1) , but the left-hand-side of the third equation has been replaced by the sum of the left-hand-sides of the first two equations, and the right-hand-side has been replaced by the parameter \(b\). If \(b = −8\), then the third equation is just the sum of the first two equations and adds no new information to the system. In this case, the equations should admit an infinite number of solutions. However, if \(b\neq −8\), then the third equation is inconsistent with the first two equations and there should be no solution.
We solve by Gaussian elimination to see how it plays out. Writing the augmented matrix and doing row elimination, we have
\[\left(\begin{array}{rrrr}-3&2&-1&-1\\6&-6&7&-7\\3&-4&6&b\end{array}\right)\to\left(\begin{array}{rrrc}-3&2&-1&-1\\0&-2&5&-9\\0&-2&5&b-1\end{array}\right)\to\left(\begin{array}{rrrc}-3&2&-1&-1 \\ 0&-2&5&-9\\0&0&0&b+8\end{array}\right).\nonumber \]
Evidently, Gaussian elimination has reduced the last row of the matrix \(\text{A}\) to zeros, and the last equation becomes
\[0=b+8.\nonumber \]
If \(b\neq −8\), there will be no solution, and if \(b = −8\), the under-determined systems of equations becomes
\[\begin{aligned}-3x_1+2x_2-x_3&=-1 \\ -2x_2+5x_3&=-9.\end{aligned} \nonumber \]
The unknowns \(x_1\) and \(x_2\) can be solved in terms of \(x_3\) as
\[x_1=\frac{10}{3}+\frac{4}{3}x_3,\quad x_2=\frac{9}{2}+\frac{5}{2}x_3,\nonumber \]
indicating an infinite family of solutions dependent on the free choice of \(x_3\).
To be clear, for a linear system represented by \(\text{Ax} = \text{b}\), if there is a unique solution then \(\text{A}\) is invertible and the solution is given formally by
\[\text{x}=\text{A}^{-1}\text{b}.\nonumber \]
If there is not a unique solution, then \(\text{A}\) is not invertible. We then say that the matrix \(\text{A}\) is singular. Whether or not an \(n\)-by-\(n\) matrix \(\text{A}\) is singular can be determined by row reduction on \(\text{A}\). After row reduction, if the last row of \(\text{A}\) is all zeros, then \(\text{A}\) is a singular matrix; if not, then \(\text{A}\) is an invertible matrix. We have already shown in the two-by-two case, that \(\text{A}\) is invertible if and only if \(\det\text{ A}\neq 0\), and we will later show that this is also true for \(n\)-by-\(n\) matrices.


A drug may be defined as any substance other than food that, when taken into the body, affects the structure and/or functioning of the body. Defined this way, many common substances contain drugs or are drugs: coffee, No-Doz, and other products to keep us alert; aspirin, acetaminophen, ibuprofen, and other pain relievers; Tums, Rolaids, and other products that reduce heartburn; Metamucil and other products that reduce constipation; Robitussin, Sudafed, and other cold medicines; and so forth. If you have ever used one of these products, you are technically a drug user, however silly that might sound.
Many prescription drugs also certainly exist: Prozac and other antidepressants; Valium and other tranquilizers; Lipitor and other cholesterol drugs; Yasmin, Yaz and other birth control pills; Viagra and other products that relieve erectile dysfunction; and so forth. Sales of these prescription drugs amount to tens of billions of dollars annually.
The following substances are also drugs: alcohol, ecstasy, cocaine, heroin, marijuana, LSD, methamphetamine, PCP, and tobacco. Much has been written about these drugs, and we will discuss them further later in this section. But note that two of these drugs, alcohol and tobacco, are legal after a certain age, while the remaining drugs are illegal.
One of the problems in deciding how to think about and deal with drugs is that this distinction between legal drugs and illegal drugs has no logical basis. It makes sense to assume that the illegal drugs should be the ones that are the most dangerous and cause the most physical and social harm, but that is not true. Rather, alcohol and tobacco cause the most harm even though they are legal. As Kleiman et al. (2011, p. xviii) note about alcohol, “When we read that one in twelve adults suffers from a substance abuse disorder or that 8 million children are living with an addicted parent, it is important to remember that alcohol abuse drives those numbers to a much greater extent than does dependence on illegal drugs.” Tobacco kills about 435,000 Americans annually by causing premature death, and alcohol kills about 85,000 annually through its effects on the liver and other body organs (Mokdad, Marks, Stroup, & Gerberding, 2004).
Putting these numbers together, some 520,000 Americans die annually from alcohol and tobacco use. Meanwhile, the physiological effects of all illegal drugs combined kill an estimated 17,000 Americans annually (Mokdad et al., 2004), a number that is only just above the number of annual deaths (16,500) from nonsteroidal inflammatory drugs (NSAIDs) such as aspirin and ibuprofen (Frech & Go, 2009). Figure 7.1 “Annual Deaths from Legal and Illegal Drugs” depicts the huge difference between deaths from alcohol and tobacco as legal drugs and from illegal drugs.
Figure 7.1
Annual Deaths from Legal and Illegal Drugs
Source: Mokdad, A. H., Marks, J. S., Stroup, D. F., & Gerberding, J. L. (2004). Actual causes of death in the United States, 2000.
Journal of the American Medical Association, 291
(10), 1238–1245.
We return to the issue of the relative harm of legal and illegal drugs toward the end of the chapter when we discuss drug policy. In the meantime, keep in mind two related facts: (1) all drugs can be dangerous, and (2) some drugs are much more dangerous than others.  Two cups of coffee a day are fine, but drinking many cups a day can cause anxiety, insomnia, and headaches. One drink of alcohol is safe to take, but several drinks in a short time amount to binge drinking, and long-term use of alcohol can kill someone. One snort of cocaine is usually safe, but even one snort can result in a sudden fatal heart attack, and long-term use often has serious health consequences.
Types of Drugs
Drugs are commonly classified into certain categories according to their physiological effects. All drugs may make us feel good, but they do so in different ways. Because some drugs are much more potent than other drugs, there is much variation within each category. Partly because many drugs have multiple effects, many different classifications of drugs exist. A common classification includes the following categories: depressants, hallucinogens, marijuana, narcotics, and stimulants.
Depressants
Depressants
slow down the activity of the central nervous system. Depending on the specific drug, they help induce drowsiness and relaxation, and they can reduce anxiety and pain. Several types of depressants exist.
Analgesics
reduce pain and include over-the-counter products such as aspirin, acetaminophen (the major ingredient in Tylenol), and ibuprofen (the major ingredient in Advil and Motrin), and many prescription medicines that contain acetaminophen.
Sedatives
help people relax and include alcohol, barbiturates, and sleep medicines such as Sominex and Tylenol PM (both over-the-counter) and Ambien and Valium (both prescription). Large doses of depressants may lead to physical dependence and sometimes death.
Hallucinogens
Hallucinogens
are mind-altering drugs that cause delusions or hallucinations. Their ranks include ecstasy, LSD, mescaline, and PCP. Many people who use a hallucinogen report that the mind-altering effects of the drug provide them a truly wonderful experience, but many also find the effects to be troubling at best and horrible and terrifying at worst. Long-term effects include hallucinations that occur without any drug use preceding them.
Marijuana
Marijuana is by far the most popular illegal drug in the United States.
© Thinkstock
Because marijuana’s effects do not fit neatly into any other category of drug, marijuana (along with its close cousin, hashish) is often considered to be its own category. As we will see later, it is by far the most popular illegal drug in the United States. Its effects include distortion of time and space, euphoria, hunger, increased sensory perception, and relaxation.
Narcotics
Narcotics
are sometimes classified under depressants because they slow down the central nervous system, but they are often still considered as their own category. They are highly effective at relieving pain and are a common substance in prescription medicines for severe pain. By definition, all narcotics are derived from opium, either in its natural form or in a synthesized form. Examples of narcotics include codeine, heroin, methadone, and morphine. In addition to relieving pain, narcotics may induce drowsiness, euphoria, and relaxation. Although narcotics do not damage bodily organs, they are very physically addictive, and high doses can be fatal.
Stimulants
Stimulants
have the opposite effect of depressants by speeding up the central nervous system. They increase alertness and energy and can produce euphoria or anxiety. Some are legal and some are illegal, and many very different drugs are all considered stimulants: caffeine, cocaine, methamphetamine and other amphetamines, nicotine (tobacco), and Ritalin. Stimulants can be very physically addictive, and nicotine is thought to be more addictive than heroin. While caffeine is very safe as long as someone does not have too many cups of coffee daily, many other stimulants may have dangerous short-term or long-term side effects on the cardiovascular system.
Not all drugs can be discussed in one chapter. In choosing which drugs to discuss in a book on social problems, it makes sense to discuss the drugs that probably concern Americans the most. We thus focus in the remainder of this section mostly on alcohol, tobacco, marijuana, cocaine, and heroin.
Legal Drugs
As noted earlier, alcohol and tobacco (nicotine) are two legal drugs that are very common and that together kill hundreds of thousands of Americans annually. According to national survey evidence collected by the Substance Abuse and Mental Health Services Administration (SAMHSA) of the federal government, most people 12 and older (as well as many younger than 18) have tried alcohol, and over half the public drinks currently (defined as having had at least one drink in the past month). While many people have tried tobacco, only slightly more than one-fourth of the public uses it currently (at least once during the past month). Table 7.1 summarizes the prevalence of alcohol and nicotine use. Translating some of these percentages into actual numbers, almost 70 million Americans are current tobacco users (mostly by smoking cigarettes), and 131 million are current alcohol users.
