State of the Environment

2001

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Land Theme Report

Australia State of the Environment Report 2001 (Theme Report)
Prepared by: Ann Hamblin, Bureau of Rural Sciences, Authors
Published by CSIRO on behalf of the Department of the Environment and Heritage, 2001
ISBN 0 643 06748 5

Soil and land pollution (continued)

Condition (continued)

Residues in foods: what is the record? [L Indicator 6.7]

In 1961, the Australian government established a program to monitor the presence of residues in certain agricultural and veterinary chemicals in meat products. Since then the National Residue Survey (NRS) has expanded and now undertakes testing on a large number of residues and contaminants in a range of animal and plant food commodities. By 1999, 16 animal, 14 plant and selected fishery and aquaculture products were being monitored on a regular basis (Table 36). These monitoring and surveillance programs are funded by industry, and are primarily aimed at providing information for trade, not for environmental or health purposes. Frequent audit by major trade partners assures the quality and accuracy of the NRS programs and their data are therefore available as a surrogate measure of chemical residues that could be transmitted through food chain to organisms other than humans.

Residues and contaminant levels in agricultural products do not necessarily reflect the absence or level of residues that may be in soil, native biota or in water, because of diverse spatial distribution and management practices of agricultural and fisheries production. In addition the complexity of many of the metabolic pathways involved can impact on the temporal presence of the chemicals and their breakdown products. However, the continuity of the record, the scale of monitoring, and the number of products and compounds tested make the NRS data an indirect environmental indicator, in the absence of direct monitoring programs of off-target environments, such as soil, native fauna and flora, and water. Ideally a national environmental monitoring program is needed with a database that can provide evidence of the degree and extent of environmental impact from agrichemical usage.

Selected food commodities are analysed for a large number of possible contaminants as appropriate (Table 36).

Table 36: Chemicals tested by the National Residue Survey.A
Animals Plants Honey
Hormones (4) Organochlorines (5-10) Organochlorines (16)
[beta]-agonists (3-6) Organophosphates (6) Organophosphates (11)
Androgens (3) Growth regulators (1-5) Synthetic pyrethroids (9)
Organochlorines (4-14) Synthetic pyrethroids (6) Heavy metals (5)
Organophosphates (3-14) Carbamates (1-4)  
Synthetic pyrethroids (7) Preharvest fungicides (2-15)  
Benzoyl ureas (4) Postharvest fungicides (6)  
Heavy metals (7) Heavy metals (3)  
Antibiotics (15) Scald inhibitors (2)  
Anthelmintics (12)    

A Numbers in parentheses refer to the number of chemicals tested in each category.

NRS results reported against maximum residue levels (MRLs) for agricultural and veterinary chemicals and maximum permitted concentrations (MPCs) for metals and contaminants established in the Australian Food Standards Code show very few detectable levels against those permitted.

The NRS has continued to monitor meat samples for organochlorines, such as DDT and dieldrin, that have been withdrawn for more than a decade, but which have long-lived persistence and derivatives in the environment. The program also monitors meat samples from wild animal meats, derived from a wide range of farming, rangeland and forested environments as well as animals from more intensive agricultural areas. Over the period 1994-1999, these tests have included water buffalo (360 specimens), possum (373), camel (564), emu (771), feral pig (3120), feral goat (4120), and kangaroo (4065). In none of these has there been any detectable level of residue.

Figure 74: Percentage samples analysed that did not exceed the Maximum Residue Level (MRL) or Maximum Permitted Concentration Level (MPC) as percentages of total number of samples.

Figure 74: Percentage samples analysed that did not exceed the Maximum Residue Level (MRL) or Maximum Permitted Concentration Level (MPC) as percentages of total number of samples

Source: National Office of Food Safety (1999)

The NRS has monitored honey for a number of years. Australian honey producers set hives in a wide range of environments throughout the agricultural zone where a large range of pesticides are frequently used, for examples close to horticultural orchards as well as within open woodland and forests; such sites are often close to open waterways. A total of 7449 analyses were performed on 406 samples in 1998-99, in which there were no detectable residues (National Office of Food Safety 1999).

Dealing with pesticide containers

The association of chemical companies and distributors called Avcare Ltd was incorporated in 1982. Together with a number of participating organisations, it has been proactive in developing a professional attitude to safe agricultural and veterinary chemical handling in all spheres of operation. These participating organisations include: The Australian Local Government Association, National Farmers Federation, Chemcert (farm operators accreditation), Veterinary Manufacturers and Distributors Association, DrumMUSTER, ChemClear, Herbicide resistance management strategy and AgSAFE (manufacturers and distributors accreditation).

