Andrew Wetzler's Blog: Health and the Environment

Minnesota Reviews Atrazine -- And Drops the Ball

2010-03-19T16:26:42Z

For those of you who have been following the growing concerns over the widespread use of the pesticide atrazine in the United States, you probably know that EPA recently announced it was going to conduct a top-to-bottom review of the chemical’s safety (for NRDC’s comments on the EPA review, click here).*

What you may not know, however, is that states can also initiate their own reviews—federal environmental law allows states to set standards that are more restrictive than those mandated by the EPA.

Minnesota recently took this much needed step when it decided to open its own review of atrazine to determine whether tighter standards were needed. So far so good. Two months ago, Minnesota released the results of its review and invited comment. On Wednesday, NRDC submitted its comments on the review, which starts with our recent report on atrazine contamination in the Midwest, Poisoning the Well. Unfortunately, the conclusions in Minnesota’s review fall far short of the mark. Here’s the top line results of our analysis:

Minnesota minimizes much of the recent science on atrazine’s effects. This includes studies that indicate that prenatal atrazine exposure may increase risk of poor birth outcomes and birth defects in infants, as well as studies that links atrazine urine levels in farm workers and rural men to reproductive effects, such as low sperm count and motility.
The report also ignores much of the experimental literature on atrazine’s endocrine disrupting effects, including a recent study reporting that 10 percent of male frogs that were born and raised in water contaminated with 2.5 parts per billion (ppb) of atrazine grew up with female sex characteristics, had reduced levels of male testosterone hormone, reduced sperm levels, and decreased fertility.
The report mischaracterizes the economic benefits of atrazine use. Minnesota fails to discuss (or mischaracterizes) studies that predict very small crop yield losses from phasing out atrazine, as well as one study that found that, despite a ban on the use of atrazine in Italy and Germany (both corn-producing nations) since 1991, neither country has recorded any economic effects.
The report relies on inadequate and probably faulty water monitoring data to reach its conclusions. Minnesota’s review relies on the results of 2,782 samples taken from the 544 community water systems. While that might sound like a lot, it averages to only about 5 samples taken per system. Moreover, these samples were taken over a period of 9 years. This averages out to fewer than one sample per system per year. Simply put: samples taken a few times a year, or once a year, or as little as once every three years (as was the case for some systems) should not be relied on. Dangerously high spikes of atrazine can occur in drinking water for just a few weeks out of the year. If a system samples only once a year or a few times a year, it is very likely that that sample will miss the spike entirely and give the false impression that there is little to no atrazine in the water.

Hopefully, Minnesota will take these comments to heart and revise its assessment. The North Star state could sure use it.

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*Quick atrazine primer: Atrazine is used mostly on corn, sugarcane and other crops to suppress weed growth. United States farmers apply an estimated 60 to 80 million pounds of atrazine active ingredient annually. Because it is typically used in the spring before crops are planted and when rains are frequent, atrazine is often transported in runoff from fields to nearby surface waters. As a result, atrazine is the most commonly detected pesticide in U.S. waters, present in more than 75% of stream samples and 40% of shallow groundwater samples in agriculture areas across the United States. It is an endocrine disrupting chemical, meaning that it can disrupt normal hormone function in a wide variety of organisms, including people.

From Pipes to Polar Bears

2010-02-01T17:51:07Z

Today’s Chicago Tribune features a long story by Michael Hawthorne about the metal plating industry and their ongoing practice of dumping pollutants such as perfluorinated compounds (PFCs) into the sewers of major cities like Chicago and Cleveland. The PFCs are then discharged, untreated, into nearby rivers, lakes and streams. PFCs are nasty stuff, and have been linked to a wide variety of health concerns, in both humans and animals. Ok, you’re probably thinking, sounds bad, but what does this have to do with polar bears?

