8292373 Chimney sweeps exposure to soot measured as black carbon with repeated sampling

<h3>Objective</h3> Accurate assessment of occupational exposure is of importance for epidemiological studies. Two factors affecting the accuracy are the number of measurements and their quality, which determines how much information the collected data can provide. One way to address both these factors is by using self-monitoring methods with a repeated sampling strategy. This strategy was used in the present study where the aim was to assess the exposure to soot among chimney sweeps, an occupation at high risk of many severe health outcomes related to their exposure to soot. <h3>Material and Methods</h3> Exposure to soot was measured as black carbon. To assess the variation throughout a workday real-time monitoring instruments were used, micro-aethalometers (microAeth® model MA200 and AE51, AethLabs USA). Personal sampling (1-min average) was complemented with a diary specifying work task and duration. Personal samplings were performed for eight consecutive workdays for each of the 20 participants. The measurements were administrated by the sweeps themselves, except for the first sampling day when a trained occupational hygienist administrated and demonstrated the sampling procedure to each participant. <h3>Results</h3> The mean exposure to black carbon for the group was 13.6 µg/m3, with a wide range (1.1-48.9 µg/m3) among the 20 participants. Daily mean exposures varied considerably (up to 49-fold) between the eight sampling days for an individual chimney sweep. <h3>Conclusion</h3> We found a large variability in daily mean exposure to soot between the individual workers as well as between different days for an individual worker. The large within-worker variability suggests that repeated samplings on different days should be performed, to accurately assess the occupational exposure. Furthermore, we intend to evaluate how various determinants, such as different fuels, may affect the exposure to soot among chimney sweeps. <h3>Funding</h3> Funding for this project was provided by AFA Insurance and the MSB Swedish Civil Contingencies Agency.