Global worries regarding the continuous toxic emissions increase due to the growing problems found in the environment. Some systems have emerged as alternatives to evaluate and avoid risks of exposure of human population to these substances. These systems that are used to evaluate the exposure to these specific substances have been developed and are explored in this book. Ecotoxicological techniques that can lead to risk assessment are also evaluated and shall be available to prevent pollution problems. In addition, early-life-stage tests and biomarkers are important tools for toxicity determination and pollution prevention. This book aims to contribute to biofuels risk assessment modeling by determining the toxic effects caused by the water soluble fractions (WSFs) of three different biofuels. The effect of the addition of different concentrations of crude oil on the physicochemical characteristics of soils was investigated. The adverse health effects of heavy industrial and agricultural pollution, particularly in eastern Slovakia, is explored.