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Polychlorobiphenyls in North Atlantic ocean water
Science (New York, N.Y.)
|May 11, 1973
Summary
Polychlorobiphenyls (PCB) levels in the North Atlantic average 20 parts per trillion, totaling an estimated 20,000 metric tons in the upper water column. Concentrations in the Sargasso Sea were found to be lower than in the northern Atlantic.
Area of Science:
- Environmental Chemistry
- Oceanography
- Marine Pollution
Background:
- Polychlorobiphenyls (PCBs) are persistent organic pollutants with known environmental and health risks.
- Understanding PCB distribution in marine environments is crucial for assessing ecological impacts.
- The North Atlantic Ocean is a significant global marine ecosystem potentially impacted by widespread pollutants.
Purpose of the Study:
- To quantify PCB concentrations in the North Atlantic water column.
- To estimate the total mass of PCBs in the upper 200 meters of the North Atlantic.
- To compare PCB levels between the Sargasso Sea and the northern North Atlantic.
Main Methods:
- Water samples were collected at the surface and various depths across the North Atlantic (26-63 degrees N).
- Concentrations of PCBs were measured using established analytical techniques.
- Geographical variations in PCB levels were analyzed, including comparisons with the Sargasso Sea.
Main Results:
- Average PCB concentrations in the North Atlantic surface water were approximately 20 parts per trillion.
- An estimated 2 x 10(4) metric tons of PCBs are present in the upper 200 meters of the North Atlantic.
- Surface water PCB concentrations in the Sargasso Sea were found to be lower compared to the northern North Atlantic.
Conclusions:
- The North Atlantic water column holds a substantial estimated mass of PCBs.
- Geographical variations in PCB concentrations exist within the North Atlantic, with lower levels observed in the Sargasso Sea.
- These findings highlight the pervasive nature of PCB contamination in major ocean basins.