Well, PFCs are one of several “persistent organic pollutants” or “POPs”--which also includes chemicals such as polychlorinated biphenyls (PCBs), chlordanes (CHL), DDT and its metabolites, and polybrominated diphenyl ethers (PBDEs)--that don’t readily degrade in the natural environment. As Hawthorne notes, because POPs are so long lasting, once they are emitted into the air or the water they move around, and a lot of them end up in the Arctic. They also tend to bioaccumulate. That is, concentrations of POPs are higher in animals as one moves up the food chain from, for example, fish, to seals, to things that eat seals. And what eats seals? Polar bears.

A 2005 study showed that levels of one type of PFC--perfluoroalkyls, which are associated with fetal toxicity and other effects in mice and rats--have risen exponentially in polar bears from two disparate locations in the North American Arctic. A more recent study showed this same trend in East Greenlandic polar bears. If these current trends continue, scientists expect the lowest-adverse-effect level detected for rats and monkeys for these chemicals could be reached in East Greenland as soon as 2014.

And its not just polar bears at risk. Studies show that Inuit people in Nunavut, Canada, are exposed to PFC, largely from consumption of traditional food such as seals, beluga whales, and caribou. While exposure levels still appear to be low, these are not compounds that are produced or emitted anywhere near the Canadian Arctic. And, as pointed out above, their levels seem to be increasing.

All of which is a helpful, if chilling, reminder about the old environmental saw: think globally, act locally. When it comes to modern chemistry, what we throw into the sewers of Chicago can very well end up in the stomachs and breast milk of people and animals thousands of miles away.

EPA Decides to Take a New Look at Atrazine

2009-10-07T21:33:39Z

Good news: today the Environmental Protection Agency announced that it will initiate a review of the health and environmental effects of atrazine, one of the most widely used pesticides in the United States.

The review will take about a year and will begin with a comprehensive look at the emerging science about atrazine’s potential human health effects. As an “endocrine disruptor” (meaning that it’s capable of disrupting normal hormonal functions) a host of studies have potentially linked atrazine to a wide variety of health effects from various types of cancer to poor sperm quality in humans. Atrazine can also be devastating to aquatic ecosystems. At extremely small doses, atrazine has been shown to turn frogs into hermaphrodites. It has been linked to sever organ and limb deformities and life-threatening behavioral changes in amphibian species, and it can disrupt fish behavior and the productivity of aquatic plant life.

EPA’s announcement comes just six weeks after NRDC released its report, Poisoning the Well, which brings together EPA data on atrazine contamination in surface waters throughout the Midwest and in drinking water. We show that the standards applied under the Safe Drinking Water Act do little to protect the public against alarmingly high spikes of atrazine in their drinking water and that the surface waters of the Midwest are similarly subject to very high levels of contamination.

NRDC will, of course, be fully engaged in the EPA’ review. It’s high time that the United States seriously consider doing what Europe did years ago: ban the stuff. In the meantime, the Obama Administration (and EPA Administrator Lisa Jackson) deserves a lot of credit for having the courage to take this important first step.

Poisoning the Well: atrazine is scary, and it’s everywhere

2009-08-23T20:58:57Z

Years ago, when I first moved to the Midwest (Columbus, Ohio, to be more precise) from California one of the first things I noticed was the corn. Not corn fields, mind you, although there were plenty of those, but corn in the grocery store, in farmers’ markets, and along road-side stands. On the whole, Midwest produce doesn’t really hold a candle to California produce but, oh, the corn! Sweet, juicy, and luscious, it was a revelation to a city kid like me who never really went for corn-on-the-cob.

At the time, little did I realize what was being used to cultivate so much of that corn: atrazine, a truly nasty chemical. As detailed by Charles Duhigg in a New York Times article published today, atrazine is a herbicide, applied in the spring to kill weeds before crops begin to grow. It’s also an endocrine disrupter, meaning that it can interfere with normal hormone activity. When organisms are exposed to atrazine, particularly at sensitive periods in their development, bad things happen. Exposure as low as 0.1 parts per billion have been shown to cause the development of female sex characteristics in male frogs and the development of eggs in male frog testes. (As Stephen Colbert recently put it when interviewing Nicholas Kristof about endocrine disruptors, “you’re saying something is happening to fish junk?”)

