[Advances in the Study of Endogenous Pollutants and Potential Risks in Biochar]

As an emerging adsorbent， biochar has shown a broad application prospect in the field of environmental remediation. However， in recent years， many studies have confirmed that their own pollutants have potential environmental risks in practical application. This paper summarizes the source of biochar endogenous inorganic pollutants （heavy metals， metalloid， etc.） and organic pollutants （PAHs， EPFRs， etc.）， occurrence characteristics， and potential environmental application risk and further explores the environmental release mechanism of biochar endogenous pollutants （physical release， chemical release， and biological-mediated release）. The study shows that the endogenous pollutants of biochar showed the dynamic migration characteristics in different environmental media （soil， water， and atmosphere）， and their migration behavior was influenced by many factors. Meanwhile， the ecotoxicological effects of endogenous pollutants of biochar were also summarized. Finally， this paper prospects the future research direction， pointing out that the key to reduce the risk of endogenous pollutant release of biochar is to consider the control of reaction process parameters and planning the application site of biochar.