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.
All hazards are assessed and categorized into three groups: biological, chemical and physical hazards. A general definition of a hazard as related to food safety is conditions or contaminants that can cause illness or injury.Biological hazards include microorganisms such as bacteria, viruses, yeasts, molds and parasites. Some of these are pathogens or may produce toxins.A pathogenic microorganism causes disease and can vary in the degree of severity. Examples of biological hazards include Salmonella, E. coli and Clostridium botulinum.iological hazards include microorganisms such as bacteria, viruses, yeasts, molds and parasites. Some of these are pathogens or may produce toxins. A pathogenic microorganism causes disease and can vary in the degree of severity. Examples of biological hazards include Salmonella, E. coli and Clostridium botulinum.