Sperm Count Suppression without Endocrine Dysfunction in Lead-Exposed Men

Abstract

To determine if increased lead absorption was associated with sperm count suppression or perterbation of the hypothalamopituitary system, we compared battery workers (N = 18), who were exposed to high airborne lead levels, with cement workers (N = 18), who were exposed to ambient lead levels. Blood lead, urinary lead, semen lead, and zinc protoporphyrin concentrations were markedly elevated (p less than .001) in battery workers. Battery workers had a significantly shifted (p less than .025) frequency distribution of sperm count (median count, 45 vs. 73 X 10(6) cells/cc, respectively). There were no significant differences between the two groups in mean follicle-stimulating hormone, testosterone, prolactin, luteinizing hormone, or total neutral 17-ketosteroid levels. Potential confounding factors (alcohol, cigarette, and coffee consumption, frequency of intercourse, and days of abstinence prior to semen donation) were not significantly different between the two groups. These results suggest a direct toxic effect of increased lead absorption on sperm production or transport in man.

Current issues in the epidemiology and toxicology of occupational exposure to lead.

“…Corroboration of these findings is provided by two recent studies, which also observed sperm count depression at relatively high blood lead levels (> 60 jig/dL) (49,50).…”

Reproductive Toxicity of Metals in Men

“…Effects on the reproductive endocrine function have been less consistent (71,74,(79)(80)(81)(82)(83). Reduced sperm count and concentration, and lower motility were found in lead workers with blood lead levels lower than 400 µg L -1 (78,(84)(85).…”

“…In men occupationally exposed to lead, blood lead levels equal to or higher than 400 µg L -1 have been associated with reduced sperm count, poor semen motility, and abnormal sperm morphology, particularly of the sperm head (69)(70)(71)(72)(73)(74)(75)(76)(77)(78). Effects on the reproductive endocrine function have been less consistent (71,74,(79)(80)(81)(82)(83).…”

Occupational and Lifestyle Exposures on Male Infertility: A Mini Review

“…Males employed in metal industries had a decreased fertility when compared with other workers as shown by a delayed pregnancy and reduced semen quality [26,36,45,[63][64][65][66][67][68][69]. Akinloye et al [68] analyzed the serum and seminal plasma concentrations of cadmium (Cd) in 60 infertile males and 40 normozoospermic subjects.…”

“…1). Any of those mechanisms would result in poor semen quality [26,36,37]. Recent studies suggest that sperm DNA integrity may be altered by environmental exposure to some toxic chemicals [38,39].…”