Table 7.1 Prevalence of Alcohol and Tobacco Use, Ages 12 and Older, 2010*
|
|
Lifetime
|
Past year
|
Past month
|
|
Alcohol
|
82.5
|
66.4
|
51.8
|
|
Tobacco
|
68.7
|
32.8
|
27.4
|
|
* Percentage using in designated time period
|
Source: Substance Abuse and Mental Health Services Administration. (2011).
Results from the 2010 national survey on drug use and health: Summary of national findings
. Rockville, MD: Author.
With this backdrop, we now discuss these two legal but very harmful drugs in greater detail.
Alcohol
Moderate alcohol use (more than one drink per day for an adult female and two drinks per day for an adult male) is relatively safe for most people and may even have health benefits (Harvard School of Public Health, 2012).Harvard School of Public Health. (2012). Alcohol: Balancing risks and benefits. Retrieved March 30, 2012, from
http://www.hsph.harvard.edu/nutritionsource/what-should-you-eat/alcohol-full-story/index.html
. The problem is that many people drink much more than moderately. As the Harvard School of Public Health (2012)Harvard School of Public Health. (2012). Alcohol: Balancing risks and benefits. Retrieved March 30, 2012, from
http://www.hsph.harvard.edu/nutritionsource/what-should-you-eat/alcohol-full-story/index.html
. explains, “If all drinkers limited themselves to a single drink a day, we probably wouldn’t need as many cardiologists, liver specialists, mental health professionals, and substance abuse counselors. But not everyone who likes to drink alcohol stops at just one. While most people drink in moderation, some don’t.”
SAMHSA survey data show the extent of such problem drinking, as its survey measures both
binge drinking
(five or more drinks on the same occasion—within two hours of each other—on at least one day in the past month) and
heavy drinking
(binge drinking on at least five days in the past month). Table 7.2 presents the relevant data for people 12 and older and also for those aged 18–20, the customary age for people in their first two years of college.
Table 7.2 Prevalence of Binge and Heavy Alcohol Use, 2010*
|
|
Ages 12 and older
|
Ages 18–20
|
|
Binge use
|
23.1
|
33.3
|
|
Heavy use
|
6.7
|
11.3
|
|
* Percentage engaging in alcohol use
|
Source: Substance Abuse and Mental Health Services Administration. (2011).
Results from the 2010 national survey on drug use and health: Summary of national findings
. Rockville, MD: Author.
As Table 7.2 indicates, almost one-fourth of all people 12 and older and one-third of those aged 18–20 engage in binge drinking, while almost 7 percent and about 11 percent, respectively, engage in heavy drinking. The figures for those 12 and older translate to almost 59 million binge drinkers and 17 million heavy drinkers. These numbers show that tens of millions of people abuse alcohol annually and underscore the problem of dealing with problem drinking.
The amount of alcohol consumed annually by occasional, moderate, and heavy drinkers is staggering. The relevant data appear in Table 7.3. Americans drink 7.6 billion gallons of alcohol annually, equivalent to 126 billion standard drinks. This number of drinks works out to 496 drinks per person annually for the 12 and older population and 748 drinks per person for the 12 and older population that drinks at all. Keep in mind that this is just an average. The heavy drinkers identified in Table 7.2 have many more than 748 drinks every year, while light drinkers have only a relative handful of drinks.
Table 7.3 Alcohol Consumption in the United States, 2010
|
|
Number of gallons
|
Equivalent number of standard drinks*
|
|
Beer
|
6.4 billion
|
68.2 billion
|
|
Wine
|
713.2 million
|
18.3 billion
|
|
Spirits
|
463.1 million
|
39.5 billion
|
|
Total
|
7.6 billion
|
126.0 billion
|
|
* one drink = 12 ounces of beer, 5 ounces of wine, or 1.5 ounces of spirits
|
Source: Beer Institute. (2011).
Brewers almanac, 2011
. Washington, DC: Author.
The Drinking Culture and the Alcohol Industry
As noted earlier, alcohol has a long history in the United States and an even longer history in much of the rest of the world. When we think about the tens of millions of Americans who drink at least occasionally, the ads for beer and wine and hard liquor that appear regularly in the popular media, and the thousands of bars and related venues across the country, it is certainly no exaggeration to say that we have a drinking culture.
Once upon a time, the federal and state governments tried to eliminate this culture. We are speaking, of course, about Prohibition. The passage of the Eighteenth Amendment to the US Constitution in January 1919 banned the manufacture, sale, and transportation of alcohol; the ban took effect a year later. For reasons we will discuss later, the ban was eventually deemed a failure, and the passage of the Twenty-First Amendment in 1933 repealed the Eighteenth Amendment. The manufacture, sale, and transportation of alcohol became legal once again.
Alcohol manufacturing and sales are a major industry worldwide today. Several alcohol companies rank among the largest corporations in the world as well as in the United States (Jernigan, 2009).Jernigan, D. H. (2009). The global alcohol industry: An overview [Supplmental material].
Addiction, 104
, 6–12. US alcohol sales amount to about $160 billion annually, and they rose by 20 percent in the 2010–2011 period during the faltering economy (Smith, 2011).Smith, A. (2011, June 9). Alcohol Sales Thrive in Hard Times.
CNN
. Retrieved from
http://money.cnn.com
. The amount of money the public spends on alcohol equals 12.5 percent of what it spends on food (US Department of Agriculture, 2011).US Department of Agriculture. (2011). Food CPI and expenditures: Table 1. Retrieved September 19, 2011, from
http://www.ers.usda.gov/Briefing/CPIFoodAndExpenditures/Data/Expenditures_tables/table1.htm
. The alcohol industry provides about 2 million jobs annually, more than $40 billion in wages, and more than $50 billion in taxes, and it contributes more than $160 billion to the annual national economy (Distilled Spirits Council of the United States, 2011).Distilled Spirits Council of the United States. (2011). Economic contribution of alcohol beverage industry. Retrieved September 19, 2011, from
http://www.discus.org/pdf/ATT2_Economic_Contribution.pdf
. All these figures show that the alcohol industry plays a significant role in the US economy.
Despite this role, if the United States does indeed have a drinking culture, the alcohol industry bears a major share of the responsibility. As the American Medical Association (2004)American Medical Association. (2004).
Alcohol industry 101: Its structure & organization
. Chicago, IL: Author. has stated,
Like the tobacco industry, the alcohol industry produces a legal, widely consumed drug; is dominated by relatively few producers; and utilizes a powerful combination of advertising dollars, savvy marketing, political campaign contributions, and sophisticated lobbying tactics to create and maintain an environment favorable to its economic and political interests. It requires the recruitment of new, youthful drinkers to maintain and build its customer base…As a chemical that affects our bodies, alcohol is a powerful drug resulting in more premature deaths and illnesses than all illicit drugs combined. Yet the industry has shaped public opinion and forced government to treat it not as a drug but as a cultural artifact, a valued legal commodity, almost a food, even a necessity of life.
As just one example of how the alcohol industry promotes its “powerful drug,” the headline of a recent news article declared that the “alcohol companies go online to lure young drinkers” (Gardner, 2010).Gardner, A. (2010, May 3). Report: Alcohol Companies go online to lure young drinkers.
USA Today
. Retrieved from
http://www.usatoday.com/news/health/index
. According to the report, alcohol companies are increasingly using Facebook and other social media to persuade young people to buy and drink their products. Not surprisingly, many of these young targets turn out to be under the legal drinking age of 21 because they are easily able to gain access to alcohol sites. This problem led a public health professor to observe, “Close to 5,000 people under the age of 21 die of alcohol overuse each year. Virtual worlds show all of the appeal and none of the consequences of alcohol use and undercut efforts to reduce the incidence of underage drinking. At this point, alcohol companies appear limited only by their imaginations and pocketbooks” (Gardner, 2010).Gardner, A. (2010, May 3). Report: Alcohol companies go online to lure young drinkers.
USA Today
. Retrieved from
http://www.usatoday.com/news/health/2010-05-23-alcohol-teens_N.htm
.
The alcohol industry is a major part of the US and worldwide economies and provides about 2 million jobs annually in the United States.
© Thinkstock
Consequences of Alcohol Abuse
Despite alcohol’s immense popularity, the fact remains that more than 18 million Americans abuse it (Harvard School of Public Health, 2012).Harvard School of Public Health. (2012). Alcohol: Balancing risks and benefits. Retrieved March 31, 2012, from
http://www.hsph.harvard.edu/nutritionsource/what-should-you-eat/alcohol-full-story/index.html
. This heavy rate of abuse means that alcohol has serious personal and social consequences. One set of consequences involves personal health. We noted earlier that alcohol abuse is responsible for about 85,000 deaths annually through the physiological damage it does.  It can lead to neurological problems and also raises the risk of incurring several kinds of cancer. Binge drinking can cause serious immediate health problems because it may lead to someone overdosing on alcohol. About 800,000 adults are hospitalized every year for alcohol overdoses, and tens of thousands more are hospitalized because they have consumed alcohol along with prescription narcotic pain medications, a combination that can be deadly (National Institutes of Health, 2011).National Institutes of Health. (2011). NIH study finds hospitalizations increase for alcohol and drug overdoses. Retrieved September 21, 2011, from
http://www.nih.gov/news/health/sep2011/niaaa-20.htm
.
