BISPHENOL A (BPA)
D. KOURETAS
2016
What is BPA?
• Bisphenol A (BPA) is an organic synthetic compound with the
chemical formula (CH3)2C(C6H4OH)2 belonging to the group of
diphenylmethane derivatives and bisphenols, with two hydroxyphenyl
groups.
• A colorless solid that is soluble in organic solvents, but poorly soluble
in water.
• It has been in commercial use since 1957
• Widely used to make polycarbonate plastics and epoxy resins.
PRODUCTION
• First synthesized by the Russian chemist Alexander Dianin in 1891.
Where is BPA found?
• Polycarbonate plastics have many applications including use in some food
and drink packaging such as water and baby bottles, compact discs,
impact-resistant safety equipment, and medical devices including those
used in hospital settings.
• Epoxy resins are used to coat metal products such as food cans, bottle tops,
and water supply pipes.
• BPA can also be found in certain thermal paper products, including some
cash register and ATM receipts. Some dental sealants and composites may
also contribute to BPA exposure
STATISTICS
How does BPA get into the body?
• BPA can leach into food
from the epoxy resin
lining of cans and from
consumer products
such as polycarbonate
tableware, food storage
containers, water
bottles, and baby
bottles.
• Additional traces of
BPA can leach out of
these products when
they are heated at high
temperatures.
• Recent studies also
suggest that the public
may be exposed to
BPA by handling cash
register receipts.
Did you know that…?
• A 2011 experiment at the Harvard School of Public Health indicated that BPA used in the lining of food
cans is absorbed by the food and then ingested by consumers. Of 75 participants, half ate a lunch of
canned vegetable soup for five days, followed by five days of fresh soup, while the other half did the
same experiment in reverse order. "The analysis revealed that when participants ate the canned soup,
they experienced more than a 1,000 percent increase in their urinary concentrations of BPA, compared
to when they dined on fresh soup."
• A 2009 study found that drinking from polycarbonate bottles increased urinary bisphenol A levels by
two thirds, from 1.2 μg/g creatinine to 2 μg/g.
• Skin absorption (thermal paper include receipts, event and cinema tickets, labels, and airline
tickets). A Swiss study found that 11 of 13 thermal printing papers contained 8 – 17 g/kg bisphenol A
(BPA). Upon dry finger contact with a thermal paper receipt, roughly 1 μg BPA (0.2 – 6 μg) was
transferred to the forefinger and the middle finger. For wet or greasy fingers approximately 10 times
more was transferred. Extraction of BPA from the fingers was possible up to 2 hours after exposure.
Further, it has been demonstrated that thermal receipts placed in contact with paper currency in a wallet
for 24 hours cause a dramatic increase in the concentration of BPA in paper currency, making paper
money a secondary source of exposure.
• Another study has identified BPA in all of the waste paper samples analysed (newspapers,
magazines, office paper, etc.), indicating direct results of contamination through paper recycling. Free
BPA can readily be transferred to skin, and residues on hands can be ingested. Bodily intake through
dermal absorption (99% of which comes from handling receipts) has been shown for the general
population to be 0.219 ng/kg bw/day (occupationally exposed persons absorb higher amounts at 16.3
ng/kg bw/day) whereas aggregate intake (food/beverage/environment) for adults is estimated at 0.36–
0.43 μg/kg bw/day (estimated intake for occupationally exposed adults is 0.043–100 μg/kg bw/day)
Why are people concerned about BPA?
• Human exposure to BPA is widespread. The
2003-2004, National Health and Nutrition
Examination Survey (NHANES), conducted by
the Centers for Disease Control and Prevention
(CDC), found detectable levels of BPA in 93% of
Americans six years and older.
• Another reason for concern, especially for
parents, may be because some laboratory
animal studies report subtle developmental
effects in fetuses and newborns exposed to low
doses of BPA.
• In 2012, the United States' Food and Drug
Administration (FDA) banned the use of BPA in baby
bottles;
•
The Endocrine Society said in 2015 that the
results of ongoing laboratory research gave
grounds for concern about the potential hazards
of endocrine-disrupting chemicals – including
BPA – in the environment, and that on the basis
of the precautionary principle these substances
should continue to be assessed and tightly
regulated
HEALTH EFFECTS (1)
HEALTH EFFECTS (2)
HEALTH EFFECTS (3)
ANIMAL RESEARCH (1)
Dose
(µg/kg/day)
Effects (measured in studies of mice or rats,
descriptions (in quotes) are
from Environmental Working Group
• BPA is an endocrine
Study
Year
0.025
"Permanent changes to genital tract"
2005
0.025
"Changes in breast tissue that predispose cells to
hormones and carcinogens"
2005
1
long-term adverse reproductive and carcinogenic
effects
2009
2
"increased prostate weight 30%"
1997
2
"lower bodyweight, increase of anogenital
distance in both genders, signs of early puberty
and longer estrus."
2002
2.4
"Decline in testicular testosterone"
2004
2.5
"Breast cells predisposed to cancer"
2007
10
"Prostate cells more sensitive to hormones and
cancer"
2006
10
"Decreased maternal behaviors"
2002
30
"Reversed the normal sex differences in brain
structure and behavior"
2003
50
Adverse neurological effects occur in non-human
primates
2008
50
Disrupts ovarian development
2009
disruptor that can
mimic estrogen and has been
shown to cause negative health
effects in animal studies.
