Suggested Citation: Liu, Jiawen, Hui Li, John T. Harvey, Gordon Airey, Sijie Lin, Stephanie Ling Jie Lee, Yitan Zhou, Bing Yang (2023) Study on Leaching Characteristics and Biotoxicity of Porous Asphalt With Biochar Fillers. Transportation Research Part D 122
Permeable pavement leachate can be a potential issue as contained pollutants are washed off by rainfall. This paper investigated the leaching of porous asphalt mixture (PA) with different fillers via static tank leaching test. The effects of PA leachate on zebrafish were explored. The results show that within 1–2 days, the leaching of alkali, total nitrogen (TN), and total phosphorus (TP) fluctuates greatly, with acidic rain accelerating TN leaching. After long-term soaking, the pH of most leachate stabilizes at 8, and the leaching amounts of TN and TP in acidic leachant are 0.2 mg/kg and 0.04 mg/kg, respectively. PA with biochar leaches higher TN in deionized water (DI). Short-term leachate has little effect on zebrafish, while attention is needed when the damage degree or the Nemerow pollution index exceeds 5. Static tank leaching test is suitable for monolithic PA specimens, and leaching can be determined after 7d soaking in DI.