Which of the following best describes PCBs?

Polychlorinated biphenyls (PCBs) are best described as persistent organic pollutants. This classification highlights their stability in the environment, resistance to degradation, and tendency to bioaccumulate in the food chain. PCBs do not break down easily, which means they can remain in the environment for long periods, leading to potential exposure to wildlife and humans.

Understanding PCBs as persistent organic pollutants is crucial for environmental health, as their long-lasting presence poses multiple health risks, including potential endocrine disruption and cancer. They can accumulate in fat tissues and tend to be found in higher concentrations in animals higher up in the food chain, impacting ecosystem health and human safety.

Other descriptions, such as being highly soluble in water, quickly degraded, or non-toxic to humans, do not accurately fit PCBs. In fact, PCBs are known for their low water solubility, resistance to microbial degradation, and toxicity, which reinforce why option C is the most accurate characterization among the choices provided.