Graphene Toxicity

Researchers from the Karolinska Institute in Sweden and the Catalan Institute of Nanoscience and Nanotechnology (ICN2) in Spain have found that oral exposure to graphene oxide (GO) modulates the composition of the gut microbiome in adult zebrafish and can influence the crosstalk between the microbiome and immune system.

"This shows that we must factor the gut microbiome into our understanding of how nanomaterials affect the immune system," said the paper's corresponding author Bengt Fadeel, professor at the Institute of Environmental Medicine, Karolinska Institutet. "Our results are important for identifying the potential adverse effects of nanomaterial and mitigating or preventing such effects in new materials."

The European Union Observatory for Nanomaterials (EUON) has published a study that has systematically reviewed and critically assessed the potential health and environmental effects of graphene, graphene oxide, and other two-dimensional (2D) materials, based on existing public information of the last ten years.

It was explained that graphene’s rising popularity and broad application potential raise the need for more efforts in researching its safety aspects. The current study identified potential risks in specific scenarios, for example for surface water and soil located near point sources (such as production sites).

An international research team of the Graphene Flagship project, led by Empa, has conducted a study on the health risks of graphene-containing nanoparticles and found that graphene-based particles released from polymer composites after abrasion induce negligible health effects.

Graphene-related materials (GRMs) are often used to reinforce polymers. In small concentrations of up to five weight percent, GRMs can significantly enhance the strength, electrical conductivity and thermal transport of composites for a variety of applications. However, being a relatively new set of materials, graphene and GRMs need to be carefully assessed in order to identify potential adverse effects prior commercialization.

The potential toxicity of graphene and graphene oxide has been on people's minds lately. This is an area that has always received some attention, but recently there have been rumors and wild speculations about the adoption of graphene oxide and the risks involved.

Researchers have been studying the toxicity of graphene and graphene oxide for many years. While these materials have not yet been established as completely safe for use, there are quite a few research results that indicate that graphene can be relatively safe under the appropriate conditions.

Health Canada recently decided that the sale of certain graphene-enhanced face masks that were considered a hazard due to their graphene content can resume, after the agency assessed the masks and found "no health risks of concern."

Health Canada issued an advisory in April asking all distributors selling masks with graphene or biomass graphene to recall their products over potential inhalation risks after preliminary assessments made the agency fear a potential for inhaled graphene particles to cause lung effects, such as inflammation, in animals. These concerns made somewhat of an impact with consumers and producers alike, and various graphene-enhanced face masks responded to these claims.

Directa Plus recently stated that a research paper has been published in the journal iScience, supporting the use of its ‘functionalized’ graphene as an antimicrobial material in face masks.

The peer-reviewed paper said the company's G+ nanomaterials and those from graphene oxide provide a critical opportunity to significantly increase face mask efficacy.

Following recent concerns surrounding the use of graphene in face masks and Health Canada's warnings of "a potential that wearers could inhale graphene particles from some masks, which may pose health risks", several companies involved in the production of such masks released their comments on the matter.

Zen Graphene Solutions, which developed a graphene-based virucidal ink and reported that it has a 99% effectiveness against COVID-19, released a statement saying that it is aware of the recent claims, and "is aligned and supportive of the steps taken to regulate the use of graphene and remove products that are unsafe for the public". It went on to state that its own products have been found safe in various "comprehensive testing". Later on, Zen also submitted various data requested by Health Canada - including final results received from Nucro-Technics on skin irritation and sensitivity that confirmed ZENGuardâ„¢ did not lead to any irritation or sensitivity.

Despite the surge of graphene-enhanced face masks that's been evident lately, government authorities like Health Canada recently issued warnings on the use of such graphene masks, cautioning against "a potential that wearers could inhale graphene particles from some masks, which may pose health risks."

This potential threat is followed by the directive to not use these face masks, and Health Canada, for one, is advising Canadians not to use face masks that contain graphene at all. A recent PR stated: "Until the Department completes a thorough scientific assessment and has established the safety and effectiveness of graphene-containing face masks, it is taking the precautionary approach of removing them from the market while continuing to gather and assess information. Health Canada has directed all known distributors, importers and manufacturers to stop selling and to recall the affected products. Additionally, Health Canada has written to provinces and territories advising them to stop distribution and use of masks containing graphene. The Department will continue to take appropriate action to stop the import and sale of graphene face masks".

Researchers from Empa and the Adolphe Merkle Institute (AMI) in Fribourg have conducted studies on a 3D lung model to examine the behavior of graphene and graphene-like materials once they have been inhaled.

The lung model at Adolphe Merkle Institute (AMI)

Thanks to the 3-D lung model, the researchers have succeeded in simulating the actual conditions at the blood-air barrier and the impact of graphene on the lung tissue as realistically as possible without any tests on animals or humans. It is a cell model representing the lung alveoli. Conventional in vitro tests work with cell cultures from just one cell type the newly established lung model, on the other hand, bears three different cell types, which simulate the conditions inside the lung, namely alveolar epithelial cells and two kinds of immune cells macrophages and dendritic cells.

A team of Korean researchers recently conducted an inhalation toxicology study of graphene, as much questions have been raised on graphene's potential health and safety risks.

The study was done using a nose-only inhalation system for 28 days (6 h/day and 5 days/week) with male Sprague-Dawley rats that were then allowed to recover for 1-, 28-, and 90-day post-exposure period. Animals were separated into 4 groups (control, low, moderate, and high) with 15 male rats (5 rats per time point) in each group.