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

MERCURY
2. HEALTH EFFECTS
results, the authors concluded that mercury in the manufacturing process may not have been the clastogen.
Other genotoxicity studies are discussed in Section 2.5.
2.2.1.8 Cancer
Metallic Mercury. There is no evidence from epidemiological studies that indicates inhalation of metallic
mercury produces cancer in humans (Cragle et al. 1984; Kazantzis 1981). No evidence of an association
between metallic mercury exposure and cancer mortality was found in a group of workers employed in a
facility utilizing the metal in a lithium isotope separation process (Cragle et al. 1984). Overall mortality in
the mercury-exposed group was less than that of the standard white male population and that of a control
group of men who were not exposed to mercury. Similarly, no excess of cancer of the kidneys or nervous
system was found among a cohort of 674 Norwegian men exposed to mercury vapors for more than 1 year
at 2 chloralkali plants (Ellingsen et al. 1993). An excess in lung cancer (type not specified) was found in
Swedish chloralkali workers 10 years after the end of long-term, high-level exposure to metallic mercury
(Barregard et al. 1990). However, these workers had also been exposed to asbestos. Furthermore, no data
on smoking status was provided, although the study implied that the workers did not smoke much.
No studies were located regarding cancer in animals after inhalation exposure to metallic mercury.
Organic Mercury. Associations were reported between the use of mercury-containing fungicides (i.e.,
mercury levels in hair) and leukemia in farmers and between the use of mercury-containing seed dressings
and leukemia in cattle (Janicki et al. 1987). However, the study was limited in reporting methodology used
to conduct this study. Furthermore, the study did not adequately address exposure to other chemicals, or
adjust for other leukemia risk factors.
No studies were located regarding cancer in animals after inhalation exposure to organic mercury.
2.2.2 Oral Exposure
The bulk of the information regarding toxicity resulting from oral exposure to inorganic mercury comes
from studies of mercuric chloride. However, a few studies are also available on the effects of oral exposure
to mercuric acetate, mercurous chloride (calomel), and mercuric sulfide (cinnabar). Discussion of these
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