A world-first Australian clinical trial has found regular blood or plasma donations can reduce levels of toxic PFAS chemicals in the blood by up to 30 percent. The trial is the first to find an effective intervention that reduces levels of the substances known as “forever chemicals”.
Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are a group of manufacturing chemicals encompassing over 4,000 different specific compounds. PFAS can be found in a variety of household objects, from carpets to non-stick cookware, but perhaps the most controversial use of PFAS has been in firefighting foams.
Firefighters have historically been exposed to extraordinarily high levels of PFAS. A growing body of research has associated high blood levels of PFAS to a variety of adverse health effects, including obesity, liver and thyroid abnormalities and impaired immune functions.
Increasing recognition of PFAS toxicity has led to plenty of work removing the chemicals from common products and decontaminating exposed environments. But until now clinicians had no way to help those already exposed to what are known as “forever chemicals” due to how long they can persist in a human body.
This new trial enrolled 285 Australian firefighters with elevated blood levels of a PFAS called perfluorooctane sulfonate. The cohort was split into three groups: those donating plasma every six weeks for a year, those donating blood every 12 weeks for a year, or a control group with no intervention.
“The results from the study show both regular blood or plasma donations resulted in a significant reduction in blood PFAS levels, compared to the control group,” reported lead author Robin Gasiorowski. “While both interventions are effective at reducing PFAS levels, plasma donations were more effective and corresponded to a 30 per cent decrease.”
While the study does offer evidence for an intervention that can directly reduce blood PFAS levels the researchers did not investigate whether this drop results in clinical health benefits. Because the long-term effects of PFAS exposure is still a source of investigation and debate, the researchers call for more study to understand these effects.
Speaking to ABC News in Australia, study co-author Mark Taylor said the findings offer exposed firefighters a degree of relief as many were not keen on waiting decades to see what deleterious health effects could come up in the future.
"They don't focus on the clinical outcomes, they take a precautionary approach," said Taylor. "They say 'we don't want these chemicals in our body, we don't want to be guinea pigs to see what's going to happen to us in 10, 20, 30 years. Let's get them out'."
And what to do with the donated blood? The researchers do stress that elevated serum PFAS levels do not currently exclude someone from donating blood and there currently is no specific threshold of PFAS contamination that would stop donated blood being distributed.
“Perfluoroalkyl and polyfluoroalkyl substances are ubiquitous, and no threshold has been identified that poses an increased risk to recipients of donated blood components,” the researchers write in the new study. “Our study does not inform this risk, but blood authorities should continue to monitor the evidence on the possible health effects of PFASs and consider the possible implications of elevated PFAS levels in blood donors.”
Mick Tisbury, an officer in Fire Rescue Victoria, was part of developing the initial study. He said these findings offer the first active solution to a problem facing many firefighters around the world.
“Firefighters often put the health and safety of others before their own health, so it is pleasing that the results from this research can be used to improve the health of firefighters who have acquired high PFAS levels through vital community work,” Tisbury said. “The findings will not only benefit the firefighting community but others working in high-risk sectors who are exposed to PFAS chemicals.”
The new study was published in JAMA Network Open.
Source: Macquarie University
