Which of the following describes the unintended introduction of substances that may include pesticides?

The term that describes the unintended introduction of substances, including pesticides, is contamination. This involves the presence of a harmful substance (in this case, pesticides) in an environment where it is not intended to be, and it can adversely affect the ecological balance, human health, and food safety. Contamination highlights the unintentional and usually undesirable incorporation of chemicals or pollutants, emphasizing the risks they pose when they infiltrate spaces or products that should be free from such substances.

In contrast to contamination, infestation typically refers to the presence of pests or insects in an area, which does not directly deal with chemical substances. Pollution more broadly encompasses the introduction of harmful materials into the environment, but it is often used in relation to air, water, or soil degradation due to multiple sources and not specifically focused on chemical residues like pesticides. Exposure indicates the condition of being subject to a substance, but it does not capture the concept of the unintended introduction of said substances into an environment. Therefore, contamination is the most precise term for this scenario.