Lawn Care Chemical’s Deadly Secret

Report: A labeling loophole means the world’s most common herbicide is even more toxic than originally believed.

July 7, 2009

Maybe coating your lawn with poison isn't such a good idea.

RODALE NEWS, EMMAUS, PA—If you ever turn over a bottle of Roundup, one of the most popular chemical weed killers in the world, you’ll see glyphosate listed as the active ingredient. What you won’t see is a list of inactive ingredients. And that’s problematic. Because researchers who recently tested the product’s active ingredient in combination with certain inert ones found the combo makes this weed killer much more toxic than previously disclosed. “It’s not as benign as people are led to believe,” says Greg Bowman, editor of the Rodale Institute’s New Farm online publication, which focuses on nontoxic farming methods. And even the listed ingredient may be more dangerous than was previously thought. “More and more studies by medical and agricultural specialists are revealing the subtle, low-level impact that Roundup’s main ingredient, glyphosate, has on wildlife, soil life, and—directly and indirectly—people themselves,” Bowman says.


THE DETAILS: Researchers tested four combinations of Roundup on cultured human cells, and found that one inert ingredient in particular, polyethoxylated tallowamine, or POEA, significantly boosted the toxic effects of the main ingredient, glyphosate. In the study, the combination of the two killed or damaged many more of the cells than glyphosate alone. The study was published in the journal Chemical Research in Toxicology.

WHAT IT MEANS: In the U.S. alone, farmers and homeowners use an estimated 100 million pounds of the Roundup herbicide a year. The problem is, weeds are becoming resistant to the chemical, so farmers are forced to apply more and more of it. Between 1994 and 2005, the use of glyphosate increased 1,500 percent. And while the manufacturer and the U.S. Environmental Protection Agency say the product is safe, a growing body of nonindustry-funded scientific research suggests otherwise. When the active ingredient alone is tested—which is standard procedure in toxicology testing—the product may seem relatively safe. But when all the chemicals in the product are tested together, which provides a realistic snapshot of the product’s safety, the results suggest much more toxicity.

A recent Rodale Institute article on pesticides like Roundup highlighted some of the research showing the detrimental effects this type of weed killer has on people and amphibians:

• In May 2009, a group of environmental lawyers in Argentina filed a petition to ban glyphosate after a study linked it to embryonic mutations affecting the nervous system and skeletal development in amphibians.

• Government-funded research out of Argentina also found higher-than-normal rates of birth defects and cancer rates in people in areas with glyphosate fumigation.

• In 2005, a study published in Environmental Health Perspectives found Roundup to be toxic to placental cells at concentrations lower than that used in agriculture.

You don’t need nasty chemicals to keep your lawn and garden looking gorgeous—try these techniques and keep dangerous chemicals away.

• Go natural and save money. Protect your family and the environment (and save money in the process) by using tried and true organic techniques from Hint: Corn meal gluten could be your new secret weapon.

• Get off the Roundup treadmill. A product that becomes less and less effective, forcing consumers to buy more and more of it, may be profitable for the manufacturers. But it’s not so great for your budget. The nonprofit Rodale Institute, a pioneer organization in organic farming, recently investigated the topic of superweeds, ones that have grown resistant to glyphosate-based herbicides like Roundup. The U.S. Department of Agriculture–named “worst weed in the world,” Johnsongrass, is among them. Switch to chemical-free methods for a better bargain.