Commercial products for the bioremediation of hydrocarboncontaminated soil: Characteristics and effectiveness

BACKGROUND AND AIMS: Aerobic biodegradation kinetics of hydrocarbons in contaminated soils can be limited by three main factors: i) the low presence of nutrients; ii) the low bioavailability of the contaminants and iii) the reduced presence of hydrocarbon biodegradative capacity in the soil community. To overcome these limiting factors different commercial products have apperead on the market in recent years. The aim of this project is to investigate the chemicho-pysical, biodegradative and evironmental fate featues of twenty commercial products belonging to the three categories. METHODS: Some commercial products are offered as formulations of two or three of the listed categories. These products were characterised and used in different bioremediation strategies to assess their impact on the biodegradation process. Biostimulation, bioaugmentation and the use of surfactant/biosurfactant were evalueted by adding these commercial products. RESULTS: Different proprieties of the commercial formulations were investigated, in particularly the elemental composition (CHNP), the structure of the microbial communities, the interaction with the soil and contaminants (adsorption), the surfactant capacities (critical micelle concentration, emulsification), as well as the fitotoxicity and biodegradability. These information allows to define the effectiveness, efficiency, and environmental compatibility of each product. These data were integrated with the results of microcosm test at laboratory-scale, performed to assess the efficiency of products in enhancing the hydrocarbon biodegradation rate in contaminated soil. CONCLUSION: Product characterisation and microcosm test guide to an effective choice of the product to be used for the treatment of soil contaminated by hydrocarbon mixtures.