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

MERCURY 346
2. HEALTH EFFECTS
Reproductive Toxicity. Occupational exposure to metallic mercury has not been shown to result in
statistically significant effects on male fertility (Alcser et al. 1989; Lauwerys et al. 1985). However, an
increase in the rate of spontaneous abortions may occur (Cordier et al. 1991). A spontaneous abortion
occurred in a female after ingesting an acute dose of mercuric chloride (Afonso and deAlvarez 1960).
There were no studies available on dermal exposure to metallic, inorganic, or organic mercury.
Additional epidemiological studies on inhalation and dermal exposure to mercury are needed to evaluate
the threshold of reproductive effects in workers (including dentists and dental assistants).
Inorganic mercury exposure caused a significant increase in the incidence of resorptions in hamsters
(Gale 1974). Abortions and decreased mean litter size have been observed in rats, mice, guinea pigs, and
monkeys following oral exposure to organic mercury (Burbacher et al. 1988; Hughes and Annau 1976;
Inouye and Kajiwara 1988; Khera 1973). There was a decrease in conceptions and an increase in early
abortions and stillbirths in female monkeys exposed orally to methylmercury for 4 months, but the
menstrual cycle length was not affected (Burbacher et al. 1988). However, prolonged estrous cycles were
found in rats inhaling metallic mercury (Baranski and Szymczyk 1973). Adverse effects on
spermatogenesis and on histopathology of the testes have been reported in several studies in animals
exposed to methylmercury (Hirano et al. 1986; Mitsumori et al. 1990; Mohamed et al. 1987). There was
no information on reproductive effects following dermal exposure to mercury in animals. A 90-day study
is needed to provide reproductive organ pathology data on male and female animals. Multigenerational
studies for inorganic and organic mercury are also needed. Additional reproductive studies are needed
because reproductive-aged populations near hazardous waste sites might be exposed to mercury.
Developmental Toxicity. Occupational exposure to metallic mercury in males did not result in
statistically significant effects on malformations or the number of children born (Alcser et al. 1989;
Lauwerys et al. 1985). The results from an inhalation developmental rat study (Baranski and Szymczyk
1973) suggest that metallic mercury vapors may cause a higher incidence of fetal malformations,
resorptions, and deaths. Dermal studies on metallic mercury in humans and animals were not available.
Additional well-conducted inhalation and dermal studies on metallic mercury in animals are needed to
evaluate the potential for adverse developmental effects to humans from mercury.
Inorganic mercury exposure caused a significant increase in the incidence of resorptions in hamsters
(Gale 1974). No other human or animal studies were available on developmental effects following
inorganic mercury exposure. Therefore, additional studies for inhalation, oral, and dermal exposures are