Cytotoxic and Inflammatory Potential of Air Samples from Occupational Settings with Exposure to Organic Dust

Abstract

Organic dust and related microbial exposures are the main inducers of several respiratory symptoms. Occupational exposure to organic dust is very common and has been reported in diverse settings. In vitro tests using relevant cell cultures can be very useful for characterizing the toxicity of complex mixtures present in the air of occupational environments such as organic dust. In this study, the cell viability and the inflammatory response, as measured by the production of pro-inflammatory cytokines tumor necrosis factor-α (TNFα) and interleukin-1 β (IL-1β), were determined in human macrophages derived from THP-1 monocytic cells. These cells were exposed to air samples from five occupational settings known to possess high levels of contamination of organic dust: poultry and swine feed industries, waste sorting, poultry production and slaughterhouses. Additionally, fungi and particle contamination of those settings was studied to better characterize the organic dust composition. All air samples collected from the assessed workplaces caused both cytotoxic and pro-inflammatory effects. The highest responses were observed in the feed industry, particularly in swine feed production. This study emphasizes the importance of measuring the organic dust/mixture effects in occupational settings and suggests that differences in the organic dust content may result in differences in health effects for exposed workers.

A Novel Multi-Approach Protocol for the Characterization of Occupational Exposure to Organic Dust—Swine Production Case Study

“…Furthermore, particulate matter can be the vehicle for the bioburden present in swine farms, reaching workers respiratory systems and, consequently, enhancing the occupational exposure of swine workers to organic dust [ 9 ]. Therefore, microorganisms adhering to particulate matter, along with coexisting gases and toxins are a general cause of concern regarding co-exposure to several risk factors and possible additive and synergistic health effects [ 20 , 30 ]. This scenario reinforces the theory that occupational exposure is rarely associated with a single factor, since it is commonly a combination of several risk factors [ 31 ].…”

“…Furthermore, the NGS is a qualitative method, and to get a better understanding of the bioburden exposure, the concentration must be assessed using culture-based methods and molecular biology methods such as qPCR [ 54 ]. This approach will allow: by using culture-based methods to obtain information about the infection potential of the bioburden present [ 58 ] and comparing quantitative information with guidelines; by applying molecular tools to target specific species indicators of harmful bioburden and to overcome some culture-based methods constraints [ 30 ].…”

Dust at Various Workplaces—Microbiological and Toxicological Threats

“…), and viable and non-viable macro- and microorganisms with the substances they release (including endotoxins, glucans, mycotoxins, peptidoglycans, enzymes, volatile organic compounds, etc. ), making dust a major source of harmful biological agents [ 4 ]. The toxic effect of dust collected both inside and outside of buildings may depend on the components present in the dust, particularly its organic fraction, including microorganisms, which have great importance [ 3 ].…”

Bioaerosols and Health: Current Knowledge and Gaps in the Field of Waste Management

“…Moreover, the combined effects of biological agents (such as endotoxin and specific allergens) should not be ruled out. Neither should interactive effects between bioaerosols and chemical hazards such as ammonia and volatile organic compounds (Viegas et al, 2017). These points highlight potential differences in response to an environmental indicator depending on the occupational sector (e.g., differences in response to endotoxin exposure in pig farming versus paper and cardboard recycling depending on other associated air pollutants).…”