MSMA lives . . . for now
24 Jul, 2008 By: Larry Aylward Athletic Turf NewsGolf turf expert Fred Yelverton, a professor of crop science at North Carolina State University, is saying the same thing. Yelverton, who spoke at the Warm-Season Weed Control Symposium sponsored by Bayer Environmental Science July 9-10 in Newport, R.I., reported that the Environmental Protection Agency might not ban MSMA after all.
MSMA, classified as an organic arsenical, is used for grass weed control in bermudagrass and zoysiagrass and on some cool-season turfgrasses. It is used for postemergence control of goosegrass, crabgrasses and dallisgrass in bermudagrass.
 North Carolina State's Fred Yelverton and other top industry researchers discussed turf science at the Warm-Season Weed Control Symposium. |
In 2006, EPA announced it would cancel reregistration of any pesticides containing MSMA. Arsenic levels left by MSMA "raise a concern for cancer risk," EPA officials concluded.
But nearly two years later, MSMA is still around.
"We thought EPA was going to ban it six months ago," Yelverton says, "but it has new life. What are the chances of keeping it? I would say 50-50. The final decision could be tomorrow, or it might be six months from now."
EPA is taking a second look at MSMA because the organization admits it acted too quickly to dismiss it.
"There are some people who believe the EPA was under political pressure to ban some products," Yelverton says. "Because MSMA was not used in many commodities, it was an easy target."
The EPA has agreed to take a second look at MSMA for two reasons, Yelverton says. First, it underestimated the need for MSMA, especially in the golf course industry. Second, EPA admits it might have overestimated the risk of organic arsenic and MSMA's contribution to environmental inorganic arsenic levels. Yelverton points out that organic arsenic is a naturally occurring element.
"You can find it anywhere," he says. "We're all exposed to it every day. It is added to chicken feed, for example. So when you eat chicken, you're exposed to it."
The problem is that people, including environmentalists, associate MSMA with inorganic arsenics, which are very toxic. "But organic arsenics are not," he adds.
Yelverton says there's a conversion rate between organic arsenicals to inorganic arsenic, but it is very low. He says the EPA has now realized this.
Yelverton points out that research shows MSMA has low mobility and strongly absorbs into soil.
"It doesn't leech into the ground water," he says. "From an environmental standpoint, it's safe."
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