Bioavailability refers to the extent to which humans and ecological receptors are exposed to contaminants in soil or sediment. The concept of bioavailability has recently piqued the interest of the hazardous waste industry as an important consideration in deciding how much waste to clean up. The rationale is that if contaminants in soil and sediment are not bioavailable, then more contaminant mass can be left in place without creating additional risk. A new NRC report notes that the potential for the consideration of bioavailability to influence decision-making is greatest where certain chemical, environmental, and regulatory factors align. The current use of bioavailability in risk assessment and hazardous waste cleanup regulations is demystified, and acceptable tools and models for bioavailability assessment are discussed and ranked according to seven criteria. Finally, the intimate link between bioavailability and bioremediation is explored. The report concludes with suggestions for moving bioavailability forward in the regulatory arena for both soil and sediment cleanup.

Bioavailability refers to the extent to which humans and ecological receptors are exposed to contaminants in soil or sediment. The concept of bioavailability has recently piqued the interest of the hazardous waste industry as an important consideration in deciding how much waste to clean up. The rationale is that if contaminants in soil and sediment are not bioavailable, then more contaminant mass can be left in place without creating additional risk. A new NRC report notes that the potential for the consideration of bioavailability to influence decision-making is greatest where certain chemical, environmental, and regulatory factors align. The current use of bioavailability in risk assessment and hazardous waste cleanup regulations is demystified, and acceptable tools and models for bioavailability assessment are discussed and ranked according to seven criteria. Finally, the intimate link between bioavailability and bioremediation is explored. The report concludes with suggestions for moving bioavailability forward in the regulatory arena for both soil and sediment cleanup.

This book discusses bioavailability concepts and methods, summarizing the current knowledge on bioavailability science, as well as possible pathways for integrating bioavailability into risk assessment and the regulation of organic chemicals. Divided into 5 parts, it begins with an overview of chemical distribution in soil and sediment, as well as the bioavailability and bioaccumulation of chemicals in plants, soil, invertebrates and vertebrates (including humans). It then focuses on the impact of sorption processes and reviews bioavailability measurement methods. The closing chapters discuss the impact of bioavailability studies on chemical risk assessment, and highlights further research needs. Written by a multi-disciplinary team of authors, it is an essential resource for scientists in academia and industry, students, as well as for authorities.

Bioavailability (the availability to biota) of organic contaminants is a critical issue for DOD installation restoration programs. Reduced availability of contaminants to biodegrading microbial populations frequently is a rate limiting problem in site cleanup of soils, groundwater, and freshwater and marine sediments. Contaminants may interact with soil and sediment particles to create complex residues which are protected from attack by microbial enzymes. Chemical solubility and sorption to surfaces of clay or colloidal organic matter may also alter the availability of contaminants to microorganisms. Mass transfer limitations (e.g., pore diffusion) may limit the rate of biodegradation and hence bioavailability. Slow leaching of contaminants from soils has been a problem in site which have been remediated. Furthermore, physical characteristics of the soil or sediment system may limit transport of bacteria with biodegradation capabilities to the contaminant sites within the porous media.

With its 104 chapters, this Encyclopedia of aquatic ecotoxicology reveals the diversity of issues, problems and challenges that have faced, and are facing today, receiving environments. It also indicates ways by which tools, strategies and future investigations can contribute to correct, minimize, solve and prevent water quality degradation. Structured homogeneously, the chapters convey salient information on historical background, features, characteristics, uses and/or applications of treated topics, often complemented by illustrations and case studies, as well as by conclusions and prospects. This work is most suitable for teaching purposes. Academics, for example, could literally deliver comprehensive lectures to students simply based on chapter outlines and contents. Meet the Authors of the Encyclopedia! Check out 'Meet the Authors' under ADDITIONAL INFORMATION (Right menu).