Biotic ligand modeling (BLM) approaches are already applied to predict the bioavailability and possible risk of metals in surface water, but need further development for soils. The present study investigated the effect of major cations (Ca2+, Mg2+, Na+, K+, and H+) on cadmium bioaccumulation in the springtail Folsomia candida. To avoid the complexity of real soils and enable control of elemental speciation in the exposure medium, the animals were exposed to different cadmium concentrations in an inert quartz sand‐solution medium. Accumulation of cadmium in the animals was measured after 7 days exposure at different cation concentrations. Among the cations, only Ca2+ significantly affected the uptake of cadmium in the springtails. Mg2+ also had higher effects compared with other selected cations. Using a BLM approach, the uptake of cadmium in the animals predicted by taking into account both Ca2+ and Mg2+ activities correlated well with the measured values (R2 = 0.68). The final estimated conditional binding constants for cadmium (log KCd‐BL), Ca (log KCa‐BL), and Mg (log KMg‐BL) of 1.06, 2.14, and 1.23 L/mol, respectively, were in agreement with previously reported values. The match between predicted and measured uptake data confirms the applicability and usefulness of the BLM for predicting the bioavailability of cadmium to springtails and opens the way for its application in soil. Environ Toxicol Chem 2024;00:1–7. © 2024 SETAC

中文翻译：

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主要阳离子对暴露于沙溶液介质中的念珠菌中镉吸收影响的生物配体模型

生物配体建模（BLM）方法已应用于预测地表水中金属的生物利用度和可能的风险，但需要进一步开发土壤。本研究调查了主要阳离子（Ca2+, 镁2+, 钠+, K+，和H+）关于跳虫中镉的生物累积念珠菌。为了避免真实土壤的复杂性并能够控制暴露介质中的元素形态，将动物暴露在惰性石英砂溶液介质中不同浓度的镉中。接触不同阳离子浓度 7 天后，测量动物体内镉的累积情况。阳离子中，只有 Ca2+显着影响跳虫对镉的吸收。镁2+与其他选定的阳离子相比，也具有更高的效果。使用 BLM 方法，通过考虑 Ca 和 Ca 来预测动物对镉的吸收。2+和镁2+活动与测量值密切相关（右2= 0.68）。最终估计的镉条件结合常数（logK镉-BL), 钙 (日志K钙-BL）和镁（对数K镁-BL）分别为 1.06、2.14 和 1.23 L/mol，与之前报道的值一致。预测和测量的吸收数据之间的匹配证实了 BLM 在预测跳虫中镉的生物利用度方面的适用性和有用性，并为其在土壤中的应用开辟了道路。环境毒理化学2024；00：1–7。© 2024 SETAC 版权所有