Breast-milk Research Reveals Excessive Levels Of Pesticide
Wednesday January 18, 1995
Excessive levels of the pesticide heptachlor have been found in the breast milk of one-third of first-time mothers tested in a Melbourne study.
Heptachlor, from the group of organochlorides that includes DDT and dieldrin, is commonly used against termites in houses. Authorities have already acted on concerns about its longevity in the environment, with a ban to begin on 30 June.
The Royal Melbourne Institute of Technology’s Centre for Applied and Nutritional Toxicology studied 57 milk samples from 23 women from Cranbourne and Footscray.
Researchers Ms Diana Donohue and Ms Patricia Quinsey extracted fat from the milk samples and weighed babies to compare intakes of organochlorides.
One-third of the samples were positive to heptachlor, showing levels above the World Health Organisation’s acceptable daily intake, which is 0.1 micrograms per kilogram of body weight. Half were between 0.1 and 0.225 micrograms, the other half were above 0.225.
The study also found that every milk sample had traces of DDT, which has been banned in Australia for several years.
However, the average level of DDT in mothers’ milk fat is below the WHO’s acceptable levels.
Ms Donohue said it was important to note that the WHO’s levels were conservative and applied to lifetime exposure, rather than just the time a baby is breastfed.
Despite the chemical residues, she was convinced that the benefits of breastfeeding outweighed the doubts.
“It’s the only balanced formula for babies,” she said. “It also contains antibodies against disease to give babies a head start.”
The National Registration Authority will deregister the last two of the main organochlorides, heptachlor and chlordane, on 30 June.
The vice-president of the Australian Environmental Pest Managers Association, Mr Peter Meadows, said there was no evidence of long-term health effects in humans from the “minute quantities” of heptachlor used to kill termites in houses.
“The Australian public is being denied a very safe and effective tool,” he said. The alternative, a phosphate called chlorpyrifos, would add $3000 to the cost of a house, he said.