In the general sense of the word, pollution is a degradation of the environment through the introduction into the air, water or soil of materials not naturally present in that environment.

Pollution generates imbalances. By causing a more or less irreversible disruption of ecosystems, the polluting phenomenon mainly results in the migration or extinction of endemic living species, which are all too often unable to adapt to their new biophysical environment. On a larger scale, pollution can have a direct impact on human health and the biosphere, as illustrated by the process of global warming, which causes profound climatological changes and leads to the appearance of previously unknown diseases.

All human activities are potentially likely to cause accidental or chronic pollution. Commercial or pleasure boats, but also offshore oil exploration or exploitation platforms, submarine gravel pits, dredging or construction sites and aquaculture installations are, without exception, the source of polluting discharges.