Case Study 3: Endocrine Disruptors: Approaches to Uncertainty

Many of the threats to environmental health arise from chemicals, especially because in the US, there are about 80,000 different chemicals used in industrial and agricultural processes in the US, and only about 2 percent have been tested for toxicity, whereas only about one-half of one percent has been tested for carcinogenicity, in part because testing is so expensive. In recent years, the environmental health threat from chemicals has mounted, because very low doses of organic compounds (like chlorine), doses far below that found to induce cancer, are now thought to be responsible for reproductive-related disorders associated with endocrine disruption. Behaving as synthetic estrogens, these endocrine disruptors are believed to be responsible for the declining sperm count in males, a decline evident since the 1950s. As a result of many small doses of organic compounds, males of many species have become feminized and, as a result, the species have gone extinct. In other cases, the increase of estrogens has caused a variety of additional, reproductive-related cancers (Colborn et al. 1993).

The Colborn and her colleagues (1993) argue that large amounts of chemicals have been released into the environment since World War II. Many of these chemicals, Colborn argues, have disrupted the endocrine systems of animals. (The endocrine system consists of glands that regulate various bodily functions, such as growth, reproduction, and nutrition, by means of hormones). Because many human made industrial chemicals act as synthetic estrogens, they can disrupt the bodily functions that natural hormones regulate. Even minute exposures to these artificial chemicals, at any point in life, can pass them on to offspring during pregnancy and lactation. Colborn and her scientific colleagues argue that such chemicals can have adverse effects on reproductive and immune systems in humans and wildlife, even at levels far below those necessary to induce cancer. As a consequence, she argues for caution in employing these chemicals, a caution that would require much tighter environmental regulation. Some of these endocrine disrupting chemicals include PCBs, dioxin, and DDT. Colborn and those who argue that even small amounts of such endocrine-disrupting chemicals are risky thus assume that ethics requires one, in the face of incomplete scientific information, to use the precautionary principle. (The precautionary principle specifies that positive evidence of societal harm is not necessary before one takes precautions to protect public health. The rationale for the principle is that if one always waits until conclusive evidence of definite harm is available, then many public-health threats would be so advanced that it would be far more difficult to stop them and to prevent catastrophe. Proponents of the precautionary principle also argue that failure to employ the principle would amount to using humans as guinea pigs in industrial and economic experiments. Finally, proponents of the principle argue that because vested interests are so powerful, they often keep government from doing the necessary studies to confirm public-health harms arising from activities of those vested interests. They note, for example, that less than two percent of industrial and agricultural chemicals (of the 80,000 to 100,000 currently in use) have actually been tested for any health effects. In the absence of complete scientific studies about some hazard, proponents of the precautionary principle say it is necessary to take extra precautions to protect public health).

Besides supporting the precautionary principle, Colborn and other scientists (who argue that even small amounts of endocrine-disrupting chemicals likely are dangerous) claim that much scientific and public health evaluation of these chemicals has been scientifically inadequate. They say (1) endocrine disrupting effects occur at levels several orders of magnitude lower than those needed to cause cancer, and that government currently requires no tests for such effects. Yet, they note (2) that laboratory tests and field data have revealed endocrine-disrupting effects on other animals. Besides, they claim (3) that the best scientific explanation of the reason for the continuing decline in human sperm counts, since 1950, is that humans are responding in the same way, in response to these chemicals, as other animals. Factually, Colborn and her coauthors assume that seriously damaging effects of endocrine disruptors, on other species, argues for caution in exposing humans to these chemicals.

On the ethical side, Colborn and her coauthors recommend more study of potentially endocrine disrupting chemicals, as well as their precautionary regulation, for at least two additional reasons. (A) They say ethics requires one to be especially careful of low-dose chemical effects because they often are incurred during neonatal periods but not manifested till middle age; ethics requires extra precaution with effects that are delayed, and therefore hard to detect, and with effects that are most damaging to the most vulnerable individuals, namely developing children. (B) They also say that ethics requires one to be especially careful of these chemicals because their effects are permanent and irreversible.

Reference

Theo Colborn et al., "Environmental Endocrine Disruptors," Environmental Health Perspectives 101, no. 5 (October 1993), pp. 378-384.

Q)

1. Provide a background description of the ethical issue.

2. How will professionalism be required to address this concern?

3. Discuss how the legal standards of health care practice come into play.

4. Describe how interdisciplinary collaboration can be achieved through leadership and community stewardship to address this ethical issue.