Whole blood mercury concentrations in sub-fertile men in Hong Kong

We aimed to investigate the association between whole blood mercury concentrations and semen quality in sub-fertile men. Fifty-nine male partners of infertile couples attending the Assisted Reproduction Unit of the Chinese University of Hong Kong between 1997 and 1998 were recruited into our study. Blood was taken from each subject for whole blood mercury concentration and hormone profile. Semen samples were obtained for computer assisted semen analysis using the Hobson sperm tracker. The semen parameters and hormone profile were compared between subjects with normal and those with elevated mercury concentrations. Twenty-one subjects (35.6%) had a whole blood mercury concentration higher than the normal range (0-50 nmol/l). All parameters of the semen analysis including the concentration of sperm, percentage of morphologically normal sperm, percentage of motile sperm, curvilinear velocity, straight-line velocity, average path velocity, and amplitude of lateral head displacement, were reduced in those with elevated blood mercury concentrations, although the difference was not statistically significant. We failed to demonstrate a statistically significant effect on the measurement of semen quality, but other adverse effects cannot be excluded. From a public heath perspective, these findings confirm that mercury toxicity is a potentially serious problem affecting the local community.