Department of Radiochemistry and Environmental Chemistry, Institute of Chemical Sciences, Faculty of Chemistry, Maria Curie-Sklodowska University in Lublin, Pl. M. Curie-Sklodowskiej 3, 20-031 Lublin, Poland.
Department of Chromatography, Institute of Chemical Sciences, Faculty of Chemistry, Maria Curie-Sklodowska University in Lublin, Pl. M. Curie-Sklodowskiej 3, 20-031 Lublin, Poland.
J Hazard Mater. 2022 Oct 15;440:129795. doi: 10.1016/j.jhazmat.2022.129795. Epub 2022 Aug 18.
Biochar applied into the soil is recommended as an effective tool for increasing its properties and crop productivity. However, biochar can contain some potentially toxic compounds such as polycyclic aromatic hydrocarbons (PAHs). Moreover, during biochar production or environmental application (e.g. as soil fertilizer), more toxic PAHs derivatives containing nitrogen, oxygen or sulfur can be formed. There is a lack of information on how the environmental factors affect the bioavailability of such compounds during the long-term application of BC into the soil. In the presented studies the effects of physical (freeze-thaw cycles) and chemical aging (temperatures 60 °C and 90 °C) on the total and bioavailable content of PAHs and their derivatives were estimated. The results indicate that long-term (6 months) aging affected the physicochemical characteristic of biochars promoting the formation of new C and O-containing species on the BC surface increasing their polarity and hydrophilicity. Physical and chemical aging promoted the formation of compounds with higher molecular weight and a significant (up to 550 %) increase in the bioavailability of PAHs and their derivatives. The results of this study highlight the importance of the bioavailable fraction of PAHs and their derivatives for evaluation of the toxicity of aged biochar.
生物炭施入土壤被推荐为一种增加土壤性质和作物生产力的有效工具。然而，生物炭可能含有一些潜在的有毒化合物，如多环芳烃（PAHs）。此外，在生物炭生产或环境应用（例如作为土壤肥料）过程中，可能会形成更多含有氮、氧或硫的毒性更高的 PAHs 衍生物。关于环境因素如何影响长期施入土壤的 BC 中此类化合物的生物利用度，信息仍然缺乏。在本研究中，评估了物理（冻融循环）和化学老化（温度为 60°C 和 90°C）对 PAHs 及其衍生物的总量和生物可利用量的影响。结果表明，长期（6 个月）老化影响了生物炭的理化特性，促进了 BC 表面上新的含碳和含氧物种的形成，增加了其极性和亲水性。物理和化学老化促进了高分子量化合物的形成，并使 PAHs 及其衍生物的生物利用度显著增加（高达 550%）。本研究的结果强调了评估老化生物炭毒性时 PAHs 及其衍生物的生物可利用部分的重要性。
