Globally, marine animals are exposed to plastic particles that are ingested at all levels of the food web; from zooplanktion, mussles and worms to fish, birds and marine mammals. Animals ingest plastics by mistaking them for food or taking them up through their gills. Experiments have shown that microplastics can also be transported upwards in the food web from one species to another, for example, from mussles to shore crabs. It is likely that microplastics are also transferred between species higher up in the food web.

To date, most experimental studies aimed to establish whether microplastic particles are harmful have been carried out using higher concentrations than those found in the marine environment. In such experiments, it has been shown that high concentrations of microplastics impair zooplankton survival, food intake, and reproduction. But harmful effects have also been observed in experiments using lower concentrations, that are more similar to concentrations found in the marine environment. This gives cause for concern of harmful effects of microplastics on marine organisms.

Policy recommendation

  • Seek to reduce the discharge of microplastics from both land- and sea-based sources.
  • Standardise the difference between compostable, degradable, and biodegradable plastics. Plastics that are industrially compostable may take a long time to break down in the marine environment.
  • Ban microplastics in cosmetics and hygiene products. Microplastics should be banned in rinse-off products, but also in leave-on products where they can be replaced because of their risk of ending up in wastewater from showering and washing clothes.
  • Regulate similar chemicals found in plastics on a group basis instead of one-by-one in order to ensure greater efficiency. In the review of REACH, the chemicals’ decomposition products in the marine environment should be taken into account, because these can also be harmful.
  • Allow the precautionary principle to be paramount in achieving Good Environmental Status in accordance with the Marine Directive. Because plastics and highly persistent chemicals take a very long time to degrade, the problem is largely irreversible once it has been detected.

Read and download:
Policy Brief: Microplastics in marine life (309 Kb)
References: Microplastics in marine life (235 Kb)


Marie Löf
Ecotoxicologist, Baltic Eye, Baltic Sea Centre
+46 (0)8 16 38 55,

Hanna Sjölund
Advocacy and Analysis Officer, Baltic Eye, Baltic Sea Centre
+46 (0)8 16 31 27,