Concentration of trace metals in blood and the relationship with reproductive hormones (estradiol and progesterone) of obese females living around a mining area in Brits, South Africa

Obesity is a rapidly growing problem in South Africa, with 70% of women reported as being obese. Studies have reported that high levels of trace metals may impair the production of reproductive hormones, which may, in turn, interfere with normal oocyte development in females. This study investigated the concentrations of trace metals in blood samples of obese individuals living around a mining industry and examined the overall effect on reproductive hormones of these obese females. A mixed-method research approach consisting of qualitative and quantitative (cross-sectional descriptive survey) was used in the study. Only females with BMI ≥ 30 were allowed to participate in the study. Blood samples were collected in two 5 mL tubes from each of the participants. Concentrations of trace metals in the blood samples were determined by the use of ICP-MS. Hormonal level measurement was also carried out. The results showed that the trace metal concentrations in the blood samples of participants were in the order Mn > Cr > Co > As > Pb > Cd. The mean concentrations of Mn, Cr, Co and As were above the WHO standards. The hormonal analysis showed that there was a positive correlation between estradiol and progesterone levels with Mn concentration. Cr and As concentrations showed a negative correlation between estradiol and progesterone levels. Also, a negative correlation was established between estradiol levels with Pb and Cd concentrations. The study showed that exposure to trace metals as pollutants may have an impact on the general and reproductive health of obese females living around mining activities.