The prediction of PAHs bioavailability in soils using chemical methods: State of the art and future challenges

• Tipo: Outra Publicação em Revista Científica Internacional
• Data: 2014

Autores

Cachada, A (Autor) Outra; Pereira, R (Autor) FCUP; Ferreira da Silva, EF (Autor) Outra; Duarte, AC (Autor) Outra

Revista

Título: Science of the Total Environment

Vol. 472

Páginas: 463-480

ISSN: 0048-9697

Editora: Elsevier

Indexação

ISI Web of Knowledge - 78 Citações

Scopus - 85 Citações

Classificação Científica

FOS: Ciências exactas e naturais > Ciências da terra e ciências do ambiente

Outras Informações

ID Authenticus: P-008-HTX

DOI: 10.1016/j.scitotenv.2013.11.038

Abstract (EN): The evaluation of the available fraction of hydrophobic organic contaminants (HOCs) is extremely important for assessing their risk to the environment and human health. This available fraction, which can be solubilized and/or easily extracted, is believed to be the most accessible for bioaccumulation, biosorption and/or transformation by organisms. Based on this, two main types of chemical methods have been developed, closely related to the concepts of bioaccessibility and freely available concentrations: non-exhaustive extractions and biomimetic methods. Since bioavailability is species and compound specific, this work focused only in one of the most widespread group of HOCs in soils: polycyclic aromatic hydrocarbons (PAHs). This study aims at producing a state of the art knowledge base on bioavailability and chemical availability of PAHs in soils, clarifying which chemical methods can provide a better prediction of an organism exposure, and which are the most promising ones. Therefore, a review of the processes involved on PAHs availability to microorganisms, earthworms and plants was performed and the outputs given by the different chemical methods were evaluated. The suitability of chemical methods to predict bioavailability of the 16 US EPA PAHs in dissimilar naturally contaminated soils was not yet demonstrated, being especially difficult for high molecular weight compounds. Even though the potential to predict microbial mineralization using non-exhaustive extractions is promising, it will be very difficult to achieve for earthworms and plants, due to the complexity of accumulation mechanisms which are not taken into account by chemical methods. Yet, the existing models could be improved by determining compound, species and site specific parameters. Moreover, chemical availability can be very useful to understand the bioavailability processes and the behavior of PAHs in soils. The inclusion of chemical methods on risk assessment has been suggested and it is promising, despite some methods overpredict risks.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 18