In addition to these health problems, alcohol use is responsible for more than 16,000 traffic fatalities annually, and it plays an important role in violent crime (Felson, Teasdale, & Burchfield, 2008).Felson, R. B., Teasdale, B., & Burchfield, K. B. (2008). The influence of being under the influence.
Journal of Research in Crime & Delinquency, 45
(2), 119–141. As almost anyone with an alcoholic family member can attest, alcohol abuse can also cause many problems for families, including domestic violence and divorce and the stress that results from having to deal with someone’s alcoholism on a daily basis. (The
Note 7.13 "Children and Our Future"
box discusses the impact of parental alcoholism on children.) Alcohol abuse costs the United States more than $185 billion each year in medical expenses, lost earnings because of alcohol-related illness or premature death, lost earnings by victims of violent crime, and alcohol-caused traffic accidents (Harvard School of Public Health, 2012).Harvard School of Public Health. (2012). Alcohol: Balancing risks and benefits. Retrieved March 31, 2012, from
http://www.hsph.harvard.edu/nutritionsource/what-should-you-eat/alcohol-full-story/index.html
.
Children and Our Future
Children of Alcoholics
As with so many social problems, one of the saddest consequences of alcohol abuse involves children. About one-fifth of children have lived with an alcoholic parent or other adult. Whether because alcoholism is partly inherited or because children tend to use their parents as role models, children of alcoholics are four times more likely than children of nonalcoholics to become alcoholics themselves by the time they reach adulthood.
Because living with an alcoholic parent is often both chaotic and unpredictable, it is no surprise that children of alcoholics often experience a great deal of stress and other difficulties that may also account for their greater tendency to become alcoholics. Compared to other children, they are more likely to be neglected and/or abused by their parents, and they are also more likely to miss school, have lower grades, and engage in disruptive behavior. In addition, they are at great risk for eating disorders and substance abuse other than alcohol abuse. The stress they experience can also harm their neurological development and immune system and put them at greater risk for different kinds of illness and disease. Children of alcoholics are also at greater risk for several kinds of psychological and emotional problems. These include (1)
guilt
, because they may blame themselves for their parent’s drinking; (2)
anxiety
, because they worry about their parent’s health and may see their parents arguing and fighting; (3)
embarrassment
that leads them not to invite friends over to visit nor to ask another adult for help; (4)
lack of trust
in other people, because they have learned not to trust their alcoholic parent; and (5)
anger
,
confusion
, and
depression
.
One special problem that children of alcoholics face is that they are “forced into adulthood.” They often find themselves having to care for younger siblings and even for their alcoholic parent. By taking on such a heavy responsibility, they in effect become adults at too tender an age. This responsibility weighs on them and helps account for the psychological and emotional difficulties they often experience.
Mental health professionals strongly advise that children of alcoholics receive counseling and other kinds of support to help them deal with their family experiences. Group support programs for teenaged children may be very helpful. Perhaps the best known such program is Alateen, which also services teenagers who want help dealing with an alcoholic friend. Teenagers at Alateen meetings share their experiences, learn how to deal with the special difficulties that stem from having a relative or friend with an alcohol problem, and provide emotional support for each other. One important message they learn from Alateen is that they are in no way responsible for the alcoholism of their parent, other relative, or friend.
Alateen has helped many young people, as this testimonial from “Lizzy” attests: “Alateen has helped me a lot over the years…From the day I went to my first meeting, the door to my happiness was flung open. With the help of the Alateen Group Sponsors and my fellow teens, my life has become what I always wanted it to be. My goal for success in the program was fulfilled. I have been given a second chance at life and I have Alateen to thank for that.”
Young children and teenagers are resilient, but children of alcoholics have to be especially resilient. Programs like Alateen help give them a second chance.
Sources:
Alateen, 2011; American Academy of Child and Adolescent Psychiatry, 2006; James, 2008Alateen. (2011). Am I a peacemaker or a creator of chaos.
Alateen Talk
. Retrieved from http[0]://www.al-anon.org/alateen-talk; American Academy of Child and Adolescent Psychiatry. (2006). Children of alcoholics. Retrieved October 4, 2011, from
http://www.aacap.org/galleries/FactsForFamilies/17_children_of_alchoholics.pdf
; James, S. D. (2008, September 10). Children of alcoholics forced into adulthood.
abcnews.com
. Retrieved from
http://abcnews.go.com/Health/story?id=5770753&page=5770751
.
College Students
Alcohol abuse is also a problem on college and university campuses across the United States. Based on the SAMHSA survey evidence discussed earlier, full-time college students ages 18–22 drink more often and more heavily than their peers who are not in college (Substance Abuse and Mental Health Services Administration, 2008).Substance Abuse and Mental Health Services Administration. (2008). Underage alcohol use among full-time college students. Retrieved September 20, 2011, from
http://oas.samhsa.gov/2k6/college/collegeUnderage.htm
. Among full-time college students ages 18–20, who are all too young to drink legally, about 40 percent have engaged in binge drinking in the past month, and 17 percent have engaged in heavy drinking as defined earlier. Binge drinking on and off campus is so common that binge drinkers consume 91 percent of all the alcohol that college students drink.
Binge drinking by college students has many serious consequences (Center for Science in the Public Interest, 2008; National Center on Addiction and Substance Abuse, 2007).Center for Science in the Public Interest. (2008). Binge drinking on college campuses. Retrieved September 20, 2011, from
http://www.cspinet.org/booze/collfact1.htm
; National Center on Addiction and Substance Abuse. (2007).
Wasting the best and the brightest: Substance abuse at America’s colleges and universities
. New York, NY: Author. The following are consequences with approximate figures:
-
Binge drinkers are much more likely than other students to miss class, get poor grades, be injured, have unprotected sex, and to drive after drinking.
-
Six hundred thousand college students suffer alcohol-related injuries (from motor vehicle crashes and other accidents) each year, and 1,700 die from these injuries.
-
Thirty thousand college students need medical attention annually to treat alcohol overdosing.
-
Seven hundred thousand students are assaulted annually by a student who has been drinking, and three hundred students die from these assaults.
-
Students who attend colleges with high rates of binge drinking are more likely to experience sleep disruption, property damage, and physical and sexual assaults than those who attend colleges with low rates of binge drinking.
Tobacco and Nicotine
Nicotine, the major drug in tobacco, is another legal but very dangerous drug. As we saw earlier, its use kills four times as many people every year as those killed by alcohol use. Tobacco is a slow poison. If it were not already a legal drug used by millions, and a company had just manufactured cigarettes for the first time, the Food and Drug Administration would never approve this product. Fortunately for tobacco companies, nicotine does not distort perception the way that alcohol and many other psychoactive drugs do. Someone smoking or otherwise using tobacco can safely drive a car, operate machinery, and so forth, and someone “under the influence” of tobacco does not become violent.
Tobacco is a slow poison. If it were a new drug, it would not be approved for public consumption.
© Thinkstock
If you have ever watched any number of pre-1970s movies or television shows like “Mad Men” that portray life back then, you know that the United States used to have a tobacco culture the way it now has an alcohol culture. Many, many people smoked cigarettes, and a large number smoked cigars or pipes. This particular drug culture began to abate in the 1970s after much evidence mounted about the deaths and other serious health effects of tobacco use and especially about the dangers of second-hand smoke. Whereas college students a generation ago often sat in smoke-filled classrooms and Americans generally sat in smoke-filled restaurants and other venues, today most Americans can count on being in enclosed public spaces in which smoking is banned.
Even so, we have already seen that more than one-fourth of Americans 12 and older, or some 70 million people, are still current users (past month) of tobacco. Almost one-fifth of American adults (18 and older), or 45.3 million adults, smoke cigarettes daily or occasionally (King, Dube, Kaufmann, Shaw, & Pechacek, 2011).King, B., Dube, S., Kaufmann, R., Shaw, L., & Pechacek, T. (2011). Vital signs: Current cigarette smoking among adults aged ≥18 years—United States, 2005–2010.
Morbidity and Mortality Weekly Report, 60
(35), 1207–1212. Thanks to the greater knowledge about tobacco’s health effects, public education campaigns about these effects, heavy taxes on cigarettes, and changing attitudes about tobacco, these numbers represent a significant decline from a generation ago.
Tobacco use causes more preventable death and illness in the United States than any other cause of death; if no one used tobacco, the more than 400,000 tobacco-related deaths each year would not occur. As we think about tobacco, this startling statistic needs to be kept in mind:
About half of all cigarette smokers will one day die from a premature death caused by a smoking-related illness
(King et al., 2011).King, B., Dube, S., Kaufmann, R., Shaw, L., & Pechacek, T. (2011). Vital signs: Current cigarette smoking among adults aged ≥18 years—United States, 2005–2010.
Morbidity and Mortality Weekly Report, 60
(35), 1207–1212. To repeat what was said just earlier, nicotine is a slow poison.
