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How did DDT move through food chains and affect birds?

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organohalogen compound Vinyl chloride is an organohalogen compound that has important industrial applications. When treated with certain catalysts, vinyl chloride monomers undergo polymerization and form the larger compound known as polyvinyl chloride, or PVC. PVC is used in the manufacture of numerous products, including packaging films and water pipes.

DDT is a persistent organohalogen compound that does not break down easily in the environment, allowing it to linger in soils and water for years. Because the chemical dissolves readily in fats, it accumulates in the tissues of living organisms, a process known as bioaccumulation.123

As contaminated insects and other small organisms are consumed by predators, the concentration of DDT increases as it moves up the food chain, a phenomenon called biomagnification. This process leads to high levels of the pesticide in the tissues of top predators.123

Birds, particularly birds of prey and songbirds, were especially vulnerable to these accumulated levels. DDT exposure caused significant eggshell thinning, which reduced egg viability and led to fewer hatchlings. This reproductive failure caused severe population declines in species such as eagles, falcons, and pelicans, a crisis famously highlighted in Rachel Carson's book Silent Spring.2415