Plenty of nonsense

August 21, 2008

Plenty Magazine’s Jessica A. Knoblauch is on a mission to rid the world of vinyl, and she won’t let facts get in her way, or science. Yesterday it was vinyl window shades, today it’s vinyl mattresses:

Most students don’t get many zzzzz’s during the school year, so when the head does finally hit the bed it’s nice to know you’re not sleeping on a bunch of chemicals. …And since dorm beds aren’t exactly 5-star quality, pad up your rock hard bed with natural wool mattress pads that are fluffy, absorbent and fire-retardant. Unlike the regulation vinyl dorm mattress, these pads won’t force you to “go to the mattresses” with hormone-disrupting phthalates.

Not only is there no evidence that one can absorb any phthalates from a vinyl mattress from sleeping on one, but even if you did spend hours licking your mattress (treating it as a giant pacifier) there’s still no evidence you’d absorb any specific phthalate in sufficient quantities to experience any negative health effects.

The evidence that some phthalates might be associated with endocrine disruption comes from a study of Chinese vinyl workers, who were exposed to massive quantities of the chemicals in the workplace, and who had reduced sperm counts. Even then, the research did not find that they had impaired fertility.

Vinyl window shades are not going to make you fat

August 20, 2008

Increasingly, environmental journalism is taking on the color of naivity. Take this entry in Plenty Magazine’s “Your Daily Green Bit,” written by Jessica A. Knoblauch, which focuses on the risks of phthalates in vinyl window shades:

the relatively low cost of vinyl shades doesn’t outweigh the potential health affects of surrounding yourself with chemical-laden sun screens. Besides, surviving the school year is hard enough without worrying your window coverings are making you fat.”

Let’s start with the obvious mistake: the research pointed to in the link is about Bisphenol A (BPA) and Perfluorooctanoic Acid (PFOA) and rodent studies; there is no mention of phthalates. Second, there is no scientific justification for thinking that sleeping in a room with a vinyl shade will make you fat based on these or other studies.

There is at least one study which showed that several phthalate metabolites had “statistically significant positive correlations with abdominal obesity and insulin resistance in adult U.S. males,” which means that the fatter and more insulin resistant the man, the greater the quantity of phthalate metabolites in his urine.

But the simple fact of a correlation doesn’t mean that phthalates caused the obesity. It could be the case that men who are fat retain more phthalates than men who are not; in fact, the authors of the study listed seven limitations on the interpretation of their findings, among which include the study being cross-sectional, so it is only a snapshot of at a single point in time and cannot determine causality; and the database they used contained no data on sex hormone levels, thereby limiting examination of the mode of action by which they hypothesize that phthalates might cause obesity. (This, naturally, didn’t stop journalists from touting a connection).

In order for any chemical to be implicated as a factor in obesity, there has to be a route of exposure. So there would have to be some way of getting the chemicals out of the blinds and into the bloodstream for anything to take place. The studies cited by Knoblauch involved administering the chemical to pregnant rodents – and then seeing what the effect is in their offspring.

The article doesn’t say whether this was done by feeding (oral exposure) or in utero (by injection), but as BPA loses all estrogenic capacity in humans after oral exposure, the test involving BPA would have to have been by injection. So, even if you spend hours licking a vinyl blind or sniffing vinyl blinds in direct sunlight, whatever BPA you might absorb (and where is the evidence that BPA offgases in sunlight?) is not going to disrupt your endocrine system, make you fat, or reveal anything other than the likelihood that you need psychological help.

Moreover, the study cited on BPA used mice. The European Union’s risk assessment specifically noted that mice process BPA in a way that is so different from humans these kinds of studies have no relevance to human health. As for PFOA, studies of workers and other populations exposed to high levels of PFOA have not found any connection between exposure to the chemical and obesity.

The one thing this article does manage to demonstrate is that Plenty’s “Your Daily Green Bit” should be taken with a heaped serving of skepticism.