Tobacco kills in several ways. Smoking causes 80–90 percent of all lung cancers, and it greatly increases the risk of emphysema and other lung disease, coronary heart disease, and stroke.  Women who smoke are at greater risk for lower bone density and hip fracture when they get older.
The economics of tobacco use are also worth knowing. Americans spend about $90 billion annually on tobacco products, with most of this amount spent on cigarettes (Centers for Disease Control and Prevention, 2011).Centers for Disease Control and Prevention. (2011). Economic facts about US tobacco production and use. Retrieved September 20, 2011, from
http://www.cdc.gov/tobacco/data_statistics/fact_sheets/economics/econ_facts/
. They purchase more than 300 billion cigarettes annually, with most of the cigarettes sold by three companies. Cigarette smoking is estimated to cost almost $200 billion annually in medical expenses and lost economic productivity. This works out to a national economic loss of about $10.50 for every pack of cigarettes that is sold.
One interesting and very important fact about the economics of cigarette smoking is what happens when the cost of cigarettes is increased. Most smokers begin their deadly habit during adolescence or young adulthood. Because this is a period of their lives when they do not have much money, increases in the cost of cigarettes are particularly useful in persuading some of these young people not to buy cigarettes. Government data indicate that every 10 percent increase in the price of cigarettes reduces cigarette consumption among young people by 4 percent (Centers for Disease Control and Prevention, 2011).Centers for Disease Control and Prevention. (2011). Economic facts about US tobacco production and use. Retrieved September 20, 2011, from
http://www.cdc.gov/tobacco/data_statistics/fact_sheets/economics/econ_facts/
. A similar but smaller effect occurs among older smokers.
Earlier we said that the alcohol industry plays a major role in the amount of drinking that occurs in the United States. The same is true of the tobacco industry and smoking. This industry spends about $15 billion annually—or an average of $41 million daily—in advertising, sponsorship of public events, and other activities to promote its deadly product, and for many years hid or distorted data about the deadly effects of cigarette smoking (Brandt, 2009).Brandt, A. (2009).
The cigarette century: The rise, fall, and deadly persistence of the product that defined America
. New York, NY: Basic Books. Because of funding cutbacks during the recent faltering economy, the states have reduced their media campaigns and other efforts aimed at reducing smoking. This reduction, combined with the tobacco industry’s huge promotional spending, leads one public health professor to lament, “The tobacco companies are winning the battle” (Martin, 2011).Martin, T. W. (2011, September 6). Fewer Americans are smoking, and those who do puff less.
The Wall Street Journal
. Retrieved from
http://blogs.wsj.com/health/2011/2009/2006/fewer-americans-are-smoking-and-those-who-do-puff-less/
.
Illegal Drugs
The SAMHSA survey also gathers data from its thousands of respondents about illegal drug use. Table 7.4 presents these data for several illegal drugs and shows that use of these drugs is far from rare.
Table 7.4 Prevalence of Illegal Drug Use, Ages 12 and Older, 2010*
|
|
Lifetime
|
Past year
|
Past month
|
|
Any illegal drug
|
47.1
|
15.3
|
8.9
|
|
Illegal drug other than marijuana
|
30.0
|
8.1
|
3.6
|
|
Marijuana/hashish
|
41.9
|
11.5
|
6.9
|
|
Cocaine/crack
|
14.7
|
1.8
|
0.6
|
|
Hallucinogens
|
14.8
|
1.8
|
0.5
|
|
Heroin
|
1.6
|
0.2
|
0.1
|
|
Stimulants
|
8.5
|
1.1
|
0.4
|
|
Nonmedical use of prescription-type drugs†
|
20.4
|
6.3
|
2.7
|
|
* Percentage using in designated time period
|
|
† Includes stimulants
|
Source: Substance Abuse and Mental Health Services Administration. (2011).
Results from the 2010 national survey on drug use and health: Summary of national findings
. Rockville, MD: Author.
The following figure from Table 7.5 is striking: 47.1 percent of all Americans ages 12 and older have used an illegal drug at least once in their lifetimes. This percentage translates to almost 120 million people. In terms of lifetime use, the single most popular illegal drug is easily marijuana, but 30 percent of Americans, or 76 million people, have used an illegal drug other than marijuana. Almost 15 percent, or more than 37 million people, have used cocaine/crack or hallucinogens, and more than 20 percent, or almost 52 million people, have used prescription drugs illegally. These percentages and the numbers of people associated with them all indicate that lifetime illegal drug use in the United States is widespread.
Despite this fact, most public health experts are primarily concerned with current (past month) illegal drug use. The percentages for past-month (and also past-year) use in Table 7.5 are noticeably smaller than those for lifetime use. They indicate that most people who have used illegal drugs in their lifetimes are no longer using them, or at least have not used them in the past year or past month. Most of these lifetime users tried their illegal drug once, twice, or a few times and then stopped using it, and some may have used it more often but then stopped. In any event, it is the current, past-month users who raise the most concern for our society in general and for the public health and legal communities and other sectors of our society that deal with illegal drug use and its effects.
In looking at current illegal drug use, we see that 8.9 percent of the public falls into this category. This percentage translates to almost 23 million Americans, no small number by any means. Their favorite illegal drug is marijuana (and hashish), but 3.6 percent, or 9 million people, have used an illegal drug other than marijuana in the past month. These users favor prescription drugs used for nonmedical reasons. Despite the publicity that cocaine/crack still receives, less than 1 percent of the public has used it in the past month, and less than 2 percent has used it in the past year. These small percentages, though, still translate to 1.5 million people and 5.5 million people, respectively.
The percentages in Table 7.4 underestimate the problem of illegal drug use in at least two respects. First, the SAMHSA survey does not include people whose illegal drug use is especially high: the homeless, runaway teenagers, jail and prison inmates, and youths in detention centers. Second, and conversely, the SAMHSA survey includes people whose illegal drug use is relatively low—namely, young adolescents and people in their middle age and older years. For this reason, it is instructive to examine the prevalence of illegal drug use among the people who are in their “prime” ages for it: those who are 18–20 years old. Accordingly, Table 7.5 presents the appropriate figures for Americans in this age group.
Table 7.5 Prevalence of Illegal Drug Use, Ages 18–20, 2010*
|
|
Lifetime
|
Past year
|
Past month
|
|
Any illegal drug
|
52.8
|
37.7
|
23.1
|
|
Illegal drug other than marijuana
|
31.2
|
19.1
|
8.0
|
|
Marijuana/hashish
|
46.4
|
32.7
|
20.3
|
|
Cocaine/crack
|
8.5
|
4.1
|
1.2
|
|
Hallucinogens
|
14.1
|
7.9
|
2.3
|
|
Heroin
|
1.6
|
0.5
|
0.2
|
|
Stimulants
|
7.8
|
3.9
|
1.3
|
|
Nonmedical use of prescription-type drugs†
|
24.5
|
14.5
|
5.9
|
|
* Percentage using in designated time period
|
|
† Includes stimulants
|
Source: Substance Abuse and Mental Health Services Administration. (2011).
Results from the 2010 national survey on drug use and health: Summary of national findings
. Rockville, MD: Author.
Take a moment to compare the percentages in Table 7.5 for ages 18–20 to the percentages in Table 7.4 for ages 12 and older. When you do this, you will see that past-year and past-month illegal drug use is generally much higher for people ages 18–20 than for everyone 12 and older. More than one-third of the 18–20 age group have used an illegal drug in the past year, and almost one-fourth are current users, having used an illegal drug in the past month. As with the 12 and older population, their drug of choice is clearly marijuana, with nonmedical use of prescription-type drugs a distant second.
This last statement is important to keep in mind. In terms of percentages, the major illegal drug is marijuana. Very low percentages of Americans use other illegal drugs when we consider current use and past-year use, although a greater number have experimented with other illegal drugs in their lifetimes. As we have seen, however, the low percentages for the other illegal drugs still translate into millions of Americans who are current users of illegal drugs other than marijuana. It is also true that drugs like heroin and cocaine/crack are used more heavily in large cities than in smaller cities and towns and rural areas. Although these drugs are only rarely used nationwide, they are a particular problem in large urban areas.
With this backdrop in mind, we now discuss a few illegal drugs in further detail.
Marijuana
As we have seen, marijuana is easily the most widely used illegal drug in the United States. The percentages for marijuana use in Table 7.4 translate to 106 million people who have ever used marijuana, 29 million people who used it in the past year, and 17 million people who used it in the past month (current users). As Table 7.5 showed, marijuana use is especially high among young people: One-third of people ages 18–20 have used marijuana in the past year, and one-fifth are current users.
Marijuana use can cause several problems (National Institute on Drug Abuse, 2010).National Institute on Drug Abuse. (2010). InfoFacts: Marijuana. Retrieved September 22, 2011, from
http://www.nida.nih.gov/infofacts/marijuana.html
. Marijuana distorts perception, impairs coordination, and can cause short-term memory loss, and people who are high from marijuana may be unable to safely drive a motor vehicle or operate machinery. In addition, regular pot smokers are at risk for respiratory problems, though not lung cancer. Chronic marijuana use is also associated with absence from school and the workplace and with social relationship problems, although it is difficult to determine whether marijuana is causing these effects or whether the association exists because someone with personal problems begins using marijuana regularly.
