1978 October: Birth deformities Sale, Yarram, Cairns. Pesticides: 2,4,5-T, 2,4-D

New Scientist 19 October 1978

Herbicides Under Suspicion in Australia – Brian Lee, Canberra

The herbicides 2,4-D and 2,4,5-T remain suspected by the Australian public of causing birth defects despite being cleared by two government inquiries. The inquiries were set up after what seemed like abnormally high numbers of babies born with deformities at Cairns in Northern Queensland and at Yarram some 2000 km to the south in Victoria. The herbicide 2,4,5-T is used extensively for spraying fields of sugar cane near Cairns, and use of both this herbicide and 2,4-D were suspected of causing the deformities at Yarram.

The federal National Health and Medical Research Council reported in June this year that it could find no substantial scientific evidence of a causal link between the use of 2,4,5-T and human birth defects. It also stated that “the use of 2,4-D is not producing any risk to human health”.

In its report, which was published late last month, the Victorian state government’s investigation into the birth defects at Yarram also failed to establish a statistical link between the use of 2,4,5-T and birth defects. However, no sooner had that report been published than a further group of birth deformities came to light at the Victorian town of Sale. In this case, four deformed babies were born at the same hospital between September and December last year. One had no brain, another spina bifida, the third underdeveloped internal organs, and the fourth a cleft palate. The mothers of all these babies lived in houses that faced a playing field that had been sprayed the previous January with a strong formulation of 2,4-D to control weeds. State Premier Dick Hamer announced last week that another inquiry will be held into these birth defects at Sale.

According to the National Health and Medical Research Council, Australia uses almost 2000 tonnes of 2,4-D and 250-300 tonnes of 2,4,5-T each year. Implicating or clearing these herbicides of causing the birth defects will be particularly difficult. At both Yarram and Cairns the basic statistics needed to determine whether the respective clusters of birth defects truly constituted epidemics were apparently just not available. At Yarram birth deformities were found in about 8 per cent of births, while at Cairns the figure was 6 per cent.