Order Code RS22869
Updated September 8, 2008
Bisphenol A (BPA) in Plastics
and Possible Human Health Effects
Linda-Jo Schierow
Specialist in Environmental Policy
Resources, Science, and Industry Division
Sarah A. Lister
Specialist in Public Health and Epidemiology
Domestic Social Policy Division
Summary
Bisphenol A (BPA) is used to produce certain types of plastic. Containers made
of these plastics may expose people to small amounts of BPA in food and water. Some
animal experiments have found that fetal and infant development may be harmed by
small amounts of BPA, but scientists disagree about the value of the animal studies for
predicting harmful effects in people. At least one regulatory decision in the face of the
scientific disagreement has led to a congressional inquiry into the extent to which the
decision was based on good science. Legislation proposed in April 2008, S. 2928,
would prohibit use of BPA in some products intended for use by children. Legislation
proposed in June 2008, H.R. 6228, would prohibit the use of BPA in food and beverage
containers regulated by the Food and Drug Administration (FDA).
Introduction. Bisphenol A (BPA)1 is a synthetic chemical compound produced in
the United States in large quantities, approximately 2.3 billion pounds annually.2 The
dominant use is in manufacturing certain forms of plastic: relatively hard, clear
polycarbonate (PC), and epoxy resins that are used to line food cans. Under certain
conditions, BPA may migrate (i.e., be released) from PC containers and plastic-lined cans
into the food or liquids they contain.
1 Bisphenol A also is commonly known as carboxylic acid. It is the single molecule that is
chained together (polymerized) to form polycarbonate.
2 U.S. Department of Health and Human Services (HHS), National Toxicology Program, “Draft
NTP Brief on Bisphenol A,” April 14, 2008, at [http://cerhr.niehs.nih.gov/chemicals/bisphenol/
BPADraftBriefVF_04_14_08.pdf].

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The widespread use of BPA and the potential for human exposure, together with
accumulating scientific evidence about possible BPA toxicity, led the National
Toxicology Program (NTP) at the National Institutes of Health (NIH) to select BPA for
a comprehensive review. NTP released a draft “brief” on BPA on April 14, 2008.3 Its
conclusions prompted some to call for federal restrictions on certain BPA uses, and
sparked congressional and media interest in the past and current positions of the Food and
Drug Administration (FDA). FDA regulates BPA and other chemicals used in food
containers and maintains that current uses of BPA are safe. A final NTP monograph on
BPA was released September 3, 2008.4
Health Effects. Exposure to large amounts of BPA is acutely toxic to humans and
animals, but levels of BPA exposure from plastics are low. The possibility of human
health effects from exposure to low doses of BPA is controversial, although animal
evidence of possible harmful effects has been mounting for about 10 years. It is clear that
BPA is capable of interfering with the action of estrogen, an important regulator of
reproduction and development. (Interference with hormonal action is often referred to as
endocrine disruption.) Therefore, many recent studies have focused on the potential
effects of low levels of BPA exposure on fetal or newborn rats or mice. Some of the
developmental effects seen among rodents exposed to low doses of BPA include changes
in brains and behaviors; precancerous lesions in the prostate and mammary glands; altered
prostate and urinary tract development; and early onset of puberty.5
These low-dose experiments are difficult to conduct, in part because BPA is
ubiquitous in the environment. Thus, different studies have produced different results.
Scientists employed by BPA manufacturers and some independent contractors argue that
the hundreds of studies conducted so far have produced inconsistent results and are
insufficient justification for more stringent BPA regulation. Other scientists maintain that
well-designed and executed studies of sufficient statistical power on sensitive strains of
laboratory rodents have clearly demonstrated the toxicity of low doses of BPA in
mammals, and justify actions to reduce exposure for potentially vulnerable human
populations.
Some researchers have proposed that BPA may interfere with hormones that regulate
functions other than reproduction. A recently released study found that low-level
exposure to BPA inhibits the release of adiponectin from human adipose (fat) tissue.
Adiponectin increases insulin sensitivity and helps regulate glucose metabolism.6 The
researchers hypothesize that environmental BPA exposure may increase susceptibility to
3 Ibid.
4 U.S. Department of Health and Human Services (HHS), National Toxicology Program, Center
for the Evaluation of Risks to Human Reproduction, “NTP-CERHR Monograph on the Potential
Human Reproductive and Developmental Effects of Bisphenol A,” NIH Publication No. 08-5994,
September 2008, 321pp, at [http://cerhr.niehs.nih.gov/chemicals/bisphenol/bisphenol.pdf].