Despite these problems, marijuana is almost certainly the most benign illegal drug in terms of health and social consequences, and it is also much more benign than either alcohol or tobacco (Drug Policy Alliance, 2011; Faupel et al., 2010).Drug Policy Alliance. (2011). Marijuana facts. Retrieved September 22, 2011, from
http://www.drugpolicy.org/facts/drug-facts/marijuana-facts
; Faupel, C. E., Horowitz, A. M., & Weaver., G. S. (2010).
The sociology of American drug use
. New York, NY: Oxford University Press. As noted earlier, these latter two drugs kill about 520,000 Americans annually. In contrast, marijuana has probably never killed anyone, and its use has not been associated with any cancers. Alcohol use is a risk factor for violent behavior, but marijuana use is a risk factor for mellow behavior; if everyone who now uses alcohol instead smoked marijuana, our violent crime rate would probably drop significantly! Despite some popular beliefs, marijuana is generally not physiologically addictive, it does not reduce ambition and motivation, and it does not act as a “gateway drug” that leads to the use of more dangerous drugs (Hanson, Venturelli, & Fleckenstein, 2012).Hanson, G. R., Venturelli, P. J., & Fleckenstein, A. E. (2012).
Drugs and society
(11th ed.). Burlington, MA: Jones & Bartlett. A review of the evidence on marijuana summarized research findings as follows: “Studies of long-term marijuana smokers do not produce gross or major clinical, psychiatric, psychological, or social difference between users and nonusers, or between heavier and lighter users” (Goode, 2008, p. 247).Goode, E. (2008).
Drugs in American society
(7th ed.). New York, NY: McGraw Hill.
While not entirely safe, then, marijuana is much safer, both on an individual basis and on a societal basis, than either alcohol or tobacco. Even so, it remains an illegal drug. This fact underscores our earlier observation that the legality or illegality of drugs has no logical basis. If the personal and social harm caused by a drug determined whether it is legal or not, then it would be logical for marijuana to be legal and for alcohol or tobacco to be illegal.
For better or worse, though, the millions of marijuana users have broken the law. In most states, marijuana possession is a crime punishable by a jail or prison term that depends on the amount of marijuana involved. Fourteen states (Alaska, California, Colorado, Connecticut, Maine, Massachusetts, Minnesota, Mississippi, Nebraska, Nevada, New York, North Carolina, Ohio, Oregon) have decriminalized simple possession of small amounts of marijuana: They treat possession as a minor offense similar to a traffic violation and punish it with only a small fine. Most of these states decriminalized the drug in the 1970s after a national commission with members appointed by the US Congress and by President Richard Nixon recommended taking this action. There is no evidence that marijuana use in these states increased compared to use in the states that have not decriminalized marijuana (Beckett & Herbert, 2008).Beckett, K., & Herbert, S. (2008).
The consequences and costs of marijuana prohibition
. Seattle, WA: American Civil Liberties Union of Washington State. In fact, marijuana use in the nation declined sharply in the 1980s, the first decade after decriminalization began, both in the states that decriminalized pot possession and in the states that did not decriminalize it.
Cocaine
Cocaine produces a high that is considered more pleasurable than that for any other drug. According to sociologist Erich Goode (2008, p. 288)Goode, E. (2008).
Drugs in American society
(7th ed.). New York, NY: McGraw Hill., “Cocaine’s principal effects are exhilaration, elation, and euphoria—voluptuous, joyous feelings accompanied by a sense of grandiosity.” As a stimulant, cocaine also increases energy, alertness, and a sense of self-confidence. It is not physiologically addictive, but it is considered psychologically addictive: The high it produces is so pleasurable that some users find they need to keep using it.
Cocaine is a particularly addictive drug because of the high degree of pleasurable feelings it causes.
© Thinkstock
Cocaine is made from coca plants grown in South America. It most often appears in a powdered form that is sniffed (or, to use the more common term for this method, snorted). The high it produces takes some time to occur but may last up to thirty minutes once it does arrive. A more potent form, crack cocaine (or, more commonly, crack), is made by heating a mixture of powdered cocaine, baking soda, and water. A user then heats the mixture that remains and breathes in the vapors that result. Crack produces an immediate, intense high and is a relatively inexpensive drug. These features made crack a very popular drug when it was first introduced into US cities in the 1980s (Faupel et al. 2010).Faupel, C. E., Horowitz, A. M., & Weaver., G. S. (2010).
The sociology of American drug use
. New York, NY: Oxford University Press. Street gangs fought each other to control its distribution and sale, much as organized crime gangs fought each other over alcohol distribution and sale during Prohibition.
Cocaine and crack use has declined since the 1970s and 1980s, but, as Table 7.5 showed, almost 15 percent of the public has used cocaine at least once; this number translates to some 37 million Americans. Still, past-year use is only 1.8 percent, and past-month (current) use is only 0.6 percent. Cocaine use thus must be considered rare in percentage terms. At the same time, these percentages translate to 4.5 million and 1.5 million Americans, respectively. These are not small numbers. Moreover, past-year and past-month cocaine use is higher among young people, as Table 7.5 showed. Further, crack use remains a problem in the nation’s urban areas.
In terms of health risks, cocaine is a much more dangerous drug than marijuana. As a stimulant, cocaine speeds up the central nervous system. Because it does so much more intensely than most other stimulants, its use poses special dangers for the cardiovascular system (National Institute on Drug Abuse, 2011).National Institute on Drug Abuse. (2011). Cocaine: Abuse and addiction. Retrieved September 27, 2011, from
http://www.nida.nih.gov/researchreports/cocaine/effects.html
. In particular, it can disrupt the heart’s normal rhythm and cause ventricular fibrillations, and it can speed up the heart and raise blood pressure. An overdose of cocaine can thus be deadly, and long-term use produces an increased risk of stroke, seizure, and heart disease. Because cocaine also constricts blood vessels in the brain, long-term use raises the risk of attention deficit, memory loss, and other cognitive problems. Long-term abuse has also caused panic attacks, paranoia, and even psychosis.
Heroin
Heroin is derived from opium (and more immediately from morphine, an opium derivative) and is almost certainly the most notorious opiate. It was one of the popular opiate drugs that, as discussed earlier, were used so widely during the late nineteenth century. Heroin was first marketed as a painkiller and cough suppressant by the company that makes Bayer aspirin. As the United States became more concerned about opium use, Bayer Laboratories discontinued heroin marketing in 1910, and heroin, like other opiates, was banned under the 1914 Harrison Narcotic Act.
Although Table 7.4 shows that its use is minuscule in percentage terms, these percentages translate to 600,000 people who have used heroin in the past year, and 240,000 who have used in the past month. Because these users are concentrated in the nation’s large cities, heroin, like crack, is a special problem for these areas.
Like other narcotics, heroin use produces a feeling of euphoria. After it is injected, “the user feels a flash, a rush, which has been described as an intense, voluptuous, orgasmlike sensation. Following this is the feeling of well-being, tranquility, ease, and calm, the sensation that everything in the user’s life is just fine. Tensions, worries, problems, the rough edges of life—all seem simply to melt away” (Goode, 2008, pp. 308–309).Goode, E. (2008).
Drugs in American society
(7th ed.). New York, NY: McGraw Hill.
Although heroin use is uncommon, it continues to capture the public’s concern more than perhaps any other illegal drug. As sociologist Goode (2008, pp. 307–308)Goode, E. (2008).
Drugs in American society
(7th ed.). New York, NY: McGraw Hill. has observed,
For decades, it was the most feared, the most dreaded, the “hardest” drug; heroin has virtually defined the drug problem. In spite of being somewhat overshadowed since the mid-1980s by cocaine, and specifically crack, heroin probably remains the single substance the American public is most likely to point to as an example of a dangerous drug. Until recently, disapproval of any level of heroin use was greater than for any other drug. And, until recently, heroin addicts were the most stigmatized of all drug users. Heroin is the epitome of the illicit street drug. Its association in the public mind with street crime, even today, is probably stronger than for any other drug. The stereotype of the junkie is that he or she is by nature a lowlife, an outcast, a “deviant,” a dweller in the underworld, an unsavory, untrustworthy character to be avoided at any cost.
Users typically take heroin into their body by injecting it into a vein. This mode of administration is undoubtedly a major reason for the public’s very negative image of heroin users. Indeed, the image of a heroin addict “shooting up” is one that has appeared in many movies and television shows past and present. Many heroin addicts share their needles, a practice that increases their risk of contracting HIV and hepatitis.
The public’s image and concern about heroin is partly deserved in some ways and partly undeserved in other ways. Like other opiates, heroin is extremely physiologically addictive, although not as addictive as nicotine. But also like other opiates, heroin does not damage body organs. The emaciated look we often associate with heroin users stems not from the drug itself but from the low-caliber lifestyles that heroin addicts tend to live and their decisions to spend the little money they have on heroin rather than on food and a healthier lifestyle. An overdose of heroin can certainly kill, just as overdoses of other drugs can kill. One reason heroin overdoses occur is that heroin users cannot know for sure the purity of the heroin they buy illegally and thus may inject an unsafe dose to get high.
