"Bisphenol A: A Scientific
Evaluation" Concludes That Risk of
Bisphenol A to Humans is Very Low
October 4, 2004
A recent paper (1) by
Professor Michael A. Kamrin (2)reports
the conclusions of his scientific evaluation of the
safety of bisphenol A (BPA) in a concise form that is
very readable. In his overall conclusion, Professor
"[I]t is very unlikely that humans, including
infants and young children, are at risk from the presence
of BPA in consumer products."
To reach his conclusions, Professor Kamrin systematically
evaluated the extensive scientific research on BPA from
several perspectives, each of which is summarized in
- What is it and how is it used?
- How are children and adults exposed to BPA?
- What is the magnitude of BPA exposure?
- What is the toxicity of BPA?
- What kinds of toxic effects does BPA cause?
- What are the risks of BPA in humans?
As reported by Professor Kamrin, BPA is primarily used
as a raw material to make polycarbonate plastic and
epoxy resins, both of which are used in a variety of
consumer products, including some that come into contact
with food. Realistic human exposure to BPA, primarily
through food, has been estimated to be in the range
of about 0.001 to 0.1 micrograms/kilogram body weight/day.
The available data suggest that exposures per body weight
for adults and young children are similar.
Based on extensive toxicity test data, acceptable exposure
levels in the range of 10-50 micrograms/kilogram body
weight/day have been established by government agencies
worldwide. These acceptable levels are set to be at
least 1000 times below the lowest levels at which effects
are seen in toxicity tests on laboratory animals, partly
under the assumption that humans may be more sensitive
than laboratory animals to toxic effects from BPA exposure.
A comparison of the high end of the realistic exposure
range with these acceptable exposure levels results
in an estimated margin of safety of 100-500. As pointed
out by Professor Kamrin, the actual margin of safety
is likely to be even higher since metabolism studies
have shown that humans are likely to be less sensitive
to toxic effects from BPA exposure than laboratory animals,
contrary to the assumption used to set the acceptable
Based on his scientific evaluation, Professor Kamrin's
paper concludes with the following overall assessment:
"Thus, the evidence that has been collected
in recent years coupled with experience from decades
of occupational exposures indicates that the risk
of BPA to humans of all ages is very low. It is thus
very unlikely that humans, including infants, will
suffer any adverse consequences, including endocrine-related
effects, from current exposures to BPA in food, drink,
or other consumer products."
1. "Bisphenol A: A Scientific
Evaluation." Medscape General Medicine, 6(3), 2004.
Available on the Internet at http://www.medscape.com/mgmhome
in the Special Articles section. Free registration is
required to access the article.
2. Michael A. Kamrin, PhD, Professor
Emeritus, Institute for Environmental Toxicology, Michigan
State University, East Lansing, Michigan.