Abstract for OpenTox Summer School 2023

Ecotoxicological risk assessment of diverse groups of organic contaminants employing QSTR and Species Sensitivity Distribution technique

The impact of environmental contaminants extends to a wide range of species, and the consequences are influenced by the unique biology of each species and the circumstances of exposure. While it is possible to evaluate the effects of a specific environmental contaminant on a particular species, it becomes challenging to assess the numerous environmental contaminants across all affected species without sufficient information about the biology and exposure conditions of each species. To overcome this challenge, we can employ empirically derived chronic and acute exposure thresholds to establish a Species Sensitivity Distribution (SSD) for each species. These SSD models enable us to predict the toxicity of a new compound based on the response of species with varying sensitivities. For our study, we gathered and curated 3,250 entries from the ECOTOX database, which are associated with environmental toxicity assays conducted on 14 species groups. We constructed SSD models for acute toxicity using EC 50 (935 entries) and LD 50 (1,077 entries) data, as well as chronic toxicity using NOEC (667 entries) and LOEC (571 entries) data. Moreover, linear quantitative-structure toxicity relationship models were developed in order to predict missing toxicity values across different groups of species. Consequently, the SSD models developed in this study were proven to effectively address the scope of exposures in modern toxicology.

Kabiruddin Khan 1,2, Nyssa Tucker 3, Holli-Joi Martin 3, Vinicius M. Alves 4, Barry
Hardy 1,2 *, Eugene Muratov 3 *

1 OpenTox Association, Basel, Switzerland
2 Edelweiss Connect GmbH, Basel, Switzerland
3 Laboratory for Molecular Modeling, UNC Eshelman School of Pharmacy, University of
North Carolina, Chapel Hill, North Carolina 27599, United States
*Corresponding author