A new report has highlighted the possible environmental and human health risks posed by some HFOs – the newest generation of synthetic refrigerants – breaking down in the atmosphere.
Report and statement of the downsides of HFO refrigerant usage has been produced by Refolution Industriekälte GmbH, a European refrigeration company that specialises in low-temperature systems using R729 (air). It brings together a wealth of studies already widely circulated, and points to new evidence of links between trifluoroacetic acid (TFA) and health concerns.
As part of the move to refrigerants that have a lower global warming potential (GWP) under the Kigali Amendment, new HFC and HFO refrigerants have been developed, and are now being introduced to HVAC&R systems.
When these escape to the atmosphere in the form of direct emissions, some break down and leave TFAs. One refrigerant that has a particularly high yield of TFA is HFO-1234yf, which is expected to replace R134a in mobile air conditioning technologies.
The report notes that TFAs are extremely persistent in the environment, have high mobility, and cannot be removed by current water treatment technology. “TFA is of high concern,” says the report, “since it accumulates in local lakes, freshwater and soils and potentially harms the aquatic environment.”
One study highlighted in the document is a long-time toxicity assessment from Germany, undertaken after concerning reports emerged of high TFA concentrations in waters in North Rhine-Westphalia. Rats were exposed for one year to TFA concentrations in freshwater, and displayed an increase of alanine aminotransferase (ALT) concentration, depending on the dosage of TFA. ALT is an indication of damage of the liver such as a liver-hypertrophy. In a study to developmental toxicity where TFA was given to pregnant rats, a temporary disfunction of the liver and kidney was observed.
The report also suggests that TFAs could impact thyroid function.
“There is a lack of information in the literature regarding the general effect of fluorochemical refrigerants on the thyroid,” says the report. “But it is known that halogen molecules influence the thyroid function. Therefore, HFO and TFA might also have the possibility to cause hypothyroidism and other consequences such as the brain development of children due to iodine deficiency during pregnancy.”
Based on these health concerns, the report recommends stopping the sale of HFOs.
“It is no question that sooner or later negative effects or an environmental disaster will happen,” the report warns. “It is only a question of when it will happen. Before bringing tonnes of chemicals into the environment, it needs to be proven that they are harmless to humans and the environment, especially regarding chemicals with high persistence such as TFA.”
To read the report, click here.