Organochlorines in Queensland

Possessing or using any of the following organochlorines (OCs) in Queensland is illegal:

• DDT
• Aldrin
• Endrin
• Chlordane
• Heptachlor
• Dieldrin
• HCB
• BHC.

The following OCs are not approved for use in Queensland:

• Lindane
• Methoxychlor.

Organochlorines are a risk to Australian agricultural produce

Persistent OCs remain in the environment for a long time after they have been used. If an animal ingests soil contaminated with OCs, the OCs are stored in the fat deposits of the animal. This means that there is a potential risk that the meat and milk products of cattle and other grazing animals will be contaminated with OCs.

Extraneous Residue Limits (ERLs) have been set to establish the maximum limits (or concentrations) of residues that are allowed in food. These international standards protect the health of consumers and ensure those involved in the food trade follow fair practices. An ERL is expressed in milligrams of the chemical per kilogram of the food (mg/kg).

It is very important that you maintain OC contaminants below the ERL or the levels set by major export markets. Detection of OC contaminants above accepted levels could affect access to overseas markets and have disastrous consequences for industries such as those involved with food-producing animals. In 1987, the US market was temporarily closed because of concerns over OC contamination.

Sources of organochlorine contamination

Persistent OC contaminants may still exist in areas where there was crop production when OCs were still approved for use. Crops on which OCs may have been used include:

• sugar cane
• cotton
• bananas
• tobacco
• apples
• pears
• potatoes.

In the past, you were also allowed to use OCs in cattle and sheep dips, in yards, on fence posts, on power/telephone poles and in buildings treated for termites. Some of these structures may still contain OC contaminants.

The Biosecurity Regulation 2016 adopts the contaminant standards for heavy metals, polychlorinated biphenyls and organochlorine chemicals from schedule 19 and schedule 21 of the Australia New Zealand Food Standards Code as the acceptable levels for contaminants in plant and animal food commodities.

Organochlorine contamination in animals

Most OC contamination in animals occurs when they ingest contaminated soil. The amount of soil consumed depends largely on the amount of grass cover. Contaminated soil can also be transferred to herbage by dust, raindrop splash or flooding.

Contamination of farm water supplies is rarely caused by run-off from contaminated soils as the contaminants are tightly bound to the sediment.