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.Chemical hazards vary in the aspect of production they are related to. Some potential chemical hazards could be prior to a processor receiving product, such as the improper use of pesticides or antimicrobial residues. Others could be chemicals used on processing equipment such as oils used on equipment or sanitizers. Physical hazards include objects that are hard or sharp such as glass, metal, plastic, stones, pits, wood, or even bone. Physical hazards can lead to injuries such as choking, cuts, or broken teeth. Some foreign material in food products may not be a physical hazard but rather an undesirable foreign material such as hair, insects, or sand that are not likely to cause injuries.