Food and Nutrition

Chemical Hazards in Foods

Hazard is a biological, chemical or physical agent that is reasonably likely to cause illness or injury in the absence of its control. Hazards in food are categorized into three classes: biological hazards, chemical hazards and physical hazards.

Chemical hazard refers to any substance or chemical that can lead to health problem when it reaches inside the body either by ingestion or inhalation.

Chemical contamination can happen at any stage in food production and processing.  Chemicals can be helpful and are purposefully used with some foods, such as pesticides on fruits and vegetables.


Chemicals are not hazardous if properly used or controlled.  Potential risks to consumers increase when chemicals are not controlled or the recommended treatment rates are exceeded.

  1. The presence of a chemical may not always represent a hazard.
  2. The amount of the chemical may determine whether it is a hazard or not. Some may require exposure over prolonged periods to have a toxic effect.
  3. Regulatory limits are set for some of those contaminants.


Chemicals present in food are termed as chemical hazards when their level exceeds the limit of acceptance or levels that are hazardous to human. Contamination of foods by such chemicals can occur from various ways:

  1. Chemicals used during manufacturing process of food.
  2. Intentional use of chemicals E.g. Pesticides used for killing the pests and Veterinary drugs used for controlling pathogens in poultry, Cattles etc.
  3. Environmental source (Air, Soil, Water etc.)
  4. Addition of the food additives during production.


Chemical hazards in food


There are various chemical hazards that can occur in food and food products. Some of them are:

  1. Mycotoxins- Aflatoxin, Patulin
  2. Other toxins- Lectin, Tertodotoxin (Marine toxin)
  3. Chemicals used in food processing i.e. Processing induced chemicals- Ethyl carbamate, Acrylamide
  4. Contaminants form environment- Lead, Arsenic etc.
  5. Food additives-Food colors, Emulsifiers, preservatives.
  6. Veterinary Drug Residues.
  7. Pesticides- Azoxystrobin, Thiocarbamate etc.


Various types of Chemical hazards can be present in food. They can be classified into following categories:

  1. Naturally occurring chemicals.
  2. Intentionally added chemicals.
  3. Unintenionally or incidentially added chemicals.
  4. Food allergens

Implementation of Good Manufacturing Practices (GMPs) can prevent chemicals hazards in food.