Abstract
Micropollutants (MPs) include a wide range of biological disruptors that
can be toxic to wildlife and humans at very low concentrations
(<1 μg/L). These mainly anthropogenic pollutants have been widely
detected in different areas of the planet, including the deep sea, and
have impacts on marine life. Because of this potential toxicity, the
global distribution, quantity, incidence, and potential impacts of
deep-sea MPs were investigated in a systematic review of the literature.
The results showed that MPs have reached different zones of the ocean
and are more frequently reported in the Northern Hemisphere, where
higher concentrations are found. MPs are also concentrated in depths up
to 3000 m, where they are also more frequently studied, but also extend
deeper than 10,000 m. Potentially toxic metals (PTMs), polychlorinated
biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDTs), organotins,
and polycyclic aromatic hydrocarbons (PAHs) were identified as the most
prevalent and widely distributed MPs at ≥200 m depth. PTMs are widely
distributed in the deep sea in high concentrations; aluminum is the most
prevalent up to 3000 m depth, followed by zinc and copper. PCBs,
organotins, hexachlorocyclohexanes (HCHs), PAHs, and phenols were
detected accumulated in both organisms and environmental samples above
legislated thresholds or known toxicity levels. Our assessment indicated
that the deep sea can be considered a sink for MPs.