Prescription Drug Abuse
Table 7.4 showed that about one-fifth of Americans have used prescription drugs for nonmedical purposes. This type of use is illegal. It constitutes the most widespread illegal drug use other than marijuana use and has grown in recent years, especially among adolescents. The prescription drugs that are most often abused are those containing narcotics, tranquilizers, and stimulants; two of the most common brands that are abused are OxyContin and Vicodin. Because prescription drugs are beneficial for so many people even if they are abused, our nation faces a special difficulty in dealing with the abuse of these drugs. As the head of the National Institute on Drug Abuse explains, “The challenges we face are much more complex because we need to address the needs of patients in pain, while protecting those at risk for substance use disorders” (Zuger, 2011, p. D1).Zuger, A. (2011, June 14). A general in the drug war.
New York Times
. p. D1. Thus according to a news report, “These drugs must be somehow legal and illegal, encouraged yet discouraged, tightly regulated yet easily available” (Zuger, 2011, p. D1).Zuger, A. (2011, June 14). A general in the drug war.
New York Times
, p. D1.
Many prescription drug abusers use drugs obtained from their own prescriptions or from prescriptions of friends or relatives.
© Thinkstock
Most prescription drug abusers have their own prescriptions or obtain their drugs from friends, acquaintances, or relatives who have their own prescriptions. Whatever the source, some of these prescriptions are obtained legitimately—for actual medical conditions—and then abused, and some are obtained after feigning a medical condition. Many experts fault physicians for overprescribing painkillers and other prescription drugs.
Prescription drug abuse is thought to be growing for two reasons (National Institute on Drug Abuse, 2005).National Institute on Drug Abuse. (2005).
Prescription drugs: Abuse and addiction
. Washington, DC: Author. First, physicians’ prescriptions for painkillers and other drugs continue to rise, creating a greater supply of prescription drugs that can be abused. Second, online pharmacies and pain clinics have made it easier to obtain prescription drugs, with or without an actual prescription.
The
Note 7.14 "Applying Social Research"
box discusses the roots of adolescent prescription drug abuse in family and school factors. The importance of these factors reinforces the sociological view that the origins of drug use often lie beyond the individual and in the social environment.
Applying Social Research
Prescription Drug Abuse by Adolescents
Despite the importance of prescription drug abuse, social science research on its causes is relatively sparse. In one of the first studies to examine the social origins of adolescent prescription drug abuse, sociologist Jason A. Ford analyzed data on adolescents in the national survey conducted by the Substance Abuse and Mental Health Services Administration that is discussed elsewhere in this chapter. Drawing on the large body of work that attributes drug use in part to weak social bonds, Ford reasoned that prescription drug abuse should be higher among adolescents who have weaker bonds to their parents and also weaker bonds to their schools.
For his measure of parental bonds, Ford used several questions that asked adolescents about their relationship with their parents, including whether parents feel proud of them and praise them for doing a good job, and whether their parents help them with their homework and limit their time out with friends on a school night. For his measure of school bonds, he used several questions that asked adolescents such things as whether they liked going to school and whether they found their schooling meaningful and important. His measure of prescription drug abuse relied on the adolescents’ self-reports of whether they had used any prescription drug for nonmedical purposes in the past year.
Controlling for gender, race, and other factors, Ford found support for his hypotheses: prescription drug abuse was higher among adolescents with weaker bonds to their parents and also weaker bonds to their schools.
These results have important implications for efforts to reduce prescription drug abuse by adolescents. They suggest that efforts by our society to strengthen families and to improve our schools may well have a significant, beneficial side-effect: lower prescription drug abuse by adolescents.
Source:
Ford, 2009Ford, J. A. (2009). Nonmedical Prescription Drug Use Among Adolescents: The Influence of Bonds to Family and School.
Youth & Society, 40
(3), 336–352.
KEY TAKEAWAYS
-
The distinction between legal drugs and illegal drugs has no logical basis; legal drugs cause much more harm than illegal drugs.
-
Alcohol and tobacco kill more than 500,000 Americans annually. Binge drinking on campuses results in accidents and assaults involving several hundred thousand college students annually.
-
Marijuana is by far the most commonly used illegal drug. The low prevalence of other illegal drugs still amounts to millions of people using these drugs annually.
FOR YOUR REVIEW
-
Do you agree or disagree that the distinction between legal drugs and illegal drugs is not logical? Explain your answer.
-
Do you agree that binge drinking is a problem that campuses should address, or do you think that it’s a relatively harmless activity that lets students have some fun? Explain your answer.


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cultural appropriation
-
claiming or using elements of another culture in an inappropriate way.
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cultural ecology
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how humans develop culture as an adaptation to various environments.
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cultural evolutionism
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the study of the origins of human cultural forms and how those forms have changed over long periods of time.
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cultural frames
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patterned, shared ways of interpreting situations.
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cultural materialism
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an evolutionary approach that identifies technology and economic factors as fundamental aspects of culture, molding other features of culture such as family life, religion, and politics.
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cultural practices
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routine or habitual forms of behavior.
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cultural role
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a conventionalized position in a particular context or situation.
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culture
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the whole way of life of a society, combining material objects, technologies, social relationships, everyday practices, deeply held values, and shared ideas.
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diffusion
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in an anthropological context, the spread of material objects, practices, and ideas among cultures in complex relations of trade, migration, and conquest.
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friction
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occurs when two or more elements of culture come into conflict, resulting in alteration or replacement of those elements.
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functionalism
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a form of analysis that focuses on the contemporary purposes of culture.
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historical particularism
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an approach to cultural change that describes the combination of internal and external factors that shapes the unique historical trajectory of each culture.
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ideology
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a model that depicts how a social realm operates or should operate. An ideology identifies the entities, roles, behaviors, relationships, and processes in a particular realm as well as the rationality behind the whole system.
-
innovation
-
the slight alteration of an existing element of culture, such as a new style of dress or dance.
-
intellectual property
-
material and nonmaterial products of an individual or group that are protected by national and international laws and cannot be used for profit by others without attribution or compensation.
-
invention
-
the independent creation of a new element of culture, such as a new technology, religion, or political form.
-
material culture
-
objects made or used by humans, such as buildings, tools, clothing, household items, and art.
-
norm
-
the cultural expectations, including behaviors and attributes, that are associated with a cultural role.
-
ontological anthropology
-
an approach that explores how culture constructs our social and natural realities, what we consider real, and how we act on those assumptions. Reaching beyond human realities, ontological anthropology also attempts to include nonhuman perspectives, relationships, and forms of communication.
-
ontology
-
the study of the nature of existence.
-
rite of passage
-
a ritual that moves a person or group of people from one social category to another, often more highly valued one. Examples of rites of passage include naming ceremonies, initiations, weddings, and funerals.
-
ritual
-
repeated, patterned action conventionally associated with a particular meaning, often incorporating symbolic objects and actions.
-
social structure
-
the organizational framework for a particular realm of culture, such as the family, the economy, or the political system. Social structures combine material culture with practices and ideas.
-
structural functionalism
-
a form of analysis that describes how various aspects of culture fit together and contribute to the integrated whole of culture.
-
structuralism
-
the study of culture as a system of symbolic categories embedded in the myths, religion, kinship, and other realms of a culture.
-
symbol
-
an object, image, or gesture conventionally associated with a particular meaning.
-
technology
-
specialized knowledge or skills required to produce objects of material culture.
-
unilineal evolution
-
the idea that all cultures pass through a single set of developmental stages.
-
values
-
cultural notions about what is good, true, correct, appropriate, or beautiful.
-
worldview
-
a very broad ideology that shapes how the members of a culture generally view the world and their place in it. Worldviews tend to span several realms, including religion, economics, and politics.


11.3.7: Seizures
A seizure is disorder in which there is increased electrical activity of the brain. There are a variety of causes of seizures, such as head injury, low blood sugar, a heat-related injury, medical conditions, or poisonings (American Heart Association, 2011). In some types of seizures, the person has uncontrollable muscle movements. Tonic– clonic seizures have two phases: tonic and clonic. In the tonic phase, the person’s muscles contract and spasm. In the clonic phase, the person has repeated muscle movements, and their arms, legs, and torso may jerk violently.
Signs of a seizure:
Signs of a seizure depend on the type of seizure disorder the patient has. Home Health Aides/Personal Care Aides may notice:
- Suddenly falling or dropping from a seated or standing position
- Loss of muscle control
- Repeated blinking of the eyes, smacking of the lips, or repeated swallowing
- The person is not able to follow commands
- Inability to swallow
- Drooling
- Repeated contractions and movements of the arms, legs, or torso
- Shaking or jerking of the body
- The person stops responding
What to do:
If a patient has a seizure, it is important to obtain medical help immediately. Remember to never put anything in the person’s mouth during a seizure and never try to hold them down. The Home Health Aide/Personal Care Aide’s job during a seizure is to contact emergency medical services and to try to protect the patient from injury.
- Never leave a person during a seizure.
- Immediately call 911.
- Note the time the seizure began. Provide this information to 911.
- Place the patient in a comfortable position. Keep their head face up so they can breathe.
- Loosen any tight clothing.
- If possible, place a pillow, blanket, or towel under the patient’s head to prevent injury.
- Clear the area of any possible hazard for which the patient could become injured.
