Atrazine is an herbicide used to control weeds primarily on corn, sugar, rape-seed (canola), soybean, lupine, pine and eucalyptus crops. It is also used to treat turf/sod and has been found to be the most common pesticide contaminating drinking water in the US.
The EPA has classified it as safe for humans.
They also state in their 2016 Refined Ecological Risk Assessment for Atrazine: “it is difficult to make definitive conclusions about the impact of atrazine at a given concentration but multiple studies have reported effects to various endpoints at environmentally-relevant concentrations.”
In 2003, the Agency for Toxic Substances and Disease Registry (ATSDR) stated that atrazine is “currently under review for pesticide re-registration by the EPA because of concerns that atrazine may cause cancer” – not enough information was available to “definitely state whether it causes cancer in humans.”
The ATSDR says atrazine can alter the “way that the reproductive system works. Studies of couples living on farms that use atrazine for weed control found an increase in the risk of preterm delivery, but these studies are difficult to interpret because most of the farmers were men who may have been exposed to several types of pesticides. Little information is available regarding the risks to children, however “[m]aternal exposure to atrazine in drinking water has been associated with low fetal weight and heart, urinary, and limb defects in humans”.
One study on the effects of atriImr on fat head minnows concluded: “Environmentally-relevant concentrations of atrazine have significant effects on reproductive output in fathead minnow.”
References
Study: Atrazine reduces reproduction in fathead minnow (Pimephales promelas)
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