07:40 PM ET 08/03/99

Some Chemical Exposure OK for Humans

By H. JOSEF HEBERT=

Associated Press Writer=

WASHINGTON (AP) _ Low-level exposure to chemicals that disrupt hormones won't necessarily lead to additional cancers or infertility, a scientific panel said Tuesday, stressing that more research is needed.

While it is clear that exposure to these chemicals at high concentrations can affect wildlife and human health, the National Academy of Sciences' 16-member research panel said, ``the extent of harm caused by exposure ... in concentrations that are common in the environment is debated.''

Far too little is understood about the possible harmful effects from low-level exposure to such chemicals, the panel said.

Environmentalists and numerous health experts have argued there is growing evidence that synthetic chemicals affect estrogen levels and even at low doses may lead to cancers, neurological problems and infertility.

These chemicals, called ``endocrine disrupters,'' are the subject of a massive screening process directed by the Environmental Protection Agency with as many 15,000 chemicals to be tested. The tests are being conducted mostly by industry.

The NAS panel's report said the current literature does not support an association between exposure to low levels of these chemicals and breast cancer or a variety of other hormonally sensitive cancers.

The scientists acknowledged there has been evidence of adverse reproductive and developmental effects in wildlife and laboratory animals because of exposure to endocrine disrupting chemicals. But it said that increases in male reproductive disorders in humans cannot be linked to the chemicals at doses found generally in the environment.

Similarly, the panel agreed there is ample evidence that fetal exposure to high doses of these chemicals _ such as exposure to high amounts of pesticides in fish or other foods _ have been found to hinder nervous system development in humans as well as birds and animals.

But the study said the data on the effects of these chemicals on human nervous system development at levels in the environment is insufficient to make a definitive conclusion.

In all these areas, the panel said additional studies are needed, especially on children whose mothers were exposed to such chemical agents during pregnancy.

``Determining the risks to humans from contact with these chemicals in the environment is difficult because ordinary exposure of these agents has not been routinely monitored, said Ernst Knobil, of the University of Texas and chairman of the panel.

But several scientists, including a member of the panel, said in interviews that the data on which the study was based is now two years old and that more recent research suggests a closer link between endocrine disrupting chemicals and human health.

There is a ``plausibility of human harm'' that cannot be ignored, Frederick vom Saal, a professor of biological sciences at the University of Missouri, said in a telephone interview.

Vom Saal, a member of the research panel, said the degree to which there is consensus on the effects of these chemicals at the molecular level on wildlife and on laboratory animals suggests the likelihood of impact on humans as well.

Peter deFur, an environmental biologist at the Virginia Commonwealth University, who reviewed the report, said more recent research not covered by the study implies ``a closer link to human health'' impacts than the study suggests. ``There is a tremendous amount of research activity going on a number of these questions,'' he said.

This page is maintained by

The Rivermouth Action Group Inc

E-mail: activist@rag.org.au

as a community service.