Polycarbonates pose serious health risk

Warning. What you are about to read may change the way you look at your Nalgene bottle — and any canned food or drink for that matter.

Warning. What you are about to read may change the way you look at your Nalgene bottle — and any canned food or drink for that matter.

Most common food and beverage containers are lined with plastic containing a poisonous and cancer-causing chemical known as Bisphenol-A (BPA).

And the ubiquitous chemical is leeching into our food and water supply, according to 38 of the world’s leading scientific experts on the stuff.

Average human exposure to the chemical is higher than the level that causes harm in lab animals, the expert panel concluded. Their results were published in the journal Nature last week.

Tests found BPA exposure in animals caused brain damage, hyperactivity and lower dopamine levels, which is widely considered to be the cause of Attention Deficit Disorder.

It also led to breast and prostate cancer.

Despite this, BPA is a building block for polycarbonates — the plastic used to make the popular Nalgene bottles, to line metal containers and even in modern plastic dental fillings.

“It was an act of insanity,” said Frederick vom Saal, a development biologist who participated in the study.

“It’s mad to make plastic out of a chemical known to act like a sex hormone, which has been known since the 1930s when it was considered for use as a drug.”

The chemical is held in the plastic by an incredibly unstable bond that dissolves under heat, he said during a telephone interview from his office at the University of Missouri.

“It’s not complex chemistry.”

Putting a bottle in the microwave or adding boiling water is enough to cause the chemical to leech into the water.

These are things we do all the time, especially considering that the plastic is used to make baby bottles.

Why would such dubious plastics be used?

“It makes people a lot of money,” said vom Saal.

“It looks hard, it has no odour and taste, and, because it looks like glass, there is this illusion that it’s safe, durable and stable.

“But any chemist knows that’s absolutely ludicrous.”

The list of ailments that can be attributed to BPA is staggering.

In animals it causes breast cancer, prostate cancer, ovarian disease and uterine fibroids, the major source of infertility in women.

“It’s an abortion-causing chemical,” said vom Saal.

“There are indications that the incidence of infertility is increasing and tests have shown that women who repeatedly miscarry have significantly elevated levels of BPA in their blood.”

These tests, conducted in Japan, led to the Japanese government banning the use of the plastic 10 years ago.

It is also most dangerous to children, because they are undergoing rapid development.

BPA mimics estrogen, a hormone that’s part of the body’s finely tuned messaging system.

The effects of BPA are very similar to those of Diethylstilbestrol (DES), a drug given to millions of women, which was banned in 1972 when it was found to cause cancer.

Animal testing also found that small amounts of BPA can cause animals to stop producing insulin, which could help explain the growing prevalence of Type 2 diabetes in young people.

And the list goes on.

Polycarbonate is one of the most widely used plastics in the world.

More than three billion kilograms are manufactured each year for use in plastic bottles and as the lining for all food, pop and beer cans.

The plastic prevents acids in the beer and pop from corroding the metal containers.

However, the acids still break down the tasteless, odourless BPA-laden plastic, creating a “hormone cocktail,” said vom Saal, who recently met with Canadian Health officials.

They are taking the threat very seriously, he said.

Federal scientists are in the midst of reviewing the new information on BPA, said Health Canada spokesperson Paul Duchesne.

Health Canada currently limits daily intake to 25 micrograms per kilogram of body weight.

“But this is based on results from tests done in the 1980s,” said vom Saal.

“That amount is actually 1,000 times higher than the amount we’ve found to cause adverse effects.”

It’s very clear that phenomenally small amounts of the potent chemical can cause effects, he said.

Nalgene has addressed the concerns in a written response on its website.

The company assures consumers that BPA exists only in very low residual levels, typically at parts-per-million levels.

However, experts have demonstrated that dangers exist at levels as low as parts per trillion.

“Corporations continue to produce it because they’ve invested a lot of money in polycarbonate plants and they want to see a return on that investment,” said vom Saal.

“They don’t give a damn — to hell with the public.”

There is no scientific controversy about the chemical’s dangers, said vom Saal.

However, confusion is being spread by industry-funded experiments.

“They’re doing just what the tobacco industry did,” he said.

The chemical industry funded 14 studies that have all declared that BPA causes no adverse effects.

Meanwhile, hundreds of independent studies have found just the opposite.

“When 100 per cent of the industry tests are negative and all the rest are positive, who are you going to believe?” asked vom Saal.

“Who profits from all of this?”


While the chemical is nearly impossible to avoid, vom Saal said he does everything he can to limit his intake.

Many alternative plastics exist on the market and there are always glass containers.

Look at the bottom of your Nalgene.

If it has the recycling designation number 7 it is made of polycarbonate and likely has PC stamped below.

Older containers with worn plastic are more likely to leech the chemical and you should never add hot substances or anything more acidic than water, which can also cause chemical leeching.

Ideally you should avoid using the plastic altogether.

You should avoid consuming canned foods and drinks.

And Vom Saal suggests buying a reverse osmosis water-filtration system.

Why? Because chances are that this dangerous chemical is present in our water supply.

Billions of pounds of this stuff is thrown into landfills each year, said vom Saal.

When our garbage breaks down, a chemical reaction occurs that produces heat, which in turn causes BPA to leech out into the groundwater.

“Governments know that people will panic if they tell them that it’s in their water supply,” said vom Saal.

“So they don’t. Besides, the filtration system is too slow to apply at the municipal level.”

Filtration should be done at the source to your home, as a large amount of BPA present in our blood is likely from bathing.

Your skin can absorb the chemical.

Scientists have reached a consensus on the effects of polycarbonate plastics, and the BPA that it contains.

“Now it’s up to government regulators to do something and not stick their heads in the sand, which is what they did with tobacco and, recently, with Vioxx,” said vom Saal.

“It’s deja vu all over again, and it will be deja vu when these companies are brought to litigation basically by everyone in the world.”