Endocrine and Reproductive Dysfunction in Men Associated with Occupational Inorganic Lead Intoxication

Abstract

In an attempt to define a postulated effect of lead on male endocrine function, seven men with symptomatic occupational lead intoxication (maximum whole blood lead levels 66-139 micrograms/dl) underwent in-patient endocrine evaluation at the time of diagnosis. Defects in thyroid function, probably of central origin, were present in three patients. Six patients had subnormal glucocorticoid production measured by 24-hr urinary 17-hydroxycorticosteroids and plasma cortisol responses to vasopressin- and/or insulin-induced hypoglycemia. Although serum testosterone concentration was normal in six patients, five had defects in spermatogenesis, including two with oligospermia and two with azoospermia. Repeat examinations after chelation therapy showed only partial improvement. It is concluded that heavy occupational exposure to lead, sufficient to cause clinical poisoning, may be associated with diffuse disturbances of endocrine and reproductive functions in men which are not rapidly reversible with standard treatment. Since men without overt poisoning have not been studied, these results cannot yet be included as sequelae of low-dose exposures.

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

“…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).…”

Lead Exposure and Environmental Health

“…Changes in circulating levels of thyroid hormones, particularly serum thyroxine (T4) and thyroid stimulating hormone (TSH), generally occurred in workers having mean Pb blood ≥ 40-60 μg/dL (Cullen et al, 1984). Altered serum levels of reproductive hormones, particularly follicle stimulating hormone (FSH), luteinizing hormone (LH), and testosterone, have been observed at Pb blood ≥ 30 -40 μg/dL.…”