Borewells may spur fluorosis cases, says study

ALAPPUZHA: Widespread use of borewells in the district could deplete water tables and cause a spurt in fluorosis cases as the presence of fluoride in groundwater is high in Alappuzha and Palakkad districts. People are indiscriminately digging borewells without approval with rains playing truant here. Minerals such as calcium fluoride, apatite, cryolite, and fluorspar are present in the aquifer. A study last year had found that 6,064 children had fluorosis when they tested urine samples of 15,182 children from 114 schools in the district. Arun P.R., a scientist at the Centre for Water Resources Development and Management, Kunnamangalam, says people must be aware that the borewell water has high morbidity associated with dental fluorosis and ensure defluoridate water before drinking.

"There's a stepwise increase in the prevalence of dental fluorosis with a corresponding growth in water fluoride content in different panchayats of the district," he said. "High iron content in borewells and bacteriological contamination in certain areas could worsen the situation. Ferrous sulphate is unstable in groundwater, and it precipitates as insoluble ferric hydroxide, which settles out as rust coloured silt.” The percentage of fluorosis among children has now touched 40 while it was 35.6 in 1997, mainly on account drinking water with high fluoride content.

"Places like Chennithala, where Japan drinking water project runs properly, is less exposed to the defect," says Dr C. O. Rajendrakumar, the nodal officer for Central fluorosis mitigation programme. "The prevalence of dental fluorosis is higher in the urban areas compared to the countryside, and in girls compared to boys."  While the internationally accepted level of fluoride is one particle per molecule (ppm), the level in several places in Alappuzha is 2.5 ppm, considered a toxic dose. The related ailments are skeletal fluorosis, knock-knee, bow leg, spinal issues leading to neurological problems, abdominal discomfort, low birth weight and infertility in males owing to the abnormality in sperms.