Pollution spares nothing, it spreads everywhere. Even the almost inaccessible world of underwater depths is a victim of pollution. This is what has just been discovered by a team of British scientists, and what the journal Nature Ecology has just revealed on 13 January. The scientists probed, using a submarine robot equipped with traps, two deep pits:
- – Marianne Pit, located in the Pacific Ocean, between Australia and Japan, with a depth of 10,994 meters.
- – The Kermadec pit, north of New Zealand, which descends to 10,050 meters.
Alan Jamieson of the Institute of Biological and Environmental Sciences at the University of Aberdeen in Scotland and his team have come up with amphipodes, small crustaceans that only measure one centimeter. By analyzing their organism, they discovered an impressive level of toxic substances, prohibited since the late 1970s because of their toxicity, PCBs and PBDEs. The former were used as insulation in transformers, and the latter as flame retardants for plastics and textiles.
All the species studied, without exception, were contaminated and the concentration of these substances is impressive! The PCB concentration is 50 times higher than that of crustaceans living in the Liao River, China’s most polluted aquatic environment. The presence of these pollutants does not surprise scientists, the industry has provided 1.3 million tons of PCBs, and as they explain “these pollutants are invulnerable to natural degradation and stays in the environment for decades. “
Responsibility for plastic
Some may argue that many ocean anti pollution projects are underway. One could quote the fantastic project Ocean Cleanup by Boyan Slat. However, most of the solutions proposed only solve the surface problem. In other words, although some projects recently launched will solve the problem of the plastics continents in the years to come, the question of the pollution of the ocean floor remains unanswered at the present time.
But how can these substances, which infiltrate the food chain, contaminate the underwater depths? Those responsible would be the plastic debris and the dead bodies of animals that sink into the seabed, and which feed on the amphipods, true garbage collectors of the oceans. These small fleas of water are in their turn devoured, and thus pollution touches the entire food chain of the underwater depths.
The report on the high pollution of the sea floor attests to “the devastating and long-term impact that humanity has on the planet” explains Alan Jamieson. The next step for research will be to determine the long-term consequences of pollution on marine wildlife. But what we can already say is that the rejections of civilization do not end up poisoning our planet!