Bisphenol A levels among workers in plastic processing industry and their relations to thyroid hormones

ABSTRACT

Bisphenol A (BPA) is widely used in the plastic processing industry. A cross-sectional study was conducted to measureBPA levels in the serum of workers as a biomarker of occupational exposure, investigate the thyroid hormone profileamong BPA exposed workers, and identify the relationship between occupational exposure to BPA and thyroidhormones during. Our data indicate that the studied workers had higher BPA level than that reported for the Egyptiangeneral population, with a median serum level of 15.6 ng/ml and ranged from 1.6 to 62.9 ng/ml while the interquartilerange was 16.3 ng/ml, the highest concentration was among the workers of recycling followed by squeegees and PVCdepartments. As regards thyroid hormones, almost one-third of the studied workers had abnormal thyroid-stimulatinghormone (TSH) levels and 12.2% had abnormal T4 levels. According to TSH and T4 levels, 64.4% of the studiedworkers had normal thyroid function and 35.6% were suffering from subclinical hypothyroidism. No significantcorrelation between BPA levels and subclinical hypothyroidism was statistically reported. However, our data reporteda significant positive correlation between thyroid hormone T3 and serum BPA concentrations. As agonist or antagonist,BPA could bind to the thyroid hormone receptors indicating that remarkable endocrine disruption.