More on Atrazine

About a week ago, I posted on a New Yorker article about Atrazine - a widely used herbicide in agriculture.  After reading the article, I was a bit dismayed about the ability of science to resolve the controversy, writing:

More disconcerting still is what this says for the ability of science to resolve disputes about knowledge.  Whether atrazine causes abnormalities in a particular type of frog at a certain dosage should be one of those questions science can answer.  Either atrazine causes these effects or it doesn't.  This isn't one of the mysteries of the cosmos.  This isn't macroeconomics.  Yet, there are apparently findings on both sides of the issue (Note: I have't personally delved into the scientific literature on this particular matter in any detail). 

Well, I spent a bit more time digging into the issue, and the science on frog abnormalities seems much more settled than the New Yorker article let on.

It seems the defining study on the issue is the so-called Kloas study.  Here is what the New Yorker said about it:

The Kloas study was the most comprehensive of its kind: its researchers had been scrutinized by an outside auditor, and their raw data turned over to the E.P.A. But the scientists wrote that one set of studies on a single species was “not a sufficient edifice on which to build a regulary assessment.” Citing a paper by Hayes, who had done an analysis of sixteen atrazine studies, they wrote that “the single best predictor of whether or not the herbicide atrazine had a significant effect in a study was the funding source.”

While saying the Kloas study was the "most comprehensive", the article immediately  cites skepticism and immediately brings up the issue of industry funding. It seems to me an attempt to downplay the significance of this particular study and it's findings.

From what I can gather, the Kloas study (a long white paper about it is on the EPA web site) is by far the largest and most careful study on the issue (some additional background on it can be found in this article in the journal Environmental Science and Technology).  The study was mandated by the EPA because it felt that there were too many flaws in previous studies to make a definitive judgement.  Syngenta (the maker of atrazine) funded the study (because the EPA mandated they do so), but it was carried out by two independent laboratories, one in Maryland and one in Germany (under the supervision of the scientist Werner Kloas, which is where the study gets its name).  The study followed protocol set up by the EPA scientific advisory panel.  Data collection was audited and overseen by the EPA; the data was analyzed by a third party, which did not know the particular identify of each treatment, and the data itself is available to other researchers via the EPA.

The study employed over 1,000 frogs in each location.  There were five treatment groups, which varied the level of Atrazine from 0.01 to 100 parts per billion.  There was also a conventional control (with no Atrazine).  Interestingly, there was also a "positive" control - one group of frogs was given 17β-estradiol - a compound known to cause sexual abnormalities in frogs.  The idea with this "positive" control was to determine whether the conditions were such that abnormalities could develop (or were not being prevented via some other choice of the experiment environment).

Here are the results:  The "positive control" using the compound known to cause abnormalities, indeed caused a statistically significant rise in abnormalities.  However, there was no consistent statistically significant evidence that Atrazine caused abnormalities - either it's presence or in a dose-response fashion.  The EPA concluded (see page 115):

Because of the experimental design protocols and quality control of the [Kloas] studies, the data are sufficiently robust to outweigh previous efforts to study the potential effects of atrazine on amphibian gonadal development.

Based on the negative results of these studies, the Agency concludes that it is reasonable to reject the hypothesis formulated in the 2003 SAP that atrazine exposure can affect amphibian gonadal development. The Agency believes at this time, there is no compelling reason to pursue additional testing with regard to the potential effects of atrazine on amphibian gonadal development.

What about the previous studies showing effects?  Typically, such studies: 1) used a smaller sample size, 2) did not study whether there was a dose-response relationship, 3) did not utilize a proper control group (or "positive" control like the one described above), and/or 4) have not made their data available to other researchers.  In several places, the EPA has commented on these weaknesses, and on the inability to get specific data from researchers claiming ill effects.

One of the things that bothered me about the New Yorker article was the sense that science could not settle such an issue. I wrote:

But, I also fear this is part of an attempt to undermine the ability of scientific inquiry to settle empirical disputes. . . I hold out hope that science can, indeed, provide knowledge for those willing to follow the evidence where it leads.  Otherwise, every issue is simply a PR battle.

I have no idea whether Atrazine might cause other deleterious effects, and I cannot condone Sygenta's alleged actions against Hayes.  Nor can I condone his alleged actions against employees of Synenta. But, it seem to me the science has provided us a reasonably good answer to the question of whether Atrazine causes frog abnormalities at levels below 100ppb.  It is a shame that the New Yorker let telling a good story get in the way of this fundamental fact.   

How problematic are food deserts?

Not very according to this piece in Slate:

Unfortunately, more fresh food closer to home likely does nothing for folks at the bottom of the socioeconomic ladder. Obesity levels don’t drop when low-income city neighborhoods have or get grocery stores. A 2011 study published in the Archives of Internal Medicine showed no connection between access to grocery stores and more healthful diets using 15 years’ worth of data from more than 5,000 people in five cities. One 2012 study showed that the local food environment did not influence the diet of middle-school children in California. Another 2012 study, published inSocial Science and Medicine, used national data on store availability and a multiyear study of grade-schoolers to show no connection between food environment and diet. And this month, a study in Health Affairs examined one of the Philadelphia grocery stores that opened with help from the Fresh Food Financing Initiative. The authors found that the store had no significant impact on reducing obesity or increasing daily fruit and vegetable consumption in the four years since it opened.

and

Earlier research suggesting that better fresh-food access improves diet and would therefore improve the health of people living in poverty was drawn from small samples or looked at store availability in narrow geographical slices—often without information about how or where the people who lived there shopped. “They never link the neighborhood characteristics to actual individuals,” explains Helen Lee, author of the Social Science and Medicine study. “Without that, all you have is speculation.”

