Department of Ecological Science, Faculty of Earth and Life Sciences, VU University, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands.
J Hazard Mater. 2013 Oct 15;261:405-13. doi: 10.1016/j.jhazmat.2013.07.032. Epub 2013 Jul 24.
The aim of the present study was to investigate the influence of Ca and pH on the uptake and effects of Cu in Folsomia candida (Collembola). Assuming that soil pore water is the main route of exposure, F. candida were exposed for seven days to Cu in simplified soil solutions at different Ca concentrations and different pH levels. A hormetic-type effect was seen for the effect of Cu on F. candida survival. Toxicity of Cu was slightly decreased and Cu uptake increased at the highest Ca concentrations. Cu toxicity and uptake were not significantly affected by pH. Conditional binding constants for Cu(2+), Ca(2+) and H(+), calculated with a Langmuir isotherm, were used to relate Cu toxicity to the fraction of occupied binding sites (BL). The estimated 50% effect level (fCu-BL50) was 0.14 when all data were combined. To verify the Langmuir parameters, binding constants calculated based on internal Cu concentrations were used to estimate predicted effects and compared with the measured values. A good correlation between predicted and measured survival indicated that the principles of a biotic ligand model may be applicable to explain Cu toxicity to F. candida in simplified soil solutions.
本研究旨在探讨 Ca 和 pH 对 Folsomia candida（弹尾目）对 Cu 的吸收和作用的影响。假设土壤孔隙水是主要的暴露途径，F. candida 在不同 Ca 浓度和不同 pH 值的简化土壤溶液中暴露 7 天。Cu 对 F. candida 生存的影响呈现出一种兴奋型效应。在最高 Ca 浓度下，Cu 的毒性略有降低，Cu 的吸收增加。Cu 的毒性和吸收不受 pH 值的显著影响。用 Langmuir 等温线计算的 Cu(2+)、Ca(2+)和 H(+)的条件结合常数，用于将 Cu 毒性与占据结合位（BL）的分数相关联。当所有数据合并时，估计的 50%效应水平（fCu-BL50）为 0.14。为了验证 Langmuir 参数，基于内部 Cu 浓度计算的结合常数用于估计预测的效应，并与测量值进行比较。预测的和测量的生存之间的良好相关性表明，生物配体模型的原理可能适用于解释简化土壤溶液中 Cu 对 F. candida 的毒性。
