Dichloro-diphenyl-trichloroethane, commonly called DDT, was a widely used pesticide in the United States from 1943 to the 1970s. By 1972, increasing awareness of the harmful effects on human health and wildlife resulted in the pesticide being banned from use in the United States. However, the environmental impact of DDT did not end when the ban was put into effect. Due to its chemical properties, DDT is known to remain in soil and animal tissues for 2–15 years and can pollute aquatic ecosystems for up to 150 years. Food contamination through all levels of the food chain continues to be a focus of research. The image shows the concentration of DDT found at the different trophic levels in ecosystems impacted by the pesticide.

Circular graphic showing the concentration of DDT at the different trophic levels. Algae show 0.04 ppm, zooplankton shows 0.23 ppm, small fish show 2.07 ppm, large fish show 7.36 ppm, and humans show 13.55 ppm.

Based on the information provided, what predictions can be made about the impacts of DDT on the ecosystem?

Humans and animals at the top of the food chain would suffer the greatest impact because the pesticide builds up at each tropic level, increasing the toxicity.
Aquatic producers at the base on the food chain would suffer the greatest impact because the pesticide can remain in aquatic systems for long periods.
Land mammals at the top of food chain would suffer the least impact because the pesticide remains in soil for a short amount of time.
Small fish in the middle of the food chain would suffer the least impact because the pesticide has not built up enough to harm them in any way.