Health effects of long-term mercury exposure among chloralkali plant workers

Abstract

Background Inorganic mercury is toxic to the nervous system, kidneys, and reproductive system. We studied the health effects of mercury exposure among former employees of a chloralkali plant that operated from 1955 to 1994 in Georgia. Methods Former plant workers and unexposed workers from nearby employers were studied. Exposure was assessed with a job‐exposure matrix based on historical measurements and personnel records. Health outcomes were assessed with interviews, physical examinations, neurological and neurobehavioral testing, renal function testing, and urinary porphyrin measurements. Exposure–disease associations were assessed with multivariate modeling. Results Exposed workers reported more symptoms, and tended toward more physical examination abnormalities, than unexposed workers. Exposed workers performed worse than unexposed subjects on some quantitative tests of vibration sense, motor speed and coordination, and tremor, and on one test of cognitive function. Few findings remained significant when exposure was modeled as a continuous variable. Neither renal function nor porphyrin excretion was associated with mercury exposure. Conclusions Mercury‐exposed chloralkali plant workers reported more symptoms than unexposed controls, but no strong associations were demonstrated with neurological or renal function or with porphyrin excretion. Am. J. Ind. Med. 39: 1–18, 2001. © 2001 Wiley‐Liss, Inc.

Does Inorganic Mercury Play a Role in Alzheimer's Disease? A Systematic Review and an Integrated Molecular Mechanism

“…Five of these studies were on groups of workers after their exposure, four were case histories. Four studies [70][71][72][73] show evidence that workers exposed to mercury 5 to 18 years previously still had significantly worse results in neurological tests and clinical symptoms than those without significant exposure, even though one study had excluded all neurologically and psychiatrically ill persons. The study that found no significant differences [74] investigated workers 30 years after exposure.…”

Renal function of chloralkali workers after the cessation of exposure to mercury vapor

“…Our results of the U-NAG activities and U-Alb concentrations, being similar for the workers previously exposed and for the referents, support the results from previous studies (16,17). Our observation that the increase in U-NAG among the exposed persons between the two examinations was lower than for the referents may suggest that at least the U-NAG activities normalize after the cessation of exposure.…”

“…Former chloralkali workers had no different level of serum creatinine, creatinine clearance, U-Alb, or U-NAG 5.7 years, on the average, after the cessation of exposure than their referents (16). Likewise, no differences for U-Alb, anti-GBM, or U-NAG were found about 12 years after exposure cessation between formerly exposed persons and referents (17).…”

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