High levels of ingested microplastics in the human body have the potential to have harmful effects, a new study reveals.
The research - the first of its kind to quantify the levels of microplastics which may lead to harmful effects in human cells - has been led by researchers at the Hull York Medical School and the University of Hull.
Evangelos Danopoulos, lead author and PHD student at Hull York Medical School, said: “This is the first-time scientists have attempted to quantify the effects of the levels of microplastics on human cells using a statistical analysis of the available published studies. What we have found is that in toxicology tests, we are seeing reactions including cell death and allergic reactions as potential effects of ingesting or inhaling high levels of microplastics.”
The study compared the concentrations of microplastics that affected cell viability to the concentrations that we are exposed to by ingesting contaminated food and water using three previous studies by Mr Danopoulos and the Human Health and Emerging Environmental Contaminants research group at the University of Hull.
These studies focused on microplastic contamination of drinking water, seafood and table salt and revealed high levels of human exposure to microplastics from consuming these.
The team then compared these levels to the doses that have caused adverse effects on human cells within the toxicology studies.
The toxicology studies reviewed tested for 5 categories of effects:
- cytotoxicity (cell death/viability),
- immune responses (including allergic reactions),
- whether microplastics can affect the cells membranes in any way or cross inside them,
- the cause of oxidative stress (leads to cell and tissue damage) and
- genotoxicity (damage genetic information in cells).
The first four were found to be affected by exposure to microplastics at certain levels.
Mr Danopoulos, said: “Our research shows that we are ingesting microplastics at the levels consistent with harmful effects on cells, which are in many cases the initiating event for health effects. However, the biggest uncertainty at the present time is how ingested microplastics are excreted from the body. This is a crucial point to understand the true level of risk.
Furthermore, our analysis of the data showed that cell viability depends on the shape of the microplastics. Irregularly shaped microplastics, which are the majority found in the environment, are more hazardous than spherical.
“So far, most toxicology studies have been testing spherical microplastics. There needs to be a shift to testing irregularly shaped ones.”
Mr Danopoulos says that although tests have shown effects on cells in toxicology tests, no research is yet available showing what happens to microplastics after they enter the human body.
He said: “The Human Health and Emerging Environmental Contaminants research group was established at the University to focus on the effects of contaminants on the human body. Our research continues into the effects of microplastics and other contaminants.”
The paper is published in the Journal of Hazardous Materials.
Notes to Editors:
The publication of the study continues to build on the University of Hull’s reputation for plastics and other environmental research:
- On world ocean day in 2018, a study of microplastics in mussels reported that 100 per cent of mussels sampled from around the UK coast contained microplastics or other debris. Scientists from the University of Hull and Brunel University, London collected samples from eight locations around the UK’s coastline as well as from eight unnamed supermarkets, representing eight different, unnamed brands. The study was published in the journal Environmental Pollution and attracted widespread coverage in the media.
The same author team Professor Jeanette Rotchell, Dr Maureen Twiddy, Evangelos Danopoulos and Lauren Jenner recently published a systematic review and meta-analysis of studies of microplastics in drinking water and table salt as well as a study into the variable levels of microplastics in different seafood tissue parts. (This author team is part of the Human Health and Emerging Environmental Contaminants research group which also includes Dr Laura Sadofsky, Dr Andrew Boa, Dr Roger Sturmey, Dr Ireneous Soyiri, Dr Justin Sturge).
- The Human Health and Emerging Environmental Contaminants research group, which brings together researchers from the University of Hull and Hull York Medical School, focuses on understanding the effect of contaminants on the human respiratory and reproductive systems, in addition to the gastrointestinal tract (as above). Respiratory work carried out by Lauren Jenner and led by Dr Laura Sadofsky has so far focussed on microplastics, having determined the level and characteristics of microplastics within the indoor, home environment. With this knowledge they hope to discover whether microplastics can be found within the human lungs and whether these particles have an adverse effect on respiratory health. Studies on reproductive systems, carried out by Vasiliki Papachristofi and led by Dr Roger Sturmey, are investigating the way in which newly emerging and established environmental contaminants affect the tissues of the female reproductive system in ways that change the periconceptual (around the time of conception) environment and the early stages of embryo development.
- Previous research led by Dr Cath Waller at the University of Hull, along with colleagues at the British Antarctic Survey, showed how the levels of microplastic particles accumulating in the Southern Ocean, around Antarctica, are much worse than expected. Dr Waller leads the University’s Plastics in the Environment Research Group focussing on the environmental and social impact of plastics.
- PhD Researcher, Freija Mendrik, recently published her research on the impacts of plastics on corals. The work exposed corals to different types of microplastic and measured photosynthetic yields, gross photosynthesis and net respiration. The work also tested whether impacts increased at higher temperatures that replicate ocean warming under climate change. Negative impacts were observed. However these effects were species-specific and the type of microplastics was found to be important with fibres (from clothes) causing the biggest (40%) drop in photosynthetic yield for the corals, which could reduce growth and survival.
Other environmental research
- The University of Hull is recognised as a leading centre for research into environmental issues of global importance and interest. Researchers specialise in areas such as climate change, globalisation, renewable energy and low-carbon futures. Reducing the demand for single-use plastics and protecting our waters by reducing the impact of chemicals, plastics and synthetics are also key.
- One of the University’s distinctive features is its strong research culture of collaboration and interdisciplinary working. Researchers across the University collaborate with University institutes such as the Energy and Environment Institute which has established a Plastics Collaboratory to bring together researchers across campus working on the critical issue of plastics in the environment and how to address this through evolving a new circular plastics economy.
- The Energy and Environment Institute at the University of Hull brings together the skills and capabilities of leading researchers to tackle global challenges related to climate change and a low carbon transition, and their consequences for society and livelihoods. Home to over 100 staff and PhD researchers, the Institute is leading research in some of the areas of the world most at-risk from climate change, including flood prone areas such as Vietnam’s Mekong and Red River deltas, the Congo River in Africa, as well as locations much closer to home.
Other University partnerships focused on tackling some of the world’s greatest environmental challenges include:
- Aura Innovation Centre, a University-led initiative, that works with SMEs and provides space for businesses to accelerate low-carbon projects, drive green innovation and deliver clean business growth. The Aura Centre for Doctoral Training, led by the Energy and Environment Institute, will appoint more than 70 PhD scholarships in offshore wind energy and the environment over the next 4 years.
- THYME: The University of Hull’s Energy and Environment Institute is collaborating with partners at the University of York and Teesside University on a £5 million project to develop the bioeconomy across Yorkshire, the Humber region and the Tees Valley, building on the existing knowledge and innovation in the region. The University of Hull brings particular expertise in the bioeconomy, particularly on aspects of biofuels, renewable energy and the environment, as well as logistical aspects of the wider circular economy.
In November 2020, the University of Hull announced an ambitious eight-year plan to become carbon neutral by 2027, pledging a commitment towards a strong, sustainable future.
The University is introducing a range of measures, including a transition to renewable sources of energy to power the campus and reducing energy usage through optimising our estate and campus infrastructure.