Protective clothing studies

Based on the patch method to assess worker or re-entry exposure, researchers have developed a database, which may be used to estimate exposure. Each patch from an individual in a study can be entered into the database separately, the residue data from patches from various body areas can be summed to yield a whole-body exposure number, and the data may be sorted as to worker tasks, equipment used, protective clothing worn, formulation types and other parameters. This is the basis for the currently used Pesticide Handlers Data Base (PHED), which was developed through a joint effort in the 1980s of CropLife America [formerly known as American Crop Protection Association (ACPA) and National Agricultural Chemicals Association (NACA)], the Environmental Protection Agency (ERA) and Health Canada. " The PHED is discussed in detail in another article in this book. 

Determination of the efficiency for pesticide exposure reduction with protective clothing a field study using biological monitoring... 

In addition, the use of biological monitoring has the advantage that skin penetration under particular conditions of protective clothing is included as well in the approach. The results of a dose-excretion study of propoxur by Meuling et al. (1991) using volunteers indicate a significant increase of the dermal uptake of the compound under conditions of occlusion, where there is increased blood flow, skin temperature, and skin moisture. 

In this part of the study, the internal dose of propoxur was assessed for HV applicators (n = 9) and harvesters (n = 18) using biological monitoring in two trials. In the first trial, workers wore their normal work clothing, followed by a trial where the same workers wore additional protective clothing. The minimum period between the two trials was 5 days. 

The relation between the calculated amount of IPP excreted in urine resulting from dermal exposure and actual exposure of the hands was studied for both work clothing and protective clothing trials using the regression model ... 

The design of a study by Davies et al. (1982) for mixers and applicators was similar to that of Nigg and Stamper (1983). "Between-days" variances of exposure were not given. Mean urinary metabolite concentrations were used to show reduction of internal exposure by protective clothing. The design of the study by van Rooij et al. (1993) was similar to our study (i.e., "within-worker" comparisons of internal exposure). Because no potential dermal exposure was assessed in this study, "within-worker" variances of potential exposure are not known. 

Mild skin irritation has been reported by workers at a munitions factory who were exposed to low levels of hexachloroethane. The workers were wearing protective clothing that greatly reduced exposure. No other information is available concerning health effects in people exposed to hexachloroethane. However, results of animal studies can be used to show how it can affect your health. Based on the animal data, hexachloroethane in the air can irritate your nose and lungs and cause some buildup of mucus in your nose, much like an allergy. It can also irritate your eyes and make them... 

Hexachloroethane has been found in the plasma of workers wearing protective clothing and respiratory protection suggesting that hexachloroethane can be absorbed following inhalation and/or dermal exposure. Based on the minimal effects seen on target tissues (liver and kidney) in animal studies, absorption from the lungs seems to be limited. Dermal absorption was also estimated to be low based on calculated dermal penetration rates. 

The 2,4-D study was similar to the 2,4,5-T study which included analyses of air, patches and total urine. In this study three helicopter crews were monitored during their routine forest spray operations in Washington and Oregon. An additional objective in this study was to compare exposure from the routine operation (Tj) with that received when workers wore protective clothing and followed added precautions designed to limit exposure (T2). The Ti and T2 operations were conducted with the same individuals in each crew with a 1-week interval between spray operations. Each crew included a pilot, a batchman, a mechanic, a supervisor, and two observers. The observers were located from 67 to 168 m away from the spray operator. Their role was to represent persons who might be in the area, but who were not directly associated with the spray operation. Protective... 

The absorbed dose measured in this study, as shown by the urine analyses, were too low and the replications too limited to allow accurate statistical comparisons for each worker duty. However, the total dose absorbed by workers in Tj was nearly double that of workers wearing the protective clothing in T2. 

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