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

MERCURY
2. HEALTH EFFECTS
A 39-year-old farmer who had treated seeds with phenylmercuric acetate for 6–7 seasons died within several
months of developing severe neurological toxicity (Brown 1954).
Four rats died soon after developing severe ataxia following inhalation of unspecified concentrations of
methylmercury iodide vapor for 22 days (Hunter et al. 1940).
2.2.1.2 Systemic Effects
The highest NOAEL values and all reliable LOAEL values for systemic effects in each species and duration
category are recorded in Table 2-1 and plotted in Figure 2-1.
Respiratory Effects
Metallic Mercury. In humans, respiratory symptoms are a prominent effect of acute-duration high-level
exposure to metallic mercury vapors. The most commonly reported symptoms include cough, dyspnea, and
tightness or burning pains in the chest (Bluhm et al. 1992a; Gore and Harding 1987; Haddad and Sternberg
1963; Hallee 1969; Kanluen and Gottlieb 1991; King 1954; Lilis et al. 1985; Matthes et al. 1958; McFarland
and Reigel 1978; Milne et al. 1970; Rowens et al. 1991; Snodgrass et al. 1981; Soni et al. 1992; Taueg et al.
1992; Teng and Brennan 1959; Tennant et al. 1961). X-ray analyses of the lungs have primarily shown
diffuse infiltrates or pneumonitis (Bluhm et al. 1992a; Garnier et al. 1981; Gore and Harding 1987; Hallee
1969; King 1954; Soni et al. 1992; Tennant et al. 1961). Pulmonary function may also be impaired. Airway
obstruction, restriction, hyperinflation (Snodgrass et al. 1981), and decreased vital capacity (Lilis et al. 1985;
McFarland and Reigel 1978) have been reported. The decreased vital capacity observed by Lilis et al.
(1985) persisted for 11 months after exposure. In the more severe cases, respiratory distress, pulmonary
edema (alveolar and interstitial), lobar pneumonia, fibrosis, and desquamation of the bronchiolar epithelium
have been observed. The ensuing bronchiolar obstruction by mucus and fluid results in alveolar dilation,
emphysema, pneumothorax, and possibly death (Campbell 1948; Gore and Harding 1987; Jaffe et al. 1983;
Kanluen and Gottlieb 1991; Matthes et al. 1958; Taueg et al. 1992; Teng and Brennan 1959; Tennant et al.
1961).
Little information is available regarding exposure levels resulting in the above symptoms. However,
workers accidentally exposed to mercury vapors at an estimated concentration of up to 44.3 mg/m 3 for
4–8 hours exhibited chest pains, dyspnea, cough, hemoptysis, impairment of pulmonary function (i.e.,
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