Bioavailability of hydrophobic organic contaminants in soils: fundamental concepts and techniques for analysis

Abstract

Summary Soils represent a major sink for organic xenobiotic contaminants in the environment. The degree to which organic chemicals are retained within the soil is controlled by soil properties, such as organic matter, and the physico‐chemical properties of the contaminant. Chemicals which display hydrophobic and lipophilic characteristics, as well as a recalcitrant chemical structure, will be retained within the soil, and depending on the ‘strength’ of the association may persist for long periods of time. This review describes the behaviour of hydrophobic organic contaminants in soils, focusing on the mechanisms controlling interactions between soil and contaminants. The bioavailability of contaminants in soil is also discussed, particularly in relation to contact time with the soil. It considers the degradation of organic contaminants in soil and the mechanisms microbes use to access contaminants. Finally, the review discusses the ‘pros’ and ‘cons’ of chemical and biological techniques available for assessing bioavailability of hydrophobic organic chemicals in soils, highlighting the need to quantify bioavailability by chemical techniques. It concludes by highlighting the need for understanding the interactions between the soil, contaminants and biota which is crucial to understanding the bioavailability of contaminants in soils.

Influences of artificial root exudate components on the behaviors of BDE-28 and BDE-47 in soils: desorption, availability, and biodegradation

“…Sorption and desorption of organic contaminants are fundamental processes controlling their transportation in soils (Tolls 2001). The uptake of organic contaminants was determined by their bioavailability and biotransformation in soils, which have been addressed as the key processes affecting their toxicity to and accumulation in biota (Cui et al 2013;Semple et al 2003). These diverse processes coexist for organic contaminants in soils and influence each other; therefore, a thorough investigation of these processes is necessary in order to comprehensively understand the unique behaviors of organic contaminants in soils.…”

Biodegradação de alcoóis, ftalatos e adipatos em um solo tropical contaminado

“…Os diferentes países do mundo têm se esforçado na identificação de áreas contaminadas, na quantificação de seus impactos sobre a saúde e bem-estar público e na sua reabilitação. [7][8][9][10][11] Um diagnóstico preliminar do Ministério 16 a biodisponibilidade de compostos orgânicos hidrofóbicos, como os ftalatos, é função do grau de adsorção dos mesmos aos minerais e à matéria orgânica do solo. Assim, a biodegradação destes compostos é diferente em solos tropicais e de regiões de climas temperados.…”

Comparison of naphthalene bioavailability determined by whole-cell biosensing and availability determined by extraction with Tenax

“…However, biodegradation of PAHs in the environment is often limited by processes that reduce bioavailability (e.g. their strong tendency to sorb to organic matter (Bosma et al, 1997;Semple et al, 2003)). Hence, we used naphthalene as an analyte with environmental relevance that promised to improve our understanding of PAH bioavailability.…”