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, 17 (1)

Evaluation of Bioaerosol Bacterial Components of a Wastewater Treatment Plant Through an Integrate Approach and In Vivo Assessment

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Evaluation of Bioaerosol Bacterial Components of a Wastewater Treatment Plant Through an Integrate Approach and In Vivo Assessment

Erika Bruni et al. Int J Environ Res Public Health.

Abstract

Wastewater carries different pathogenic and non-pathogenic microorganisms that can be dispersed in the surrounding environment. Workers who frequent sewage treatment plants can therefore be exposed to aerosols that contain a high concentration of potentially dangerous biological agents, or they can come into direct contact with contaminated material. This can lead to allergies, infections and occupational health-associated diseases. A characterization of biological risk assessment of bioaerosol exposure is necessary. The aim of this study was to evaluate the application of an interdisciplinary method that combines chemical and biological approaches for the analysis of a bioaerosol derived from a wastewater treatment plant (WWTP) situated in Italy. Sampled filters were analyzed by HPLC-MS/MS spectroscopy that searched for different chemical biomarkers of airborne microorganisms. The analytical quantification was compared to the biological cultural method that revealed an underrated microbial concentration. Furthermore, next generation sequencing analysis was used also to identify the uncultivable species that were not detected by the culture dependent-method. Moreover, the simple animal model Caenorhabditis elegans was used to evaluate the pathogenicity of two isolates-Acinetobacter iwoffii and Micrococcus luteus-that showed multidrug-resistance. This work represents a starting point for the development of a multidisciplinary approach for the validation of bioaerosol exposure on WWTP workplaces.

Keywords: Caenorhabditis elegans; airborne; bacterial bioaerosol; wastewater; worker exposure.

Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
Wastewater treatment plants with the oxidation aeration tanks highlighted by the yellow star.
Figure 2
Figure 2
Number (n°) of total bacterial cell/m3 in the wastewater treatment plant (WWTP). Sampling campaign WWTP_RE1 (first period) and WWTP_RE2 (second period).
Figure 3
Figure 3
Number (°) of total bacterial spores/m3 in the wastewater treatment plant (WWTP). Sampling campaign WWTP_RE1 (first period) and WWTP_RE2 (second period).
Figure 4
Figure 4
Number (n°) of total fungal spores/m3 in the wastewater treatment plant (WWTP). Sampling campaign WWTP_RE1 (first period) and WWTP_RE2 (second period).
Figure 5
Figure 5
Simulation, according to the HYSPLIT model, of the wind trajectory coming from the desert areas of North Africa (16 April 2018 H 12:00).
Figure 6
Figure 6
Most abundant genera (>1%) in WWTP_RE1 and WWTP_RE2 samples (Unid, unidentified).
Figure 7
Figure 7
Cultivable microbial charge derived from the filters of the two subsequent samplings of WWTP_RE1 and WWTP_RE2. (a) Bacteria colony forming unit (CFU)/m3 obtained on NB agar plates by washing the sampled filters. Amounts for fine (PM < 1) and coarse fraction (PM > 1) are reported for each sampling. (b) Fungi CFU/m3 obtained on yeast extract peptone dextrose (YPD) agar plates by washing the sampled filters. Amounts for fine (PM < 1) and coarse fraction (PM > 1) are reported for each sampling. (c) Total amount of collected CFU/m3 of bacteria and fungi in the WWTP_RE1 and WWTP_RE2 samplings.
Figure 8
Figure 8
Effects of M. luteus and A. iwoffii on Caenorhabditis elegans physiology. (a) Kaplan–Meier survival plot of N2 worms fed with A. iwoffii and (b) M. luteus. Infections were performed at 25 °C, and worm mortality was monitored every day. The lifespan of OP50-fed animals is reported as control; n = 60 for each data point of single experiments. Statistical analysis was evaluated by Log-rank (Mantel–Cox) test; asterisks indicate significant differences (*** p < 0.001). (c) Measurement of worm’s body length starting from their hatching on plates that were seeded with the indicated bacteria. Worm length was measured from head to tail at the indicated time points. Statistical analysis was evaluated by a one-way ANOVA with the Bonferroni post-test; asterisks indicate significant differences (ns as non-significant; * p < 0.05; ** p < 0.01; *** p < 0.001).
Figure 9
Figure 9
(a) Average embryos production per worm of M. luteus-, A. iwoffii- and OP50-fed animals. Bars represent the standard deviations. (b) Pharyngeal pumping rate after continued exposure to the indicated bacteria and worms fed with OP50 were used as controls. The contractions were measured for 30 s and determined from the mean of 10 worms for each bacterial strain. (c) Body bend frequency of worms fed with OP50, M. luteus and A. iwoffii from one-day-adult stage. The number of thrashes was measured in a time period of 60 s. Statistical analysis was performed by a one-way ANOVA with the Bonferroni post-test; asterisks indicate significant differences (ns as non-significant; * p < 0.05, ** p < 0.01, *** p < 0.001).

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References

    1. Fröhlich-Nowoisky J., Kampf C.J., Weber B., Huffman J.A., Pöhlker C., Andreae M.O., Lang-Yona N., Burrows S.M., Gunthe S.S., Elbert W., et al. Bioaerosols in the Earth system: Climate, health, and ecosystem interactions. Atmos. Res. 2016;182:346–376. doi: 10.1016/j.atmosres.2016.07.018. - DOI
    1. Bonazza A., De Nuntiis P., Mandrioli P., Sabbioni C. Aerosol Impact on Cultural Heritage: Deterioration Processes and Strategies for Preventive Conservation. In: Tomasi C., Fuzzi S., Kokhanovsky A., editors. Atmospheric Aerosols: Life Cycles and Effects on Air Quality and Climate. Wiley-VCH Verlag GmbH & Co. KGaA; Weinheim, Germany: 2017. pp. 645–670. - DOI
    1. Eduard W., Heederik D., Duchaine C., Green B.J. Bioaerosol exposure assessment in the workplace: The past, present and recent advances. J. Environ. Monit. 2012;14:334–339. doi: 10.1039/c2em10717a. - DOI - PMC - PubMed
    1. Pillai S.D., Ricke S.C. Bioaerosols from municipal and animal wastes: Background and contemporary issues. Can. J. Microbiol. 2002;48:681–696. doi: 10.1139/w02-070. - DOI - PubMed
    1. Vitezova M., Mach P., Vitez T., Losak T. Development of microbial community in the course of composting of garden waste. Acta Univ. Agric. Silvic. Mendel. Brun. 2012;60:225–232. doi: 10.11118/actaun201260030225. - DOI
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