Organic Consumers Association

Campaigning for health, justice, sustainability, peace, and democracy
  • Purple flower
  • asian farmer
  • veggie market
  • african wheat farmer
  • woman harvesting
  • allium
  • 3 lambs
  • apple
  • apple
  • apple vendor
  • apples in basket
  • apples on tree

Corn Herbicide Atrazine Damages Human & Animal Immune System

Pesticides have wreaked havoc on global amphibian populations, and now new
> evidence suggests that the problem may be even worse than thought. One of
> the most common herbicides—atrazine—appears to have an added deadly effect:
> It makes tiger salamanders more vulnerable to certain infections. Because
> atrazine also has deleterious effects on humans and other mammals,
> researchers fear this new effect on amphibians may be a harbinger of a
> larger problem for other species.
>
> Atrazine is the second most popular agricultural pesticide in the United
> States, used primarily to control weeds on corn, sugar cane, and
> residential lawns. The compound mimics the hormone estrogen, and over the
> past 10 years, scientists have noticed that frogs and other amphibians
> exposed to the herbicide develop deformed genitalia and smaller voice
> boxes, making mating calls softer and reproduction impossible. Atrazine was
> introduced in 1958, and scientists started noticing upticks in fungal and
> viral diseases in exposed animals in the late 1990s. Studies confirmed that
> atrazine suppresses the immune system, but whether this led to increased
> infection rates remained a mystery.
>
> To solve the conundrum, biologists Diane Denise Forson and Andrew Storfer
> of Washington State University in Pullman took a closer look at the tiger
> salamander, a small amphibian commonly found in marshes and ponds around
> the globe. Tiger salamanders tend to live in areas exposed to atrazine, and
> over the past few years biologists have noted a rise in their
> susceptibility to the Ambystoma tigrinum virus (ATV), which causes internal
> hemorrhaging and death. In the lab, the researchers exposed 384 tiger
> salamander larvae to levels of atrazine similar to those found in nature,
> and then introduced ATV for 3 days at the 12-week larval stage. (Atrazine
> is commonly sprayed in the spring, during this stage of development.)
>
> Tiger salamanders exposed to atrazine were twice as likely to become
> infected with ATV than were those not exposed to the herbicide, the team
> reports in this month's issue of Ecological Applications. In addition, when
> combined with sodium nitrate, a type of fertilizer, atrazine lowered the
> levels of white blood cells that fight disease by nearly 20%. "Because
> amphibian skin is permeable, toxins can be absorbed directly into the
> bloodstream," says Storfer. "Their eggs are also permeable to environmental
> toxins, which makes them indicators of environmental contamination," adds
> Forson.
>
> "This is one of the few, rare examples of a toxin causing an indirect,
> increased susceptibility to infection," says Andrew Blaustein, an ecologist
> at Oregon State University in Corvallis. However, the specific mechanism by
> which immunosuppression occurs still needs to be established, says Tyrone
> Hayes, a biologist at the University of California, Berkeley. This is
> especially important because atrazine has been associated with breast and
> prostate cancer in humans, he says.
>
> Related site
>
> # Environmental Protection Agency report on atrazine and amphibians

Like OCA on Facebook

Translate

English French German Italian Portuguese Russian Spanish