Lung exposure: combustion of graphene-containing plastics studied
Empa researchers have studied residues from the incineration of graphene-containing plastics. Conclusion of the study: Incinerated composite materials containing graphene nanoparticles can be classified as harmless in the case of acute exposure.
Due to its exceptional properties, graphene is now added to a wide range of plastics. For example, the carbon-based material improves the conductivity and stability of composites. Empa researchers are currently investigating the health risks of these comparatively new composite materials in several studies. The most recent investigations are looking at the residues of graphene nanoplatelets that can be produced after the composites are incinerated in waste incinerators or in a fire accident.
A realistic lung model in the petri dish
Since the human organism is most likely to come into contact with graphene particles via the respiratory tract, the researchers used the 3D lung model developed at Empa with cell cultures for the toxicity tests. The team led by Peter Wick of Empa's Particles-Biology Interactions laboratory in St. Gallen exposed lung cells to residues from the combustion of composite materials containing graphene nanoplatelets. To estimate as realistically as possible the amount of graphene particles to which people are typically exposed, a team led by Jing Wang of Empa's Advanced Analytical Technologies Laboratory examined and quantified the combustion residues of the graphene composites. Researchers from Empa's Advanced Fibers Laboratory were also involved in the interdisciplinary project.
No acute injury
Using this data, the team exposed the 3D lung model to realistic conditions so that predictions could be made about the acute toxicity of graphene nanoplatelets after combustion. The results showed that although combustion residues of plastic resins without graphene triggered already known reactions indicating a health risk. However, after contact with the graphene nanoplatelet residues, there was no further evidence of acute damage to lung cells, such as inflammatory reactions, oxidative stress or cell death.
In an earlier study, Empa researchers had already been able to show that the health risks of graphene dust produced by abrasion from polymer composites are negligible. The effects of prolonged exposure to graphene nanoparticles will now be investigated in more long-term studies.
Source: Empa
