Nalgonda technique is related to______ content in water

Ans. A. Fluorine. (Ref. Park's Textbook of PSM 22nd/pg.598)Nalgonda technique is used for defluoridation of water. The technique is devised by National Environment EngineeringResearch Institute, Nagpur. It involves addition of lime & alum in sequence followed by flocculation, sedimentation and filtration.Endemic Flurosis:# The permissible concentration of fluorides in drinking water is 0.5 to 0.8 mg/L.# Where drinking water contains excessive amounts of fluorine (3-5mg/L), endemic Flurosis has been observed.# Certain parts of the country, e.g., Andhra Pradesh, Punjab, Haryana, Karnataka, Kerala and TN are known for it.# Dental Flurosis: Ingested during the years of tooth calcification essentially during the first 7 years of life by "mottling of dental enamel", which has been reported at levels above 1.5 mg/1 intake. Mottling is best seen on the incisors of the upper jaw.# Skeletal Flurosis/ Genu valgum: Lifetime daily intake of 3.0-6.0 mg/1 or more.# Prevention: Changing the water source.# The use of fluoride toothpaste in areas of endemic flurosis is not recom for children upto 6 yrs of age.# Nalgonda technique for defluoridation of water.