A first step on the road to drug coverage recovery

August 18, 2008

Maia Szalavitz

Although the New York Times loves a good, unmitigated drug scare, its Sunday front-page story on methadone deaths was unusually balanced. Past Times coverage of the painkiller Oxycontin often included stories without a single quote from a pain patient who wasn’t a drug abuser (actually, the majority of patients). But this piece spotlighted patients who were helped as well as those who were harmed, showing that opioid drugs like methadone and Oxycontin aren’t just evil killers that needed to be restricted as much as possible.

Could the story have looked into the role the media played in driving doctors to prescribe methadone instead of the safer Oxycontin after the press demonized that drug? That would have given some much-needed perspective to prescription abuse problems, albeit at the expense of implicating the media, including the New York Times itself.

Could it have placed more emphasis on the fact that the vast majority of methadone deaths do not occur among people who take the drug as prescribed? Yes – the failure to tease out the numerical difference between death due to mixing methadone with other drugs and death due to methadone alone makes it difficult to determine whether more addicts are abusing methadone or more pain patients are suffering from accidental overdoses.

Could the Times have acknowledged the difficulty many patients have with getting doctors to prescribe opioids for chronic pain at all? Absolutely.

But including both sides of the story is a welcome change from prior coverage, and perhaps it marks the belated recognition that demonizing particular drugs one after another is not a sensible strategy for covering the issue.

The FT Fact Checks Prince Charles’ GM Food Fears

August 14, 2008

The droit de seigneur of His Royal Highness, the Prince of Wales, does not quite entitle him to his own facts, as the FT notes today:

Prince Charles, furthermore, made a number of assertions that are simply wrong. The water table is falling in the Punjab, he said, because of GM crops. Nonsense. The water problems are the result of subsidies on rice and electricity. The subsidies encourage the cultivation of rice which – GM or not – requires a paddy field filled with water. Since electricity is free to the farmers, they leave water pumps on constantly and bleed their aquifers dry. The Punjab’s problems are caused by the Punjab’s politicians.

The prince also blamed the high salt levels in the soil of Western Australia on the excesses of modern farming. But salination there is caused by deforestation and geology. It has always been a problem for Australian farmers and was first noted in the 1920s (when Monsanto, the GM food giant, was still making rubber and aspirin).

The prince has done good works through his charities, but he should be guided by science, not superstition. “Let them eat organic shortbread” is no answer to rising food prices.


Memo to New York Times Copydesk: HIV Prevention Means *Not* Sharing Needles…

August 6, 2008

Maia Szalavitz

Here’s a whopper from today’s New York Times, in an article on how the world is failing at HIV prevention by failing to use measures to push behavioral change:

Dr. Adeeba Kamarulzaman of Malaysia said that outside Africa, about 30 percent of H.I.V. infections were among intravenous drug users. But because of stigma and a lack of resources, the world is failing to provide measures like methadone and needle sharing that can help such people.

Somehow, we doubt Dr. Kamarulzaman meant that H.I.V. positive Africans should share needles, and as this is paraphrase and not direct quotation, there is no reason not to correct what is, from a medical perspective, an example of misspeaking. So we are left with the irony that a doggedly literal-minded copy desk has managed to give really bad, and possibly fatal, advice in an article supposedly about the failure to advise people how to avoid contracting H.I.V…

What Makes Some Voles Monogamous And Why You Should Care

August 6, 2008

STATS Maia Szalavitz reports on MSN Health and Fitness about some interesting research showing that the biological basis for monogamy lies in the hormone and neurotransmitter oxytocin:

In prairie voles, oxytocin seems to wire in a connection between one particular partner and pleasure (another chemical, vasopressin, is needed as well in males); prairie voles are monogamous creatures.

But promiscuous montane voles don’t have much of these crucial chemicals in their brain’s pleasure areas—to them, any partner goes.

So, at least in voles, oxytocin and vasopressin are the stuff that love is made of.

