12 October 2016: China is today the largest emitter of certain toxic fluorinated chemicals in the world, as presented in a new study published in Environmental Science and Technology.
– Our field measurements have confirmed the theoretical calculations of emissions, says project leader Thanh Wang, researcher at Örebro University.
Co-project manager Dorte Herzke from NILU in Norway goes on to explain that the emissions of these substances to rivers in China are now as great as they were in Europe 10 years ago, before the EU ban of production came into force. Research has shown that these chemicals are harmful to animals and humans.
Teflon frying pans
Researchers from Norway, Sweden and China have measured the levels of 12 fluorinated substances at the mouths of 19 Chinese rivers. They studied two fluorinated substances in particular, PFOS (perfluorooctane sulfonate) and PFOA (perfluorooctanoic acid). PFOS is used, for example, in the manufacturing of firefighting foam, insecticides and chrome plating. PFOA is used in the manufacturing of PTFE, a coating material used to treat outdoorwear and for non-stick kitchen utensils (commercially known as Teflon).
– We have previously shown that the manufacture of PTFE is the main source of PFOA in the environment, says Ian Cousins, Professor at Stockholm University and co-author of the study.
The alternative possibly more hazardous than PFOS
There are explanations for the high levels in the Chinese estuaries:
– Chemical manufacturers in the US and Europe have phased out local production, and instead moved its manufacturing to China, since regulations are less strict there, says Thanh Wang, pointing out at the same time that emissions from the West have been “extremely high” in the past.
The researchers have also measured F-53B levels in Chinese rivers, a substance used as an alternative to PFOS, mainly in chrome plating.
– More studies are underway, also in Norway. There are signs that F-53B may be even more hazardous than PFOS, but so far its use has been relatively limited, says Thanh Wang and Dorte Herzke.
China world’s largest emitter
The use of PFOS is regulated by the Stockholm Convention which aims to limit the spread of persistent organic pollutants. PFOS was banned in the EU in 2008, and major manufactures in the US have agreed to stop using PFOA.
– We have provided strong evidence that China is the largest emitter of all these substances in the world today, and that they are discharged into the oceans of the world. Our study forms the basis for further research and can provide help in aligning international regulations, says Thanh Wang.
– We need to reduce the consumption of fluorinated substances worldwide, continues Dorte Herzke.
– That is the only way we can we make it less lucrative to move production to China and other countries where regulation is weaker.
Ian Cousins stresses that toxic fluorinated chemicals is not only China’s problem, but a global, long-term pollution problem. He also points out that PFOA is likely to be included in the Stockholm Convention soon.
The research project is a collaboration between Örebro University, Stockholm University, the Norwegian Institute for Air Research, and the Chinese Research Centre for Eco-Environmental Sciences. It was co-funded by the Norwegian Research Council and the Chinese Academy of Sciences.