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Well, it’s not the lawn, exactly, but the country’s most widely used weed killer that French scientists say also kills human cells and may cause miscarriages, abnormal fetal development and low birth weight babies.

Environmental Health News reports today that one of the inert ingredients in Roundup, the country’s most widely used herbicide, might not be so innocuous after all. The story goes on to say:

The new findings intensify a debate about so-called “inerts” — the solvents, preservatives, surfactants and other substances that manufacturers add to pesticides. Nearly 4,000 inert ingredients are approved for use by the U.S. Environmental Protection Agency.

Roundup has been used for decades It’s active ingredient, glyphosate, has been subjected to studies and found safe. But, molecular biologist Gilles-Eric Seralini and his team of scientists at France’s University of Caen, decided to turn their microscopes on various ingredients in Roundup and see how they interact. Their conclusion: the inert ones increased the toxic effect Roundup has on human cells. The biggest culprit is polyethoxylated tallowamine, or POEA, found “more deadly to human embryonic, placental and umbilical cord cells than the herbicide itself – a finding the researchers call ‘astonishing,’” Environmental Health News reported.

Roundup’s manufacturer, Monsanto Co., and the EPA dismissed the concerns as unfounded. But controversies over so-called inert ingredients have erupted in Argentina, Croatia and Japan, the story says.  And, more than 250 environmental, health and labor organizations have asked the EPA to make changes to how inert ingredients in pesticides are identified.

Monsanto is already having a difficult year. Last month, it warned that profits are sagging due to increased competition from Chinese Roundup knockoffs, which are also applied to commercial crops. The company said there is now a worldwide glut of weed killer – a scary prospect in light of today’s news.

Luckily there are lots of chemical-free lawn care options.

Vinegar, an old standby for a variety of household chores, is also said to be a potent herbicide. Then there’s corn gluten. I’m not sure what corn gluten is exactly, but it’s supposed to be a weed killer extraordinaire.

Or you can just plant wildflowers, native grasses and clover. Greenies say native plants require less water and attention. Clover, meanwhile, fixes nitrogen in the soil, which makes it a natural fertilizer for other plants.