• BPA closely mimics the structure
and function of the
hormone estradiol by binding to
and activating the same estrogen
receptor as the natural hormone.
• Early developmental stages
appear to be the period of
greatest sensitivity to its
effects and some studies have
linked prenatal exposure to later
physical and neurological
difficulties.
ANIMAL RESEARCH (2)
Environmental risk
In 2010, the U.S. Environmental Protection Agency reported that over one million pounds
of BPA are released into the environment annually. BPA can enter the environment either
directly from chemical, plastics, coat and staining manufacturers, from paper or material
recycling companies, foundries who use BPA in casting sand, or indirectly leaching from
plastic, paper and metal waste in landfills or ocean-borne plastic trash. Despite a soil halflife of only 1–10 days, BPA's ubiquity makes it an important pollutant; It was shown to
interfere with nitrogen fixation at the roots of leguminous plants associated with
the bacterial symbiont Sinorhizobium meliloti.
A 2005 study conducted in the US had found that
91–98% of BPA may be removed from water during
treatment at municipal water treatment
plants. Nevertheless, a 2009 meta-analysis of BPA
in the surface water system showed BPA present in
surface water and sediment in the US and Europe.
According to Environment Canada in 2011,
"BPA can currently be found in municipal
wastewater. Initial assessment shows that at
low levels, bisphenol A can harm fish and
organisms over time.
BPA affects growth, reproduction, and development in
aquatic organisms. Among freshwater organisms, fish
appear to be the most sensitive species. Evidence of
endocrine-related effects in fish, aquatic invertebrates,
amphibians, and reptiles has been reported at
environmentally relevant exposure levels lower than
those required for acute toxicity. There is a widespread
variation in reported values for endocrine-related effects,
but many fall in the range of 1μg/L to 1 mg/L.
A 2009 review of the biological impacts
of plasticizers on wildlife published by the Royal
Society with a focus on aquatic and
terrestrial annelids, molluscs, crustaceans, insects,
fish and amphibians concluded that BPA affects
reproduction in all studied animal groups, impairs
development in crustaceans and amphibians and
induces genetic aberrations.
Positions of national and international bodies
In November 2009, the WHO announced to organize an expert consultation in 2010 to
assess low-dose BPA exposure health effects, focusing on the nervous and behavioral
system and exposure to young children. The 2010 WHO expert panel recommended no new
regulations limiting or banning the use of BPA, stating that "initiation of public health
measures would be premature.
United States: In 2013, the FDA posted on its web site: "Is BPA safe? Yes. Based on FDA's ongoing safety
review of scientific evidence, the available information continues to support the safety of BPA for the approved
uses in food containers and packaging. People are exposed to low levels of BPA because, like many
packaging components, very small amounts of BPA may migrate from the food packaging into foods or
beverages."FDA issued a statement on the basis of three previous reviews by a group of assembled Agency
experts in 2014 in its "Final report for the review of literature and data on BPA" that said in part, "The results of
these new toxicity data and studies do not affect the dose-effect level and the existing NOAEL (5 mg/kg
bw/day; oral exposure)
In 2010, Canada's department of the environment declared BPA to be a "toxic substance" and
added it to schedule 1 of the Canadian Environmental Protection Act, 1999
In February 2016, France announced that it intends to propose BPA as an EU REACH Regulation
candidate substance of very high concern (SVHC) by 8 August 2016.
As of 10 June 2011, Turkey banned the use of BPA in baby bottles and other PC items
produced for babies.
REGULATIONS
US 2014: 12 states have banned
BPA from children's bottles and
feeding containers
In January 2010, the U.S. FDA announced that
recent studies provide reason for some concern
about the potential effects of BPA on the brain,
behavior, and prostate gland of fetuses, infants,
and children.
On 29 January 2014 EPA released
a final alternatives assessment for
BPA in thermal paper as part of its
Design for the Environment
program
Tolerable Daily Intake (TDI)
January 2015 EFSA
TDI =4 µg/kg body
weight/day
US: NOAEL
5 mg/kg bw/day oral
exposure
TDI
What can I do to prevent exposure to BPA?
• Don’t microwave polycarbonate
•
•
•
•
•
plastic food containers.
Polycarbonate is strong and durable,
but over time it may break down from
repeated use at high temperatures.
Avoid plastic containers with the #7
on the bottom (http://www.
recyclenow.org/r_plastics.html).
Don’t wash polycarbonate plastic
containers in the dishwasher with
harsh detergents.
Reduce your use of canned foods.
Eat fresh or frozen foods.
When possible, opt for glass,
porcelain, or stainless steel
containers, particularly for hot food or
liquids.
Use infant formula bottles that are
BPA free and look for toys that are
labeled BPA free.
Where can I go for more information?
For more information on what federal agencies are doing related to
BPA, visit the following web sites and search for “BPA.”
• U.S. Department of Health and Human Services:
• http://www.hhs.gov
• U.S. Food and Drug Administration:
• http://www.fda.gov
• Centers for Disease Control and Prevention:
• http://www.cdc.gov
• U.S. Environmental Protection Agency:
• http://www.epa.gov
• Consumer Product Safety Commission:
• http://www.cpsc.gov
• National Institute of Environmental Health Sciences:
• http://www.niehs.nih.gov
• National Toxicology Program:
• http://ntp.niehs.nih.gov