Elemental Status and Lipid Peroxidation in the Blood of Children with Endemic Fluorosis

The study aimed to assess the levels of trace elements, minerals, and toxic elements as well as lipid peroxidation biomarkers (lipid acyl hydroperoxides, 2-thiobarbituric acid reactive substances (TBARS)) in the blood of children with chronic fluorosis from endemic fluorosis areas (Sosnivka village, Lviv region, western Ukraine). The results were compared with healthy children from Staryi Sambir (Lviv region, western Ukraine), whose drinking water contained permissible levels (< 1 ppm) of fluoride. Thirty-one children from the Sosnivka village in the Lviv region, including 16 females and 15 males aged 7-10 years, with clinically diagnosed fluorosis, were recruited for the study. The children had been exposed to fluoride (> 1.5 ppm) through drinking water for more than 5 years. In the blood, eight macro- and microelements (calcium, zinc, potassium, iron, copper, selenium, manganese, chromium), five additional elements (sulfur, bromine, chlorine, nickel, strontium), and four toxic elements (lead, mercury, cadmium, mercury) were assessed with the X-ray fluorescence method. The results of our study demonstrated a 14-fold decrease in the copper level, a 2.5-fold decrease in the calcium and zinc levels, and a 2-fold decrease in the selenium level in the blood of children with chronic fluorosis compared with the healthy children from the non-fluorosis area. In turn, a 1.7- and 1.4-fold increase in the strontium and lead content, respectively, was noted. The sulfur, chlorine, potassium, calcium, copper, zinc, and selenium levels in the blood samples of children with chronic fluorosis were lower than the reference value. The children had higher blood TBARS levels, while the acyl hydroperoxide levels were non-significantly increased in comparison with healthy children living in the non-fluorosis area. Additionally, the bromine level was correlated positively with the selenium level and acyl hydroperoxides. However, more studies are needed to clarify the relationship between blood mineral status, oxidative stress biomarkers, and chronic fluorosis.