Even if we stopped making new plastics now, microplastic pollution would keep increasing for the foreseeable future as larger plastics break down.
A review of 20 years of microplastics research concludes that addressing the pollution problem, which could more than double by 2040, needs regulations that involve the public, social sciences, and natural sciences.
The tiny pieces of plastic are nearly impossible to remove once dispersed, have been found in more than 1300 animal species, and have unknown long-term impacts on human health.
The Science Media Centre asked local experts to comment.
Dr Joel Rindelaub, Senior Lecturer, School of Chemical Sciences, The University of Auckland, comments:
“Everywhere we look, we have found plastics. From remote locations across the globe to the inside our own bodies, plastics have been identified.
“Plastic pollution doesn’t really disappear, it just breaks down into smaller and smaller pieces. While research into environmental plastic pollution is still ongoing, one thing remains clear: plastics are here and they are here to stay.
“Unfortunately, mitigation strategies have not developed to a level that can adequately address environmental plastic pollution. Thus, many researchers believe the most effective strategy to reduce plastic pollution would be to focus on preventative measures, as plastic production is currently increasing exponentially on a global level.
“Preventative strategies, like decreasing plastic production, have encountered several challenges, highlighting the importance of collaborative efforts between industries, governments, and consumers to limit plastic pollution and reduce risk to both humans and the environment.”
Conflict of interest statement: No conflicts of interest.
Professor Sally Gaw, Director of Environmental Science, School of Physical and Chemical Sciences, University of Canterbury, comments:
“Plastics and microplastics are of increasing environmental, human health and public concern due to their pervasiveness and the growing body of evidence of harm from the plastics and the chemicals that they contain.
“These everyday materials with useful properties contribute to the wicked issue of overconsumption that is driving global environmental challenges including biodiversity loss, climate change and pollution.
“The key to solving stemming the release of plastics and ultimately microplastics will be choosing wisely – when is it appropriate or necessary to use plastics and if we need to use plastics what are the best strategies to reduce harm?
“In their review, Thompson et al argue for a multi-disciplinary approach to tackling the global microplastic pollution that integrates science and economics and social strategies. We have done this before to address other persistent and toxic pollutants including organochlorine pesticides and asbestos. We can and must do this again.“
Conflict of interest statement: Professor Sally Gaw researches how products we use in everyday life contribute to environmental pollution.
Associate Professor George Laking, Te Aka Mātauranga Matepukupu Centre for Cancer Research, comments:
“This review of global literature on microplastics is timely. Microplastics are a topic of significant health concern, because they turn out to be all-pervasive yet still quite poorly understood. Our relatively remote location in New Zealand does not make us immune. We have bought into the economy of plastics as enthusiastically as any other affluent nation in the last decades.
“There are implications for all aspects of health, including my own area of cancer. It is an area of health research that New Zealand should be involved in.
“In the meantime, this paper brings together evidence for a precautionary approach in plastics policy. Use of plastics, including so-called biodegradable and recyclable types, should be kept to a minimum. Likewise, a plant-based diet is supported, due to accumulation of microplastics in food chains.
“We have a research team at the University of Auckland that is ready to go with a project on microplastics in the local environment. We hope to come back with our own data in the next months, subject to research funding.“
Conflict of interest statement: No conflicts of interest.
Dr Sebastian Naeher, Lead Scientist of the Organic Geochemistry Laboratory, GNS Science and Microplastic Researcher, comments:
“Microplastics are everywhere – from the most populated, plastic-producing and consuming urban areas – transported by wind, water and through the food chain to the most remote corners of Earth.
“Research has built our knowledge over 20 years, but the biggest challenges are ahead.
“Different research approaches and techniques give different results, which can make it challenging to fully understand micro- and nanoplastics and their lifecycles.
“We see more and more that shape, size and chemistry – which tell us how toxic micro- and nanoplastics are – varies depending on how they’re analysed, so estimates of source and amount can vary.
“Recent research is uncovering the difficulties quantifying health and environmental impacts of micro- and nanoplastics with the tools and techniques available.
“We’re improving our estimates – but the problem is growing and becoming more concerning to humans, wildlife and nature.
“It’s important we act now.“
Conflict of interest statement: No conflicts of interest.
Dr Erin Leitao, Senior Lecturer in Chemistry, The University of Auckland, comments:
“The review article in Science is an excellent summary of the global microplastics pollution crisis. Just like with other pollutants, we are facing the unintended consequences of mass production. Without an immediately obvious threat to our health, or the health of the environment, we continue to manufacture molecules and materials without designing – or at least testing – for their degradation.
“Resistance to degradation is important for designing long-lived materials, but left unmanaged comes at the cost of persistence, accumulation, and leads to significant health concerns.
“The extent of the plastics problem highlights the importance of product stewardship. A cradle-to-grave approach to manufacturing is critical moving forward, alongside eliminating all non-essential uses of plastics.
“In New Zealand, the government has been addressing the plastics problem by banning the distribution and sales of non-essential single-use plastics (from 2022), phasing out hard-to-recycle plastics, and incentivizing research projects to keep plastics out of landfills through funding opportunities such as the Waste Minimisation Fund.
“The increased prevalence of Artificial Intelligence makes it easier than ever to rapidly model how plastic degrades and where it ends up, and such research should be prioritised. Leveraging every modern tool at our disposal will increase our ability to manage the plastics problem. This will require researchers, regulators, and industrial stakeholders across sectors and disciplines to work together.”
Conflict of interest statement: Dr Erin Leitao is part of a NZ-led research team investigating a circular economy for plastics. She was not involved with this paper.
Professor Simon Thrush, Institute of Marine Science, The University of Auckland, comments:
“The new paper in Science is an important summary of plastic pollution. It has some very useful summary graphics to illustrate the quantities and types of microplastics, and their flows into our environment and on to people.
“We know that plastics are everywhere in the marine environment; we find them in Antarctica and in the deepest parts of the ocean. Of course, their abundance is highest in our estuaries and coastal ecosystems.
“There are many sources of plastics and many ways they are transported in the environment. This makes the problem difficult for people to deal against the backdrop of all the other stresses imposed on the marine environment.
“This means that it is really important we understand what the consequences of microplastic pollution are to the way that our marine environment works and contributes benefits to people.
“The area of ecosystem effects is where we have been working at the University of Auckland and it’s an area which is very loosely addressed in this paper, yet our research shows that ecosystem effects are apparent at low concentrations, with important consequences on the ecosystem services generated from estuaries and coasts.
“Importantly, the paper does consider the policy and management implications. Despite reviews produced both from the Royal Society and the Chief Science Advisors office, in New Zealand we have really been slow to grapple with the problem. We have no national monitoring of environmental loads or strategy for addressing the problem.
“Nevertheless, we are seeing positive actions on the part of individuals and business towards enhancing recycling opportunities and reducing the input of plastics into the environment in the first place. As we sign up to international agreements it will be increasingly important that we understand the nature of the problem in comparison to all of the other factors that impact our natural environment and understand the potential risks this poses to our environment and economy.”
Conflict of interest statement: Professor Simon Thrush has been working on microplastic pollution with colleagues for about the last 10 years. This research has been funded through philanthropic donations.