Inner dermal exposure

Both inner and outer whole-body dosimeters are common tools to measure successfully dermal exposure to pesticide workers and are employed in a variety of ways in mixer-loader/applicator or re-entry studies. 

In order to determine the dermal exposure of volunteers to chlorpyrifos, the penetration of chlorpyrifos through the outer whole-body dosimeter (coveralls) to the inner body dosimeter (t-shirt and briefs) was measured. The penetration factor was calculated for each volunteer in the study from the experimental data by dividing the amount of chlorpyrifos on the t-shirt and brief sample by the amount of chlorpyrifos on the torso section of the coveralls. This method of calculation assumes that the surface area of the torso section of the coveralls is nearly the same as the surface area of the t-shirt and briefs worn directly under the torso section of the coveralls. A mean penetration factor for each worker type was calculated by averaging all the worker volunteer... 

These compounds would also be irritating to human skin. In contrast, dermal exposure to zinc oxide did not usually cause skin irritation to humans and animals. However, a few workers who routinely became covered with zinc oxide dust have had pustules on the axilla and inner thighs possibly formed in response to plugging of glands by sweat, bacteria, and zinc oxide dust. 

Front and back body pads as well as ankle pads generally showed only traces or low levels of diazinon. Body pads with the greatest amount of exposure contamination were those on the wrist and on the inner thigh just below the scrotal area. Table 11 includes a list of wrist dermal exposure. 

Among the first dermal dosimeters used in exposure research were 4 x 4-in cellulose or gauze patches which were pinned to the outer and inner surfaces of clothing or vests which farm workers would wear during the application or re-entry phase of the smdy. These patches were easy to manufacture and when pinned to the shirt or pants of the worker made for an easily used dosimeter pad. The major advantage to the use of the patch to estimate worker exposure was this method s ability to differentiate the relative contributions of pesticide residues to different parts of the worker s body. This sampling technique in turn could lead to recommendations (i.e., the use of... 

Muscle tremors and convulsions are characteristic effects of acute dermal phenol toxicity in laboratory animals. Tremors that developed into convulsions and prostration were reported in rats exposed to 107.1 mg/kg liquid phenol application surface areas were not reported (Conning and Hayes 1970). In pigs, application of 500 mg/kg over 35-40% of the body surface (0.44 mg/cm2/kg) resulted in muscular tremors in the head region within 3-5 minutes of exposure (Pullin et al. 1978). This was followed by dilation of the pupils, loss of coordination, and excess salivation and nasal discharge within 5 minutes of exposure. It was followed by convulsions, coma, and death 5-7 minutes after exposure in two of three pigs. Direct application of a dose of 37.5 mg/kg phenol to the inner ear resulted in a reduced threshold for auditory brainstem response (Schmidt et al. 1990). 

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