Abstract

Bioremediation in Antarctic Soils

Hugo E de Jesus, Raquel S Peixoto and Alexandre S Rosado

With the increase of human activities in cold environments, the risk of oil spill has become higher due the necessity of energy generation using oils. Several accidents were related in Arctic and Antarctic involving greatcontaminated areas and chronically levels of contamination. Despite that, Antarctic continent present peculiar characteristics and need to be analyzed separately due to geographic, physic and topologic properties, beyond different proposes of human activities in Antarctic continent. In Antarctic, the main occupations are permanent scientific and military stations and most of them are in activity during whole year. Several studies evaluating the potential of biodegradation were performed using Antarctic soils and the results show promising, however, there is no works about bioremediation process in soils from the core of the continent, only from the shore regions. Antarctic continent present a diverse microbial community able to degrade oils even in extreme conditions, being the most found strains belonging to genera Rhodococcus, Acinetobacter, Sphingomonas, Pseudomonas, Stenotrophomonas, Pedobacter and Brevundimonas. In this regard, bioremediation treatments are indicated to promote a sustainable low cost efficient recovery, that need to be performed as soon as possible after the spill to improve this efficiency. Moreover, in Antarctic environment is necessary to take in account the physical characteristics of the soil, environmental conditions as temperature, water availability, nutrients, season of the year and freeze-thaw cycles. In this sense, activities of maintenance like refueling, cleanup of oil tanks and transport of oils could be made in the winter or near the winter period, as snow can serve as a physic barer containing the contaminant. Besides, bioremediation application could be made preferentially in the summer, due the higher temperature, but after the thaw period, once the unfrozen ice can spread the oil to more sensitive regions and also the nutrients added. This paper proposes an unprecedented review about bioremediation process exclusive to Antarctic soils, and provide necessary knowledge to consolidation of the bioremediation in Antarctic environment, besides suggesting applying strategies. The need to previously study the area to be treated, considering as many abiotic factors as possible, to indicate the best treatment strategy, is even more necessary in Antarctic environments.