Initial studies test graphene as an emerging biological contaminant – where microplastics and pharmaceuticals have fallen.

Graphene, a truly revolutionizing nanomaterial with potential that is hard to overstate, may continue to be developed without acute risk to human health, research suggests.

Science has discovered an emergence of contaminants as unanticipated drawbacks to technological development – notably microplastics and pharmaceuticals that have made their way into our water supply. These emerging contaminants are a group of pollutants that can have a lethal impact on human and wildlife endocrine systems, even in trace quantities.

A study published in the journal Nature Nanotechnology has shown that controlled exposure to pure graphene oxide through inhalation has no short-term adverse effects on lung or cardiovascular function.

"This is the first-ever controlled study involving healthy people to demonstrate that very pure forms of graphene oxide-of a specific size distribution and surface character-can be further developed in a way that would minimize the risk to human health," said Professor Kostas Kostarelos of the University of Manchester and the Catalan Institute of Nanoscience and Nanotechnology in Barcelona. "It has taken us more than 10 years to develop the knowledge to carry out this research, from a materials and biological science point of view, but also from the clinical capacity to carry out such controlled studies safely by assembling some of the world's leading experts in this field."

No adverse effects observed

Researchers from the Universities of Edinburgh and Manchester recruited volunteers to take part in the clinical study. The 14 volunteers breathed the material through a face mask for two hours while in a mobile exposure chamber from the National Public Health Institute in the Netherlands.

This water-compatible form of the world's thinnest, super strong, and super flexible material – thousands of times thinner than a human hair – will need further research to determine whether higher doses or longer exposure of this and other forms would carry additional health risks.

There has been active global interest in developing this incredibly versatile material – first isolated by scientists in 2004 with applications across the fields of electronics, screens and solar panels, clothing, medicine, air and water purification.

In medicine alone, graphene technologies can be used in targeted therapeutics against cancer and other health conditions in the form of implantable devices and sensors, but not before being rigorously tested for any potential adverse effects.

"Nanomaterials such as graphene hold such great promise, but we must ensure they are manufactured in a way that is safe before they can be used more widely in our lives," said Dr. Mark Miller of the University of Edinburgh's Centre for Cardiovascular Science. "Being able to explore the safety of this unique material in human volunteers is a huge step forward in our understanding of how graphene could affect the body. With careful design we can safely make the most of nanotechnology."

No adverse effects on lung function, blood pressure or inflammation in the blood were observed – these and other biological parameters were measured before the exposure and at two-hour intervals.

Weeks later, the volunteers returned for repeated controlled exposures to either a different size of graphene oxide or clean air for further comparison. A slight suggestion that inhalation of the material could influence how blood clots was observed, but the team noted that this effect was very small.

"The discovery that this type of graphene can be developed safely, with minimal short term side effects, could open the door to the development of new devices, treatment innovations and monitoring techniques," said Professor Bryan Williams, chief scientific and medical officer at the British Heart Foundation. "We look forward to seeing larger studies over a longer timeframe to better understand how we can safely use nanomaterials like graphene to make leaps in delivering lifesaving drugs to patients."