Chemically Speaking - September 2006
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Decisions Issued for Lindane, PCNB, Arsenicals, Triadimefon, and Carbofuran
The final push towards reregistration that was due in August 2006 has produced some interesting outcomes. Lindane, which has only been used recently as a seed treatment, is no longer allowed to be used in any pesticide products. Once all of the registrants of technical and end use products request 
cancellation, tolerances for lindane will be revoked.
The fungicide PCNB (approximately 3,000 pounds used in Florida in 2005) will not be eligible for registration on turf, residential ornamentals, cole crops (unless for clubroot), green bean, cotton, potato, dry beans and peas, garlic, peanut, tomato, pepper, and ornamentals in commercial production (except for flowering bulbs). Those uses eligible for registration are cole crops (clubroot only), ornamental bulbs for commercial production and seed treatment.
Based on the Agency’s concern that organic arsenical herbicides will transform to a more toxic inorganic form of arsenic in the soil, with subsequent transfer to drinking water, the herbicides MSMA, DSMA, CAMA, and cacodylic acid are ineligible for reregistration. Consequently, all uses (approximately 6,000 pounds of MSMA used in Florida in 2005) will be canceled. The task force for these products believes that the Agency has overestimated exposure by adding inorganic arsenic to the risk assessment, underestimated the benefits to agriculture and turf management, and will “vigorously defend its member company products.”
The popular residential lawn fungicide triadimefon will also be voluntarily cancelled for this site. Tolerances that are associated with this fungicide (apple, grape, pear, pineapple and raspberry) are proposed for revocation, except for pineapple.
As for the pesticide carbofuran (approximately 16,000 pounds used in Florida in 2005), the EPA stated in early August that all uses will be canceled immediately except for corn, pepper, artichoke and sunflower, which will be phased out by 2010. The registrant, FMC Corporation, disputes the Agency’s evaluation of carbofuran and the decision to cancel all uses of the chemical, and would not voluntarily cancel registration while examining legal options. (Federal Register, 8/2/06, 8/9/06 & 8/30/06, Pesticide & Toxic Chemical News, 8/7/06, Chemical Regulation Reporter, 8/21/06).
