Personal exposure of workers to atmospheric PAHs on gasworks sites--The SOLEX study

The aim of the SOLEX study was to estimate the personal exposure of workers to atmospheric polycyclic aromatic hydrocarbons (PAHs) on former gasworks sites in the Paris metropolitan area. Devices to sample gas and particulate phases for 9 PAHs were carried during one working day of a study week in November 1997 by 24 workers and in June 1998 by 19 workers with contrasted job profiles involving different opportunities for contact with the soil; among these volunteers, some were active in the process of contaminated soil remediation during the November study period. PAH concentrations were measured by high-performance liquid chromatography. Subjects working on the site under remediation were clearly more exposed (684.1 ng/m3 for total PAHs in November 1997) than workers, without close contact with soil, whose PAH exposure was similar to that measured by fixed monitors in the ambient air in Paris. The contrasts were weaker in June 1998, when soil remediation had nearly been completed. Only subjects involved in activities with close contact with the ground were found with exposures exceeding background levels. Further investigations are needed to improve our understanding of the influence of the pollutants present in the soil.

Feasibility of assessing dermal exposure to PAHs of workers on gaswork sites--the SOLEX study

Population exposure to pollutants in soil is an important public health concern. Difficult to measure, it is usually estimated using multimedia models. Modeling data predict that the skin surface is a predominant exposure route in roughly 15% of the US Superfund sites. Nonetheless, no study has confirmed these predictions. The SOLEX study was an opportunity to study the feasibility of estimating the cutaneous polycyclic aromatic hydrocarbons (PAHs: all 16 of the United States Environmental Protection Agency list) load of workers at three former manufactured gas sites, one of those being under remediation. Over two measurement periods (November 1997 and June 1998), 30 and 28 volunteers, respectively, were equipped for a single day work with five pads that collected soil particles and were placed at the neck, shoulder, wrist, groin, and ankle. Pad contamination was observed for six of the nine workers on the site being remediated but not on other sites. The wrist pad was most often affected, followed by the neck pad, these are, the exposed regions of the body. The PAHs most frequently identified were anthracene, fluoranthene, naphthalene, phenanthrene, and pyrene, at concentrations relatively high. In conclusion, this study showed that estimating skin exposure to soil pollutants is feasible. Secondly, it suggested that only subjects in close contact with the soil had a detectable exposure to PAHs. Extension of this approach to other exposure settings is warranted, especially among children playing in polluted public or private gardens, because their games lead to frequent contact with the soil.

The relationship between polycyclic aromatic hydrocarbons in air and in urine of workers in a Söderberg potroom

The relationships between increase of urinary 1-hydroxypyrene over the workweek and the airborne concentrations of benzo(a)pyrene and coal tar pitch volatiles (CTPVs) were studied among groups of workers in a vertical-stud Söderberg potroom of an aluminum smelter. There was a strong correlation between the natural logarithm of the pyrene concentration and the natural logarithm of the total polycyclic aromatic hydrocarbon (PAHs) concentration in personal air samples (r = 0.94). 1-Hydroxypyrene as the major metabolite of pyrene, a polycyclic aromatic hydrocarbon, was used as a marker for exposure to PAHs. A strong positive correlation was found between the natural logarithm of increase of urinary 1-hydroxypyrene and the natural logarithm of the estimated airborne PAH exposure (R2 = 0.84 with CTPV) when the use of facial protective clothing was taken into account. The relationship between increase of urinary 1-hydroxypyrene and PAHs differed for workers who used facial protective clothing under their respirators compared to those who did not. A contradictory fact was found: the use of facial protection seemed to lead to an elevated increase of 1-hydroxypyrene over the workweek. The regression model for the relationship between increase of urinary 1-hydroxypyrene over the workweek and airborne CTPV was: LN(change in 1-hydroxypyrene) = -4.7 + 1.2 LN(CTPV) -0.44 LN(CTPV)*(use of facial protection) + 3.5 (use of facial protection).