Survival of Microorganisms on Filtering Respiratory Protective Devices Used at Agricultural Facilities.

Anita Jachowicz,Justyna Szulc,Beata Gutarowska,Katarzyna Majchrzycka,Małgorzata Okrasa

doi:10.3390/ijerph16162819

Abstract

Bioaerosol is a threat at workplaces, therefore the selection and safe use of filtering facepiece respirators (FFRs) is important in preventive activities. The aim of the study was to assess the survival of microorganisms on materials used for FFRs construction. The parameters for microorganism growth under model conditions were described using the Gompertz equation, model verification was also carried out using FFRs at the farmers’ workplaces. We found that the factors determining a high survival of microorganisms were as follows: moisture corresponding to the conditions of use and storage of FFRs at workplaces, the presence of sweat and organic dust; inorganic dust and addition of biocide in nonwovens limited the growth of microorganisms, resulting in a shortening of the stationary growth phase and decreased cell numbers (5–6 log). Dust concentration at workplaces was higher than EU occupational exposure limit values and WHO recommendations for airborne particulate matter. Microbial contaminations of the air (103–104 CFU/m3), settled dust (104–106 CFU/g) and FFRs (105 CFU/4cm2) during the grain harvest were high, the main contamination being bacteria (actinomycetes, Pseudomonas fluorescens) and xerophilic fungi. A high correlation was found between the number of microorganisms and the weight of dust on FFRs (R2 = 0.93–0.96).

Highlights

The main group of harmful biological factors occurring in workplaces are allergenic and toxic agents forming bioaerosols
We observed that B. subtilis, E. coli bacteria and C. albicans yeast died the fastest and to the greatest extent on the nonwovens with biocide and cement plant dust
The moisture content of the material and the presence of organic dust are the factors that determine the high survival rate of microorganisms on filtering materials used in filtering facepiece respirators (FFRs)

Summary

Introduction

The main group of harmful biological factors occurring in workplaces are allergenic and toxic agents forming bioaerosols. After entering the respiratory system, these factors can cause irritative, toxic, allergic, carcinogenic or fibrotic reactions, resulting in diseases such as chronic obstructive lung disease, bronchial asthma, chronic bronchitis, bronchial hyperresponsiveness and organic dust toxic syndrome. They can irritate mucous membranes, skin and conjunctivae [4,5]. It is probable that high-throughput sequencing technology will detect a higher number of harmful biological agents in other workplaces as well

Objectives

Methods

Results

Discussion

Conclusion