Public Health IssueBisphenol A in Plastics

IntroductionRecent hype about a

compound found in plastic containers has perplexed retailers and consumers.

That compound is bisphenol A(BPA).

It is found in plastics types 3 and 7.

Plastics type 1, 2, 4, 5, and 6 are BPA free.

Bisphenol A’s chemical structure

Plastic Types that are made using Bisphenol A

What is Bisphenol A?Bisphenol A is a chemical

compound found in some hard, clear, lightweight plastics and resins.

It's used in the production of various types of food and drink containers, compact discs, electronics and automobile parts, and as a liner in some metal cans.

Why is it this newsworthy?Suspected of being

hazardous to humans since the 1930s, concerns about the use of bisphenol A in consumer products were regularly reported in the news media in 2008 after several governments issued reports questioning its safety, and some retailers have removed products made of it from their shelves.

What does current research show?BPA stays in the human

body longer than it was originally thought.

Most people have a detectable level in their urine.

Those with a higher level of BPA in their urine had 3x the chance for cardiovascular disease and 2.5x the chance for diabetes.

University of Rochester (January 2008).

What does current research show?Even earlier, Yale

researchers in January 2007 found that BPA was an “environmental estrogen” and interfered with the gene responsible for normal uterine development in female mice.

A link was also made in a companion study to the increased chance of breast, ovarian and prostate cancer from exposure to BPA.

What does current research show?On Oct. 6, 2009, the

journal Environmental Health Perspectives published a study which found that pregnant women exposed to BPA were more likely to have daughters with aggressive and hyperactive behaviours.

No significant effect was found among the boys the women gave birth to.

What does current research show?The American Council

of Chemistry just recently published a paper stating that “As the authors (U of Rochester) themselves note, they do not conclude that the presence of BPA is causing adverse health effects — they merely noted a statistical association.”

What does current research show?Theodore Widlanski, a

biochemistry professor at Indiana University, states "It doesn't mean that your bottled water is any less safe today than it was yesterday. It just means that if it isn't safe, we might be able to explain why."

General Health Problems Associated with BPA

Dose (μg/kg/day) Effects (in mice/rats unless stated)

Study Year

0.025 Permanent changes to genital tract

2005

0.025 Changes in breast tissue; increased risk from carcinogens

2005

1.00 Long term, adverse, reproductive effects

2009

2.00 Increased prostate weight (30%) 19972.00 Lower body weight, signs of early

puberty2002

2.40 Decline in testicular testosterone 20042.50 Breast cells are at greater cancer

risk2007

10.0 Prostate cells are at a greater cancer risk

2006

10.0 Decreased maternal behaviour 200230.0 Reversed sex differences in brain 200350.0 Adverse neurological effects in

primates2008

50.0 Disrupted ovarian development 2009

What was Canada’s response? (summary in brackets beside)

Health Canada's evaluation of bisphenol A, launched in Nov. 2007, included a review of human and animal studies around the world and research into how much of the chemical is leaching from consumer products. *(REVIEWED RESEARCH ON BPA)

In April 2008, Health Canada assessed that the chemical may pose some risk to infants and proposed classifying the chemical as "'toxic' to human health and the environment.“ (DEEMED IT TOXIC)

After the release of that assessment, Canadian Health Minister Tony Clement announced Canada's intent to ban the import, sale, and advertisement of polycarbonate baby bottles containing bisphenol A due to safety concerns, and investigate ways to reduce BPA contamination of baby formula packaged in metal cans. (BANNED IT IN CANADA)

What was Canada’s response?In May of 2008, Health

Canada assured consumers cans of tomato sauce and tins of apple juice are safe to eat and drink, after testing detected low levels of the chemical bisphenol A in the products.

The federal agency issued a statement saying trace amounts of the chemical were not cause for concern.

What was Canada’s response? (summary in brackets)

In December 2007, Vancouver-based Mountain Equipment Co-op became the first major Canadian retailer to pull polycarbonate containers from its store shelves. (MEC 1st TO PULL BPA BOTTLES OFF OF SHELVES)Tim Southam, a company spokesman, said consumers had

expressed concern about the chemical. He noted MEC would revisit its decision should Health Canada rule the chemical does not pose any health risks.

Lululemon Athletica Inc., also Vancouver-based, announced plans later the same month to stop selling plastic water bottles that contain bisphenol A. (LULULEMON WAS THE 2nd)The company did not pull bottles already in stores. Lululemon

said it had followed the issue for more than a year before deciding it would switch to new water bottles made of acrylic.

Both companies are Canadian

What was Canada’s response?(summary at bottom)

Around the same time, Wal-Mart announced that it was immediately ceasing sales in all its Canadian stores of food containers, water and baby bottles, sippy cups, and pacifiers containing bisphenol A, and that it would phase out baby bottles made with it in U.S. stores by early 2009.

Nalgene also announced it will stop using the chemical in its products, and Toys-R-Us said it too will cease selling baby bottles made from it.

Subsequent news reports showed many retailers removing polycarbonate drinking products from their shelves (Sears, The Bay, Home Depot, Canadian Tire…).

MORE COMPANIES FOLLOWED MEC and Lululemon’s EXAMPLE

What alternatives can I use?Use glass, stainless steel

or porcelain containers, especially for hot food or liquids.

For baby bottles, choose glass or look for hard plastic bottles without bisphenol A.

For preserved goods, opt for glass jars or canned goods that do not have liners containing BPA.

Homework1) Read the articles and do the questions from

the associated worksheet.