Preface

Agricultural activities are fundamental for producing food around the world, but they are also major contributors to environmental pollution. They contaminate soil, water, and air matrices through the release of organic and inorganic pollutants. Pesticides (e.g., herbicides, fungicides, and insecticides), heavy metals, and antibiotics are among the most used pollutants in agriculture. Pesticides are potentially harmful substances due to their persistence, toxicity, and bioaccumulation in the environment. Many of these molecules can contaminate groundwater, mainly due to the lack of efficient treatment methods to reduce their concentration in water resources. However, it is important to point out that extensive industrial activity also contaminates the environment.

In contact with the environment, organic and inorganic pollutants are subject to physical and chemical processes that regulate their behavior and fate. Some molecules accumulate on the surface and subsurface of the soil, with direct consequences on microorganisms and mainly autotrophic organisms, including many plant species. Other molecules can reach waterways. Moreover, one must also consider the airborne displacement of herbicide molecules enhanced by physicochemical characteristics, unfavorable weather conditions, and inadequate application technology. Toxicity and persistence make pesticides a serious environmental concern, making it necessary to introduce additional technologies to adequately remove these compounds from the environment.

In view of this, and of the potential impact that these molecules can have when present in the environment, new techniques to remediate the presence of chemical molecules in the environmental matrix have been presented as efficient alternatives for the reduction of contamination and pollution caused by these molecules and their metabolites, as biotic and abiotic processes. The bioremediation of soils contaminated by organic and inorganic pollutants consists of reducing the levels of contaminants to levels that are safe and compatible with the protection of human health, either by preventing or hindering the spread of harmful substances to the environment.

This book presents a clear overview of the applications of different technologies for bioremediation of organic and inorganic pollutants that will help improve human life and ecosystems.

> **Kassio Ferreira Mendes and Kamila Cabral Mielke** Department of Agronomy, Federal University of Viçosa, Viçosa, Brazil

> > **Rodrigo Nogueira de Sousa** Department of Soil Science, University of São Paulo, Piracicaba, Brazil
