Studies of lead exposure on reproductive system: a review of work in China

This paper, based on a review of a series studies conducted in China from 1978 through 1991, describes the possible links between low level lead exposure and the adverse effects on reproductive system. Effects on menstrual status and pregnancy outcome manifested mainly as higher prevalences of menstrual disturbance, spontaneous abortion and threatened abortion in exposed females. Transfer of lead via placenta and human milk was shown by higher lead levels in milk and blood of infant. Impairment of male reproductive function was observed as decreased volume of ejaculation, prolonged latency of semen melting, reduced total sperm count and alive spermatozoa, retarded sperm activity as well as lowered density of semen fluid in exposed male workers with Pb-B over 40 micrograms.dl-1. In addition, poorer performance of WISC-R test was revealed in children with Pb-B level over 30 micrograms.dl-1, and retarded physical development was observed in children with Pb-B over 20 micrograms.dl-1. Therefore, health surveillance including the assessment of adverse effects on reproductive system of both female and male lead exposed workers should not be ignored. Furthermore, safety exposure limit of work place, particularly for female workers of child-bearing age, should be developed.