Scientists have discovered new health risks associated with microplastics

New research suggests that toxic chemicals added to plastics for flame resistance can enter the body through the skin when they come into contact with microplastics.

The study provides the first experimental evidence that chemicals found as additives in microplastics can leach into human sweat and then be absorbed through the skin into the bloodstream.

Many chemicals used as flame retardants and plasticizers have already been banned due to their adverse health effects, including liver or nervous system damage, cancer, and reproductive health risks. However, these chemicals are still found in the environment in old electronic devices, furniture, carpets, and building materials.

Although the harm caused by microplastics is not fully understood, there is growing concern about their role as drivers of human exposure to toxic chemicals.

Research results on chemisorption

The research team showed in a study published last year that chemicals leach from microplastics into human sweat. The current study now shows that these chemicals can also be absorbed through sweat across the skin barrier into the body.

In their experiments, the team used innovative 3D models of human skin as substitutes for laboratory animals and resected human tissue. The models were exposed for 24 hours to two common forms of microplastics that contain polybrominated diphenyl ethers (PBDEs), a chemical group commonly used in flame-retardant plastics.

Health outcomes and effects

The results were published in International environmentshowed that up to 8% of the exposed chemical could be absorbed through the skin, with wetter – or “sweatier” – skin absorbing higher levels of the chemical. The study provides the first experimental evidence of how this process contributes to levels of toxic chemicals in the body.

Dr Ofokroe Abafi, who now works at Brunel University, conducted the research while at the university University of Birmingham. He said: “Microplastic particles are everywhere in the environment, yet we still know relatively little about the health problems they can cause. Our research shows that they act as “carriers” for harmful chemicals, which can enter the bloodstream through the skin. These chemicals are persistent, so with continued or regular exposure there will be a gradual buildup to the point where they begin to cause damage.

Dr Mohamed Abdullah, Associate Professor in Environmental Science at the University of Birmingham and lead researcher on the project, said: “These findings provide important evidence for regulators and policy makers to improve legislation around microplastics and protect public health from harmful exposure. »

Professor Stuart Harrad, co-author of the study, added: “The study represents an important step forward in understanding the risks of exposure to microplastics to our health. Based on our findings, more research is needed to understand the different pathways of human exposure to microplastics and how to mitigate them.” of the risks resulting from this exposure.

In future research, the team plans to study other pathways through which microplastics may be responsible for toxic chemicals entering the body, including through inhalation and ingestion. This work is funded by a Marie Curie Research Grant, as part of the European Union's Horizon 2020 research and innovation programme.