U.S. EPA today proposed to start gradually banning a pesticide often used on cocoa beans and dried fruits that degrades to fluoride, a move closely linked to the Obama administration's decision last week to curb the maximum levels of fluoride in drinking water out of concern for children's health.
EPA's bid to wind down legal use of sulfuryl fluoride, citing the health risk to children posed by aggregate fluoride exposure, marks a long-awaited victory by the three public-health groups that first asked the agency to rein in the pesticide more than five years ago.
One of the three advocacy organizations, the Environmental Working Group (EWG), said the sulfuryl fluoride phaseout appears to be EPA's first official granting of any pesticide restriction petition filed by green advocates.
The Department of Health and Human Services and EPA announced Friday that fluoride, long considered a beneficial tap-water additive that helps prevent cavities, should be restricted to 0.7 milligrams per liter, or the low end of previous legal ranges (E&ENews PM, Jan. 7).
In its proposed prohibition on sulfuryl fluoride, EPA acknowledged that the pesticide's residues on food are "responsible for a tiny fraction of aggregate fluoride exposure" but deemed that children's total contact with fluoride in the environment -- through drinking water as well as toothpaste -- posed an excess risk of tooth and bone damage.
This week's twin fluoride restrictions reflect "a growing consensus that Americans are exposed to too much fluoride," EWG senior vice president for research, Jane Houlihan, said today. "It raises the concern that, for many decades now, the public has been overexposed."
First approved for use as an anti-termite insecticide more than 50 years ago, sulfuryl fluoride was federally registered for use on food in 2004 and 2005 by Dow AgroSciences LLC as an alternative to methyl bromide, a pesticide that began to be phased out of commerce after the 1987 Montreal Protocol identified it as a depleter of the ozone layer.
Soon after the chemical was approved as a food fumigant, the advocacy groups Fluoride Action Network (FAN) and Beyond Pesticides joined EWG in filing a formal objection with EPA. As in the case of Friday's fluoride announcement, today's sulfuryl fluoride limits came in the wake of a revised risk assessment the agency conducted after a 2006 National Academy of Sciences report urged it to consider dental fluorosis as a negative health consequence of exposure rather than a cosmetic impediment.
Dental fluorosis, which manifests as spotting on the teeth among children who consume too much fluoride as their mouths develop, can lead to long-term breakdown of the tooth enamel and other painful effects.
The gradual EPA removal of sulfuryl fluoride allowances will be subject to public comment before taking effect and include a three-year head start for significantly affected industries such as the cocoa and walnuts sectors.
Estimating that the pesticide is applied to 100 percent of cocoa crops, EPA warned in its proposed phaseout that "cocoa imports (which in 2009 were valued at approximately $1.2 billion) would be lost due to either destruction or refusal of shipments by warehouse operators" unless businesses can develop a viable alternative to sulfuryl fluoride for cocoa fumigation.
Today's EPA proposal also references multiple objections Dow had raised in previous years to arguments made by the advocacy groups behind the petition, suggesting that pushback from industry on the sulfuryl fluoride limits can be reasonably expected.
Click here to read a pre-publication copy of EPA's proposal to phase out sulfuryl fluoride tolerances.