Living with detergents: pyrosequencing-based assessment of bacterial community structures in soils subjected for decades to contamination by detergents

Although detergents are major environmental pollutants for soil and water, their impact in bacterial community structures has not been addressed. We compared the bacterial community structures as well as several edaphic parameters between severely detergent-contaminated soils and non-contaminated soils in the State of Yucatan, Mexico. The results indicate that sodium concentration, salinity, and electrical conductivity were significantly higher in contaminated samples, and that this correlates with different bacterial community structures. The most important differences were that (i) samples with detergent presented a lower species richness; (ii) Proteobacteria was the most abundant phylum in soils with detergent, while Actinobacteria and Acidobacteria were the most abundant phyla in soils without detergent; (iii) Rhodomicrobium, Hydrogenophaga, and Thiobacillus were the most abundant genera in soils with detergent, while Acidobacteria dominated soils without detergent. With the continual increase of the human population without access to a proper disposal of waste waters, these modifications may contribute to bringing about changes in the ecological parameters of the region.