Microbial Exposure Assessment in Sawmill, Livestock Feed Industry, and Metal Working Fluids Handling Industry

Abstract

ObjectivesThe objective of this study is to investigate the distribution patterns and exposure concentrations of bioaerosols in industries suspected to have high levels of bioaerosol exposure.MethodsWe selected 11 plants including 3 livestock feed plants (LF industry), 3 metal working fluids handling plants (MWFs industry), and 5 sawmills and measured total airborne bacteria, fungi, endotoxins, as well as dust. Airborne bacteria and fungi were measured with one stage impactor, six stage cascade impactor, and gelatin filters. Endotoxins were measured with polycarbonate filters.ResultsThe geometric means (GM) of the airborne concentrations of bacteria, fungi, and endotoxins were 1,864, 2,252 CFU/m3, and 31.5 EU/m3, respectively at the sawmills, followed by the LF industry (535, 585 CFU/m3, and 22.0 EU/m3) and MWFs industry (258, 331 CFU/m3, and 8.7 EU/m3). These concentrations by industry type were significantly statistically different (p < 0.01). The ratio of indoor to outdoor concentration was 6.2, 1.9, 3.2, and 3.2 for bacteria, fungi, endotoxins, and dust in the LF industry, 5.0, 0.9, 2.3, and 12.5 in the MWFs industry, and 3.7, 4.1, 3.3, and 9.7 in sawmills. The respiratory fractions of bioaerosols were differentiated by bioaerosol types and industry types: the respiratory fraction of bacteria in the LF industry, MWF industry, and sawmills was 59.4%, 72.0%, and 57.7%, respectively, and that of fungi was 77.3%, 89.5%, and 83.7% in the same order.ConclusionWe found that bioaerosol concentration was the highest in sawmills, followed by LF industry facilities and MWFs industry facilities. The indoor/outdoor ratio of microorganisms was larger than 1 and respiratory fraction of microorganisms was more than 50% of the total microorganism concentrations which might penetrate respiratory tract easily. All these findings suggest that bioaerosol in the surveyed industries should be controlled to prevent worker respiratory diseases.

Non-culturable bioaerosols in indoor settings: Impact on health and molecular approaches for detection

“…High Swine barns 10 5 (Chang et al, 2001;Nehme et al, 2008), 10 4 to 10 8 (Lee et al, 2006b;Verreault et al, 2010) 10 7 to 10 8 (Nehme et al, 2008), 10 7 (Hong et al, 2012), 10 6 to 10 8 (Verreault et al, 2010) 10 6 to 10 8 (Nehme et al, 2009) Dairy barns 10 4 to 10 6 (Duchaine et al, 1999), 10 Poultry and turkey barns 10 1 to 10 6 (Martin and Jackel, 2011), 10 3 (Oppliger et al, 2008), 10 2 to 10 6 (Lawniczek-Walczyk et al, 2013), 10 5 (Fallschissel et al, 2010) 10 3 (Nonnenmann et al, 2010), 10 8 (Oppliger et al, 2008) 10 4 to 10 6 (Just et al, 2013) Peat moss factories 10 3 to 10 5 (Meriaux et al, 2006a;Meriaux et al, 2006b) N/A N/A Wastewater treatment plants 10 3 to 10 4 (Bauer et al, 2002), 10 1 to 10 5 (Laitinen et al, 1994), 0 to 10 3 (Lee et al, 2006a), 10 2 to 10 3 Machining industries 10 1 to 10 3 (Gilbert et al, 2010c), 10 1 to 10 4 (Park et al, 2010), 10 1 to 10 2 N/A N/A Forest product industries 10 2 to 10 4 (Park et al, 2010), 10 2 to 10 5 (Duchaine et al, 2000) N/A N/A Subway station 0 to 10 3 (Dybwad et al, 2014), 10 1 to 10 2 (Kim et al, 2011) N/A N/A Low Schools and daycares 10 1 to 10 3 (Lignell et al, 2005) N/A N/A Homes 10 2 to 10 3 (Frankel et al, 2012), 10 3 (Bouillard et al, 2006) Biodiversity (Adams et al, 2014) N/A Offices 10 1 to 10 3 (Golofit-Szymczak and Gorny, 2010), 10 2 (Tsai and.Macher, 2005), 10 0 to 10 3 (Bholah and Subratty, 2002), 10 1 to 10 2 (Bonetta et al, 2010), 10 1 to 10 3 (Bouillard et al, 2005), 10 1 to 10 2 (Tham and. Zuraimi, 2005), 10 3 to 10 4 (Lis et al, 2004), 10 2 to 10 3 (Sessa et al, 2002), 10 1 to 10 2…”

Microbial Occupational Exposure Assessments in Sawmills—A Review

“…From the selected studies (N = 23), 15 were conducted in the Europe, namely 5 in Norway [29,[36][37][38][39], 4 in Poland [8,[40][41][42], 2 in Switzerland [43,44], 2 in Croatia [45,46], 1 in Finland [47], 1 in Italy [48], and 1 in France [30]. Five studies from Canada [49][50][51][52][53], 1 from Korea [54], and 1 from Iran [55] were also analyzed. The majority of studies (15 out of 23-65.2%) analyzed environmental samples from small and medium size sawmills [18,28,[36][37][38][39][40][41][42][43][44][45][46][47][48][49]51,52], 2 studies (8.7%) were performed in industrial sawmills [29,39], 2 studies (8.7%) in plywood hardwood processing companies [53], 1 (4.4%) in a manufacturing industry [51], 1 (4.4%) in carpentries [48], 1 (4.4%) in pellet p...…”

“…The most used sampling method was air sampling (19 out of 23-82.6%) [18,29,[36][37][38][39][40]43,44,46,47,[49][50][51][52][53][54][55]. Several studies used more than one active sampling method (8 out of 23-34.8%).…”

“…Several studies used more than one active sampling method (8 out of 23-34.8%). Air collection through impaction was used in 16 studies (69.6%) [8,40,[42][43][44][45][46]49,50,[52][53][54][55], followed by filter air sampling in 11 studies (47.8%) [28,29,37,38,41,44,46,48,50,53,54], while 5 studies (21.7%) used the impingement method [29,47,49,50,52].…”

On the interpretation of bioaerosol exposure measurements and impacts on health

“…This suggests that a protective adaptation was acquired due to long-term exposure (Bønløkke et al 2012a). Workplaces such as wastewater treatment plants and metal-working workshops have also received attention regarding workers' exposure to bioaerosols (Niazi et al 2015;Park, Park, and Lee 2010;Teixeira et al 2016;Uhrbrand et al 2017;Veillette et al 2004). The majority of work-environment exposure studies focused on the characterization and quantification of the microbial content in bioaerosols.…”