Occupational exposure during application and removal of antifouling paints.

Exposure data on biocides are relatively rare in published literature, especially for secondary exposure. This is also the case for antifouling exposure. Therefore, a field study was carried out measuring exposure to antifouling paints. Both primary exposure (rolling and spraying) and secondary exposure (during sand blasting) were studied. Exposure during rolling was measured in boatyards where paints containing dichlofluanid (DCF) were applied. Spraying was measured in dockyards (larger than boatyards) where paints containing copper were applied. Furthermore, during sand blasting the removal of old paint layers containing copper was measured. A total of 54 datasets was collected, both for inhalation and dermal exposure data. For paint and stripped paint bulk analyses were performed. The following values are all arithmetic means of the datasets. Inhalation of copper amounted to 3 mg m-3 during spraying and to 0.8 mg m-3 during sand blasting. Potential body exposure loading amounted to 272 mg h-1 copper during spraying and 33 mg h-1 during sand blasting. For dichlofluanid the inhalation exposure loading was 0.14 mg m-3 during rolling, whereas the potential body exposure loading was 267 mg h-1 and potential hand exposure loading 277 mg h-1. The results for primary exposure compare well to the very few public data available. For the secondary exposure (sand blasting) no comparable data were available. The present study shows that the exposure loading should be considered more extensively, including applicable protective gear. In this light the findings for the potmen during sand blasting suggest that personal protective equipment should be (re)considered carefully.

Size selective dustiness and exposure; simulated workplace comparisons.

A simulated workplace study was conducted to investigate the relation between inhalation exposure and dustiness determined with a rotating drum dustiness tester. Three powders were used in the study, i.e. magnesium stearate, representing a very dusty powder, and aluminium oxide and calcium carbonate, representing low and very low dusty powders, respectively. Two scenarios of handling small volume of powders were included; sweeping/cleaning and scooping/weighing/adding. Size-selective dust exposure was assessed using MultiDust (dual-fraction) IOM and RespiCon sampling heads. For the present operation scenarios, dustiness showed itself to be the major determinant of exposure and explained approximately 70% of the exposure variances. The ratios of respirable and inhalable fractions as determined by dustiness tests were comparable with the ratios observed for exposure. The results emphasize the relevance of dustiness as a parameter to characterize substances according to potential for exposure.

Effectiveness of personal protective equipment: relevance of dermal and inhalation exposure to chlorpyrifos among pest control operators.

This study assessed the effectiveness of a custom fit personal protective equipment (PPE) program aimed at reducing occupational exposure to pesticides. The intervention study was carried out on 15 pest control operators (PCOs) during mixing/loading and application of chlorpyrifos. Each worker was measured twice; first while the worker used PPE as normal (baseline measurement), and second after making some adjustments to the PPE (postintervention measurement). The applied intervention consisted of a tight-fitting, full-face respirator, fit-testing, long gloves, chemical-proof boots, a Tyvek hood, and an instruction video that was shown prior to putting on the PPE. A comprehensive evaluation program was used for the within-subject comparisons, including assessment of potential dermal exposure, actual dermal exposure, inhalation exposure, and internal dose as measured by the urinary metabolite 3,5,6-trichloro-2-pyridinol (TCP). The PPE program resulted in a significant increase in fit factors from a mean of 670 to 132,000. Actual dermal exposure levels decreased on average by fourfold after implementation of the PPE program (baseline AM = 132.1 microg; postintervention AM = 32.6 microg). The TCP levels in urine collected 24-32 hours after spray activities were lower in the postintervention data set (AM = 21.2 microg TCP/g creatinine vs. AM = 13.9 microg TCP/g creatinine). However, it is impossible to attribute these differences totally to the PPE program since workers had significant and varying urinary TCP levels before onset of spraying activities. Linear regression models showed that dermal exposure was only a predictive parameter for TCP levels in urine in the baseline data set. Although the results should be interpreted cautiously this study suggests a protective effect of the evaluated PPE program.