Session 2: Assessing the real concentrations of microplastic and their actual effects on marine biota

Hosts: Lukas Novaes Tump1, Mel Constant2,3

  1. University of Oldenburg, Germany
  2. LGCgE, IMT Lille Douai, France
  3. LASIR, Unversité Lille 1, France

Microplastics were discovered almost everywhere we searched for them, including groundwater, deep sea, atmospheric fallout and even pristine places far from human activities1–4. Possible threats for marine life include physical injury though ingestion or toxicological effect of additives and adsorbed pollutants5,6. But as a well-established framework for this rather new field of research is still missing, many questions are yet to be answered. While the amount of microplastic is predicted to double by 2030 in some parts of the ocean7, guidelines and profound methodologies are urgently needed8.

In this session we want to address two major difficulties in microplastic research:

  1. The methodology to assess microplastic in the environment as well as their concentrations differ significantly between studies. In this session we want to discuss how to measure the pollution in the environment from source to sink.
  2. Similarly, the assessment of microplastic effects encounter methodological issues. Effects caused by the high particle loads used in microplastic research have probably been misinterpreted as plastic effects, due to a misappropriate or inadequate comparison. Indeed, The majority of studies compare the performance of organisms exposed to microplastic to organisms that were not exposed to any kind of particle. However, negative effects caused by high natural particle concentrations have been proven manifold. To avoid this problem a new experimental approach was designed, where microplastics were compared to a fitting natural particle of the same size and concentration, instead of a particle less reference group.

We also propose to open the discussion on possible solutions for the plastic problem: Are there ways to remove the pollution?

To conclude, we would like to host a session to discuss the methods and outcomes of our studies with experts and young researchers interested in the field of microplastic. We intend to create room for an open dialogue and constructive critique to pave the way for the future generation of microplastic researchers.

References

  1. Bergmann, M. et al. High Quantities of Microplastic in Arctic Deep-Sea Sediments from the HAUSGARTEN Observatory. Environ. Sci. Technol. 51, 11000–11010 (2017).
  2. Panno, S. V. et al. Microplastic Contamination in Karst Groundwater Systems. Groundwater 57, 189–196 (2019).
  3. Dris, R., Gasperi, J., Saad, M., Mirande, C. & Tassin, B. Synthetic fibers in atmospheric fallout: A source of microplastics in the environment? Mar. Pollut. Bull. 104, 290–293 (2016).
  4. Allen, S. et al. Atmospheric transport and deposition of microplastics in a remote mountain catchment. Nat. Geosci. 12, 339–344 (2019).
  5. Wright, S. L., Thompson, R. C. & Galloway, T. S. The physical impacts of microplastics on marine organisms: A review. Environ. Pollut. 178, 483–492 (2013).
  6. Rochman, C. M. The Complex Mixture, Fate and Toxicity of Chemicals Associated with Plastic Debris in the Marine Environment. in Marine Anthropogenic Litter (eds. Bergmann, M., Gutow, L. & Klages, M.) 117–140 (Springer International Publishing, 2015). doi:10.1007/978-3-319-16510-3_5.
  7. Isobe, A., Iwasaki, S., Uchida, K. & Tokai, T. Abundance of non-conservative microplastics in the upper ocean from 1957 to 2066. Nat Commun 10, 1–13 (2019).
  8. Cadiou, J.-F. et al. Lessons Learned from an Intercalibration Exercise on the Quantification and Characterisation of Microplastic Particles in Sediment and Water Samples. Mar. Pollut. Bull. 154, 111097 (2020)