Protection afforded greenhouse pesticide applicators by coveralls: a field test.

Applicators of chlorpyrifos, fluvalinate, and ethazol to ornamentals in a Florida greenhouse were monitored for exposure in a replicated experiment. Pesticide exposure was assessed, using pads placed inside and outside three types of protective coveralls. Potential total body accumulation rates, excluding hands, as calculated from outside pads, depended strongly upon the rate at which pesticide left the spray nozzles. When these total body rates were normalized for spray rate, the mean results, in mg-deposited/kg-sprayed, ranged from 166 to 1126, depending upon the compound applied and the application device. Overall penetration of pesticide through a disposable synthetic coverall was 3 +/- 1% for chlorpyrifos and fluvalinate, and 35 +/- 9% for ethazol. Penetration through a reusable treated twill coverall was 19 +/- 6% for chlorpyrifos, 22 +/- 13% for fluvalinate, and 38 +/- 5% for ethazol.

Field evaluation of coverall fabrics: heat stress and pesticide penetration.

The effect of wearing coveralls on the heat stress of ten professional airblast applicators of ethion to Florida citrus were studied. During the period June 21, 1988 to August 9, 1988, applicators wore protective clothing of the same design, but made of seven different fabrics. Heat stress was evaluated by measuring the mean skin temperature, oral temperature, and heart rate of pesticide applicators. Subjects also provided subjective evaluations. Seven environmental variables were also monitored. Although each fabric was replicated an average of 17 times for thermal comfort and an average of 23 times for penetration, statistical tests for differences among fabrics were usually not significant at the p less than 0.05 level. Observed differences among suits were statistically significant at p = 0.27 for the heat stress experiment, and extended over the range p = 0.003-0.500 for the penetration experiment. Lighter weight, untreated fabrics marginally ameliorated heat stress under severe environmental conditions, but they allowed more pesticide penetration.

Protection afforded citrus pesticide applicators by coveralls.

Four airblast applicators of the pesticides dicofol and ethion to Florida citrus were monitored for pesticide exposure with pads placed inside and outside two types of protective coveralls. Hand exposure was not assessed. Pesticide accumulated uniformly over the coveralls' outer surface at a mean rate of 55 ±6 mg/hr. The penetration of ethion through a reusable treated twill suit was 8 ±2% and through a disposable synthetic suit was 6 ±4%; corresponding values for dicofol were 4 ±1% and 1 ±0%, respectively. While these four penetration values could not be separated statistically at p<0.05, it isprobable (p<0.20) that ethion was the better penetrator, and the disposable synthetic suit the better protector against dicofol.

Pesticide exposure to greenhouse handgunners.

The exposure of pesticide applicators in a commercial greenhouse facility was assessed. Data were collected from four handgunners who applied fluvalinate (insecticide), chlorpyrifos (insecticide), ethazol (fungicide), and dicofol (miticide). Potential exposure was measured with exposure pads placed outside all clothing of the applicator. Handwashes and air samples were also collected, as were pre- and post-exposure tank mixture samples. Pesticide penetration was measured with exposure pads placed inside protective clothing. When all exposure assessments were normalized for spray rate, it was determined that applicators were at significantly greater potential dermal risk (excluding hands) from fluvalinate. The normalized air samples showed significantly more exposure to the applicator from ethazol. Exposure to outside pads was primarily (84%) to the legs of the applicators. Ethazol penetrated Tyvek coveralls more readily than the other compounds. Tank mixture analyses suggested that the wettable powder formulations were not well-mixed.

The development and use of a universal model to predict tree crop harvester pesticide exposure.

A simple regression model is presented for predicting the transfer of residual foliar applied pesticide to the body of a Florida citrus harvester. This model is dependent on work rate and residue concentration and agrees with an earlier model derived from similar data taken from a California study. This suggests that observed regional differences in the morbidity of harvesters in treated fields may be due to regional differences in foliar pesticide residue levels rather than regional differences in transport mechanisms of pesticide from foliage to worker. Eventual metabolite output in worker urine is also predicted.