Hormone status in occupational toluene exposure

Area of Science:

• Occupational Health
• Endocrinology
• Toxicology

Background:

• Toluene is a common industrial solvent used in printing.
• Previous studies suggest potential neurotoxic effects of toluene.
• The impact of toluene on the endocrine system, particularly reproductive hormones, requires further investigation.

Purpose of the Study:

• To investigate the effects of occupational toluene exposure on reproductive hormone levels in rotogravure printers.
• To assess the reversibility of these effects after reduced exposure.

Main Methods:

• Cross-sectional study comparing 20 toluene-exposed printers with 44 unexposed referents.
• Measurement of plasma follicle stimulating hormone (FSH), luteinizing hormone (LH), and serum free testosterone.
• Assessment of toluene levels in air, blood, and adipose tissue.
• Monitoring of hormone levels in a subset of printers before and after a 4-week vacation.

Main Results:

• Printers exhibited significantly lower median plasma FSH and LH levels, and lower serum free testosterone compared to referents.
• A negative association was observed between blood toluene levels and plasma prolactin.
• Hormone levels (FSH, LH) increased, while thyroid hormones decreased in printers after a 4-week vacation.

Conclusions:

• Occupational toluene exposure, even below permissible limits, may cause slight, reversible alterations in the hypothalamic-pituitary axis.
• Potential mechanisms may involve effects on catecholamine neurotransmission.
• Further research is warranted to fully understand the endocrine-disrupting potential of toluene.