There has been much speculation that humans taking oxytocin together would fall in love—but in experiments with hundreds of subjects, so far this hasn’t happened, in either women or men…”

This is probably a good thing: people forging relationships on the basis of having consumed a drug sounds like an awful idea. But this doesn’t mean that research into oxytocin is a waste of time – it may not be a love drug, but it might just help people socialize… more

What’s Lurking in Your Countertop? Um, Probably Nothing

August 1, 2008

After warning us about the dangers of walking barefoot in the park (grass can cut your feet allowing parasites to enter your body, apparently), the Neurotic Times New York Times recently decided to investigate whether leaning on your granite countertop will give you lung cancer.

The problem is that natural stone can contain radioactive elements. Mother Earth, having been created in an enormous burst of energy, is, unfortunately, radioactive. As these radioactive elements decay, they release radiation in the form of rays; but if the element is uranium, it decays first into radium which in turn creates a gas called radon. If you breathe air containing radon you increase your risk for lung cancer. The risk exists wherever you build a house, which is why it is important to have your house tested, especially if you live in high radon areas.

But there’s a difference between the earth’s crust and a granite slab in your kitchen, and the question is can a granite countertop release enough radiation to pose a risk? The Times story begins with an anecdote about a pediatrician, Dr. Lynn Sugarman, telling her visiting pregnant daughter to stay away from the kitchen counter after a routine radon detection signaled radiation at ten times the level in the rest of the house. She then ripped out the granite countertop and sent it off for analysis: it turned out to contain high levels of uranium.

According to the Times, the radon readings in Dr. Sugarman’s kitchen were 100 picocuries per liter, compared to 6 picocuries per liter in her basement.

And this is where things become confusing. Both Consumer Reports and The Environmental Protection Agency suggest that fears about granite countertops have been overhyped – and Consumer Reports tracks some of the most damning information to rival, non-granite countertop manufacturers. There have been multiple tests of many different types of granite and emissions have been found, in almost all cases, to be negligible.

In a study of Cold Spring Granite Company building stone samples, for example, Daniel J. Steck, Ph.D. a physicist at St. John’s University, calculated the radon exposure from granite building materials in a range of typical dwellings and found that it amounted to less than 1 percent of the overall concentration in a home.

In fact, most of the Times article notes how much of a risk granite isn’t in terms of radiation and radon:

David J. Brenner, director of the Center for Radiological Research at Columbia University in New York, said the cancer risk from granite countertops, even those emitting radiation above background levels, is “on the order of one in a million.”

So how could Dr. Sugarman’s countertop sound like an atom bomb? In fact, if the ventilated air in the kitchen was registering 100 picocuries of radon per liter, Dr. Sugarman was absorbing a terrifying amount of radon – enough to raise her risk of getting lung cancer to one in seven, based on the EPA’s risk exposure guidelines. (And if she smoked on top of that, the statistical risk is a virtual guarantee that she would develop or should have already developed lung cancer).

That the Sugarman household was not hermetically sealed in a plastic bubble by the EPA suggests that the Times omitted some crucial information about how radon is emitted from stone, namely that it diffuses rapidly in air. In other words, the reading of 100 picocuries per liter is the emission rate but not the airborne concentration level. This is an important distinction. It’s also important to note that a cubic foot is 28 liters, so a 1,000 square foot home with ten foot high ceilings would contain over a quarter of a million liters of air. As Columbia’s Brenner told WebMD, “Even a countertop that is ten or a hundred times higher than average is going to constitute a minimal contribution of radon.”

Without knowing the airborne concentration level in Sugarman’s kitchen, it is impossible to know how much of an actual risk her countertop presented, and whether having it ripped out was an over-reaction; and this in turn speaks to the importance of how you measure risk and how you deploy anecdotes in journalism. The Sugarman countertop gives the story much needed drama, but only because it is presented in a way that exaggerates the risk.

But his cuts both ways: the other troubling question raised by the Times article is whether the air content measured in Dr. Sugarman’s basement was, in fact, 6 picocuries per liter; if so, then the EPA recommends she take action to fix her home immediately.


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