Which trophic level is most susceptible to biomagnification of POPs?

Which trophic level is most susceptible to biomagnification of POPs?

• A. Primary producers
• B. Primary consumers
• C. Secondary consumers
• D. Tertiary consumers

Answer: (D)

Biomagnification happens because contaminants that are persistent and fat-loving build up in organisms and are passed on through the food chain. Persistent organic pollutants don’t break down quickly, and they tend to accumulate in fatty tissues. When a predator eats contaminated prey, it takes in those pollutants, and because the predator may live longer and eat many prey over time, the accumulated amount increases. Each step up the food chain concentrates higher levels of these chemicals, so the top predators end up with the greatest loads. That’s why tertiary consumers—the top of the food chain—are the most susceptible to biomagnification of POPs. For context, this pattern is why some birds of prey exposed to DDT show serious health effects, and why marine mammals can accumulate high PCB levels.

Biomagnification happens because contaminants that are persistent and fat-loving build up in organisms and are passed on through the food chain. Persistent organic pollutants don’t break down quickly, and they tend to accumulate in fatty tissues. When a predator eats contaminated prey, it takes in those pollutants, and because the predator may live longer and eat many prey over time, the accumulated amount increases. Each step up the food chain concentrates higher levels of these chemicals, so the top predators end up with the greatest loads. That’s why tertiary consumers—the top of the food chain—are the most susceptible to biomagnification of POPs. For context, this pattern is why some birds of prey exposed to DDT show serious health effects, and why marine mammals can accumulate high PCB levels.