5 NTP Monograph on Bisphenol A, p. 7-8.
6 Hugo, Eric R., Brandebourg, Terry D., Woo, Jessica G., et al., “Bisphenol A at Environmentally
Relevant Doses Inhibits Adiponectin Release from Human Adipose Tissue Explants and
Adipocytes,” Environmental Health Perspectives, online August 14, 2008, at
[http://www.ehponline.org/members/2008/11537/11537.pdf].

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obesity and diabetes. The body of research in this area is less extensive than that into
BPA’s potential effects on reproductive hormones.
Human Exposure. Bisphenol A exposure in the general population comes
primarily from consumption of food and beverages.7 The latest national survey by the
Centers for Disease Control and Prevention (CDC) found BPA in the urine of more than
92% of the people studied, which included children six years of age and older and adults.8
Among these people, the highest average concentrations were found in children.9 The
NTP monograph estimates that the highest daily intakes of BPA occur in infants and
children.10 BPA has been found in human breast milk, but the NTP report estimates that
infants who are formula-fed have higher daily BPA intake levels than those who are
breast-fed,11 because there is more BPA in infant formula than in breast milk, and because
BPA may increase when PC baby bottles are used for formula feeding, especially if the
bottles are heated. These BPA exposure levels in humans “are similar to levels of [BPA]
associated with several ‘low’ dose laboratory animal findings of effects on the brain and
behavior, prostate and mammary gland development, and early onset of puberty in
females,” according to the final NTP monograph.12
Current Federal BPA Regulation. Depending on its use, BPA is potentially
regulated by various regulatory agencies, including the Consumer Product Safety
Commission, the Environmental Protection Agency, and the Occupational Safety and
Health Administration. BPA-containing PC polymers and epoxy resins used in food
containers — such as baby bottles and infant formula cans, respectively — are regulated
by FDA as food contact substances.13 FDA conducts research into the possible endocrine
disrupting effects of BPA. Agency regulations and guidance for industry include
recommendations and guidelines for studies of potential reproductive, developmental, and
neurological toxicity that may result from exposure to food contact substances.14 These
sources do not suggest that there is a systematic review process to study such effects that
may result from exposure to previously approved products. Some consumer groups have
7 NTP Monograph on Bisphenol A, p. 1.
8 Calafat, Antonia M., Xiaoyn Ye, Lee-Yang Wong, et al., 2008, “Exposure of the U.S.
Population to Bisphenol A and 4-tertiary-Octylphenol: 2003-2004,” Environmental Health
Perspectives, v. 116, n. 1, p. 39-44.
9 Ibid.
10 Certain occupational groups are estimated to have the highest human exposure levels. NTP
Monograph on Bisphenol A, p. 2.
11 Ibid., p. 3.
12 Ibid., p. 7-8.
13 Applicable FDA regulations are at 21 CFR §§ 177.1580, 175.300(b)(3)(viii), 177.1440, and
177.2280. See also FDA’s Food Contact Substance Notification Program, at
[http://www.cfsan.fda.gov/~dms/fcnrpt.html], and FDA’s Consumer Update, “Safety and Food
Packaging” at [http://www.fda.gov/consumer/updates/foodpackaging081908.html].
14 See, in particular, FDA, “Toxicological Principles for the Safety Assessment of Food
Ingredients,” (the “Redbook”), updated July 2007, at [http://www.cfsan.fda.gov/~redbook/red-
toca.html].

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sought for more than 10 years to have FDA declare uses of BPA-containing food contact
substances unsafe, especially in packaging for infant formula.
Events Surrounding the Current Controversy. In early 2007, NTP convened
an expert panel to conduct a comprehensive review of the scientific literature on BPA.
The panel met during 2007 and issued its report on November 26, 2007.15 It concluded
that animal studies were sufficient to elicit “some concern” about possible effects of BPA
exposure on the neurological development of human fetuses and newborns, but “minimal
concern” about effects on the early onset of puberty or development of mammary or
prostate cancer. (The expression of “some concern” is midway in a qualitative scale used
by NTP. In order, from greatest to least, the levels of concern are serious concern,
concern, some concern, minimal concern, and negligible concern.) Some scientists
disagreed with these conclusions.