- Never put anything, including fingers, in the patient‘s mouth during a seizure.
- If they begin to vomit, roll them onto their side. Make sure their mouth is not obstructed.
- Never try to hold a patient down while they are having a seizure.
- Keep the area clear of objects and people.
- Do not give the patient food or fluid.
- Note the time when the seizure is over. Check for adequate breathing and pulse.
- If the person stops breathing or no longer has a pulse, perform CPR if trained to do so . If not trained in CPR, perform hands-only CPR.
- Inform a supervisor as soon as possible about the incident.
- Document the seizure and all steps taken to provide care.
True or False
1. EMS should be activated if a person is having a seizure. True or False? ________
2. A person should never put any objects or fingers inside a person’s mouth while they are having a seizure. True or False? ________
3. Never restrain a person during a seizure. True or False? ________
4. It is important to time when the seizure starts and stops. True or False? ________
5. All furniture and other dangerous objects should be removed from the area while a person is having a seizure to prevent any injury. True or False? ________
- Answer
-
1. True
2. True
3. True
4. True
5. True
FEEDBACK:
1. Emergency medical services should be contacted as soon as a person has a seizure. The person needs medical attention.
2. Never put objects or fingers inside a person’s mouth during a seizure. They will likely bite down although they will not be able to help it.
3. A person having a seizure should never be restrained. Rapid and repeated muscle contractions and jerky movements are common during a seizure. Restraining a person while they are having a seizure can cause them serious injury.
4. The HHA/PCA should time when the seizure starts and stops and provide this information to emergency medical services and the healthcare team. This will help give important information about the severity of the seizure.
5. After contacting emergency services the most important thing the HHA/PCA can do for a person during a seizure is to protect them from injury. Removing furniture, dangerous objects, and people from the area will help prevent further injury to the person having the seizure.


17.1: Introduction
Introduction:
Our genetic information is coded within the macromolecule known as deoxyribonucleic acid (DNA). DNA belongs to a class of organic molecules called nucleic acids . The building block, or monomer, of all nucleic acids is a structure called a nucleotide. A nucleotide has three parts: phosphate , deoxyribose sugar , and a nitrogen base .
There are four different nucleotides that make up a DNA molecule, each differing only in the type of nitrogenous base. These include adenine (A), thymine (T), cytosine (C), and guanine (G), often indicated by their first letters only.
James Watson and Francis Crick discovered the three-dimensional shape of DNA in the early 1950s. The shape, which they described as a double helix, has the shape of a twisted ladder.
The Genetic Code:
Think of the four nucleotides that make up DNA as the letters of an alphabet. To spell out a word (in this case an amino acid) three “letters” from our alphabet are required. Since only about 20 amino acids make up all the proteins, having a four-letter alphabet is more than sufficient to spell out the 20 “words” (see the calculations that follow). The genetic code is universal (almost) for all living things. What this means is that the triplet code spells the same amino acid in different organisms, from dolphins to plants to bacteria!
| Sequence of Nucleotides | # Amino Acids Coded |
|---|---|
| one | 4 1 = 4 (not enough) |
| two | 4 2 =16 (not enough) |
| three | 4 3 =64 (more than enough) |
The Gene Concept:
Think of a gene as a segment of DNA on a chromosome that codes for a series of amino acids that when linked together makes up what is known as a polypeptide . Polypeptides are then folded into complex three-dimensional shapes that become functional proteins.
The Central Dogma:
All organisms use the same fundamental mechanism for gene expression.
DNA → RNA → Polypeptide → Protein
Protein Synthesis:
Protein synthesis is a two-step process.
DNA —(transcription)→ RNA —(translation)→ Polypeptide
Transcription happens when the information from the DNA template is transcribed onto another form of nucleic acid known as ribonucleic acid or RNA (actually messenger RNA).
Translation happens when the information from the language of nucleic acid is translated into the language of proteins.
Licenses and Attributions
CC licensed content, Original
- Biology Labs. Authored by: Wendy Riggs. Provided by: College of the Redwoods. Located at: http://www.redwoods.edu . License: CC BY: Attribution
CC licensed content, Shared previously
- 0322 DNA Nucleotides. Provided by: OpenStax. Located at: http://cnx.org/content/col11496/1.6 . License: CC BY: Attribution
- Central Dogma of Molecular Biochemistry with Enzymes. Authored by: Dhorspool. Located at: https://commons.wikimedia.org/wiki/File:Central_Dogma_of_Molecular_Biochemistry_with_Enzymes.jpg . License: CC BY-SA: Attribution-ShareAlike
Public domain content
- The completed chart of the genetic code. Provided by: National Institutes of Health. Located at: http://history.nih.gov/exhibits/nirenberg/HS5_cracked.htm . License: Public Domain: No Known Copyright


34.2: Digestive Systems - Herbivores, Omnivores, and Carnivores
- Differentiate among herbivores, omnivores, and carnivores
Herbivores, Omnivores, and Carnivores
Herbivores are animals whose primary food source is plant-based. Examples of herbivores include vertebrates like deer, koalas, and some bird species, as well as invertebrates such as crickets and caterpillars. These animals have evolved digestive systems capable of digesting large amounts of plant material. The plants are high in fiber and starch, which provide the main energy source in their diet. Since some parts of plant materials, such as cellulose, are hard to digest, the digestive tract of herbivores is adapted so that food may be digested properly. Many large herbivores have symbiotic bacteria within their guts to assist with the breakdown of cellulose. They have long and complex digestive tracts to allow enough space and time for microbial fermentation to occur. Herbivores can be further classified into frugivores (fruit-eaters), granivores (seed eaters), nectivores (nectar feeders), and folivores (leaf eaters).
Omnivores are animals that eat both plant- and animal- derived food. Although the Latin term omnivore literally means “eater of everything”, omnivores cannot really eat everything that other animals eat. They can only eat things that are moderately easy to acquire while being moderately nutritious. For example, most omnivores cannot live by grazing, nor are they able to eat some hard-shelled animals or successfully hunt large or fast prey. Humans, bears, and chickens are examples of vertebrate omnivores; invertebrate omnivores include cockroaches and crayfish.
 The word carnivore is derived from Latin and means “meat eater.” Wild cats, such as lions and tigers, are examples of vertebrate carnivores, as are snakes and sharks, while invertebrate carnivores include sea stars, spiders, and ladybugs. Obligate carnivores are those that rely entirely on animal flesh to obtain their nutrients; examples of obligate carnivores are members of the cat family. Facultative carnivores are those that also eat non-animal food in addition to animal food. Note that there is no clear line that differentiates facultative carnivores from omnivores; dogs would be considered facultative carnivores.
Key Points
- Herbivores are those animals, such as deer and koalas, that only eat plant material.
- Omnivores are those animals, such as bears and humans, that can eat a variety of food sources, but tend to prefer one type to another.
- While most carnivores, such as cats, eat only meat, facultative carnivores, such as dogs, behave more like omnivores as they can eat plant matter along with meat.
- Facultative carnivores can eat meat as well as plant material while obligate carnivores eat meat all the time.
Key Terms
- omnivore : an animal which is able to consume both plants (like a herbivore) and meat (like a carnivore)
- obligate carnivore : an animal that necessarily subsists on a diet consisting mainly of meat because it does not possess the physiology to digest vegetable matter
- herbivore : any animal that eats only vegetation (i.e. that eats no meat)
- carnivore : any animal that eats meat as the main part of its diet


6.6: Long Run Investment Decisions and Cost Functions
It is possible to also develop long run cost functions in which the infrastructure itself may be changed to maximize net present value. In particular, rather than incur the high costs of congestion in high usage situations (as in Figure 6.3.1), an infrastructure manager might add capacity as rehabilitation investments are made.
The long run total cost curve is the lower cost envelope of all possible short run total cost options. Figure 6.6.1 illustrates the situation in which two possible infrastructure capacity options exist (which might represent different size components, an additional floor on a parking garage or an additional lane of roadway capacity). There is a usage point (\(q_b\)) in Figure 6.6.1 at which it is desirable to shift from option 1 to the larger capacity option 2. The long run average total cost has a significant turn at this usage breakpoint, with scale economies beginning again! The long run marginal cost curve has a discontinuity at the breakpoint. With lower demand (demand curve \(D\)), the smaller option has lower costs, but with higher demand (demand curve \(D’\)), the larger option 2 is more desirable.


16.11: Tutorials- Windows Movie Maker
Windows Essentials : This link will take you to an online site to help you use Movie Maker in Windows 7.
Windows Live Movie Maker Training : Or search for another version of the Windows Movie Maker Tutorials by using the “Applications” drop-down box HERE .
Download Windows Live Movie Maker HERE
Watch the Movie Maker Live Tutorial Here :
CC licensed content, Original
- Introduction to Computer Applications and Concepts . Authored by : Melissa Stange. Provided by : Lord Fairfax Community College. Located at : http://www.lfcc.edu/ . License : CC BY: Attribution
All rights reserved content
- Windows Live Movie Maker Quick Tutorial. Provided by : PCMech. Located at : https://www.youtube.com/watch?v=vh82WqBQ_2c&feature=youtu.be . License : Other . License Terms : Standard YouTube License


2.4: Current and Past Health
Understanding the client’s current and past health is important and may provide an explanation or rationale for the client’s current health status as illustrated in Figure 2.5 . Furthermore, these data can provide insight into health promotion needs and co-morbidities. It is helpful to understand the current and past health profiles before assessing other aspects of health, as the information will inform subsequent questions.
