Managing the risks of chemicals and contaminants in animals

You can manage the risk of unacceptable chemical residues and contaminants by:

• using chemicals according to the instructions on the label or permit
• ensuring that agricultural inputs such as animal feed and fertilisers do not have levels of contaminants above acceptable levels.

Grazing animals should also be managed in a way that restricts access to contaminated land or other places such as rubbish tips where contaminants may be present.

Failure to manage the risks from such chemicals and contaminants may constitute a failure to meet your general biosecurity obligation (GBO) under the Biosecurity Act 2014. Your GBO obliges you to minimise biosecurity risks that concern human health, the environment, and the economy.

Biosecurity Queensland works with other government agencies to develop programs to monitor and manage the risks posed by chemical residues and contaminants.

Chemical residues

Residues of agricultural or veterinary chemicals can occur due to direct chemical treatment of the plant or animal from which the product is derived. Residues may also occur because there has been a chemical treatment of some other material that is then taken in by the plant or animal.

Residues in meat or milk can also result from indirect chemical exposure if animals are fed grain or forage that has been treated with a pesticide. Unacceptable chemical residue levels should not occur if approved label instructions or permit conditions are strictly observed when the chemical is used.

Contaminants

Contaminants can accumulate in animals:

• grazing on contaminated land sites
• having access to rubbish tips or industrial wastes
• when poor quality feed ingredients or fertilisers are used.

Certain plant toxins can also contaminate animals that feed on plants producing those substances. Unacceptable levels of contaminants can end up in food and animal feed products.

Examples of these contaminants include:

• persistent organochlorine pesticides, such as dieldrin, DDT or heptachlor
• heavy metals such as cadmium, lead or mercury
• naturally occurring toxins such as aflatoxins and alkaloids
• contaminants occurring after industrial processes, such as dioxins (which can also occur naturally).

Sometimes residues of chemicals and contaminants are below acceptable Australian levels but can still cause concern. Even minute levels of chemicals and contaminants can affect trade and affect market access to countries where different or lower standards apply.