Which contaminant has a Maximum Contaminant Level (MCL) of 4.0 mg/L?

Which contaminant has a Maximum Contaminant Level (MCL) of 4.0 mg/L?

• A. Arsenic
• B. Nitrate
• C. Nitrite
• D. Fluoride

Answer: (D)

The contaminant that has a Maximum Contaminant Level (MCL) of 4.0 mg/L is fluoride. This standard is established to protect public health by limiting the amount of fluoride in drinking water because excessive fluoride can lead to adverse health effects, including dental and skeletal fluorosis. Fluoride is commonly added to drinking water for its benefits in preventing dental cavities. However, maintaining the balance is crucial, as high levels can pose risks. The MCL of 4.0 mg/L is set to ensure that fluoride levels in water supplies are safe for consumption while still permitting the beneficial effects that fluoride can provide in preventing tooth decay. Arsenic, nitrate, and nitrite all have different MCLs due to their unique health risks. For example, arsenic has a much lower MCL of 0.01 mg/L due to its carcinogenic properties, while nitrate and nitrite are regulated at different levels (10 mg/L for nitrate and 1 mg/L for nitrite) based on their potential to cause methemoglobinemia, or "blue baby syndrome," in infants. These comparisons highlight the importance of adhering to established MCLs to protect public health from various contaminants.

The contaminant that has a Maximum Contaminant Level (MCL) of 4.0 mg/L is fluoride. This standard is established to protect public health by limiting the amount of fluoride in drinking water because excessive fluoride can lead to adverse health effects, including dental and skeletal fluorosis.

Fluoride is commonly added to drinking water for its benefits in preventing dental cavities. However, maintaining the balance is crucial, as high levels can pose risks. The MCL of 4.0 mg/L is set to ensure that fluoride levels in water supplies are safe for consumption while still permitting the beneficial effects that fluoride can provide in preventing tooth decay.

Arsenic, nitrate, and nitrite all have different MCLs due to their unique health risks. For example, arsenic has a much lower MCL of 0.01 mg/L due to its carcinogenic properties, while nitrate and nitrite are regulated at different levels (10 mg/L for nitrate and 1 mg/L for nitrite) based on their potential to cause methemoglobinemia, or "blue baby syndrome," in infants. These comparisons highlight the importance of adhering to established MCLs to protect public health from various contaminants.