Your questions should also be based on the client’s response to the previous question.
As you develop your clinical judgment, which comes with practice, you will become more astute about which questions are appropriate and how to frame the questions. Table 2.4 provides sample questions for assessing current and past health, but other questions may arise that you may need to ask depending the client’s main health needs and their responses.
| Health Items | Questions and Statements | Considerations |
|---|---|---|
|
Current health
|
Probes
|
Although the client may not have made the connection, other health issues are sometimes related to their main health need. For example, they may report a fever in addition to an earache. |
|
Childhood illnesses
Type, timing, treatment, hospitalizations, complications, disability |
|
The probing questions may be more important to ask when the illnesses may impact the client later in life. |
|
Chronic illnesses
Type, timing, impact, treatment, hospitalizations, complications, disability |
Probes
|
Chronic illnesses can significantly impact a client’s life both physically and psychosocially. |
|
Acute illnesses, accidents, or injuries
Type, timing, treatment, hospitalizations, complications, disability |
Probes
|
Falls are an increasing health issue as a person ages or if they are taking several medications. This is partly related to decreases in muscle strength and balance and multimorbidity. It is important to assess the client’s risk for falls and fall prevention. Check out the Registered Nurses’ Association of Ontario (2017) best practice guideline: Preventing Falls and Reducing Injury from Falls |
|
Obstetrical health
Number of pregnancies, full-term deliveries, pre-term deliveries, number of living children, fertility treatments, miscarriages, abortions, and other data related to current or past pregnancy |
|
These questions do not apply to all clients. Additionally, you should be aware that the feelings about pregnancy can be complex and may not always be happy. |
The parents or a care partner are often present during an assessment of an infant or child. The adult child or care partner are sometimes present during an assessment of an older adult, particularly if the client has an acute or chronic illness, or a cognitive impairment or developmental delay. Care partners are important advocates in care planning. Thus, a family-centred approach can help you assess the client, as well as the level of caregiver burden and the need for additional resources.
Take Action
In addition to a comprehensive assessment, you should engage in health promotion discussions about a client’s current and past health. For example, this may include helping the client to address any resolved issues associated with chronic and acute illnesses. Additionally, you should consider how the client can develop control over, and improve their physical, mental, and social well-being. You should assess and discuss with them their social and personal resources to do so. Also, evaluate and intervene with critical findings related to current and past health that include anything that puts the client’s life at risk .
Test Yourself
Query \(\PageIndex{1}\)


15.12: Chapter 13
Your Turn
13.1
1. 46 in
13.2
1. 34 scales
13.3
1. 1.618
13.4
1. 1.25, which is close to a golden rectangle
13.5
1. 210 gal
13.6
1. 1,050,000 gal
13.7
1. 9,828 million gal of water
13.8
1. 15.8 kW
13.9
1. $14.18
13.10
1. $0.06
13.11
1. 288 kW
13.12
1. 1.8 mg in 200 mL
13.13
1. 6 pills
13.14
1. 42 mg
13.15
1. 13 mL
13.16
1.  G, G
#
, A, A
#
, B, C, C
#
, D, D
#
, E, F, F
#
13.21
1. 83 Hz
13.22
1. 10 games
2. 66 games
3. 300 games
13.23
1. 4 games
2. 11 games
3. 24 games
Check Your Understanding
1. 1.618
2. 1, 1, 2, 3, 5, 8, 13, 21, 34, 55
3. A rectangle whose length divided by the width is approximately equal to \(\mathit{ϕ}\) or 1.618.
4. \(1\,{\rm{kW}} = 1{,}000\,{\rm{watts}}\)
5. 100 gal
6. 33 1/3 hours
7. 17 hours
8. medicine dosage required, weight of drug by volume
9.
b
Research on coronavirus vaccines began approximately 10 years before the COVID-19 pandemic hit the world.
10. Mathematical modeling is a graphical representation of a behavior, such as exposure to a virus. It can be helpful in mapping contract tracing with virus exposure during a pandemic.
11. Frequency is a static measured value, whereas pitch is subjective.
12. higher
13. 20–20,000 Hz
14. increase
15. 0 dB
16. 20–17,000Hz
17. It doubles.
18. Data analytics is used in sports to analyze data on team’s players, potential recruits, opposing teams, and opposing players. This helps to find patterns and make predictions for future results.
19. Soccer (football)
20. \(n\left( {n - 1} \right)/2\)
21. \(n - 1\)


11.2: Ester Formation and Waxes
- Understand how esters are made.
- Identify the molecules used to make waxes.
- Describe the primary biological function of waxes.
Esterification
Esters can be prepared by esterification, a reaction in which a carboxylic acid and an alcohol, heated in the presence of an acid catalyst, form an ester and water through a dehydration followed by condensation reaction.
The reaction is reversible. As a specific example of an esterification reaction, butyl acetate can be made from acetic acid and 1-butanol.
Waxes
Lipid waxes are esters of one long-chain fatty acid with one unbranched long-chain alcohol containing 14 to 30 C′s per chain. For example, m yricyl palmitate found in beeswax is the ester of palmitic acid and myricyl alcohol.
Figure \(\PageIndex{1}\): palmitic acid and myricyl alcohol gives myricyl palmitate in beeswax
Figure \(\PageIndex{2}\): A wax ester - Myricyl palmitate
Waxes form a protective and waterproof coating on leaves, fruits, and stems of plants and on the skin, fur, and feathers of animals. Plant waxes on the surfaces of leaves, stems, flowers, and fruits protect the plant from dehydration and invasion by harmful microorganisms. In animals the waxes serve as protective coatings, keeping the surfaces of feathers, skin, and hair pliable, water repellent and buoyant. In fact, if the waxy coating on the feathers of a water bird is dissolved as a result of the bird swimming in an oil slick, the feathers become wet and heavy, and the bird, unable to maintain its buoyancy, drowns. Some microorganisms use waxes as energy storage molecules.
Some of the most common lipid waxes are listed in Table 11.2.1. These include beeswax obtained from the honeycomb, carnauba wax from palm trees, jojoba wax from jojoba bushes, and spermaceti obtained from the head and cavity of sperm whales. Beeswax and carnauba wax are used as protective coating on cars, furniture, floors, etc. Jojoba wax and spermaceti are used to make candles and cosmetics. A mixture of waxes obtained from wool is used in lotions for face and skin softening.
| Wax name | Condensed formula | Source |
|---|---|---|
| Beeswax |
|
Honeycomb |
| Carnauba wax |
|
Palm tree |
| Jojoba wax |
|
Jojoba bush |
| Spermaceti |
|
Sperm whale |
Petroleum Waxes and Earwax
Petroleum-derived waxes or paraffin are also called waxes but they are not esters, they are mixtures of long-chain hydrocarbons. Earwax is a mixture of esters of glycerol, esters of cholesterol, phospholipids, etc. from dead skin and from secretions of cerumen glands. Like other lipid waxes, it protects the ear canal against bacteria, fungi, and water. Excess earwax can cause blockage in the ear canal and hearing loss.
Summary
Esters are made by the reaction of a carboxylic acid with an alcohol, a process that is called esterification. Waxes are formed from long chain fatty acids and long chain alcohols.


6.1: Light Speed- Limit on Casualty
no signal reaches us faster than light
Signal Sun with super speed?
Nine-year-old Meredith waves her toy magician’s wand and shouts, "Sun is exploding right now!" Is she right? We have no way on Earth of knowing - at least not for a while. Sun lies 150,000 million meters from Earth. Therefore it will take 150,000 million meters of light-travel time for the first light flash from the explosion to reach Signal Sun with super speed? us. This equals 500 seconds - 8 minutes and 20 seconds. We will just have to wait and see if Meredith is correct... 1
When 8 minutes and 20 seconds pass, we have evidence that Meredith was mistaken: Looking through our special dark glasses, we see no exploding Sun.
But Meredith’s wand has started us thinking. What in the laws of nature prohibits the wave of her wand from being the signal for Sun to explode at that same instant? Or - more reasonably, given the awesome event - what prevents Meredith from having instantaneous warning, so that she raises her wand simultaneously with Sun’s explosion in order to give us (in light of later developments) a false impression of her power?
No, just speed of light
Both questions have the same answer: "The speed of light." Whatever her powers, Meredith cannot affect Sun in less than 500 seconds; neither can a warning signal reach us from Sun in less time than that. All during that intervening 500 seconds we would see the accustomed round shape of Sun, apparently healthy as ever. 2
More generally, one event cannot cause another when their spatial separation is greater than the distance light can travel in the time between these events. Light speed sets a limit on causality. No known physical process can overcome this limit: not gravity, not some other field, not a zooming particle of any kind. "Spacetime interval" quantifies this limit on causality. Interval between far-away events - unlike distance between far-away points - can be zero. In this and other ways the spacetime geometry of the real world differs fundamentally from the space geometry of Euclid’s 2300 year-old textbook.
1 Signal Sun with super speed?
2 No, just speed of light