How we’re protected from chemical exposures.

4 03 2014

I always thought I wouldn’t have to worry about some things – like, oh,  incoming missiles,  terrorist plots, and chemicals which could destroy me – because I thought my government would have something in place to protect me.  But the recent chemical spill in West Virginia changed that: for those of you who don’t know, that was a spill of  about 10,000 gallons of what is called a “coal cleaner”  into the Elk River, contaminating the water supply of 300,000 people.

When I first began looking into the chemicals used in fabrics, and finding out that the soft, luscious fabrics we surround ourselves with every day are filled with chemicals that can cause me grievous harm, I was stopped in my tracks when someone suggested that the government wouldn’t let those chemicals in products sold in the USA – so how could fabrics contain those chemicals?   I didn’t have an answer for that, because at the time I too thought  that “of course the government must have laws in place to make sure we aren’t exposed to dangerous chemicals”!

The current regulation of chemicals in the US dates back to 1976 and the Toxic Substances Control Act (TSCA), which regulates the introduction of new or already existing chemicals.

But before talking about the TSCA, let’s first take a quick look at what’s changed since 1976,  because our understanding of the extent and pathways of chemical exposures has fundamentally changed since then.

We now know that the old belief that “the dose makes the poison” (i.e.,  the higher the dose, the greater the effect)  is simply wrong.  Studies are finding that even tiny quantities of chemicals – in the parts-per-trillion range – can have significant impacts on our health.  We’re also finding that mixtures of chemicals, each below their “no observed effect level”, may have greater environmental impacts than the chemicals alone.   In other words, toxins can make each other more toxic:   a dose of mercury that would kill 1 out of 100 rats, when combined with a dose of lead that would kill 1 out of 1000 rats – kills every rat exposed.

We also now know that timing and order of exposure is critical –  exposures can happen one after the other, or all at once.  The possible combinations of exposures is huge and knowledge is limited about the effects of mixed exposures.  During gestation and through early childhood  the body is rapidly growing  under a carefully orchestrated process that is dependent on a series of events.  When one of those events is interrupted, the next event is disrupted – and so on –  until permanent and irreversible changes result. These results could be very subtle — like an alteration in how the brain develops which impacts, for example, learning ability.  Or it could result in other impacts like modifying the development of an organ predisposing it to cancer later in life.

Add to that the concept of individual susceptibility.  For instance a large part of the population is unable to effectively excrete heavy metals, so their body burden accumulates faster, and their illnesses are more obvious.  They are the “canaries in the coal mine” in an environment that’s becoming increasingly more toxic.

We’re finding that chemicals migrate from products into the environment (and remember, we are part of the environment).

And this is where it gets really interesting:

Each of us starts life with a particular set of genes, 20,000 to 25,000 of them. Now scientists are amassing a growing body of evidence that pollutants and chemicals might be altering those genes—not by mutating or killing them, but by sending subtle signals that silence them or switch them on at the wrong times.  This can set the stage for diseases which can be passed down for generations.  This study of heritable changes in gene expression – the chemical reactions that switch parts of the genome off and on at strategic times and locations –  is called “epigenetics”.

They’re finding that exposure to chemicals is capable of altering genetic expression, not only in your children, but in your children’s children – and their children too.  Researchers at Washington State University found that when pregnant rats were exposed to permethrin, DEET or any of a number of industrial chemicals, the mother rats’ great grand-daughters had higher risk of early puberty and malfunctioning ovaries — even though those subsequent generations had not been exposed to the chemical.[1]  Another recent study has shown that men who started smoking before  puberty caused their sons to have significantly higher rates of obesity. And  obesity is just the tip of the iceberg—many researchers believe that epigenetics  holds the key to understanding cancer, Alzheimer’s, schizophrenia, autism, and  diabetes. Other studies are being published which corroborate these findings.[2]

With the advent of biomonitoring, and a growing recognition of the importance of early life exposures, low dose effects and epigenetics, the science linking environmental exposures to biological effects (i.e., disease) is becoming overwhelming.

