Regulations restricting land application of metals exist primarily to keep metals out of the human food chain.

Regulations restricting land application of metals exist primarily to keep metals out of the human food chain.

• A. To keep metals out of human food chain
• B. To prevent soil erosion
• C. To reduce irrigation water use
• D. To increase soil fertility

Answer: (A)

The main idea is to protect human health by preventing metals from entering the food chain. Metals added to soil can accumulate over time and be taken up by crops or leach into groundwater, so long-term exposure through food becomes a real risk. Even metals that are needed in tiny amounts can be toxic at higher levels, so regulations set limits to keep tissue concentrations at safe levels. While metals in land applications can interplay with soil health and other issues, the primary aim of these rules is to minimize dietary exposure and protect people, not to address erosion, water use, or soil fertility. That focus on preventing metals from reaching the food chain is why this option is the best choice.

The main idea is to protect human health by preventing metals from entering the food chain. Metals added to soil can accumulate over time and be taken up by crops or leach into groundwater, so long-term exposure through food becomes a real risk. Even metals that are needed in tiny amounts can be toxic at higher levels, so regulations set limits to keep tissue concentrations at safe levels. While metals in land applications can interplay with soil health and other issues, the primary aim of these rules is to minimize dietary exposure and protect people, not to address erosion, water use, or soil fertility. That focus on preventing metals from reaching the food chain is why this option is the best choice.