NGRI scientists warned that infants and children are at higher risk owing to nitrate ingestion through drinking water.

Researchers said fertilizer leachate is seeping into aquifers and a majority of groundwater samples analysed by them were unfit for consumption. NGRI scientist Rama Mohan Kurakalva said people who are utilising the water in Mahbubnagar and other districts of upper Krishna river basin are at risk. “We did studies on water quality in pre-monsoon and post-monsoon to find out variation. We found the groundwater nitrate-rich and fluoride-rich. We did a risk assessment study based on US Environmental Protection Agency guidelines,” he said.

The study was conducted in two seasons to confirm consistency of contamination and to measure increase or decrease in nitrate and fluoride content. Researchers collected a total of 116 groundwater samples from an intensive agricultural region of Wanaparthy area in Mahbubnagar to evaluate seasonal variations.

As per the water quality index, 36.2 per cent samples in pre-monsoon season and 60.3 per cent in post-monsoon fell in poor to unfit category (drinking water). “The hazard quotient values of nitrate were greater for infants and children. They are in more danger of non-carcinogenic ingestion of nitrate contaminated groundwater than adults,” the study said.

Rama Mohan blamed indiscriminate use of fertilizers in agriculture production for high nitrate content. “Usually, nitrate content goes up in urban sewers contaminating the area or sees a spike due to agricultural fertilizer usage. There are no industries and no urban sewerage in the study area,” he explained in the study which was published in Science Direct Ecotoxicology and Environmental Safety Journal.