Mechanism of lead induced effects on human spermatozoa after occupational exposure.
OBJECTIVE
Occupational lead exposure caused several types of male reproductive impairments in different working populations. In the present study we examined the paint factory workers of active reproductive age and compared the data with the non-occupationally exposed desk job holders taken as control from Bangalore, India.


METHODS
In the above perspective, sperm cell morphology, morphometery and motile activity were assessed. Routine seminal biochemistry, cell cycle phase analysis of sperm head DNA, estimation of serum reproductive hormones and metal levels in blood and semen were also taken into account.


RESULTS
Low sperm velocity, ATPase activity, gross and forward progressive motility with high stationary motile spermatozoa revealed lowering of cellular activity after lead exposure (p<0.001), which was supported by high seminal plasma fructose level (p<0.001). Lowering of seminal plasma total protein with concomitant rise in free amino acid level was prevalent as the exposure increased (p<0.001), suggesting disturbance in cellular nutritional support essential for cellular motility. Prolonged liquefaction time, reduced semen volume and viscosity as well as altered seminal plasma protein, fructose and cholesterol level among the workers indicated dysfunction of accessory sex glands viz. prostate and seminal vesicle after occupational lead exposure (p<0.001). Deterioration of sperm count, structural abnormality of spermatozoa and sperm head DNA hyploidy was also associated with high blood and semen lead levels in the paint factory workers (p<0.001) without interfering serum FSH, LH and testosterone level (non-significant at p<0.05).


CONCLUSIONS
Therefore, the present study suggested that at the present exposure level lead might cross blood-testis-barrier and increased its value in semen of the occupationally exposed paint factory workers in Bangalore, India, thereby producing detrimental effects on semen quality and sperm characteristics.
Naha
N
N
The Oxford College of Physiotherapy, Bangalore, India. niv_639@yahoo.co.in
Manna
B
B
D000328:Adult; D000704:Analysis of Variance; D006801:Humans; D007194:India; D007854:Lead / Q000633:toxicity*; D008297:Male; D008875:Middle Aged; D016273:Occupational Exposure / Q000009:adverse effects*; D010150:Paint / Q000633:toxicity; D012661:Semen / Q000187:drug effects; D013076:Sperm Count; D013081:Sperm Motility / Q000187:drug effects; D013094:Spermatozoa / Q000187:drug effects*; D011795:Surveys and Questionnaires; D013739:Testosterone / Q000097:blood
D007854:Lead; D013739:Testosterone