Abstract
Nitrates in drinking water has been associated to adverse health effects, including changes in glucose and lipid levels, thyroid hormone imbalance and adverse reproductive effects. We analyzed metabolic and thyroid hormone alterations and genotoxic damage in women with chronic exposure to nitrates in drinking water. The concentration of nitrates in drinking water was quantified and according to this parameter, participants were divided into three exposure scenarios. Blood and urine samples were collected from 420 women living in Durango, Mexico and biomarkers were determined. We found nitrates concentrations in drinking water above the permissible limit (>50 mg/L), and an increase in the percentage of methemoglobin (p=0.0001), nitrite in blood plasma and urine (p=0.0001), glucose (p=0.0001), total cholesterol (p=0.001), LDL (p=0.001) and triglycerides (p=0.0001). We also found alterations in TSH (p=0.01), fT3 (p=0.0003), T4T (p=0.01) and fT4 (p=0.0004) hormones. Frequency of subclinical hypothyroidism was 8.33%; differences in FOXE1 (rs965513, rs1867277) genotypes distribution were found and both polymorphisms were associated with a decrease in TSH. A high percentage of micronucleus in binucleate lymphocyte cells was found (35%, p=0.0001). In conclusion, the chronic exposure to nitrates in water for human consumption caused metabolic and hormonal alterations and genotoxic damage in women.
Highlights
Nitrate is a natural compound present in soil, air and water, which forms part of the nitrogen cycle
There is a distinction between low, medium and high exposure, there is no consensus about the ranges and doses in each group, a strategy is to stratify according to the concentrations found in the specific study, in order to observe the exposure gradient
Some of these values were higher than the 44.3–50 mg/L permissible limit of nitrates established by NOM–127– SSA–1–1994 and World Health Organization (WHO) (2011)
Summary
Nitrate is a natural compound present in soil, air and water, which forms part of the nitrogen cycle. Nitrogen and its stable forms are essential components of many molecules; it is considered a potential health hazard due to the generation of N–nitroso compounds, which are pro– oxidants of several biomolecules. The pollution caused by nitrates is mainly attributed to certain industrial activities, as well as to the use of fertilizers in agriculture. Intake of nitrates among the human population occurs mainly through consumption of vegetables and processed foods, in addition to contaminated water. Water contamination occurs through leaching due the excessive use of fertilizers and pesticides that pollute the soil, which later reach the aquifers, contaminating. Universidad Juárez del Estado de Durango, Facultad de Ciencias Químicas, Laboratorio de Biología Celular y Molecular, Av. Artículo, 123, Fracc., Filadelfia, C.P. 35010. E-mail: rebecapms@ ujed.mx the water that supplies the network for public use (Ombreta et al, 2018)
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
