Comparison of Measurement Methods for Dermal Exposure to Hazardous Chemicals at the Workplace: The SysDEA Project.

There is a principal need for more precise methodology with regard to the determination of occupational dermal exposure. The goal of the Systematic analysis of Dermal Exposure to hazardous chemical Agents at the workplace project was therefore to generate scientific knowledge to improve and standardize measurement methods for dermal exposure to chemicals at the workplace. In addition, the comparability of different measurement methods was investigated. Different methods (body sampling by means of coveralls and patches, hand sampling by means of gloves and washing, and head sampling by means of headbands and wiping) were compared. Volunteers repeatedly performed a selection of tasks under standardized conditions in test chambers to increase the reproducibility and decrease variability. The selected tasks were pouring, rolling, spraying, and handling of objects immersed in liquid formulations, as well as dumping and handling objects contaminated with powder. For the chemical analysis, the surrogate test substance Tinopal SWN was analyzed by means of a high-performance liquid chromatographic method using a fluorescence detector. Tinopal SWN was either applied as a solid product in its pure form, or as a low and high viscosity liquid containing Tinopal SWN in dissolved form. To compare the sampling methods with patches and coveralls, the exposure values as measured on the patches were extrapolated to the surface areas of the respective parts of the coverall. Based on this extrapolation approach, using the patch method resulted in somewhat higher exposure values compared to using a coverall for all exposure situations, but the differences were only statistically significant in case of the liquid exposure situations. Using gloves resulted in significantly higher exposure values compared to hand wash for handling immersed objects, rolling, and handling contaminated objects, and slightly higher (not significant) exposure values during pouring and spraying. In the same context, applying wipe sampling resulted in higher exposure values than using a headband, which was at least partly due to extrapolation of the wipe results to the surface area of the headband. No 'golden standard' with regard to a preferred measurement method for dermal exposure could be identified from the methods as investigated in the current study.

Dermal and Inhalation Exposure of Workers during Control of Oak Processionary Moth (OPM) by Spray Applications.

BACKGROUND: The caterpillars of the oak processionary moth (OPM) form stinging hairs, which release an irritant poison. They cause skin and eye irritation and sometimes even breathing difficulties and allergic reactions. OPM is mainly controlled by spraying insecticides. Insecticides applied for protection of human health must be authorized under the Biocidal Products Regulation (BPR) (EU) No 528/2012. In order to assess safety of professional use, which is a key requirement for the authorization, a risk assessment based on exposure estimation has to be performed. However, no exposure data specific for OPM control was available until now. Existing models for agricultural spray applications such as Agricultural Operator Exposure Model cover different spray patterns and equipment and were therefore considered too unreliable for assessment of OPM control. METHODS: We have studied dermal and inhalation exposure of certified pest control operators resulting from spraying DimilinTM 80 WG suspensions with vehicle-mounted spraying (VMS) and with handheld spraying (HHS) devices for control of OPM. Exposure resulting from these applications, from weighing and portioning of the granular product and from cleaning of contaminated spraying devices was studied. Dermal exposure was investigated by whole body dosimetry using disposable chemical protective coveralls and cotton gloves as samplers. Inhalation exposure was measured using personal air samplers. The active substance diflubenzuron was quantified by gas chromatography-mass spectrometry with positive chemical ionization and by high-performance liquid chromatography for dermal and inhalation measurements, respectively. RESULTS: The exposure was dominated by the dermal pathway. HHS results in considerably higher operator exposure than VMS. Comparison with data from typical agricultural spraying applications revealed that OPM control results in much higher exposure of operators for both, vehicle-mounted and handheld equipment. CONCLUSIONS: Comprehensive data on potential dermal and inhalation exposure is presented in this article, along with typical figures for handled and applied amounts of product and respective task durations. This data is suitable for risk assessments in regulatory frameworks such as the European BPR.