Avcare's main activities aim to encourage rural industries to work in a co-regulated and self-disciplined approach to chemical use. This includes:

Industry Waste Reduction Scheme

The agricultural and veterinary chemical industry Waste Reduction Scheme has two objectives:

The drumMUSTER program

The national drumMUSTER program aims to collect and recycle empty, cleaned, non-returnable agrichemical containers. Managed by AgSafe for the National Farmers Federation, Avcare Ltd, the Australian Local Government Association, and the Veterinary Manufacturers and Distributors, it is funded by a levy on crop protection and farm animal health products sold in non-returnable containers of over 1 kg in content. The scheme focuses on handler education and safety and good environmental standards. Rinsing and collection procedures are given out in brochures at point-of-sale.

By 2001 the target is to:

A recent study on farmers' behaviour in rinsing chemical containers found that those who do not are more likely to be livestock producers, to have large farms and to have tertiary education (Turrell and McGuffog 1997). This was an unexpected finding, and demonstrates that better management practices are not necessarily related to formal educational level.

To ensure that stocks of unused farm chemicals are safely disposed of, the agricultural industry agreed to institute ChemClear, a continuing program for the regular collection of registered farm chemicals that are otherwise non-returnable. ChemClear will begin after ChemCollect has finished in each State. It is a joint initiative of Avcare Ltd, the Veterinary Manufacturers and Distributors Association and the National Farmers' Federation.

These programs are good examples of the industry's increasing recognition of its 'cradle to grave' responsibility for its products.

Typical chemical containers collected in the drumMUSTER program

Typical chemical containers collected in the drumMUSTER program.

Source: AVCARE (unpublished data)

Agrichemical Reviews, 1995-2001

As in many countries, organochlorine chemicals such as DDT, developed in the 1940s, were initially used to control malarial mosquitoes and other insect pests such as termites and Argentine ants. Until the 1980s these organochlorines were used in agricultural and horticultural situations to control many pests. Concern for their effects on human and environmental health led to phasing out of organochlorines, except for specific local use under permit, during the 1980s.

The National Registration Authority (NRA) was established in 1995, and inherited over 5000 chemical registrations from the States and Territories. Some of these were issued in the 1950s. For example Parathion was developed by Bayer in 1940 and has been used in Australia for over 50 years. Many regulations have not changed since first registration, although there is now more data on the toxicology, environmental effects, safer alternatives and site-specific behaviour for many chemicals than were available when they were first registered. A minority of chemicals have been withdrawn after review, but nearly all others are now subject to much more stringent regulations for use. Environmental concerns have triggered about half the reviews. Pesticide risk evaluation therefore uses sensitive aquatic and/or invertebrate organisms as 'model' or indicator organisms of environmental risk.

Table 37: Reviews of agricultural chemicals undertaken by the National Registration Authority.
Chemical and type Reason Review status
Glyphosate-herbicide Threat to frogs and tadpoles Completed 1996A
Atrazine-herbicide Groundwater and stream contamination Interim report 1997A
Mevinphos-OP insecticide Worker safety, human toxicity Interim report 1997A
Metham sodium, Dazomet, MITC-soil fumigants Worker safety, human toxicity Completed 1997A
Vinclozolin-systemic fungicide Human toxicity Completed 1997B
Chlorpropham-selective herbicide No MRLs established Completed 1997A
Tribufos-OP defoliant Worker safety, environmental impact from drift Completed 1998B
Macrocyclic lactones-endoparasite control in animals Worker safety, residues in food products Completed 1998A
Ethylene dibromide-soil fumigant Human toxicity Completed 1998B
(ethyl) Parathion-OP insecticide Worker safety (aerial sprays) Final report 1998A
Endosulfan-insecticide Toxicity to aquatic life forms Interim report 1998A
(methyl) Parathion-OP insecticide Toxicity to bees, aquatic organisms Interim report 1999A
Streptomycin/penicillin products and combinations-veterinary antibiotics Human health, residues in animal products Completed 1999B
Fenitrothion-locust and stored grain insecticide Toxicity to birds and beneficial insects Interim report 1999B
Chlorfenvinphos-insecticide for animal ectoparasites Worker safety, potential runoff impacting aquatic life forms Draft report 1999A
Monocrotophos-OP insecticide Human toxicity, worker safety Completed 2000B
Chlorpyrofos-OP insecticide Toxic to beneficial insects and fish, worker safety Draft review 2000A
Dichlorvos-OP insecticide Poisoning risk in workers Draft report 2000A

ARetained after revision of registration, reformulation, or labelling and/or restrictions on use (e.g. no aerial spraying, only in low volume, early morning, no wind, ground sprays etc.)
BWithdrawn, registration cancelled; Fenitrothion allowed under special licence for quarantine purposes in sealed containers.
OP Organophosphate.

Source: National Registration Authority (unpublished data).