A review on global spatial distribution, sources and toxicity of perfluoroalkyl acid and prospect in the cryosphere.

Perfluoroalkyl acid analogs (PFAAs) are a class of chemically stable environmentally persistent organic pollutants (POPs) that are difficult to degrade and have a strong capacity to accumulate in the human body. PFAAs have been found to be biotoxic to humans and have been detected in various environmental media, especially in the cryosphere at trace concentrations. The cryosphere, sensitively responds to climate change, plays a crucial role in the global water, carbon and energy cycles. However, researches on cryosphere PFAAs especially in Tibetan Plateau (TP) is limited. Therefore, we summarize the physicochemical properties, physiological toxicity, spatiotemporal distribution, sources, diffusion and migration pathways, as well as analysis and removal methods of PFAAs in the cryosphere regions. The results show that PFAAs pollutants are mainly produced and distributed in the more economically developed countries in Europe and the United States, as well as in East Asia, and PFAAs can be transported by atmospheric circulation and water cycle to remote regions including cryosphere regions. The current detection methods for PFAAs in cryosphere need to be further refined for increased accuracy and convenience. There is also a need to develop more effective removal methods that will reduce the environmental and human threats posed by these PFAAs. Finally, we propose key scientific questions for future research in cryosphere including PFAAs redistribution influenced by cryosphere changes, human activities, and the interaction of other spheres. [ABSTRACT FROM AUTHOR]