IARC MONOGRAPHS ON THE EVALUATION OF CARCINOGENIC ...

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(Scheepers & Bos, 1992). The average concentration of naphthalene reported inside
automobiles in commuter traffic was about 4.5 μg/m 3 (Löfgren et al., 1991).
(b) Water
IARC MONOGRAPHS VOLUME 82
Naphthalene released to the atmosphere may be transported to surface water and/or
soil by wet or dry deposition. About 2–3% of naphthalene emitted to air is transported to
other environmental media by dry deposition (Coons et al., 1982; Agency for Toxic
Substances and Disease Registry, 1995a). Naphthalene is degraded in water by photolysis
and biological processes. The half-life for photolysis of naphthalene in surface
water is about 71 h, but in deeper water (5 m) it is estimated to be 550 days (Agency for
Toxic Substances and Disease Registry, 1995a).
Surface water discharges of naphthalene from 744 industrial facilities in the USA in
1999 amounted to 17.7 tonnes, as reported to the Toxics Release Inventory. An additional
73 tonnes of naphthalene were discharged though underground injection (Environmental
Protection Agency, 2001). About 5% of all naphthalene entering the environment is
released to water, mostly arising from coal tar production and distillation processes
(Agency for Toxic Substances and Disease Registry, 1995a).
Naphthalene was detected in 7% of 630 ambient water samples in the USA at a
median concentration of less than 10 μg/L, as shown in an analysis of 1980–82 data from
the Environmental Protection Agency STORET (STOrage and RETrieval) database
(Staples et al., 1985; Agency for Toxic Substances and Disease Registry, 1995a).
Naphthalene was also detected in 11% of 86 urban run-off samples up to 1982 at concentrations
ranging from 0.8 to 2.3 μg/L (Cole et al., 1984).
In the USA, naphthalene was detected in 35% of samples of groundwater at an
average concentration of 3.3 mg/L at five wood-treatment facilities (Rosenfeld & Plumb,
1991) and in leachate or groundwater plume from industrial and municipal landfills at
concentration ranges of < 10–19 mg/L and 0.1–19 mg/L, respectively (Brown & Donnelly,
1988). Naphthalene was detected in groundwater samples from three wells at concentrations
of 380, 740 and 1800 μg/L, respectively, near an underground coal gasification
site in north-western Wyoming (Stuermer et al., 1982). Concentrations of naphthalene
ranging from < 0.2 to 63 μg/L were detected at five out of six landfill sites in southern
Ontario (Barker, 1987). Naphthalene was found at concentrations of 4.3 and 8.8 μg/L in
two groundwater samples collected near an Orange County landfill site in central Florida
(and not in surface water) in 1989–90, but not in 1992–93; this was believed to result from
the decomposition of municipal solid waste (Chen & Zoltek, 1995).
Naphthalene has been infrequently reported in drinking-water (Agency for Toxic
Substances and Disease Registry, 1995a). It was found in four samples of drinking-water
extracts at concentrations ranging from 6 to 16 ng/L in Athens, GA, in 1976 (Thruston,
1978) and in another area in the USA at concentrations up to 1.4 μg/L (Coons et al.,
1982).
Naphthalene was measured in samples of raw river water from the Adige River, Italy,
collected at 19 sampling stations in the Trento province, during two campaigns in 1989,