Large-scale mercury exposure due to a cream cosmetic: community-wide case series.

OBJECTIVE To describe demographic characteristics, patterns of use, reported symptoms, and laboratory results associated with mercury exposure among people who used a beauty cream containing mercury. DESIGN. Descriptive study of a case series. SETTING The Hong Kong community. PARTICIPANTS Users of a cream cosmetic who contacted the Department of Health following a public announcement. MAIN OUTCOME MEASURES Urine and blood mercury concentrations, cream mercury content, self-reported symptoms, duration of cream use, and duration since last cream use. RESULTS We interviewed 314 cream users, 99% of whom were women. The mean urine and blood mercury concentrations of 286 users, who submitted a urine or blood sample, were 45.2 microg/L (reference level, <20 microg/L) and 17.1 microg/L (reference level, <10 microg/L), respectively; 65% of these participants had elevated mercury concentrations. The mercury content of the cream cosmetic ranged from 660 to 57 000 ppm. Seventy-eight percent of all cream users reported no symptoms, but absence of symptoms was not predictive of low urine and blood mercury concentrations. Urine mercury concentrations were significantly higher among people who last used the cream within 45 days. Blood mercury concentrations were elevated following cream use for as short as 2 days. CONCLUSIONS The majority of cream users had increased urine or blood mercury concentrations but remained asymptomatic, implying that the incidence of overt symptomatic mercury poisoning resulting from dermal application of creams with mercury content lower than 57 000 ppm is low. Doctors should take a history of the use of cosmetics if patients have clinical or laboratory evidence of mercury exposure; such cases should be reported to public health authorities.