Potential human reproductive and developmental effects of endocrine
active compounds (EACs) has become an area of increasingly greater concern
to industry, special interest groups, toxicologists, and regulators
These agents have been linked by some to a wide variety of adverse reproductive/developmental
health outcomes in humans. See section on "health
While ample evidence from epidemiological studies has been brought
forward in the literature which reveals that the prevalence rates
for a number of adverse reproductive/developmental outcomes are indeed
increasing, there is little credible evidence linking these changes
with exposure to man-made chemicals in general let alone EACs in particular.
See section on "Framework for
assessing weight of evidence".
There is even some question as to whether there is a true change in
prevalence for some of these outcomes such as infertility and prostate
cancer. The reported changes maybe no more than an artifact of statistical
reporting, improved diagnostic procedures, changes in medical management
and heightened awareness by the community in general and the medical
profession in particular.
In other cases meta-analyses of breast, ovarian, and endometrial cancer
have failed to find a statistical association between the adverse
outcome of concern and exposure to man-made chemicals (Adami et al.,
1995; Houghton and Ritter, 1995).
Regardless, it is important to recognize that, the absence of evidence
can not be construed as evidence of absence of an effect. The endocrine
disrupter hypothesis, while intriguing, controversial and highly emotive,
requires testing. This hypothesis, based on evidence from wildlife
studies and reports of occupational exposure and animal experiments,
is certainly plausible. However, demonstration that any of the above
mentioned adverse outcomes are indeed mediated by man-made chemicals
acting via an endocrine pathway has yet to be achieved. In addition
to man-made chemicals alternative explanations must also be identified
and investigated with equal vigor and determination as well. This
is particularly important given the potential medical, legal, economic,
social and ethical implications associated with any effects in the
general population which could be induced by EACs.
groups have advanced various definitions of endocrine disrupters.
While none has been universally accepted we propose the following
definition of endocrine disrupters and potential endocrine disrupters
developed by the International Program on Chemical Safety (IPCS; March,
An endocrine disrupter is an exogenous substance or mixture that alters
function(s) of the endocrine system and consequently causes adverse
health effects in an intact organism, or its progeny, or (sub) populations."
"A potential endocrine disrupter is an exogenous substance or
mixture that possesses properties that might be expected to lead to
endocrine disruption in an intact organism, or its progeny, or (sub)
definitions include the important point that humans are exposed to
mixtures of natural and anthropogenic chemicals. How such compounds
interact is largely unknown.