Answer:
Because it takes a very long time to degrade, in addition to being a general pesticide, that is, it is capable of killing pests, but also killing the fauna and flora of a region.
Explanation:
DDT stands for Dichloro-Diphenyl-Trichloroethane, a powerful and inexpensive pesticide that was widely used during WW2 to combat insect pests.
DDt is highly polluting and dangerous for the environment. This is because it is a generalist pesticide, that is, it does not act only in the extermination of pests, but it manages to kill any and all living organisms in the region where it is applied, which results in the death of the fauna and flora of a region. In addition, DDT spends a long period of time to be degraded and can remain active in nature for up to 30 years, which causes it to accumulate in soil and water, causing pollution and more deaths.