And here’s why the Toxic Substances Control Act of 1976 is not doing the job of protecting us:

  • We assume the TSCA is testing and regulating chemicals used in industry. It is not:
    • Of the more than 60,000 chemicals  in use prior to 1976, most were “grandfathered in”; only 200 were tested for safety and only 5 were restricted.  Today over 80,000 chemicals are routinely used in industry, and the number which have been tested for safety has not materially changed since 1976.  So we cannot know the risks of exposing ourselves to certain chemicals.  The default position is that no information about a chemical = no action.
    • For those of you who don’t know, the spill in West Virginia was of “crude MCHM”, or 4-methylcyclohexanemethanol, one of the chemicals that was grandfathered in to the Toxic Substances Control Act of 1976.   That means that nobody knows for sure what that chemical can do to us.
      • Carcinogenic effects? No information available.
      • Mutagenic effects? No information available.
      • Developmental toxicity? No information available.     Lack of information is the reason the local and federal authorities were so unsure of how to advise the local population about their drinking  water supplies.  (And by the way, in January, 2014,  a federal lawsuit was filed in Charleston, WV, which claims that the manufacturer of MCHM hid “highly toxic and carcinogenic properties” of components of MCHM, hexane and methanol, both of which have been tested and found to cause diseases such as cancer.)
  • We assume that the TSCA requires manufacturers to demonstrate their chemicals are safe before they go into use.  It does not:
    • The law says the government has to prove actual harm caused by the chemical in question before any controls can be put in place.  The catch-22 is that chemical companies don’t have to develop toxicity data or submit it to the EPA for an existing product unless the agency find out that it will pose a risk to humans or the environment – which is difficult to do if there is no data in the first place.  Lack of evidence of harm is taken as evidence of no harm.
  • We assume that manufacturers must list all ingredients in a product, so if we have an allergy or reaction to certain chemicals we can check to see if the product is free of those chemicals.  It does not:
    • TSCA allows chemical manufacturers to keep ingredients in some products secret.   Nearly 20% of the 80,000 chemicals in use today are considered “trade secrets”.  This makes it impossible for consumers to find out what’s actually in a product.  And there is no time limit on the period in which a chemical can be considered a trade secret.

These limitations all help to perpetuate the chemical industry’s failure to innovate toward safer chemical and product design.  It’s one of the reasons the USA is one of the few nations in the world in which asbestos is not banned in many products.

In 2013, the Chemical Safety Improvement Act (CSIA) was introduced, however it does not deliver the critical fixes needed to fix the TSCA, although it is an improvement to the TSCA.  The Natural Resources Defense Council suggests some steps that we must take to reform the TSCA, and these apply to the CSIA also:

  • Require new and existing chemicals be assessed for safety – with mandatory and enforceable deadlines.  “Innocent until proven guilty” should not apply to chemicals.
  • Establish safety standards, especially with regard to children and other vulnerable groups.
  • Give the EPA the authority to protect the public from unsafe chemicals, including expedited action for those deemed the most toxic.
  • “Grandfathering in” spells trouble for the future.
  • Ensure the public’s right to know about the safety and use of chemicals.
  • Allow states to maintain laws which exceed federal protections to safeguard their citizens.
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I know the polyester fabric costs less, but what else comes with it?

19 06 2013

When plastic was introduced in 1869, it was advertised as being able to replace natural products like ivory and tortoiseshell in items such as jewelry, combs and buttons – so it would “no longer be necessary to ransack the earth in pursuit of substances which are constantly growing scarcer.”(1)

What a success: Plastics are versatile – they can be hard or soft, flexible or brittle, and are durable, lightweight, formable – in fact, they’re so versatile that they’ve become a vital manufacturing ingredient for nearly every existing industry. They are practically ubiquitous. And now we’re beginning to find that our relationship with plastic is not healthy. Using dwindling fossil fuels to manufacture the stuff, plastic leaches toxic chemicals into our groundwater, litters landscapes and destroys marine life. As Susan Freinkel points out in her book, Plastic: A Toxic Love Story, it’s worth noting that discoveries of plastic’s toxic effects are being made in a world that is at least ten times more plastic than it was half a century ago. In the ’60s, an American might have used about 30 pounds of plastic a year – in 2011, 300 pounds. And we’re producing 300 million tons more every year.(2)

Plastics were marketed as “the material of the future”. And how true that is, because large polymers take practically forever to break down, so much of the plastic that has ever been manufactured is still with us, in landfills, in the plastic filled gyres found in our oceans (where the mass of plastic exceeds that of plankton sixfold) (3), and the stomachs of northern seabirds. And it will stay there for hundreds if not thousands of years.

Just as some chemicals can impact children’s bodies much more than adult bodies, Judith Shulevitz, writing in the New Republic, reminds us: “plastic totally dominates the world of the child. Children drink formula in baby bottles and water in sippy cups, eat food with plastic spoons on bright melamine trays, chew on bath books and rubber ducks, and, if they don’t do these things at your house, they’ll do them at someone else’s or at school, no matter how many notes you write or mad-housewife-ish you’re willing to appear.” (4)

There are many studies to support the belief that these plastics are changing us – but what has really changed is that the scientific understanding of how these chemicals are poisoning us has undergone a conceptual revolution – our grandchildren may see our current attitudes about living with these chemicals as being analogous to doctors in the 1950s who appeared in ads for cigarettes.

Old toxicological notions are being stood on their heads. Certainly, the old “dose makes the poison” notion, which was first expressed by Paracelsus in the 16th century and which means that a substance can only be toxic if it is present in a high enough concentration in the body – because all things are poisonous in the right amounts. He wrote: “All substances are poisons; there is none which is not a poison. The right dose differentiates a poison from a remedy”. But today scientists are finding that timing of exposure might be the critical factor – a fetus might respond to a chemical at one-hundredfold less concentration or more than in an adult, and when the chemical is taken away the body is altered for life. Another theory is known as the “developmental origins of health and disease,” or DOHaD (for more about DOHaD, click here), and it paints a picture of almost unimaginably impressionable bodies, responsive to biologically active chemicals until the third generation.(5)

New methods have been developed which have taken the guesswork out of what were once theories: for example, biomonitoring now means that scientists can actually discover the degree to which people have been exposed to poisonous stuff when in the past their conclusions were largely guesswork; and microarray profiling, which means we’re beginning to understand how tiny doses of certain chemicals switch genes on or off in harmful ways during exquisitely sensitive periods of development.

Exposure to all that plastic has a cumulative effect. Now toxicologists can see that lots of tiny doses from many different estrogen-mimicking chemicals entering the body by multiple pathways can have a big impact. “If you’re being exposed to two-hundred fifty chemicals and only thirty of them have estrogenic activity, but they’re each very low, still, thirty of them might add up to be significant,” says Jerrold Heindel, of the National Institute of Environmental Health Sciences (NIEHS).

Judith Shulavith asks– if we live in this plastic environment – why we’re not sicker than we are? And sicker than we used to be? “The answer is, we’re healthier in some ways and sicker in others. Medical advances mean we’re likelier than ever to survive our illnesses, but all kinds of diseases are on the rise. Childhood cancers are up 20 percent since 1975. Rates of kidney, thyroid, liver, and testicular cancers in adults have been steadily increasing. A woman’s risk of getting breast cancer has gone from one in ten in 1973 to one in eight today. Asthma rates doubled between 1980 and 1995, and have stayed level since. Autism-spectrum disorders have arguably increased tenfold over the past 15 years. According to one large study of men in Boston, testosterone levels are down to a degree that can’t be accounted for by factors such as age, smoking, and obesity. Obesity, of course, has been elevated to the status of an epidemic.”(6)

There are many ways to explain upticks in rates of any particular ailment; for starters, a better-informed populace and better tools for detecting disease mean more diagnoses. Other environmental stressors include Americans’ weirdly terrible eating habits, our sedentary lifestyle, and stress itself. But why can’t we just figure this out and come to some conclusions about certain chemicals as the cause of certain diseases? John Vandenberg, a biologist, explains the difficulty : “Well, one of the problems is that we would have to take half of the kids in the kindergarten and give them BPA and the other half not. Or expose half of the pregnant women to BPA in the doctor’s office and the other half not. And then we have to wait thirty to fifty years to see what effects this has on their development, and whether they get more prostate cancer or breast cancer. You have to wait at least until puberty to see if there is an effect on sexual maturation. Ethically, you are not going to go and feed people something if you think it harmful, and, second, you have this incredible time span to deal with.”(7)

Which diseases, exactly, have fetal origins and which chemicals have the power to sidetrack development, and how, is the goal of a giant, 21-year study of 100,000 children called the National Children’s Study (NCS), under the auspices of the National Institutes of Health. However, in 2013, it was announced that the decade-old effort would undergo radical restructuring to cut costs.(8)

Meanwhile, what can you do to protect yourself and your family, since the government isn’t doing that job?  I’ll have some ideas next week.

(1) Freinkel, Susan, “Plastic: Too Good to Throw Away”, The New York Times, March 17, 2011
(2) Ibid.
(3) Moore, C.J., et al, “Density of Plastic Particles found in zooplankton trawls from coastal waters of Northern California to the North Pacific Central Gyre”, Algalita Marine Research Foundation
(4) Shulevitz, Judith, “The Toxicity Panic”, The New Republic, April 7, 2011
(5) Ibid.
(6) Ibid.
(7) Groopman, Jerome, “The Plastic Panic”, The New Yorker, May 31, 2010.
(8) Belli, Brita, “Changes to Children’s Study Threaten its value, experts say”, Simons Foundation Autism Research Initiative; 7 March 2013