Dataset of the Day: Atrazine in our Drinking Water

Atrazine, a herbicide banned in the European Union in 2004 but still widely used in the US, has recently been in the news due to lawsuits and the release of EPA’s atrazine monitoring data. Thanks to the Huffington Post who made the data public, GeoCommons now has in Finder! annual averages and peaks for atrazine levels as well as the most recent results for each year from 2003 to 2008.

Syngenta, the leading producer of atrazine, claims that “water systems in the U.S. are safe where atrazine is concerned. Over the last three years, no water systems in the U.S. had atrazine levels in their drinking water that exceeded legal limits.”
However the recently released data do not agree and neither does the NDRC. According to them “three water systems had running annual averages for atrazine in finished (tap) water that exceeded the 3 ppb drinking water standard” and “54 water systems (39 percent) had a one-time peak atrazine concentration above 3 ppb”. The NDRC also suggests that the current standards by the EPA which focus on annual averages ignore the more alarming peaks. An analysis of the dataset supports that concern. This graph of by monthly levels in 2008 shows dramatic peaking of atrazine levels in the water for almost 4 months coinciding with planting season when atrazine is applied.

The map below shows average atrazine levels in parts per billion for finished water in the areas studied for 2008. This next map shows the peak levels for each area for 2008. This map from the USGS shows the average annual use of Atrazine for 1997. To see more data for 2008 or for other years click here.