What is the term for the introduction of harmful substances into an ecosystem?

The correct term for the introduction of harmful substances into an ecosystem is pollution. Pollution occurs when pollutants—such as chemicals, waste products, or foreign substances—are added to the environment, leading to negative effects on the health of ecosystems, wildlife, and human populations. This can happen through various means, including industrial discharges, agricultural runoff, and plastic waste. The effects of pollution can be far-reaching, often causing alterations in habitats, declines in biodiversity, and disruptions in ecological processes.

Conservation refers to the protection and management of natural resources, aiming to preserve biodiversity and maintain ecosystems. Contamination generally implies the presence of unwanted or harmful substances but is typically used in a more specific sense, such as soil or water contamination, rather than describing the broader concept of pollution. Restoration pertains to the process of returning a disturbed ecosystem to its original state, which contrasts with the introduction of harmful substances.