Which process is a significant source of heavy metals in the environment?

Fossil fuel combustion is a significant source of heavy metals in the environment due to the release of pollutants from burning coal, oil, and natural gas. During combustion, various impurities in fossil fuels, including heavy metals like mercury, lead, and cadmium, can be emitted into the atmosphere or settle as particulates. These metals can then contaminate air, soil, and water, leading to harmful environmental and health effects.

In contrast, renewable energy production, nuclear power generation, and solar energy usage generally have lower emissions of heavy metals. Renewable energy sources like wind and solar power do not involve the combustion of fossil fuels, significantly reducing the associated risks of heavy metal contamination. Similarly, while nuclear power generation does produce waste products, they are different in nature compared to the byproducts of fossil fuel combustion, and nuclear plants have stringent controls to minimize environmental impacts. Hence, fossil fuel combustion stands out as the primary contributor to environmental heavy metal pollution.