Enhanced bioremediation of soil from Tianjin, China, contaminated with polybrominated diethyl ethers.

Abstract

This work aimed to evaluate the effectiveness of nutrients, H2O2, and tourmaline on the bioremediation of fields where the soil was contaminated with polybrominated diethyl ethers (PBDEs). The results showed that 39.2, 38.3, and 48.1 % of total PBDE removal was observed in microcosms with the addition of nutrients, such as NaNO3, NH4Cl, and NH4NO3, respectively, compared to only 15.2 and 5.8 % of PBDE removal from soil with added Aspergillus niger and control soil, respectively, after 50 days of incubation. In addition, 50.8 and 56.5 % of total PBDE removal were observed in microcosms with 0.5 and 1 μL H2O2. The addition of tourmaline increased total PBDE removal to 32.4 %. Significant increases in soil enzymatic activity with PBDE degraders and bacterial communities were observed using polymerase chain reaction (PCR)--denaturing gradient gel electrophoresis (DGGE). These observations suggested that the combination of inorganic nutrients with chemical, mineral, and biological treatment could improve the PBDE removal efficiency. However, the combination of H2O2 and biological treatment processes is the most efficient technology. This combination of technologies would not cause adverse effects on the subsequent bioremediation process. Therefore, this work offers a potential alternative for the remediation of soil contaminated with PBDE pollutants.