revised final - Agency for Toxic Substances and Disease Registry ...

MERCURY 410
5. POTENTIAL FOR HUMAN EXPOSURE
5.4 LEVELS MONITORED OR ESTIMATED IN THE ENVIRONMENT
Reliable evaluation of the potential for human exposure to mercury and various mercury compounds
depends in part on the reliability of supporting analytical data from environmental samples and biological
specimens. Concentrations of mercury in unpolluted atmospheres and in pristine surface waters are often so
low as to be near the limits of detection of current analytical methods even for determining total mercury.
In reviewing data on mercury levels monitored or estimated in the environment, it should also be noted that
the amount of chemical identified analytically is not necessarily equivalent to the amount that is
bioavailable. The analytical methods available for monitoring mercury and various inorganic and organic
mercury compounds in a variety of environmental media are discussed in Chapter 6.
5.4.1 Air
Indoor air mercury concentrations were determined in 37 houses in Ohio that had been painted with latex
paint (Beusterien et al. 1991). Of the 37 homes studied, 21 homes had been painted with interior latex paint
containing mercury a median of 86 days earlier, while the 16 control homes had not been recently painted
with mercury-containing latex paints. Paint samples from the exposed homes contained a median
concentration of 210 mg/L (ppm) (range, 120–610 mg/L). The median air mercury concentration
(0.3 µg/m 3 ) was found to be significantly higher (p