Concentrations, Size Distribution, and Community Structure Characteristics of Culturable Airborne Antibiotic-Resistant Bacteria in Xinxiang, Central China

Xu Yan,Jingyuan Ren,Jiahui Ma,Tianning Li,Miao Lei,Dezhi Qiu,Li Guo,Mengjia Cui,Chun Chen,Yunping Han,Xinqing Chen

doi:10.3390/atmos12081077

Abstract

Antimicrobial resistance is considered an important threat to global health and has recently attracted significant attention from the public. In this study, the concentrations and size distribution characteristics of culturable airborne total bacteria (TB) and four antibiotic-resistant bacteria (tetracycline-resistant bacteria (TRB), ciprofloxacin-resistant bacteria (CRB), erythromycin-resistant bacteria (ERB), and ampicillin-resistant bacteria (ARB)) were investigated for approximately one year to explore their variations under different seasons, diurnal periods, and air quality levels. The concentrations of TB and four antibiotic-resistant bacteria in winter and night were higher than during other seasons and diurnal periods. Their maximum concentrations were detected from air under moderate pollution or heavy pollution. PM2.5, PM10, SO2, and NO2 were positively related to TB and four antibiotic-resistant bacteria (p < 0.01), whereas O3 and wind speed were negatively related to them (p < 0.05). The particle size of TB and four antibiotic-resistant bacteria were mainly distributed in stage V (1.1–2.2 µm). Bacillus was the dominant genus of ARB (75.97%) and CRB (25.67%). Staphylococcus and Macrococcus were the dominant genera of TRB (46.05%) and ERB (47.67%), respectively. The opportunistic pathogens of Micrococcus, Sphingomonas, Enterococcus, Rhodococcus, and Stenotrophomonas were also identified. This study provides important references for understanding the threat of bioaerosols to human health.

Highlights

The concentrations of total bacteria (TB), TRB, CRB, ERB, and ARB samples were in the range of 1.11 × 103 –1.29 × 104 CFU/m3, 2.06 × 102 –4.65 × 103 CFU/m3, 5.95 × 102 –4.62 × 103 CFU/m3, 3.13 × 102 –4.41 × 103 CFU/m3, and 2.76 × 102 –6.41 ×
The highest concentrations of TB, TRB, and ERB were detected on 14 January 2018
The results show that one peak appeared at 1.1–2.1 μm, which is consistent with our results, whereas the other peak was at 4.7–7.0 μm [7]

Summary

Introduction

Bioaerosols exist extensively in human living and natural environments, predominantly including bacteria, fungi, archaea, viruses, pollen, and endotoxins [1,2,3]. As an important component of atmospheric particulate matter, bioaerosols play an important role in atmospheric chemistry and climate change [4,5,6,7]. Bacteria are the primary component in bioaerosols, accounting for 80% of the atmospheric microbial components [3]. Exposure to high concentrations of airborne bacteria, pathogenic bacteria, can cause a series of diseases, such as respiratory, digestive system, and cardiovascular diseases [8,9]

Objectives

Methods

Results