There is also evidence that may link atrazine to low sperm counts in farm workers, cancer in laboratory animals, and human cancers, such as non-Hodgkin’s lymphoma.

In the United States alone, an estimated 60 to 80 million pounds of atrazine are applied to corn, sugarcane, and sorghum crops every year. Much of it in the Midwest. Atrazine ends up in our rivers, streams, creeks and lakes; even in our drinking water. Because of the inability to keep atrazine out of surface waters, the European Union completely banned the stuff in 2004.

NRDC’s report, Poisoning the Well, helped to inform the Times story and we will be briefing the press on its findings Monday. The report detail the shocking extent of atrazine contamination in surface waters and drinking water systems throughout the central United States. Our report brings together data from two different EPA monitoring programs, explains the ways in which the federal government has failed to properly regulate this chemical, and recommends solutions. We also have an interactive map available online. We’ll be briefing press about the report tomorrow. Check it out.

Alligators to the rescue

2008-06-02T15:47:49Z

Last week I linked to one good reason for saving endangered plants and wildlife: wonder. But there are more practical reasons as well. As I've noted before, not least of these reasons is the fact that many of the pharmaceuticals we take for granted (digitalis is one example) are derived from the other creatures with whom we share the earth. The latest potential contributor to humanity's well being: the American alligator.

It turns out that alligator blood contains powerful peptides, a kind of protein, that scientists believe are an adaption to the need to fight off infection in a hot, wet, tropical environment (getting cut is an occupational hazard if you're an alligator). These peptides have already shown promise in the lab for stopping infections caused by severe ulcers, burns and--most promisingly--antibiotic resistant "superbugs," such as MRSA.

All of which is somewhat ironic, of course, considering that we nearly drove alligators to extinction in the first half of the last century. It wasn't until we protected alligators under a predecessors to the Endangered Species Act--a law which sees the wisdom in preserving all forms of life, no matter what its reputation--that alligators began to make a comeback.

(Hat tip: ESAblawg).

Global Warming--Now, With Mercury!

2008-03-01T17:16:50Z

For years, scientists have been concerned about the substantial increase of mercury concentrations in Arctic marine mammals such as polar bears, beluga whales, and seals. In some places in Canada, for example, levels of mercury in the tissue of marine mammals has quadrupled in the last twenty-five years. Mercury is a potent neurotoxin that can result in a wide variety of health effects in animals and people, and pose a particular risk to pregnant women and young children. Most global mercury pollution comes from coal fired power plants, which release mercury into the air. Other significant sources are industrial processes such as chemical manufacturing, battery production, and gold mining.

Today's Winnipeg Free Press reports that changes to the Arctic's food web, such as melting sea ice caused by global warming, may be one of the primary causes of mercury contamination of marine mammals.

[R]esearchers now believe the increasing levels found in beluga whales are actually due to rising temperatures and disappearing sea ice, which have boosted the productivity of the northern seas by creating a warmer, brighter and more nutrient-rich environment for tiny plants and animals to grow.
According to the theory, new sources of food in an increasingly ice-free Arctic are forcing larger predators to change their feeding behavior, creating more links in the Arctic food chain.
That means more mercury gets concentrated at the top of the food chain, even though the overall amount of mercury in the ecosystem has not increased very much.

This research is intriguing and is consistent with predictions in other studies. Of course, the problem of mercury pollution and global warming goes hand-in-hand: ultimately, the best way to decrease global mercury pollution is to reduce our dependence on dirty sources of fuel like coal. If we did that, we would also be taking a big step toward controlling global warming, thus slowing down the very changes to the Arctic ecosystem that may be driving up mercury contamination of marine mammals. Another thing we can do here in the United States is to follow the example of the European Union and ban on the export of mercury. A bill to do just that has already passed the U.S. House of Representatives and companion legislation is awaiting action in the Senate.