NTP’s own scientists reviewed the panel report, as well as numerous studies that
were not considered by the panel, many that were completed or published in late 2007 and
early 2008. NTP then issued its draft BPA “brief” on April 14, 2008, which largely
agreed with the panel report, but expressed a higher level of concern with respect to early
puberty and effects on the mammary and prostate glands. The draft report concluded, “...
the possibility that [BPA] may alter human development cannot be dismissed.”16
Specifically, the NTP report concluded that there is “some concern” for neural and
behavioral effects in fetuses, infants, and children at current levels of human exposure,
and “some concern” in those same groups for effects on the prostate gland, mammary
gland, and on earlier age of puberty in females. Public comment on the draft brief was
invited through May 23, 2008.17
On June 11, 2008, the NTP Board of Scientific Counselors met to review the draft
report and public comments. The Board voted to lower the level of concern for BPA’s
effects on the mammary gland and on the onset of puberty in females.18 This vote is
reflected in the final version of the NTP brief, which was included in the NTP monograph
and issued September 3, 2008.19 Thus, the official NTP view is that current levels of
human exposure to BPA warrant “some concern” for possible effects on the brain,
behavior, and prostate gland in fetuses, infants, and children; “minimal concern” for
effects on the mammary gland and an earlier age for puberty in female fetuses, infants,
and children, and for workers exposed occupationally; and “negligible concern” for all
other current exposures and reproductive or developmental effects.
15 HHS, National Toxicology Program, “Expert Panel Report on the Reproductive and
Developmental Toxicity of Bisphenol A,” at [http://cerhr.niehs.nih.gov/chemicals/bisphenol/
BPAFinalEPVF112607.pdf].
16 Draft NTP Brief on Bisphenol A, p. 9.
17 National Institute of Environmental Health Sciences, “Since You Asked - Bisphenol A,” at
[http://www.niehs.nih.gov/news/media/questions/sya-bpa.cfm].
18 National Institute of Environmental Health Sciences, “Actions on the Draft NTP Brief on
Bisphenol A by the NTP Board of Scientific Counselors (BSC), June 11, 2008,” at
[http://ntp.niehs.nih.gov/files/BSCactionsBPA_508.pdf].
19 NTP Monograph on Bisphenol A, p. vii.

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Canada published its risk assessment of BPA in April 2008, finding that “... the main
source of exposure [to BPA] for newborns and infants is through the use of polycarbonate
baby bottles when they are exposed to high temperatures and the migration of [BPA] from
cans into infant formula. The scientists concluded in this assessment that bisphenol A
exposure to newborns and infants is below levels that may pose a risk, however, the gap
between exposure and effect is not large enough.”20 The Canadian government has said
that although exposure levels are below those that could cause health effects, they are
close to those levels, and the government wants to be prudent and reduce exposures
further. It announced its intention to reduce BPA exposure in infants and newborns by (1)
banning PC baby bottles, (2) developing stringent migration targets for BPA in infant
formula cans, and (3) working with industry to develop alternative food packaging and
a code of practice.
Also in April 2008, the American Chemistry Council, which represents chemical
manufacturing companies, called on FDA to update its review of the safety of BPA in
food contact applications, saying, “The extensive body of scientific study regarding [BPA]
is well documented and well reviewed. Nevertheless, recent media reports have raised
concerns about the safety and use of polycarbonate plastic and epoxy resins, unnecessarily
confusing and frightening the public.”21
Shortly thereafter, FDA formed an agency-wide task force to review current
information regarding BPA in all FDA-regulated products. In June 2008, FDA asked its
Science Board, the advisory board to the FDA Commissioner, to establish a subcommittee
to review research on BPA and exposures from food containers, and deliver its findings
to the Board’s annual meeting in the fall.22 Subsequently, Rosa DeLauro, Chairwoman
of the House Appropriations Subcommittee on Agriculture (which funds FDA), wrote to
FDA urging that the Science Board review BPA exposures from medical devices as
well.23 In August 2008, FDA published a draft risk assessment of BPA in food contact
applications, saying, “FDA has concluded that an adequate margin of safety exists for
BPA at current levels of exposure from food contact uses. At a later date, FDA will
publish a separate document that provides a safety assessment of BPA exposure from
other FDA-regulated products.”24 The BPA Subcommittee of the FDA Science Board is
20 Health Canada, “Government of Canada Takes Action on Another Chemical of Concern:
Bisphenol A,” press release, April 18, 2008, at [http://www.hc-sc.gc.ca/ahc-asc/media/nr-cp/
2008/2008_59_e.html].
