Characteristics, fate, and effects of <i>Helicobacter pylori</i> in municipal wastewater treatment plant

Abstract

<p><i>Helicobacter pylori</i> (<i>H. Pylori</i>) is a highly pathogenic bacterium that can be transmitted through various means, including wastewater, which serves as both a source and sink for <i>H. pylori.</i> In the wastewater treatment process, the exposure risk of <i>H. Pylori</i> escaping through bioaerosols is easily overlooked. In this study, the pollution characteristics and variation patterns of <i>H. Pylori</i> in wastewater, sludge, and air medium were systematically investigated in a typical municipal wastewater treatment plant (MWTP) applying anaerobic-anoxic-aerobic process through long-term sampling. The results indicated a significant reduction of <i>H. Pylori</i> in wastewater and accumulation in excess sludge following the wastewater treatment process. <i>H. Pylori</i> was also detected in bioaerosols due to its escape during wastewater treatment and sludge dewatering. The highest detection concentrations of <i>H. Pylori</i> in the air were found in the sludge dewatering house. O₃, solar radiation, ambient temperature, and wind speed all had negative effects on the relative abundance and respirable proportion of airborne <i>H. pylori</i>. In addition, <i>H. Pylori</i> in bioaerosols had the potential to contaminate the ambient environment and posed a potential health risk to operational workers. This study will help to recognize the pollution of <i>H. Pylori</i> in MWTPs and raise the attention to occupational exposure among MWTP workers.</p>