Temperature-driven alterations in bacterial community responses to decabromodiphenyl ether (BDE-209) contamination in soil microcosms

Abstract

Polybrominated diphenyl ethers (PBDEs) are organic pollutants that pose a threat to natural environments, and their sensitivity can be influenced by various factors, including temperature in real-world environment. Achieving an understanding of how microorganisms respond to PBDEs at various temperatures is crucial for assessing ecological risks or identifying potential degraders. For this study, microcosms were established with or without the addition of 10 mg kg⁻¹ decabromodiphenyl ether (BDE-209) and then incubated at four temperatures—4 °C, 15 °C, 25 °C, and 37 °C—for a period of 180 days. The results indicated that BDE-209 debromination rates decreased in the following sequence: 15 °C, 25 °C, 37 °C, 4 °C. Temperature made a vital role in the diversity, composition, and potential degrading bacteria of BDE-209 debromination. When incubated at 4 °C, 15 °C and 25 °C, BDE-209 substantially reduced the network complexity, highlighting the PBDEs-associated risks in low and moderate temperature microcosms. In contrast, the incorporation of BDE-209 was beneficial for community characterization and networking at 37 °C. The Random forest model pinpointed specific taxa that could potentially be associated with PBDEs debromination at various incubation temperatures. These results revealed contrasting effects of PBDEs on bacterial communities at various temperatures, thus attention should be paid to the impact of PBDEs on soil ecology in real environmental conditions.