What is the maximum limit of selenium in soil?Select one:a.1 μg/kgb.0.5 μg/kgc.5 μg/kgd.0.3 μg/kg

To determine the correct answer, we need to refer to environmental standards and guidelines regarding the maximum allowable limits of selenium in soil. Here's the analysis:

Understanding Selenium Limits

Selenium is a trace element that can be toxic to plants and animals in high concentrations. Various environmental agencies set guidelines on the acceptable levels of selenium in soil to ensure safety.

Reference for Standards

According to the environmental guidelines, the maximum allowable concentration of selenium in soil can vary, but commonly cited values are generally in the range of 0.5 μg/kg to 5 μg/kg, depending on the specific regulations of different regions.

Evaluating Options

1. 1 μg/kg - This is a moderate level that may be acceptable in certain contexts.
2. 0.5 μg/kg - This is often cited as a conservative limit to avoid toxicity.
3. 5 μg/kg - This is towards the higher end of the spectrum and may not be acceptable in many regulatory frameworks.
4. 0.3 μg/kg - Generally lower than the typical standards found in regulation.

Conclusion

In most regulatory contexts and scientific literature, 0.5 μg/kg is frequently referenced as a standard limit for selenium in soil. Thus, it appears to be the most widely accepted figure for ensuring safety and minimizing toxic effects.

Final Answer

b. 0.5 μg/kg is the maximum limit of selenium in soil according to common environmental standards.