Nitrates in Turkish waters: sources, mechanisms, impacts, and mitigation

Abstract

Intensive technological developments, rapid population growth, unplanned urbanization, and excessive use of nitrogen fertilizers have caused water resources to be contaminated substantially by nitrates in Turkey as well as across the world as evidenced by the accumulated scienti c information. The information should be evaluated to draw a nationwide attention to the problem. The aim of this review article was to highlight the importance of nitrate (NO 3 ) contamination and to discuss the measures to be taken to mitigate nitrate contamination across the nation. Signi cant number of the peer-reviewed scienti c articles were examined to identify anthropogenic sources, spatial and temporal variability, and contamination mechanisms of the nitrate contamination of the water resources across Turkey. Agriculture, especially chemical fertilizers used in irrigated agriculture, was the most important source of nitrates in groundwater. Also, the industrial and domestic discharges from highly populated and industrialized regions were signi cant sources of nitrates in the water resources. The most severe and widespread nitrate contamination occurred in the regions where intensive agriculture, industrial development, and rapid urbanization coincided. Drinking waters have been exposed to a signi cant nitrate contamination in many regions across the nation, raising a serious health concern to the people. A well-developed action plan is urgent for mitigating nitrate contamination in Turkish waters to avoid further degradation of those valuable resources.

Potential Health Risk Assessment for Nitrate Contamination in the Groundwater of Mersin Province, Türkiye

“…Maximum groundwater nitrate concentrations were consistently measured in between Tarsus and Karaduvar regions in 2020 (Table 3). Intensive irrigation in agriculture, rapid urbanization and the terrestrial inputs from the domestic wastewater and industrial discharges have led to nitrate pollution in surface waters and groundwater in Mersin Province (Özbay et al, 2012;Akçay et al, 2022;Akçay, 2023;Akçay et al, 2023;Erşahin & Bilgili, 2023;Türkeri et al, 2023). Study findings indicated that highest concentrations were consistently measured in the regions where human-induced pressures are very intense (Güler et al, 2012;Erşahin & Bilgili, 2023).…”

“…Study findings indicated that the highest groundwater nitrate concentrations were consistently measured in these regions due to the anthropogenic pressures caused to nitrate contamination that would lead to potential health hazards for the people that use groundwater of these nitrate contaminated regions (Table 1, Figure 2). Anthropogenic perturbations such as the increase in population and hence domestic sewage, and the excess use of chemical fertilizer in the agriculture highly enhances nitrate pollution in the groundwater that can cause to health risks for people who use groundwater for consumption (Güler et al, 2012;Li et al, 2012;Wu et al, 2012;Wu & Sun, 2016;Adimalla, 2020;Erşahin & Bilgili, 2023). Previous studies performed in the groundwater in Mersin Province showed an apparent nitrate pollution due to intensive irrigation in agriculture and industrial activities as well as rapid urbanization in Mersin Province have led to nitrate pollution in groundwater in Mersin Province (Erşahin & Bilgili, 2023).…”

“…Anthropogenic perturbations such as the increase in population and hence domestic sewage, and the excess use of chemical fertilizer in the agriculture highly enhances nitrate pollution in the groundwater that can cause to health risks for people who use groundwater for consumption (Güler et al, 2012;Li et al, 2012;Wu et al, 2012;Wu & Sun, 2016;Adimalla, 2020;Erşahin & Bilgili, 2023). Previous studies performed in the groundwater in Mersin Province showed an apparent nitrate pollution due to intensive irrigation in agriculture and industrial activities as well as rapid urbanization in Mersin Province have led to nitrate pollution in groundwater in Mersin Province (Erşahin & Bilgili, 2023). In a recent study performed by Moeini and Azhdarpoor (2021), a sensitivity analysis was carried out to determine the most effective parameter in health risk assessment and it was shown that decreasing the nitrate concentrations can reduce the level of health risk for nitrate contamination by the reduction of HQ values for all age groups.…”

“…It was reported by the World Health Organization that approximately a quarter of mortalities have been caused by environmental risk factor (Radfard et al, 2019). Although water sources have been contaminated by nitrate and nitrite in Türkiye (Erşahin & Bilgili, 2023), their adverse effects on human health in drinking water are currently unclear (Picetti et al, 2022). This study, therefore, aimed to determine potential health risk assessment for nitrate pollution in groundwater of Mersin Province.…”

“…Though groundwater is the most significant natural water resources for human being, its quality is deteriorating due to the anthropogenic perturbations posing health risks for people who use groundwater for consumption (Li et al, 2012;Wu et al, 2012;Wu & Sun, 2016;Adimalla, 2020). For example, the increase in population growth, intense urbanization, intensive technological developments and excessive use of nitrogencontaining fertilizers have led to nitrate contamination in Türkiye (Erşahin & Bilgili, 2023).…”