Hey, what's even better than weed killer being sprayed on crops you eventually eat? How about if it then ends up in air, water, and even rain? AWESOME. I SEE NO POSSIBLE DOWN SIDE TO THIS PLAN.

Seriously, this is pretty alarming news: Researchers from the U.S. Geological Survey have detected the active ingredient of Roundup, a chemical called glyphosate, in waterways, air, and rain. On the one hand: Those raindrops have no weeds in them, by God. On the other hand: Everything else about this.

Now, we're talking about some pretty tiny concentrations here, much less than what farmers use to kill weeds. But unless you're only breathing on alternate Thursdays, you could definitely be taking in these small doses frequently enough that they build up. A researcher at the University of Wisconsin looked at the USGS numbers and calculated that the level of contamination they were seeing could lead to enough exposure to disrupt the endocrine system in humans. 

Pesticide-exposure expert Warren Porter, PhD, professor of environmental toxicity and zoology at the University of Wisconsin, Madison, did the math. He took the air exposure numbers from the USGS study and found some reason for concern. His calculations showed that the levels found in the USGS survey could lead to accumulated levels that could alter endocrine mediated biochemical pathways, leading to obesity, heart problems, circulation problems, and diabetes. Low-level exposure to hormone disruptors like glyphosate (Roundup's main ingredient) has also been linked to weakened immune function and learning disabilities. "This study is just looking at a single day of exposure," he says. "If you consider that our body hormones work in the parts per trillion and you disrupt normal endocrine function, which tends to alter biochemical pathways, you may be flipping biological switches that have long-term impacts. No one has explored whether Roundup has epigenetic impacts which alter gene expression, possibly for a lifetime."

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Can we presume that Monsanto, which sells both Roundup and the crops treated with it, is also working on some kind of endocrine disruptor immunity drug? It seems like the kind of hat trick they'd go for.