Please enable JavaScript.
Coggle requires JavaScript to display documents.
Biomagnification (Employment of DDT (Why DDT was stopped (DDT can…
Biomagnification
Employment of DDT
widely employed as a chemical pesticide in the 1940s and 1950s to control insect-borne diseases like malaria
Its use as an agricultural insecticide led to the complete eradication of malaria in many high socioeconomic world regions
It was less effective in low socioeconomic tropical regions where eradication programs could not be sustained
Why DDT was stopped
DDT can bioaccumulate to toxic levels and poses a significant threat to higher trophic levels (due to biomagnification)
Current interventions for malaria now focus on non-spraying strategies (such as the use of bednets soaked in insecticides)
biomagnification
-
-
Properties
Biomagnification occurs because organisms at higher trophic levels must consume more biomass to meet requirements
Energy transformations are only ~10% efficient, so higher order consumers must eat more to meet energy demands
-
DDT
-
DDT is a chemical pesticide that is sprayed on crops and subsequently washed into waterways at low concentrations
It is fat soluble and is selectively retained within the tissues of an organism instead of being excrete
sprayed on water to eliminate mosquito larvae, it is taken up by algae and passed on to primary consumers
DDT versus Malaria
Arguments for DDT
DDT spraying is an affordable and effective means of killing mosquitos that carry disease (malaria, dengue fever, etc.)
Where the use of DDT has been discontinued, the incidence of malaria and associated deaths have increased
-
-
Arguments against
DDT spraying is associated with adverse health effects in humans (cancer, birth defects, reduced fertility, etc.)
-
DDT is biomagnified in higher order consumers, which has adverse consequences on ecosystems