Toxicological Assessment of Combined Chemicals in the Environment

Practitioners do not have an adequate understanding of how small changes in mixtures of chemicals will affect toxicity in an organism. The current belief is the mechanism of action must be known and similar for all chemical involved to be able to adequately predict mixture effects. This book provides a discussion of approaches, molecular mechanisms, and the challenges involved in the assessment of mixtures. In the first section of the book a brief introduction to the background and significance of combined toxicity is provided describing the degradation, oxidation, absorption, distribution, biotransformation and excretion of various compounds in the environment and organism. Section two introduces the main sources and enrichment mechanisms of different chemical mixtures and clarifies the biological exposure pathways of different compounds. In section three classical and emerging toxicological research models are introduced in detail, including various cell models and in vivo research models of model organisms with the case study; included are the combined molecular toxicity mechanism of heavy metals, pesticides, persistent organic pollutants (POPs), pharmaceutical and personal care products (PPCP), phthalates (PAEs), microplastics and flame retardants respectively. Through the description of compound emission, migration, accumulation and transformation process in the previous sections and the analysis of the combined molecular toxicity, section four introduces computer mathematical modeling methods of hazard assessment of compound mixture. Sections five and six detail challenges and future trends and provides a conclusion on the topic.