21 American Chemistry Council, “ACC Calls on FDA to Update Review of Bisphenol A,” press
release, April 17, 2008, at [http://www.americanchemistry.com/s_acc/index.asp].
22 FDA, “FDA’s Chief Scientist Asks Science Board Subcommittee to Review Research on
Bisphenol-A,” press release, June 6, 2008, at [http://www.fda.gov/opacom/hpnews.html].
23 Congresswoman Rosa L. DeLauro, “DeLauro Presses for Expanded FDA Inquiry of BPA
Health Risks,” press release, June 16, 2008, at [http://www.house.gov/delauro/news.html].
24 FDA, “Draft Assessment of Bisphenol A for Use in Food Contact Applications,” August 14,
2008, p. 2, at [http://www.fda.gov/ohrms/dockets/ac/08/briefing/2008-0038b1_01_00_
index.htm]. FDA’s definition of safety in this context is that “there is a reasonable certainty in
the minds of competent scientists that the substance is not harmful under the intended conditions
of use.” 21 CFR § 170.3(i).

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due to meet on September 16, 2008, to review the draft risk assessment, the NTP Brief,
and other information regarding the safety of current food-contact uses of BPA.
Various states have enacted, or are considering, legislation to restrict use of BPA in
products intended for use by infants and children. Also, concerns about the effects of
BPA are affecting decisions in the marketplace, such as those by Wal-Mart, Playtex Infant
Care, and Nalgene to stop allowing BPA in the bottles they produce or sell.25
Congressional Activity. On January 17, 2008, John D. Dingell, chairman of the
House Committee on Energy and Commerce, and Bart Stupak, chairman of the
Subcommittee on Oversight and Investigations, announced an investigation into the use
of BPA in products intended for use by infants and children, and FDA’s determination of
the safety of current uses of BPA in FDA-regulated products.26
On April 29, 2008, legislation (S. 2928) was introduced that would prohibit the use
of BPA in some products intended for use by a child seven years old or younger. On June
10, 2008, legislation (H.R. 6228) was introduced that would amend FDA’s authority such
that food or beverage containers composed of BPA, or that could leach BPA into food or
beverages, would be considered adulterated and could not be marketed. The latter bill
was introduced during a hearing of the House Energy and Commerce Subcommittee on
Commerce, Trade, and Consumer Protection on the safety of BPA and phthalates.27
Conclusion. There is scientific consensus that exposure to high levels of BPA can
cause adverse reproductive effects in mammals. It is less clear that low-dose exposures
are harmful. There is, however, growing concern about low-dose exposures among the
public, and among many scientists, sharpened by the fact that BPA exposures within the
general population are, without question, highest in infants. The scientific debate about
the safety of BPA is likely to continue, and further reaction in the policy, regulatory, and
commercial arenas is expected.
25 See, for example, Connecticut legislation at [http://www.cga.ct.gov/2008/FC/2008HB-05601-
R000670-FC.htm], and “Companies Move to Curb Risk From Chemical BPA,” Associated Press,
April 21, 2008.
26 Correspondence related to the investigation is at U.S. Congress, House of Representatives,
Committee on Energy and Commerce website, at [http://energycommerce.house.gov/
Investigations/Bisphenol.shtml].
27 House Energy and Commerce Committee, Subcommittee on Commerce, Trade, and Consumer
Protection, hearing on “Safety of Phthalates and Bisphenol-A in Everyday Consumer Products,”
June 10, 2008, 110th Cong., 2nd Sess., Washington, D.C. Phthalates are a class of chemicals that
are used to soften plastics, and that are found in a variety of consumer products. For more
information, see CRS Report RL34572, Phthalates in Plastics and Possible Human Health
Effects, by Linda-Jo Schierow and Margaret Mikyung Lee.

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