Certain natural and manmade substances have some characteristics similar to estrogen and other hormones. Scientists are exploring the theory that exposure to low levels of these substances may impact the endocrine (hormone) system and thereby affect the reproductive or developmental health of wildlife or humans.

This information sheet summarizes key findings from studies on alkylphenols (APs) and alkylphenol ethoxylates (APEs) related to this theory. APs are chemical compounds used primarily to manufacture APEs, which have been used widely for more than 50 years as cleaning agents or surfactants. Based on available research:

Numerous studies show that normal exposure to APs and APEs does not pose a significant risk to human health.

No direct link has been established between exposure to industrial chemicals in the environment and any harmful effect on humans due to endocrine (hormone) disruption.

A U.S. Environmental Protection Agency report released in February 1997 and a December 1996 European conference sponsored by the European Commission, the European Environment Agency, the World Health Organization and the Organization for Economic Co-operation and Development found no direct link between exposure to industrial chemicals in the environment and any harmful effect on humans due to endocrine disruption.

Commercial APEs do not show estrogenic effects when evaluated in the classic laboratory animal test.

APs show no adverse estrogenic effects when given to laboratory animals.

The classic laboratory animal test shows a very weak estrogenic response from nonylphenol, the most common AP. Subsequent studies to look for potentially harmful effects, including a comprehensive, three-generation study by the U.S. government's National Institute of Environmental Health Sciences, show no impact from nonylphenol on reproduction, development or fertility of laboratory animals. Octylphenol, the second most common AP, shows no estrogenic effects in the classic laboratory animal test.

There is no effect on fish from trace levels of APs and APEs in rivers and lakes when effective sewage treatment is in place.

Environmental monitoring studies demonstrate that AP and APE concentrations in rivers and lakes in the U. S., Canada and Britain (except for one river with inadequate sewage treatment) are below amounts that may adversely affect the hormonal system in fish and other aquatic organisms.

For more information or copies of studies referenced above, please contact the APE Research Council.