IARC MONOGRAPHS ON THE EVALUATION OF CARCINOGENIC ...

NAPHTHALENE 379
A median naphthalene concentration of 0.18 ppb [0.94 μg/m 3 ] has been reported in
urban air in 11 cities in the USA (Howard, 1989). An average naphthalene concentration
of 170 μg/m 3 in outdoor air in a residential area of Columbus, OH (Chuang et al., 1991)
and a concentration of 3.3 μg/m 3 naphthalene in ambient air in Torrance, CA, have also
been reported (Propper, 1988; Agency for Toxic Substances and Disease Registry, 1995a).
Average naphthalene concentrations in ambient air at five hazardous waste sites and
one landfill in New Jersey ranged from 0.42 to 4.6 μg/m 3 (range of arithmetic means)
(LaRegina et al., 1986). Naphthalene wasfound at concentrations of less than 0.6 ng/m 3
in the air above shale-oil wastewaters in Wyoming (Hawthorne & Sievers, 1984).
Naphthalene was found in particulate matter in the atmosphere of La Plata,
Argentina, at concentrations ranging from 0.18 ± 1.05 ng/m 3 to 13.2 ± 1.30 ng/m 3 when
sampled on seven occasions between September 1984 and June 1986 (Catoggio et al.,
1989).
In a study to compare naphthalene concentrations (among 35 volatile organic compounds)
in indoor and outdoor air in northern Italy in 1983–84, the mean values found
in indoor and outdoor samples were 11 and 2 μg/m 3 , respectively, with the median
indoor/outdoor ratio being 4 for 11 samples (De Bortoli et al., 1986).
Average indoor air concentrations in various residential areas in the USA ranged
from 0.75 to 1600 μg/m 3 (Chuang et al., 1991 (measurements done in 1986–87); Wilson
& Chung, 1991). A more representative upper limit concentration of naphthalene in
indoor air of 32 μg/m 3 was recorded in buildings in heavy traffic urban areas of Taiwan
(Hung et al., 1992).
In a study of the effect of smoking on polycyclic aromatic hydrocarbon levels,
including naphthalene, in eight homes in the USA, naphthalene was found in the living
room of homes of smokers (with gas heating and electric cooking) and homes of nonsmokers
(electric heating and cooking) at concentrations of 2.2 μg/m 3 and 1.8 μg/m 3 ,
respectively, and the respective outdoors concentrations of naphthalene were 0.33 and
0.11 μg/m 3 (Wilson & Chuang, 1991).
In a summary of concentrations of volatile organic compounds in 230 homes in
Germany, naphthalene was found at a mean concentration of 2.3 μg/m 3 with a range of
< 1.0–14 μg/m 3 ; the 50th and 90th percentiles were 2.1 and 3.9 μg/m 3 , respectively
(Gold et al., 1993). In a study of the relationship between climatic factors and the
concentrations of 26 volatile organic compounds in Canadian homes in 1991, naphthalene
concentrations in the winter, spring, summer and autumn were 3.24, 1.10, 3.82 and
8.10 μg/m 3 , respectively (Fellin & Otson, 1994). In a comparison of naphthalene
concentrations in the indoor air of 50 normal and 38 ‘sick’ homes (in which people
complained about the odour or had symptoms) in Finland, naphthalene was found at a
median concentration of 0.31 μg/m 3 in normal homes (with 6% of normal houses having
1.5–3.1 μg/m 3 ), while in ‘sick’ homes 2.6% had concentrations of 1.5–3.1 μg/m 3 , 5.3%
of 3.1–15 μg/m 3 and 5.3% of 15–62 μg/m 3 (Kostiainen, 1995).
Naphthalene has been identified in the emissions of diesel light-duty vehicles
(2–6 mg naphthalene released per km ‘distance’ driven on a chassis dynamometer)