It’s been a rainy spring here in the Midwest and that mean worries about flooded basements, streets, and towns. Many of our streams and creeks are bloated by runoff from nearby fields. Unfortunately, a lot of those fields have been treated with atrazine, a herbicide applied in the spring to kill weeds before crops (mostly corn) begin to grow. Atrazine is one of the mostly widely used pesticides in the world. In the United States alone, between 60 and 80 million pounds of atrazine are used each year and atrazine is the most commonly detected pesticide in U.S. waters. Today in Missouri we got a taste of the consequences of this widespread use.
From the Kansas City Star:
Authorities are warning Drexel, Mo., residents not to drink the water there after routine testing revealed high levels of the herbicide atrazine.
Spikes like this--in this case over 10 times the federal annual exposure limit--are not at all uncommon in the Midwest, as our two reports, Poisoning the Well, discussed. Below is a map of Missouri atrazine spikes from our 2009 report (showing atrazine levels from 2005-2006). Note that only data from watersheds that were actually tested are shown--that is, far more watersheds than illustrated here were probably contaminated:
These kinds of exposures are particularly disturbing because atrazine acts as an endocrine disrupter, potentially altering normal hormone functions in a whole range of organism, including people. Want some examples? A recent study reported that 10 percent of male frogs that were born and raised in water contaminated with low doses atrazine grew up with female sex characteristics, had reduced levels of male testosterone hormone, reduced sperm levels, and decreased fertility. Another recent study found that fish exposed to atrazine had impaired egg production and abnormalities in their reproductive organs. As for people, studies indicate that prenatal atrazine exposure may increase risk of poor birth outcomes and birth defects in infants; other studies have linked atrazine urine levels in farm workers and rural men to low sperm count and motility.
EPA is currently conducting a review of atrazine’s safety. I’m hoping that next time the spring rains come to the Midwest we’ll have one less thing to worry about.