Maximum Permissible Limit for Fluoride in Drinking Water

Fluoride is a naturally occurring mineral found in water sources and is commonly present in drinking water. While fluoride is beneficial for dental health in controlled amounts, excessive consumption can lead to health issues such as dental fluorosis, skeletal fluorosis, and other adverse effects. Therefore, it is important to establish a maximum permissible limit for fluoride in drinking water to ensure the safety and well-being of the public.

Explanation:

The correct answer to the question is option 'B', which states that the maximum permissible limit for fluoride in drinking water is 1.5 mg/l. Here is an explanation of why this limit is considered safe and appropriate:

1. World Health Organization (WHO) Guidelines:
The World Health Organization (WHO) is a global authority on public health and provides guidelines for various aspects of water quality. According to WHO, the recommended maximum permissible limit for fluoride in drinking water is 1.5 mg/l. This guideline is based on extensive research and studies conducted worldwide, taking into account both health benefits and potential risks associated with fluoride consumption.

2. Dental Health Benefits:
Fluoride is known to have dental health benefits, particularly in preventing tooth decay and cavities. However, the concentration of fluoride required to achieve these benefits is relatively low. The WHO guideline of 1.5 mg/l ensures that the population receives the dental health benefits without exceeding the safe limit.

3. Prevention of Adverse Health Effects:
Excessive fluoride consumption can lead to various health issues. Dental fluorosis, a condition characterized by discoloration and enamel damage, is one of the primary concerns. Skeletal fluorosis, which affects the bones and joints, is another severe consequence of high fluoride intake. The 1.5 mg/l limit helps prevent these adverse health effects while still allowing for the benefits of fluoride.

4. Consideration of Vulnerable Groups:
Certain population groups, such as infants, children, and individuals with kidney problems, may be more susceptible to the adverse effects of fluoride. Therefore, setting a lower limit ensures the safety of these vulnerable groups and provides a margin of safety for the entire population.

In conclusion, the maximum permissible limit for fluoride in drinking water is considered to be 1.5 mg/l based on WHO guidelines and extensive research. This limit balances the dental health benefits of fluoride with the prevention of adverse health effects, ensuring the safety and well-being of the public.