Toxic Plastic ■ 111about the chemicals that have replaced BPA,
some of which are also estrogen mimics.
In the last several years, scientists all over the
world have shown that BPA disrupts meiosis and
mitosis and causes a plethora of health problems
in mice and rats, including breast and prostate
cancer, miscarriage and birth defects, diabe-
tes and obesity, and even behavioral problems
such as attention deficit hyperactivity disor-
der. Whether BPA is causing similar diseases
in humans remains unknown; such hypotheses
are hard to test because most people already
have BPA in their bodies, making experimental
control groups difficult to set up. BPA has been
found in human blood, urine, breast milk, and
amniotic fluid. In 2016, Hunt and her colleagues
found “near-universal exposure” to BPA in a
group of pregnant women in the United States.
A major source of that exposure, they found,
was cash register receipts, which can be hard to
avoid touching.
Hunt, Soto, and Sonnenschein continue to
explore the effects of BPA; they are studying how
exposure to low doses of BPA affects monkeys,
a model animal that more accurately represents
the human system. “We’re slowly raising aware-
ness,” says Hunt, “and slowly changing things.”At the same time that Soto, Sonnenschein,
and Hunt were doing their work, Frederick
vom Saal at the University of Missouri found
that male mice that had been exposed to BPA
in utero—even at very low doses—had dramati-
cally enlarged prostates in adulthood that were
hypersensitive to hormones. This study suggests
that men are also at risk of health effects
from BPA.
In 2007, Hunt followed up her original work
with a study that she says made the first paper
look like “child’s play.” Her team exposed preg-
nant mice to BPA just as their female fetuses
were producing a supply of eggs in their ovaries.
When that second generation of females became
adults, their eggs were also damaged, Hunt
found, demonstrating that BPA exposure affects
not just adult females, but two generations of
their offspring.
Exposure aside, not everyone agrees that BPA
is toxic. Numerous companies that manufacture
plastics have conducted studies whose results
do not match Hunt’s and vom Saal’s results. To
reach a scientific consensus, on November 28,
2006, Soto, Sonnenschein, Hunt, vom Saal, and
34 other researchers from across the United
States gathered at the University of North Caro-
lina in Chapel Hill to summarize the research on
BPA. The result of their two-day meeting was the
“Chapel Hill Bisphenol A Consensus Statement,”
summarizing hundreds of studies done in vitro
and in vivo over the previous 10 years. Complet-
ing this analysis, the group concluded firmly that
BPA exposure at current levels in our environ-
ment presents a risk to human health (see “What
Can You Do?” on page 108). “It was quite clear
that there is a serious problem,” says Soto.
Over time, many baby-bottle manufacturers
took BPA out of their bottles, even as government
regulators were slower to respond. “As scientists,
our role is to call attention to what is wrong, but
it is the role of the politicians to act on it and try
to straighten it out,” says Sonnenschein. Then,
in July 2012, the FDA banned BPA from baby
bottles and children’s drinking cups, though the
prohibition does not apply to the use of BPA in
other types of containers (Figure 6.11). There
is still concern, however, from many scientists
Figure 6.11
BPA-free bottles and cans are now widely available
If you are concerned about being exposed to BPA, check labels before
you buy.