Fluoride level in water shouldbe ____ mEq/L –
**Core Concept**
Fluoride is an essential ion for maintaining dental health, but excessive intake can lead to fluorosis. The optimal level of fluoride in drinking water is crucial for preventing dental caries without causing adverse effects.
**Why the Correct Answer is Right**
The recommended level of fluoride in drinking water is 0.7-1.2 mg/L (milligrams per liter), which translates to 0.12-0.21 mEq/L (milliequivalents per liter). This concentration is sufficient to prevent dental caries while minimizing the risk of fluorosis. The optimal fluoride level is achieved through a balance between the amount of fluoride added to the water supply and the naturally occurring fluoride levels in the water.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because fluoride levels below 0.7 mg/L (0.12 mEq/L) may not be sufficient to prevent dental caries, especially in areas with poor oral hygiene.
**Option B:** This option is incorrect because fluoride levels above 1.2 mg/L (0.21 mEq/L) can lead to severe fluorosis, including dental and skeletal abnormalities.
**Option C:** This option is incorrect because it does not provide a clear or specific guideline for the optimal fluoride level in drinking water.
**Clinical Pearl / High-Yield Fact**
The optimal fluoride level in drinking water is a balance between preventing dental caries and minimizing the risk of fluorosis. This level is achieved through a combination of artificially added fluoride and naturally occurring fluoride in the water supply.
**Correct Answer: C. 1.2 mg/L