Chemicals & food

Chemicals from natural and synthetic sources can be found in foods, and some have the potential to affect our health. Learn about some of these chemicals, how they get into food, and how to limit your exposure.

Find out which foods are more likely to cause illness and how best to handle them.
Learn more about vitamins and minerals found in foods.

How do chemicals get in our food?

Chemicals can be natural or man-made and can enter our food in several ways.

They may:

  • be found in the environment where food grows – for example, mercury is found naturally in seawater, and can be found at relatively high levels in some types of fish
  • leach into foods from packaging, such as bisphenol A (BPA) from some plastic packaging
  • be caused by food production and processing methods – for example, acrylamide forms when some foods are cooked at high temperatures, and agricultural chemical use can lead to residues in foods
  • be added illegally during production
  • accidentally enter the food supply – for example, when someone eats a wild animal that has consumed a poison like brodifacoum meant for other predators.

What danger do these chemicals pose?

Chemicals are regulated to minimise any risk to consumers. Residue monitoring programmes and diet surveys confirm New Zealand food remains safe.

Regulating and monitoring chemical residues in food

MPI is responsible for making sure that food produced and sold in New Zealand is safe and suitable to eat. We do this is by monitoring levels of residues, contaminants and other hazards in our food and setting food safety standards (including maximum levels) for these. MPI does this by:

  • regulating the use of certain chemicals, including agricultural compounds used in the production of food. Agricultural compounds must be registered and shown to be safe for use
  • monitoring chemical levels in specific foods through programmes like the National Chemical Residues Programme and the Food Residues Surveillance Programme
  • assessing New Zealanders' overall consumption of chemicals through the New Zealand Total Diet Study
  • requiring food producers to have food safety plans or programmes to minimise risk. We regularly audit these to ensure they're being followed.

Find out more

Who to contact

If you have questions about chemicals in food, email

Last reviewed: