Modern life and its 80,000 chemicals

There is an estimated 80 thousand chemicals used in modern life today, and the following three articles expound on how some of them supposedly affect us.  These articles were originally published by The New York Times, American Council on Science and Health, and The Huffington Post, respectively.

The first article tells us how chemicals adversely affect us, the second is a rebuttal, and the third is about a marine biologist named Rachel Carson, who, from about 50 years ago, began publishing a series of articles in The New Yorker, sounding the alarm about the dangers of exposure to chemicals and the failure of the chemical industry and government regulators to protect people from those dangers.

How Chemicals Affect Us

By Nicholas D. Kristof – NY Times

A widely used herbicide acts as a female hormone and feminizes male animals in the wild. Thus male frogs can have female organs, and some male fish actually produce eggs. In a Florida lake contaminated by these chemicals, male alligators have tiny penises.

These days there is also growing evidence linking this class of chemicals to problems in humans. These include breast cancer, infertility, low sperm counts, genital deformities, early menstruation and even diabetes and obesity.

Philip Landrigan, a professor of pediatrics at Mount Sinai School of Medicine, says that a congenital defect called hypospadias — a misplacement of the urethra — is now twice as common among newborn boys as it used to be. He suspects endocrine disruptors, so called because they can wreak havoc with the endocrine system that governs hormones.

Endocrine disruptors are everywhere. They’re in thermal receipts that come out of gas pumps and A.T.M.’s. They’re in canned foods, cosmetics, plastics and food packaging. Test your blood or urine, and you’ll surely find them there, as well as in human breast milk and in cord blood of newborn babies.

In this campaign year, we are bound to hear endless complaints about excessive government regulation. But here’s an area where scientists are increasingly critical of our government for its failure to tackle Big Chem and regulate endocrine disruptors adequately.

Last month, the Endocrine Society, the leading association of hormone experts, scolded the Food and Drug Administration for its failure to ban bisphenol-A, a common endocrine disruptor known as BPA, from food packaging. Last year, eight medical organizations representing genetics, gynecology, urology and other fields made a joint call in Science magazine for tighter regulation of endocrine disruptors.

Shouldn’t our government be as vigilant about threats in our grocery stores as in the mountains of Afghanistan?

Researchers warn that endocrine disruptors can trigger hormonal changes in the body that may not show up for decades. One called DES, a synthetic form of estrogen, was once routinely given to pregnant women to prevent miscarriage or morning sickness, and it did little harm to the women themselves. But it turned out to cause vaginal cancer and breast cancer decades later in their daughters, so it is now banned.

Scientists have long known the tiniest variations in hormone levels influence fetal development. For example, a female twin is very slightly masculinized if the other twin is a male, because she is exposed to some of his hormones. Studies have found that these female twins, on average, end up slightly more aggressive and sensation-seeking as adults but have lower rates of eating disorders.

Now experts worry that endocrine disruptors have similar effects, acting as hormones and swamping the delicate balance for fetuses in particular. The latest initiative by scholars is a landmark 78-page analysis to be published next month in Endocrine Reviews, the leading publication in the field.

“Fundamental changes in chemical testing and safety determination are needed to protect human health,” the analysis declares. Linda S. Birnbaum, the nation’s chief environmental scientist and toxicologist, endorsed the findings.

The article was written by a 12-member panel that spent three years reviewing the evidence. It concluded that the nation’s safety system for endocrine disruptors is broken.

“For several well-studied endocrine disruptors, I think it is fair to say that we have enough data to conclude that these chemicals are not safe for human populations,” said Laura Vandenberg, a Tufts University developmental biologist who was the lead writer for the panel.

Worrying new research on the long-term effects of these chemicals is constantly being published. One study found that pregnant women who have higher levels of a common endocrine disruptor, PFOA, are three times as likely to have daughters who grow up to be overweight. Yet PFOA is unavoidable. It is in everything from microwave popcorn bags to carpet-cleaning solutions.

Big Chem says all this is sensationalist science. So far, it has blocked strict regulation in the United States, even as Europe and Canada have adopted tighter controls on endocrine disruptors.

Yes, there are uncertainties. But the scientists who know endocrine disruptors best overwhelmingly are already taking steps to protect their families. John Peterson Myers , chief scientist at Environmental Health Sciences and a co-author of the new analysis, said that his family had stopped buying canned food.

“We don’t microwave in plastic,” he added. “We don’t use pesticides in our house. I refuse receipts whenever I can. My default request at the A.T.M., known to my bank, is ‘no receipt.’ I never ask for a receipt from a gas station.”

I’m taking my cue from the experts, and I wish the Obama administration would as well.

Rebuttal:

Why I Don't Write About Pottery from the Ming Dynasty (Medical Progress Today) 

By Jonathan (Josh) Bloom, Ph.D. 

Sometimes it's good to recognize your limitations.

For example, I could describe how DNA works, or how to make crystal meth, poison your neighbor or blow stuff up. I won't, but I could. And I'd know what I was talking about.

Perhaps I could also write something about teapots from the Ming Dynasty if I read about it on Wikipedia, but in reality I wouldn't know one if it fell off the Chrysler Building onto my head.

Nicholas Kristof is a columnist for The New York Times. As such, he has written about a wide range of topics such as politics, human rights, poverty, foreign affairs, and economics. He does this extremely well, as demonstrated by his multiple awards, including two Pulitzer Prizes. He also appears to be nothing short of brilliant, and an all-around good guy as well.

But sometime prior to May 2nd, when his last column, "How Chemicals Affect Us" was published, he may have been walking a little too close to the Chrysler Building.

Kristof's formal training is in law and foreign languages. Notably absent are: chemistry, toxicology, pharmacology and reproductive biology. Which is a shame, because that is what his entire piece was about.

And it showed. Kristof rattled off a bunch of mostly unrelated claims, that, to a non-scientist would appear very scary. These involved the usual suspects, such as increasing cancer rates, low sperm counts and a host of others. But once you scratch beneath the surface, a very different story arises.

The column makes generous use of the nonsensical term "endocrine disruptor," something that is supposed to interfere with our endocrine system--the incredibly complex series of glands that produce hormones. "Disruptor" is a nice scary sounding word, but scientifically meaningless. What exactly do endocrine disrupters disrupt? And how?

In your body, hormones, whether synthetic or natural, interact with receptors on particular cells and elicit a response. Two common natural hormones are estrogen and testosterone, both critical to sexual development. Drugs frequently interact with hormone receptors and either amplify or diminish a physiological process. The breast cancer drug Tamoxifen blocks the estrogen receptors in breast tissue, suppressing the growth of cancer cells that are dependent on estrogen to replicate.

Once in a while something will go very wrong.

A particularly awful example of this was diethylstilbesterol (DES), a drug that until 1971 was sometimes given to pregnant women since it was thought to prevent miscarriages and premature deliveries. But its use was discontinued after it was discovered that it caused a rare cancer and reproductive abnormalities in the daughters of mothers that took the drug. Sons had different and less serious conditions, but by any measure, this was a drug disaster.

Thalidomide, used for morning sickness more than 50 years ago was found to be a potent teratogen-- a chemical that can cause severe developmental problems. Children of mothers that took this drug often were born with undeveloped arms or legs, or sometimes none at all.

Even today, teratogenic drugs exist, but they are treated quite differently. Accutane, used for severe acne, is a powerful teratogen. However Roche, its maker, is so careful that it doesn't get near a pregnant woman that a pregnancy test is required every month before it can be purchased and the women needs to sign a form swearing she's using at least two methods of birth control.

It is very rare, but still possible for these unforeseen side effects to occur; however, modern preclinical assays make this much less likely for drugs.

But can you take a serious teratogen like DES or thalidomide, which were given in therapeutic quantities to pregnant women, and claim any relevance to trace chemicals found in everyday life?

At this point it becomes clear that Kristof is entering the Ming Dynasty. He equates DES with a chemical called bisphenol-A (BPA), a component of many plastics that has been in use for more than 50 years. Very small amounts of BPA leach out from the plastic, which has caused it to be tested a bazillion times, with no evidence of human harm. Sometimes, if you shovel enough into a rat, bad things can happen, but you better have a big shovel. Even the FDA has said, on several occasion and despite withering activist pressure, that it is safe as used, a decision called "cowardly" by environmental groups that wanted it banned.

But what does giving mega-doses of BPA (or anything else, really) to a mouse or rat have to do with the real world where we take in (and rapidly excrete) tiny quantities of it?

Since BPA plastics are used to seal food cans, among other things, virtually all of us have some measurable amount of it in our bodies, albeit in miniscule amounts. Just like we have thousands of other chemicals, both synthetic and natural, floating around in there.

This fact has led groups and individuals to try to pull the wool over the eyes of those lacking a science background--that is, they imply or just assert that the presence of a chemical is necessarily related to any health consequences from it. This contradicts one of the tenets of toxicology--the dose makes the poison. It may sound trite, but it's just as true as ever.

If this were not the case, one would expect to be seeing massive health consequences for the estimated 80 thousand chemicals used in modern life today. So where are they?

I have no idea. In fact, the incidence of almost all cancers in the U.S. has been slowly drifting downward over the last thirty-five years according to the American Cancer Society. And the myth of declining sperm counts was thoroughly debunked in a Columbia University paper in 2008 and several other large epidemiological studies. The research alleging declining sperm counts used to reach this "conclusion" was flawed.

All of this brings up some practical matters. How is testing 80 thousand chemicals going to work? Should we ban all 80 thousand until they are first tested? What will it cost? Who is going to do it, and how will they measure whatever property they are looking for? At what dose? In what animal? And please believe that even if this monumental task were ever completed, there would be no shortage of borderline or ambiguous data with no clear answer. And it will still be animal data, which may or may not have any relevance to human health. Then what? How can anything useful ever come out of this?

Kristof "takes a cue from [his] experts," but I have to wonder about his choices. One of them, Dr. John Peterson Meyers, the chief scientist at Environmental Health Sciences is so afraid of BPA that he and his family stopped buying any canned food and refuses to touch receipts (many of which have traces of BPA) from gas stations or ATMs. Kinda makes me wonder if you could screw with his head by giving him a whole bunch of really bad birthday gifts and include the gift receipts, knowing he couldn't return any of them.

In the end, this is all silly. People are not dropping dead from ATM receipts or canned soup. Cancer is still cancer, but rather than the "cancer epidemic" we hear so much about, there is actually less of it than there used to be, despite the aging of our population. And if you should be in the mood to count your sperm, they will be fine too.

Health doesn't come from eliminating everything that might conceivably be unsafe from the environment. It comes from not smoking, getting vaccines, wearing seatbelts, staying in shape -- and a whole lot of luck.

Tea time.

Commemoration:

She Was Right

By Arianna Huffington

Fifty years ago, a marine biologist named Rachel Carson began publishing a series of articles in The New Yorker, sounding the alarm about the dangers of exposure to chemicals and the failure of the chemical industry and government regulators to protect people from those dangers. Later collected in the book Silent Spring, Carson's prescient insights are the subject of an anniversary feature this week by HuffPost's environmental reporter Lynne Peeples. She delivers not only a tribute to Carson but a reminder that her work is more relevant than ever.

Despite Carson's warnings, our leaders are still not doing nearly enough to regulate the potentially harmful chemicals we're exposed to every day. As Lynne notes, more than 80,000 chemicals currently used in our country have never been fully tested, so we don't even know how damaging they might be to humans or to the environment. And as Harvard Medical School's Eric Chivian explains, when it comes to determining if a chemical is dangerous, the U.S. does not put the burden of proof on those who introduce it; that burden is on the watchdogs to prove the danger, after the substance has already been introduced. Which is to say, we have it backward. We'd rather perform autopsies than biopsies. And it's yet another instance in which we're failing to keep up with the rest of the world.

Our low level of concern and urgency is especially shocking when you consider the high level of potential to harm our most precious resource, our children. Decades after Carson wrote in Silent Spring that harm from chemical exposures begins in the womb, scientists learned she was right. We now know that early exposure to toxic chemicals can impact a child for his entire life, even if the effects take decades to manifest. Even though Carson's key points have been widely affirmed by the scientific community, the pace of progress has been remarkably -- unacceptably -- slow, in large part because, as one expert tells Lynne Peeples, "things are far more complicated chemically than they were in Carson's time." And thus, harder to regulate.

Meanwhile, we are playing a dangerous game of catch-up. Just this year, the U.S. Centers for Disease Control and Prevention stated that any level of lead in a child's bloodstream is dangerous and can cause brain damage, no matter how small the amount. Today, "more American school children die of cancer than from any other disease" -- yet another quote from Carson that remains tragically true today.

For some, the signature image that shows how real the threat is to our environment is the disappearing snowcap atop Mt. Kilimanjaro. For me, it's the image of millions of kids suffering from asthma caused by the explosion of toxins in our environment, kids who are afraid to go out and play without bringing along their inhalers. But instead of a hair-on-fire response, our approach has been more like wait-and-see.

By highlighting Carson's work, Lynne Peeples reminds us that when it comes to the explosion of chemicals in our world, tomorrow is today. And what we do today will deeply affect our tomorrows -- and the tomorrows of our children.

* * *

Suggested read:

Time: Why the Federal Government Finally Acted on Chemical Safety

*

Sharing with Our World Tuesday

Please note:

I very much appreciate my articles and photos appearing on fellow bloggers' sites, popular broadsheets, and local broadcast news segments, but I would appreciate even more a request for permission first.

Thank you!