|Spraying paraquat at a plantation near Kuala Lumpur,|
Malaysia. Pesticides that are prohibited in Europe are
exported for sale elsewhere in the world.
Credit: Zainal Abd Halim/Reuters
by Danny Hakim, The New York Times,
20 December 2016
Paraquat, one of many pesticides that can’t be used in Europe
but is sold in the United States and elsewhere, has been
linked to Parkinson’s disease in a growing body of research.
HUDDERSFIELD, England — The factory here, set amid a brick campus in a green and hilly industrial town, recently celebrated its centennial.
It produces paraquat, one of the world’s most enduring weed killers — but not one that can be purchased in this part of northern England, in the rest of Britain or across the Channel in the rest of the European Union.
So it will be sent to the United States, or another part of the globe that still allows paraquat to be sprayed on weeds.
Paraquat has long been controversial because of its use in suicides in many parts of the world, since drinking one sip can be lethal. But now regulators in the United States are grappling with a wave of research linking paraquat to a less immediately apparent effect — Parkinson’s disease.
In a recent, little noticed regulatory filing, the Environmental Protection Agency said, “There is a large body of epidemiology data on paraquat dichloride use and Parkinson’s disease.” The agency is weighing whether to continue allowing the chemical to be sprayed on American cropland, although a decision is not expected until 2018, and it is unclear how the incoming administration of Donald J. Trump will view the matter.
In the meantime, many of the nations that ban paraquat and other chemicals whose use is contentious still allow them to be manufactured as long as they are exported to faraway fields. The Huddersfield plant is owned by Syngenta, the pesticide giant based in Switzerland, which has not allowed paraquat since 1989.
Even the government of China, a nation not known for environmental regulation, said in 2012 that it would phase out paraquat “to safeguard people’s lives.” But it still allows production for export.
As Europe and China move away from paraquat, its use is rebounding in the United States. That is particularly true for soybean fields, where the number of pounds used is up more than fourfold over the past decade, according to Department of Agriculture data.
The world’s most popular weed killer is Monsanto’s Roundup; some 220 million pounds of its active ingredient were used last year in the United States, according to the E.P.A. But weeds are becoming resistant to Roundup, and paraquat has been marketed as an alternative. Last year, seven million pounds of paraquat were used in the United States, on nearly 15 million acres, Syngenta said.
Paraquat is just one of scores of pesticides prohibited in Europe but sold outside it. In 2013, the European Union imposed a moratorium on a widely used group of insecticides made by Syngenta and Bayer, the German giant, that were linked to a decline in bee colonies. In 2003, the European Union banned one of the most popular weed killers in America, Syngenta’s atrazine.
Industry officials and academics funded by agrochemical companies often criticize Europe’s regulators for taking a precautionary approach to regulation. They frequently claim that the risks of these various chemicals are well understood. But paraquat shows how complex the question of risk can be.
While the possibility of a Parkinson’s link has been cited in studies going back more than two decades, research in the past five years has intensified, including a prominent study by the National Institutes of Health and meta-analyses of a large body of research. The studies have looked at the exposure of farmers and others who spray paraquat, as well as people who live near where it is used, which can include nonagricultural settings like those around roads and rail tracks.
“The data is overwhelming” linking paraquat and Parkinson’s disease, said Dr. Samuel M. Goldman, an epidemiologist in the San Francisco Veterans Affairs health system who has studied the connection. “I’m not a farmer, I don’t need to kill weeds, but I have to believe there are less dangerous options out there.”