Microenvironmental exposure to mercury vapor

Abstract

Work area and breathing zone samples were collected in a factory utilizing metallic mercury and analyzed for mercury vapor content. Breathing zone samples averaged several fold higher in concentration than concurrent area samples, reflecting a "microenvironmental" exposure to mercury vapor, presumably from contaminated clothing and hands. Blood and corrected total urine mercury values correlated well with the average microenvironmental exposure level for each worker. Measurements of unbound mercury in urine samples were sensitive at picking up minimal exposures. Excessive amounts of unbound mercury were not found in the urine, even with wide day-to-day swings in microenvironmental mercury vapor levels, suggesting that the human body can adapt to a chronic, moderate exposure to mercury vapor.

Evaluation of mercury in urine as an indicator of exposure to low levels of mercury vapor.

“…Mattiussi et al (1982), however, report that their results using either type of samplers were similar. In the second group, all but Stopford et al (1978) used static area air samplers. To evaluate whether predicted urinary levels at low airborne concentrations can be distinguished from background urinary mercury levels, urinary mercury predictions were examined near and below the lower limit of the data for the various log-log regression equations (Table 5) Lindstedt et al (1979), study II Bell et al (1973) Stopford et al (1978 × whereas the higher predictions (based primarily on static air sampling data) are above the background range.…”

“…Lindstedt et al (1979) Static samples; daily for Spot samples (not SG Thirteen individual means in a chloralkali plant (Figure 2) 1-4, 6,7 Study I 2 weeks (TWA) corrected) daily (postshift) for 2 weeks Lindstedt et al (1979) Personal samples; daily for Spot samples twice a week for Fifteen individual means in chloralkali plant (Figure 3) 1-6 Study II 8 weeks (TWA) 8 weeks (postshift) Mattiussi et al (1982) Static samples over Sample type and duration not Twenty-one group means of 275 workers from nine job 1, 3, 4, 6, 7 1-3 years (TWA) reported specified classes in five chloralkali plants (Figure 1) as identical to personal sampling Muller et al (1980) Personal samples for Four samples (SG corrected = Fifteen individual means of cellroom operators (five per 1-7 8-9 hr over 10 days 1.017) over a day plant) in three NaCl electrolysis plants (Table 1) (TWA) (morning/home, preshift, midshift, postshift) Nordhagen et al (1994) Static samples; twice a Quarterly samples (type and Thirty-four group annual averages of 419 workers in four job 1-4, 7 week at 130 points. Annual SG correction not reported) classes of a chloralkali plant study (Figure 4) means 1953-1987 based on quarterly means Roels et al (1987) Personal samples; 6 hr over 9 A.M. spot samples for 5 days c Ten individual means of two to four samples matched to 1-7 5 days (TWA) previous day's TWA sample from a distinct work area in dry alkaline battery plant (Figures 2, 4, 5) Smith et al (1970) Static samples collected Unspecified sample type Eighteen group means of 560 workers in 21 chloralkali 1-4, 7 six times a year (TWA) four times per year plants ( Figure 5) Stopford et al (1978) Personal samples urine samples separately for analysis from data on group means of several workers. The combined data set and the separate groups were analyzed using standard linear regression techniques and SYSTAT 9 statistical software (SPSS 1999).…”

“…Many studies have also found a strong correlation between the level of mercury in urine and the level of elemental mercury in air in occupational settings where exposures are relatively high (Ehrenberg et al 1991;Nordhagen et al 1994;Roels et al 1987;Schaller and Triebig 1984;Stopford et al 1978). Less understood is whether exposures at much lower airborne mercury levels (i.e., 1-10 µg/m 3 ) can be detected in urine above background levels.…”

Relation of mercury exposure to elemental mercury levels in the urine and blood.

“…On the other hand, elemental mercury has been detected in the urine of workers exposed to mercury vapor (5,14,15). The occurrence of trace amounts of elemental mercury is considered to be due to (i) the reduction of mercuric ion by certain types of microorganisms present in the urine and (ii) direct urinary excretion following glomerular filtration of the elemental mercury persisting in the blood.…”

Analysis of mercury in hair of EPA Region V population

“…Subsequent studies have shown that most forms of mercury entering the aquatic environment can be transformed by the action of microorganisms to methylmercury, which accumulates in fish (Callahan et al, 1979;ATSDR, 1995;Mason et al, 1995). Although human exposure to mercury can result from a number of sources and through various pathways, the general population is predominantly exposed to mercury in the diet, with methylmercury residues in fish being the dominant dietary source of exposure (Stopford et al, 1978;Simpson et al, 1974). The general population is also exposed to mercury vapors released from dental fillings (Engle et al, 1992).…”