Lee also notes in her study that, on closer inspection, food deserts don’t actually exist in the U.S., at least not as a national problem—on average, poor neighborhoods have more grocery stores than wealthier neighborhoods.

The writer concludes on a note which which I agree.  The real issue here probably isn't access to fruits and veggies.  These are simply symptoms of a larger problem.  Poverty.  Alas, solving the problem of poverty is no easier or no less complex than solving the problem of obesity.  But, if you could made headway on poverty, I'd argue people would have a greater incentive to consider their own future health outcomes.  

Big Food = Big Tobacco?

From Politico:

Lawyers are pitching state attorneys general in 16 states with a radical idea: make the food industry pay for soaring obesity-related health care costs.

It’s a move straight from the playbook of the Big Tobacco takedown of the 1990s, which ended in a $246 billion settlement with 46 states, a ban on cigarette marketing to young people and the Food and Drug Administration stepping in to regulate.

Who is behind the action?

McDonald’s [not be be confused with the food company by the same name] law firm has allied with a number of well-known obesity and diabetes researchers, including Barry Popkin at the University of North Carolina Chapel Hill, Robert Lustig at the University of California San Francisco and economist Frank Chaloupka at the University of Illinois at Chicago, to help hash out the strategy. . . . “We need policy to change,” said Lustig, who recently got a law degree and launched a nonprofit to continue his advocacy. “I think we’re going to have to battle [the food industry] like we battled tobacco.”

Some are skeptical:

James Tierney, director of the National State Attorneys General Program at Columbia Law School and former attorney general of Maine, laughed when asked about the proposal.

“It’s just not going to happen,” said Tierney, who noted that tobacco companies lied about the health effects of their products for decades. “The food industry doesn’t deny that eating lots of food causes obesity.”

Others are cynical:

The proposal drew ire, in part, because it would rely on a contingency fee agreement, which allows a private firm to do legal work for attorneys general offices in exchange for a cut of the settlement. It’s an increasingly common practice because it allows cash-strapped AG offices to tackle expensive litigation without taking as much risk.

“Pay-to-play relationships between [plaintiff’s attorneys and attorneys general] that exchange campaign contributions for lucrative government lawsuit contracts mean the food industry has a big target on its back,” said Lisa Rickard, president of the U.S. Chamber Institute for Legal Reform

February 2014 Food Demand Survey (FooDS)

The latest release of the monthly Food Demand Survey (FooDS) is now up.

Perhaps not surprisingly, given the Super Bowl earlier this month, consumer willingness-to-pay (WTP) for chicken wings was up 11% this month.  Consumers also appear to be poised to spend more on food away from home this month compared to previous months.  

We repeated a question we asked last month on trust in information about meat and livestock from different sources.  

In particular, we asked, “How trustworthy is information about meat and livestock from the following sources?” Fifteen sources were listed (the order randomly varied across respondents), and respondents had to place five sources in the most trustworthy category and five sources in the least trustworthy category. A scale of importance was created by calculating the proportion of times a meat and livestock information source as ranked most trustworthy minus the proportion of times it was ranked least trustworthy.

This month, we added a question asking how much people knew about each source of potential information (on a 1 to 5 scale).  When you combine those two, the following emerges

People have a high level of trust and knowledge of federal regulatory agencies (USDA and FDA).  Although people say they know companies like McDonald's and Tyson, they place a lower level of relative trust in information about meat and livestock from them.  The New York Times, University professors, and Chipotle have relatively low trust and low knowledge.  

Interestingly, being more familiar with a source does not appear to make one more or less likely to trust the source (the correlation between the two measures is almost zero at 0.03).  

I suppose, as an organization, the "ideal" place to be on this graph is to be highly trusted and well known.  What if an organization wants to become more trustworthy?  I suspect that's harder to do for entities that are already well known - like McDonald's or Tyson.  Plus, anytime one has a vested interest in an outcome, their information is unlikely to be as credible as sources with no (apparent) conflict of interest.  That's why it surprises me a bit University professors don't score a bit higher on the trust scale. Maybe people just don't think we know much about meat and livestock (but that's why I picked two Universities that were likely to differ in this regard).  A lot of open questions here. 

What Message is General Mills Sending with Cheerios?

Julie Gunlock had an interesting editorial in the USA Today on General Mills decision to go "GMO free" with Cheerios.  She points out the tough pickle food companies are finding themselves in:

It is understandable that food companies are desperate to find a way to please their critics and reach détente with the powerful anti-GM movement. Yet, it appears these companies have settled on a strategy combining meek contrition (we're sorry we use perfectly safe GM ingredients) and appeasement (we'll get rid of perfectly safe GM ingredients in some…but not all…products). This squishy and schizophrenic policy will accomplish one thing: it will make the problem much worse.

For starters, while General Mills publicly states on its website that the company agrees with the wide consensus among scientists that GM ingredients are safe, the change to Cheerios sends a very different message to consumers: We've made the product safer. Do they mean to suggest Cheerios was previously unsafe.

From a business standpoint, by suggesting Cheerios has been made safer, the company puts its other products — those that still contain GM ingredients — in a bad light. The company might be spinning this as providing consumers more choices, but organic cereals (which cannot contain GM ingredients) have been available for years. Cheerios is hardly breaking ground.

I'm not sure I'd expect food companies to make a principled stand for scientific evidence when they could make money doing otherwise.  However, as Julie points out, it isn't even all that clear that this move is in the long-term best economic interest of the company even if it does cause a quick, short term bump in market share.