Effect of Oil Paint Fumes Inhalation on the Level of Serum Thyroid Hormones and Thyroid Stimulating Hormone in Rats

Aims: The exposure to chemical materials and colors affects thyroid gland functions. The aim of this study was to investigate the effects of fume inhalation of oil-based paints on the serum level of thyroid hormones in female and male rats. Materials & Methods: In the experimental study, 15 male and 15 female Wistar rats were studied. The rats were divided into six 5-rat groups including a control group and groups with either 1or 8-hour a day exposure to the paint fumes by gender division. The serum levels of T3, T4, and TSH thyroid hormones were measured after 10 weeks. Data was analyzed by SPSS 20 software using two-way ANOVA and Tukey’s post-hoc. Findings: Mean values of T3 and T4 hormones were significantly reduced in both 1and 8-hour male and female groups than control group (p<0.001). In addition, the more the inhalation time, the more the reduction was. Any reduction in T3 in females in 1-hour (p<0.001) and 8–hour (p<0.05) groups was significantly more than the males. Nevertheless, a significant reduction in T4 was only in 1-hour group (p<0.001). Mean TSH hormone was significantly increased due to the inhalation of paint fume than control group (p<0.001). In addition, such an increase was significant in the female rats in 8-hour group than the male group (p<0.01). Conclusion: The inhalation of oil-based paint fume leads to a reduction in the serum levels of T3 and T4 thyroid hormones, while increases TSH serum level. Such an effect is stronger in the females.