They are important for lung function, since their purpose is the exchange of oxygen and carbon dioxide. When the airways are blocked by a mucous plug, foreign object, or tumor, the alveoli are unable to fill with air and collapse of lung tissue can occur in the affected area.
Testing Positive for Marijuana Does Not Indicate Impairment Someone can test positive for marijuana days or even weeks after they last used it. by Dr. Carl Hart @drcarlhart. AAs Oregonians consider their vote on tax and regulation of marijuana, it is important for them to have access to sound information grounded in science.
â¢ and the Frequency of Use. The most popular drug test is a urine test. THC will test positive in a urine drug test within 2-5 hours of use. If you are a one time user or no more than a couple of times per month, you may test positive for 1-6 days after your last use.A moderate or weekly user may test positive for 7-13 days after their last use.f marijuana use is detected in a hair drug test then it would show up 7 days after use and for as long as 90 days. Hair tests can reliably detect chronic or daily use, but may not detect occasional use. It is doubtful that one time marijuana use would be detected on a hair drug test.