Researchers recently discovered human-made pollutants in the Peru–Chile Trench, also known as the Atacama Trench, an oceanic trench in the eastern Pacific Ocean. The presence of chemical compounds polychlorinated biphenyls (PCBs) at depths of 8,000 meters highlights the far-reaching impact of pollution on Earth.
The presence of chemical compounds polychlorinated biphenyls (PCBs) at depths of 8,000 meters highlights the far-reaching impact of pollution on Earth.
PCBs were mass-produced from the 1930s to the 1970s for use in electrical equipment, paints, coolants, and more. Their detrimental effects on marine life led to a near-global ban in the mid-1970s.
However, PCBs persist in the environment as they take decades to break down, traveling long distances and spreading far from their original locations.
The study analyzed seafloor samples from the Atacama Trench, which extends for almost 6,000km along the South American coast. PCBs were found in all samples taken from depths between 2,500m and 8,085m. Approximately 60% of PCBs released during the 20th century are stored in deep ocean mud.
The Atacama Trench acts like a funnel, collecting dead plants and animals, including pollutants like PCBs. The discovery demonstrates the extent of humanity’s impact on the environment.