Quantifying the Effect of Nano-TiO₂ on the Toxicity of Lead on C. dubia using a Two-Compartment Modeling Approach


Nanoparticles (NPs) can significantly influence toxicity imposed by toxic metals. However, this impact has not been quantified. In this research, we investigated the effect of nano-TiO2 on lead (Pb) accumulation and the resultant toxicity using water flea Ceriodaphnia dubia (C. dubia) as the testing organism. We used a two-compartment modeling approach, which included a two-compartment accumulation model and a toxicodynamic model, on the basis of Pb body tissue accumulation, to quantify the impact of nano-TiO2 on Pb toxicity. The effect of algae on the combined toxicity of Pb and nano-TiO2 was also quantified. The two-compartment accumulation model could well quantify Pb accumulation kinetics in two-compartments of C. dubia, the gut and the rest of the body tissue in the presence of nano-TiO2. Modeling results suggested that the gut quickly accumulates Pb through active uptake from the mouth, but the rest of the body tissue slowly accumulates Pb from the gut. The predicted Pb distribution within C. dubia was verified by depuration modeling results from an independent depuration test. The survivorship of C. dubia as a function of Pb accumulated in the body tissue and exposure time can be well described using a toxicodynamic model. The effects of algae on Pb accumulation in different compartments of C. dubia and the toxicity in the presence of nano-TiO2 were also well described using the two-compartment modeling approach. Therefore, the novel two-compartment modeling approach provides a useful tool for assessing the effect of NPs on aquatic ecosystems where toxic metals are present.


Civil, Architectural and Environmental Engineering

Second Department

Biological Sciences

Research Center/Lab(s)

Center for Research in Energy and Environment (CREE)


The authors greatly appreciate the support from the Center for Research in Energy and Environment (CREE) at Missouri S&T.

Keywords and Phrases

Algae; Lead; Nano-TiO 2; Toxicity; Toxicodynamic model; Two-compartment model

International Standard Serial Number (ISSN)

0045-6535; 1879-1298

Document Type

Article - Journal

Document Version


File Type





© 2020 Elsevier Ltd, All rights reserved.

Publication Date

01 Jan 2021

PubMed ID