How long does marijuana stay in your system of you smoked it once? Someone who smokes occasionally-or for the first time-will  likely test positive for 1-3 days afterward, according to a review  by the  National Drug Court Institute (â¦ NDCI).ow long does marijuana stay in your system of you smoked it once? Someone who smokes occasionally-or for the first time-will  likely test positive for 1-3 days afterward, according to a review  by the  National Drug Court Institute (â¦ NDCI).
Chemical hazard. A chemical hazard is a type of occupational hazard caused by exposure to chemicals in the workplace. Exposure to chemicals in the workplace can cause acute or long-term detrimental health effects.
Chemical contamination. Chemical contaminants are chemicals toxic to plants and animals in waterways. The phrase 'chemical contamination' is used to indicate situations where chemicals are either present where they shouldnât be, or are at higher concentrations than they would naturally have occurred. Chemical contaminants can be found as organic and inorganic molecules in mass produced products used day to day by almost everybody.