How to investigate the presence and influence of microplastics in our estuaries, seas, and oceans? And: what is the role of microbes in breaking down these microplastics? Dr. Linda Amaral-Zettler and dr. Helge Niemann, two top-notch researchers from the Royal Netherlands Institute for Sea Research, are trying to answer these important questions.

Severe damage to food chains in oceans is possibly caused by a relatively unknown, minuscule enemy: microplastics. Floating between the plankton, or hidden in the sediment on the seabed, these small plastic particles (<5 mm) are permeating the marine environment worldwide. Dr. Linda Amaral-Zettler and dr. Helge Niemann of the Royal NIOZ want to know where the enormous amount of plastic has gone that seems to have dissolved in the sea since the fifties of the past century.


Plastic incubator

"There is no vaccine against microplastic pollution in oceans," says Dr. Helge Niemann (1976). The German biogeochemist, who earned a scholarship from the European Research Council (ERC) in 2017 with groundbreaking microbial isotope research, is busy testing his plastic incubator in the field, an ingenious machine that records the effects of microbe families on plastic particles on a nanometer scale. He opted for the Royal NIOZ for its sublime labs and facilities.

“There is no real scientific evidence that plastic can be broken down by marine micro-organisms. I want to prove it. Does plastic fall apart into small particles and dissolve, does the growth of organisms cause the plastic to sink to the ocean floor or is the plastic biodegraded?"


Plastic is not a monolithic giant with one face


Besides Niemann, the MMB research department is also investigating the Plastisphere, the thin layer of life attached to the plastic surface – a prime research topic of the Portuguese-American microbiologist and molecular ecologist Dr. Linda Amaral-Zettler (1968) who joined NIOZ in 2017.

“If we capture microplastic in a net at sea, that does not mean that the plastic comes from the same source, has the same composition or the same age. Plastic is not a monolithic giant, does not have one face. If you look at the water column, you do not see those differences. But they are there. Why do microbes behave so differently? They are in the same cup of water, right? The answer is 'no'! And there is something else. If microbes break down plastic and pathogens or harmful algal species develop in that process, how worried should we be about the transport of these organisms via the sea?"

Like to read the interview of dr. Linda-Amaral Zettler and dr. Helge Niemann on microplastics in the Dutch newspaper NRC (Dutch)? Click here.

For more on the research of dr. Linda Amaral-Zettler at the Royal NIOZ, please check her personal page here.

Please follow this link to the personal page of dr. Helge Niemann at the Royal NIOZ.