Incidences of pollution are recorded in the form of polreps (lien), pollution reports, generally during patrols by spotter planes.

These reports show quite a regular increase in pollution reports (known as “Polrep”) since 1990, the first year for which statistics are available.

POLREPs in mainland France’s surveillance zones from 2000 to 2004

These figures show that the number of confirmed Polreps, having increased from 281 in 2000 to 396 in 2004, now fluctuate around an average of 350 Polreps annually.