Transfer of Hazardous Chemicals from Ingested Plastics to Higher-Trophic-Level Organisms

Abstract

Field observations of seabirds and whales indicate transfer of chemicals from ingested plastics to the tissue of organisms which have ingested the plastics. To determine the significance of plastic-mediated exposure of chemicals, it should be compared with natural prey-mediated exposure. In case where background pollution is high, plastic-mediated exposure is relatively smaller. However, in remote ecosystem with trace background pollution where marine plastics bring larger amounts of pollutants, plastic-medicated exposure could be significant. In case of additives that are bio-diluted such as BDE209, ingested plastics could be major exposure sources. Leaching experiment using stomach oil indicates that lipophilic nature of digestive fluid is key to facilitate the leaching of hydrophobic chemicals from the plastics and, consequently, the transfer and accumulation of the chemicals in the tissue to biota which have ingested the plastics. Understanding the nature of digestive fluid and biological dynamics of the digestive system is important.