Urban stressors and thyroid hormones

OBJECTIVES: The aim of the study is to evaluate whether occupational exposure to urban stressors could cause alterations in thyroid hormones plasma levels (TSH, FT3 and FT4) in female outdoor workers vs. administrative. MATERIALS AND METHODS: The study has been performed on an initial sample of 198 female subjects divided in two groups (occupationally exposed and not exposed to urban stressors). After excluding the subjects with the main confounding factors, female outdoor workers and administrative staff were matched by age, working life and drinking habit. RESULTS: In 40 female outdoor workers mean plasma TSH levels were significantly higher compared to 40 administrative staff. The distribution of TSH values in outdoor workers and in administrative staff was significant. Plasma FT3 and FT4 levels were not significantly different in the two groups. Our results suggest that exposure to urban stressors (chemical, physical and psycho-social), can alter the plasma concentration of TSH. CONCLUSIONS: According to our previous research, plasma TSH levels may be used as an early biological marker of chronic exposure to urban stressors, in occupational set even before the onset of the related disorders.