The latest amendment to the Montreal Protocol took place in Kigali, Rwanda in 2016 and introduced a phase-down schedule for HFCs (hydrofluorocarbons). HFCs, used as refrigerants and in other applications, are potent greenhouse gases with a Global Warming Potential (GWP) up to five thousand times greater than carbon dioxide.
RPA recently conducted a study for the Norwegian Environment Agency to investigate the environmental and health effects of HFO (hydrofluoroolefin) refrigerants. These are alternative refrigerants to the aforementioned HFCs and have zero ozone depletion potential and low GWP. However, the final atmospheric HFO degradation products, such as trifluoroacetic acid (TFA), may have environmental and human health effects; TFA is a highly persistent pollutant which accumulates in terminal water bodies.
The RPA study team reviewed scientific literature and consulted with academic experts, industry and NGOs. A number of knowledge gaps were identified during the study which will need to be addressed by future studies to conclude whether TFA will have negligible effect on the environment. Many of these gaps concerned the toxicity data for TFA being inadequate thus preventing a thorough assessment of the effects this substance may have on the wider environment. Furthermore, HFO emissions were projected up to 2100 based on the predicted growth in use of HFO refrigerants. A risk assessment was then performed to assess how the future use of HFOs and their subsequent emissions would affect the environment globally up to 2100. The risk assessment indicated the toxicity risk of TFA to organisms and human health appears to be low.
The final report can be accessed here.