Plant City has once again entered strawberry growing season, and families will soon join in the area’s long history of picking berries together and attending the Florida Strawberry Festival.
In 2013 and this year, a new product has helped growers produce those sweet berries: a soil fumigant called Paladin.
Paladin is used to suppress weeds, soil-borne pathogens and nematodes (parasitic roundworms). Before plants are put into the ground, Paladin is injected into the soil. Tarps cover the ground to contain the chemical, and are removed 12 days later.
The active ingredient in Paladin is dimethyl disulfide, which is a replacement for methyl bromide. Methyl bromide was used widely as an effective fumigant, until the EPA banned it in 2005 because it had been depleting the ozone layer and polluting the air.
“Sometimes, you have to use common sense, and it was not a good common-sense decision to eliminate the use of methyl bromide,” said Kenneth Parker, executive director of the Florida Strawberry Growers Association.
But, he said, Paladin was one of many effective fumigants that had come to the market as a replacement.
Many Plant City-area growers began using Paladin in 2013, and they have applied it again this year.
ODOR AND HEALTH
Because of its sulfur content, Paladin has an odor that has been compared to garlic or rotting cabbage. Last year, growers in the area received numerous complaints from neighbors, who said the smell was unpleasant and overwhelming. This year, Arkema, the chemical company that produces Paladin, came up with a solution to the odor.
“We wanted to make a change to make some differences for people living closer to the fields,” said Rob Welker, a product steward for Arkema.
Arkema dictated the use of an improved tarp, which contains the odor more effectively than last year’s tarps. The new tarp is made of Totally Impermeable Film.
“TIF has done a fantastic job of capturing and not releasing any of the odor from the fumigation process,” Parker said. “(Arkema) has taken great strides to limit the smell.”
Andy McDonald is the farm manager for Sweet Life Farms, a Plant City strawberry growing operation that has used Paladin in its fields last year and this year.
McDonald said Paladin was safer and more effective than other replacements for methyl bromide. He lives within 100 yards of a 70-acre field, where he applied the fumigant this year.
“I wouldn’t put it out here this close to my house, this close to my family, if I had any concerns about it,” he said.
Paladin is a restricted-use pesticide, because the EPA expects inhalation exposure at high levels to cause human health problems. However, Arkema includes strict, detailed protocol on Paladin’s label that prevents inhalation exposure if followed correctly. It also includes requirements for a buffer zone, to protect people who live or work close to the fields where Paladin is applied.
Local media reported both years that a Dover family had become ill during pre-planting season, and they believed that their exposure to Paladin used in fields near their home had caused the sickness. McDonald said he wasn’t sure the family’s theory was accurate.
“Arkema has been really good at going around and doing all these air measurements, and they found none over there,” McDonald said.
The Florida Department of Agriculture reported the smell itself made some sensitive people feel nauseated last year, but their symptoms were not due to direct exposure.
Although the strict guidelines for application of Paladin intend to prevent it from escaping the agricultural areas where it is applied, as with any chemical product, there is the potential for contamination to occur. The chemical could leak from a broken container before it is applied, for example, or even after it is applied, excessive stormwater could carry it into the outside environment.
The New York State Department of Environmental Conservation conducted a study in 2012 and found that Paladin was moderately toxic to mammals, slightly toxic to birds and moderately to highly toxic for aquatic species. This kind of report is produced by individual state departments if they determine a need. The Florida Department of Environmental Protection has not yet studied Paladin’s effect on local wildlife.
Joe Barron is the environmental manager of water for the Hillsborough County Environmental Protection Commission. Barron said it was also unclear what effect dimethyl disulfide would have had if it were to end up in the watershed.
“Organic analysis is generally quite expensive, and our budgets generally don’t allow for it, unless it’s required by permit,” Barron said.
There are five Hillsborough County EPC water monitoring stations in the Plant City area, but none has been tested for dimethyl disulfide.
Contact Catherine Sinclair at firstname.lastname@example.org.