EDUCATION UGC NET
ENVIRONMENTAL STUDIES
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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1.5 mg/L
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2.0 mg/L
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2.5 mg/L
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3.0 mg/L
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Detailed explanation-1: -The World Health Organization recommended limit of fluoride in drinking water is 1.5 mg F(-) L(-1), which is also the upper limit for fluoride in drinking water for several other countries such as Canada, China, India, Australia, and the European Union.
Detailed explanation-2: -The current enforceable drinking water standard for fluoride is 4.0 mg/L. This is the maximum amount that is allowed in water from public water systems, also called the Maximum Contaminant Level (MCL).
Detailed explanation-3: -Fluoride levels higher than 1.5 mg/L may cause white spots to form on tooth enamel (called dental fluorosis) in children up to the age of 8.
Detailed explanation-4: -The drinking standards laid down by the WHO are 250 mg/L of sulfates and the maximum admissible concentration can reach 400 mg/L.