Introduction to Microconstituents

Abstract

The presence of microconstituents (MCs) (also known as contaminants of emerging concern (CECs)) in the environment has been recognized as a worldwide concern. In particular, water pollution by CECs is becoming a major global problem, which requires ongoing evaluation of water resources policies at all levels and the use of effective and innovative wastewater treatment processes for their removal. This chapter provides an introduction to CECs, their classification, sources, properties, and their impact on the environmental ecosystem and human health. The presence of CECs in the environment is the result of uncontrolled urbanization, development of industry, healthcare activities essential to support human well-being, agriculture, and transportation activities. CECs include a wide range of substances, produced by humans, considered indispensable for modern society. The wide range of compounds that comprise CECs continues to expand as new chemicals are being identified as part of this category due to advances in analytical procedures. A broad variety of compounds can be included in the CECs, including pharmaceuticals and personal care products, pesticides/herbicides, food additives, artificial sweeteners, disinfection by-products, flame/fire retardants, surfactants, and algal toxins. The release of CECs into the environment depends on different sources and pathways, which are described in this chapter. The physico-chemical properties of CECs, such as solubility, polarity, structural complexity, functional groups, sorption coefficients, and lipophilic characteristics that impact their environmental degradation are presented. The MCs present in water, wastewater, soil, and air can harm humans as well as other living entities in the ecosystem by bioaccumulation, toxicity, or by altering natural metabolic activities. The ill effects on human health and alterations in animal behavior and plant growth due to exposure to CECs have been discussed. The structure of the book along with a brief description of all chapters are included in this chapter.