Reduced “Golfer/Recreational” Exposure to Turfgrass Pesticides by
Management of Post-Application Irrigation and Application Rates.
Dr. John Clark, University of Massachusetts, 3 years, $13,000/year.
Objective(s): 1. Evaluate the optimal use of post-application irrigation at various
pesticide rates to minimize human exposure. 2. Project will create a database on where
and how much pesticide is actually absorbed during the play of golf/recreation on
turfgrass. 3. Once exposures are understood then effective means of reducing the
exposure can be developed.
Results: The project is part of an ongoing larger study being funded by the USDA
and USGA and will begin the Summer of 2000.
2000 Results: This ongoing study seeks the best management practices that reduce the potential for golfer exposure to volatile and dislodgeable foliar residues of turfgrass pesticides. Major routes of pesticide exposure for humans are primarily through inhalation and dermal penetration. Research has begun to evaluate the optimal use of post-application irrigation to minimize human exposure. Simulating 18-hole rounds of golf by researchers following application will be an exposure method. Samples of whole body dosimeters, hand rinses, face and neck wipes, personal air samplers, urine samples and blood samples, totaling 140 volatile and foliar dislodgeable samples have been collected and been evaluated. Preliminary results indicate that overall exposure and actual whole body uptake of chlorpyrifos is low. Chlorpyrifos is considered a high risk insecticide because of its high volatility and inherent high toxicity. Even with these characteristics, its potential for exposure that would result in human health implications after a round of golf is not likely. In addition, newer pesticides that do not share the same potentially harmful chemistry are expected to be even lower risks.
2001 Results: We have begun to evaluate the optimal use of post-application irrigation, reentry intervals, application of less toxic materials and application strategies that result in less than full coverage to minimize human exposure to turfgrass pesticides and environmental impact of their breakdown products. We have established that dermal exposure is the most significant route of pesticide uptake by golfers. Following Dursban (chlorpyrifos) application at full rate and coverage, however, Hazard Quotients (HQs), which are calculated from dislodgeable foliar residues, whole body dosimetry (residues on clothes, hands, face and personal air samplers) and whole body biomonitoring (estimation of absorbed dose using urinary metabolites) of individuals simulating the play of golf, indicate exposures that are deemed safe using the USEPA HQ criteria. When chlorpyrifos is applied to only tees and greens, the amount absorbed is reduced at least 80%. Application of Tempo (cyfluthrin, a pyrethroids insecticide of low toxicity) results in substantially reduced HQs, again indicating a safe exposure. Thus, a one-hour reentry interval following pesticide application with ¼-1/2 inch (0.65-1.3 cm) post-application irrigation and less than full coverage applications of less toxic pesticides are effective means to attenuate exposures and hazard to golfers.
