TITLE : Chemical Residues in NSW Wildlife
DATE OF ENTRY: 7.4.1994
KEY WORDS : wildlife, residues,
SUMMARY : Wildlife in NSW has been shown to carry significant load of chemical residues. Chemicals detected include organo- chlorines, organo-phosphates and surfactants.
AUTHOR : Mariann Lloyd Smith
ISSUE : Effects of Pesticide Contamination on Wildlife
The effects of both organo-chlorine and organo-phosphate pesticides on wildlife are well documented in overseas scientific literature. The effects can range from acute toxicity and death to chronic reproductive effects such as `raptor pesticide syndrome'. Other chronic effects include lengthened courtship and delayed nesting or other behavioural disturbances such as reduced activity levels and intolerance to cold. Research has shown the adverse effect of organo- phosphates on the defence of breeding grounds in grouse or decreased activity levels and/or visual disturbances in quail and even the inadequate reaction to fear in young mallards. Any of these factors can lead to either the inability to breed successfully or to obtain food and may result in a range of other adverse effects which reduce species viability.
The work of Professor Louis Guillette Jr, reproductive endocrinologist, Uni of Florida provides a valauble flow on from the Wingspread Report 91 which sent out a alert from eco-toxicologists and wildlife researchers that the world's chemical production of oestrogen mimickers was affecting wildlife.
Chemicals such DDT, synthetic pyrethroids, triazine herbicides, detergent surfactants, heavy metals and soya products can disrupt the endocrine system of animals. Gillette's work basically confirmed that insidious broadscale contamination is impacting on significantly on wildlife. Gillette's and the Department of Fisheries work with Alligators in Florida and showed that in Lake Apopka 25-30% of male alligators had significant abnormalities of their penis.
Their production of oestrogen was above that of female alligators, their testosterone production was significantly decreased and they were incapable of reproducing. Surveys carried out later on the surrounding remaining population of black panthers found a significant number of male animals with some form of reproductive abnormality, undescended testicles, over production of oestrogen.
There are substantial datagaps in relation to wildlife toxicology, particularly for native Australian fauna. In discussion with the NSW EPA Centre for Environmental Toxicology, it was recommended that safety factors of at least 10 be included in any environmental health assessment based on overseas data.
CASE 1.
A Copy of the chemical analysis of a koala submitted by the Toxin Action Group 17.9.91, was received in July 1992.
A substantial response with more than one peak was detected. Components identified appeared to be compounds like trisdecanoic/tridecanoic acid or its derivatives. Little additional information was supplied
Decanoic acid has the potential to be a metabolite of the ingredients of a formulated fungicide (act.propicanozole, plus calcium dodecylphenyl sulphonate, fatty acid ester ethoxylate), a common pesticide routinely applied by air in the Coffs Harbour area. Yet, the koala was not examined for residues of propicanozole and any of its metabolites.
The data on this acid indicates it is not particularly toxic but for one aspect, that is, the acid can create intestinal hurry. A koala feeding on eucalyptus leaves can not afford intestinal hurry. It needs to retain its food in the gut to aid digestion. As the full autopsy report was never provided despite numerous requests, TAG was unable to assess whether any signs of 'intestinal hurry' were observed.
The detection of a wetting agent in this koala may indicate contamination of its food source and/or groundwater with surfactant type chemicals. As both the Coffs Harbour sewerage works and the airport have a potential for contamination with this group of chemicals and experience on the NSW Central coast have indicated such a possibility, we requested investigation of such a contamination possibility. None occurred.
CASE 2.
In 1991 there was the release by TAG of data originated from NPWS and Department Of Agriculture, showing Chlorpyrifos, an organo-phosphate had been detected in the eggs of Little Terns and Pelicans in 1990 sampling, from the Wallace Lake Colony, central coast of NSW:.
- - three eggs of Little Terns (0.06-0.36ppm),
- - one liver sample from Little Terns (0.02ppm)
- - one Pelican egg (0.5ppm)
No investigation of the results was ever carried out.
CASE 3.
While the dietary level in prey needed to produce critical egg shell thinning and decreased production in peregrine falcons has been calculated as approximately 1mg/kg, DDT and Dieldrin have been detected regularly in North Coast wildlife at disturbingly high levels. In the 1983-85 survey, jointly carried out by NPWS, SPCC and Department of Agriculture, samples of kookaburras, cormorants and magpies were found to contain over 90 mg/kg of total DDT load in body fat and one magpie carried a load of 375 mg/kg Dieldrin in its fats. Bandicoots tested showed up to 50mg of DDT per kg of fat and over 115 mg/kg of Dieldrin. In more recent testing in '89- 90, DDT was detected at 15-17 mg/kg (bodyfat) in the region's birds of prey.
A Sea Eagle found in the Coffs Creek area (1989) had Dieldrin levels of 26mg/kg, total DDT at 17mg/kg and 7.3mg/kg of Heptachlor Epoxide in unspecified sample. Both lead and cadmium were detected in its kidney tissue.
Similarly, an Osprey from the Grafton region (27.6.90) had total DDT levels of 14 mg/kg in fat with traces of dieldrin. Lead and cadmium were detected in liver samples.
CASE 4.
Analysis on four mouse samples from Gouldings Dip Lismore, and Websters Grass Dip were carried out by NSW Agriculture in October 93.
All 5 samples showed the presence of both DDT (0.12, 0.21, 0.41, 0.44 mg/kg) and its breakdown product DDE. (0.05, 0.05, 0.14, 0.19 mg/kg).
REFERENCES :
1. Laboratory Report WN92/0741, 29.6.92 NSW Regional Veterinary Laboratory.
2. Correspondence : Mr J.G Boulton Officer in Charge NSW Agriculture Regional Veterinary Laboratory, Wollongbar
3. NSW Department of Agriculture, Pesticide Analysis No. CP90/633-635 Re: Pelican Eggs, Little Tern - Wallace Lake Colony
4. North Coast Region NSW Agriculture, Pesticide Analysis No.93/322-CRL 93/50/2
5. The Gender Benders, Janet Raloff, Science News Vol 145, Jan 8 1994. (also reported ABC Green & Practical July 94, tape available)
6. Community Participation in Environmental Management, The Cattle Dip Site Model. John Craven, University of New England Northern Rivers, Faculty of Resource Science and Management. 1993
GEOGRAPHIC AREA : Aust. NSW
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