The maximum prescribed concentration of cadmium in drinking water in ppm is

Options

A. 0.005
B. 3
C. 2
D. 5

Answer

To determine the maximum prescribed concentration of cadmium in drinking water in parts per million (ppm), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Maximum Contaminant Level (MCL)**:
The maximum concentration of cadmium in drinking water is established by the US Environmental Protection Agency (US EPA). According to the information provided, this concentration is 0.005 mg per liter.

2. **Understand the Relationship Between mg/L and ppm**:
In terms of drinking water, 1 mg/L is equivalent to 1 ppm. This is because 1 liter of water is approximately equal to 1,000 grams, and thus 1 mg in 1 liter corresponds to 1 part in 1 million parts.

3. **Convert mg/L to ppm**:
Since the concentration of cadmium is given as 0.005 mg/L, we can directly state that:
\[ \text{Concentration in ppm} = 0.005 \text{ mg/L} = 0.005 \text{ ppm} \]

4. **Select the Correct Answer**:
Based on the conversion, the maximum prescribed concentration of cadmium in drinking water is 0.005 ppm. If this is one of the options provided in the question, it is the correct answer.

### Final Answer:
The maximum prescribed concentration of cadmium in drinking water is **0.005 ppm**.

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