What does it mean for a substance to be hazardous to the environment?

A substance is considered hazardous to the environment when it poses a risk to ecological health. This encompasses a variety of scenarios where chemicals or materials can contaminate soil, water, or air, thereby adversely affecting wildlife, plants, and overall ecosystem function. Such substances can disrupt the balance of natural systems and lead to long-term damage, which may include toxic effects on organisms, bioaccumulation in food chains, and degradation of habitats.

In contrast, the other options do not reflect the essence of environmental hazard. Biodegradable materials (first choice) break down naturally and are generally viewed as less harmful. Enhancing soil quality (third choice) suggests a positive impact on the environment, while non-toxic substances (last choice) are by definition not harmful. Therefore, the understanding of what constitutes environmental hazards revolves around the potential risks and negative implications for ecological health.