We reviewed the physical, chemical and biological behaviors of microplastics in the marine environment.

Mechanisms (sedimentation, shore deposition, nanofragmentation, and ingestion) that remove floating plastics are at play.

Biodegradation of plastics is characterized by formation of biofim, weight loss and visual pits.

Risks associated with ingested plastics come from the material itself and the sorbed pollutants.

Areas for future research that deserve further attentions on this growing issue are proposed.