Microbial contamination and metabolite exposure assessment during waste and recyclable material collection.

Waste workers are exposed to bioaerosols when handling, lifting and dumping garbage. Bioaerosol exposure has been linked to health problems such as asthma, airway irritant symptoms, infectious, gastrointestinal and skin diseases, and cancer. Our objective was to characterize the exposure of urban collectors and drivers to inhalable bioaerosols and to measured the cytotoxic effect of air samples in order to evaluate their health risk. Personal and ambient air sampling were conducted during the summer of 2019. Workers from 12 waste trucks collecting recyclables, organic waste or compost were evaluated. Bacteria and fungi were cultured, molecular biology methods were used to detect microbial indicators, cytotoxic assays were performed and endotoxins and mycotoxins were quantified. Domestic waste collectors were exposed to concentrations of bacteria and endotoxins above the recommended limits, and Aspergillus section Fumigati was detected at critical concentrations in their breathing zones. Cytotoxic effects were observed in many samples, demonstrating the potential health risk for these workers. This study establishes evidence that waste workers are exposed to microbial health risks during collection. It also demonstrates the relevance of cytotoxic assays in documenting the general toxic risk found in air samples. Our results also suggest that exposures differ depending on the type of waste, job title and discharge/unloading locations.

Settled dust assessment in clinical environment: useful for the evaluation of a wider bioburden spectrum.

The collection and analysis of settled dust samples from indoor environments has become one of several environmental sampling methods used to assess bioburden indoors. The aim of the study was to characterize the bioburden in vacuumed settled dust from 10 Primary Health Care Centers by culture based and molecular methods. Results for bacterial load ranged from 1 to 12 CFU.g-1 of dust and Gram-negative bacteria ranged between 1 to 344 CFU.g-1 of dust. Fungal load ranged from 0 CFU.g-1 of dust to uncountable. Aspergillus section Fumigati was detected in 4 sampling sites where culture base-methods could not identify this section. Mucorales (Rhizopus sp.) was observed on 1 mg/L voriconazole. Three out of 10 settled dust samples were contaminated by mycotoxins. Settled dust sampling coupled with air sampling in a routine way might provide useful information about bioburden exposure.

Stable predictive markers for Phytophthora sojae avirulence genes that impair infection of soybean uncovered by whole genome sequencing of 31 isolates.

BACKGROUND: The interaction between oomycete plant pathogen Phytophthora sojae and soybean is characterized by the presence of avirulence (Avr) genes in P. sojae, which encode for effectors that trigger immune responses and resistance in soybean via corresponding resistance genes (Rps). A recent survey highlighted a rapid diversification of P. sojae Avr genes in soybean fields and the need to deploy new Rps genes. However, the full genetic diversity of P. sojae isolates remains complex and dynamic and is mostly characterized on the basis of phenotypic associations with differential soybean lines. RESULTS: We sequenced the genomes of 31 isolates of P. sojae, representing a large spectrum of the pathotypes found in soybean fields, and compared all the genetic variations associated with seven Avr genes (1a, 1b, 1c, 1d, 1k, 3a, 6) and how the derived haplotypes matched reported phenotypes in 217 interactions. We discovered new variants, copy number variations and some discrepancies with the virulence of previously described isolates with Avr genes, notably with Avr1b and Avr1c. In addition, genomic signatures revealed 11.5% potentially erroneous phenotypes. When these interactions were re-phenotyped, and the Avr genes re-sequenced over time and analyzed for expression, our results showed that genomic signatures alone accurately predicted 99.5% of the interactions. CONCLUSIONS: This comprehensive genomic analysis of seven Avr genes of P. sojae in a population of 31 isolates highlights that genomic signatures can be used as accurate predictors of phenotypes for compatibility with Rps genes in soybean. Our findings also show that spontaneous mutations, often speculated as a source of aberrant phenotypes, did not occur within the confines of our experiments and further suggest that epigenesis or gene silencing do not account alone for previous discordance between genotypes and phenotypes. Furthermore, on the basis of newly identified virulence patterns within Avr1c, our results offer an explanation why Rps1c has failed more rapidly in the field than the reported information on virulence pathotypes.

Increased body fat mass explains the positive association between circulating estradiol and insulin resistance in postmenopausal women.

The relationship between circulating estrogen levels and cardiometabolic risk factors such as insulin resistance is unclear in postmenopausal women. High estradiol (E2) levels have been reported to predict increased risk of type 2 diabetes in this population. We aimed to examine associations among estrogen levels, adiposity measurements, and cardiometabolic risk variables including insulin resistance in postmenopausal women. One hundred-one healthy participants (mean ± SD: age 57 ± 4 yr, BMI 27.9 ± 4.8 kg/m2) were included in the analysis. Fifteen plasma steroids or metabolites were measured by liquid chromatography-tandem mass spectrometry. Insulin sensitivity was assessed with a hyperinsulinemic-euglycemic clamp. Body composition and fat distribution were determined with hydrostatic weighing and computed tomography, respectively. Blood lipids and circulating cytokines were also measured. Circulating E2 was positively correlated with all adiposity indexes ( r = 0.62 to 0.42, P < 0.0001) except waist-to-hip ratio. E2 was positively correlated with VLDL-cholesterol, plasma-, VLDL-, and HDL-triglyceride levels ( r = 0.31 to 0.24, P < 0.02) as well as with hs-CRP and IL-6 ( r = 0.52 and 0.29, P < 0.005) and negatively with HDL-cholesterol, adiponectin, and insulin sensitivity ( r = -0.36 to -0.20, P < 0.02). With adjustments for percent body fat, correlations between E2 and metabolic risk variables were no longer significant. Similar results were observed for circulating estrone (E1) and estrone-sulfate (E1-S) levels. In conclusion, circulating estrogen concentrations are proportional to adipose mass in postmenopausal women, although they remain in the low range. Insulin resistance as well as altered blood lipids and cytokines are observed when circulating estrogen levels are high within that range, but these differences are explained by concomitant variation in total adiposity.

Filters from taxis air conditioning system: A tool to characterize driver's occupational exposure to bioburden?

Bioburden proliferation in filters from air conditioning systems of taxis represents a possible source of occupational exposure. The aim of this study was to determine the occurrence of fungi and bacteria in filters from the air conditioning system of taxis used for patient transportation and to assess the exposure of drivers to bioburden. Filters from the air conditioning systems of 19 taxis and 28 personal vehicles (used as controls) operating in three Portuguese cities including the capital Lisbon, were collected during the winter season. The occurrence and significance of bioburden detected in the different vehicles are reported and discussed in terms of colony-forming units (CFU) per 1 m2 of filter area and by the identification of the most frequently detected fungal isolates based on morphology. Azole-resistant mycobiota, fungal biomass, and molecular detection of Aspergillus species/strains were also determined. Bacterial growth was more prevalent in taxis (63.2%) than in personal vehicles (26.3%), whereas fungal growth was more prevalent in personal vehicles (53.6%) than in taxis (21.1-31.6%). Seven different azole-resistant species were identified in this study in 42.1% taxi filters. Levels of fungal biomass were above the detection limit in 63% taxi filters and in 75% personal vehicle filters. No toxigenic species were detected by molecular analysis in the assessed filters. The results obtained show that bioburden proliferation occurs widely in filters from the air conditioning systems of taxis, including the proliferation of azole-resistant fungal species, suggesting that filters should be replaced more frequently. The use of culture based-methods and molecular tools combined enabled an improved risk characterization in this setting.

Workers' exposure to bioaerosols from three different types of composting facilities.

Composting is a natural dynamic biological process used to valorise putrescible organic matter. The composting process can involve vigorous movements of waste material piles, which release high concentrations of bioaerosols into the surrounding environment. There is a lack of knowledge concerning the dispersal of airborne microorganisms emitted by composting plants (CP) as well as the potential occupational exposure of composting workers. The aim of this study was to investigate the workers exposure to bioaerosols during working activities in three different types of composting facilities (domestic, manure, carcass) using two different quantification methods (cultivation and qPCR) for bacteria and moulds concentrations. As expected, even if there are differences between all CP frameworks, independently of the type of the raw compost used, the production of bioaerosols increases significantly during handling activities. Important concentrations of mesophilic moulds and mesophilic bacteria were noted in the working areas with a respective maximal concentration of 2.3 × 105 CFU/m3 and 1.6 × 105 CFU/m3. A. fumigatus and thermophilic Actinomycetes were also detected in all working areas for the 3 CP. This study emphases the risks for workers to being in contact with aerosolized pathogens such as Mycobacterium and Legionella and more specifically, L. pneumophila. The presence of high concentration of these bacteria in CP suggests a potential occupational health risk. This study may lead to recommendations for the creation of limits for occupational exposure. There is a need for identifying the standards exposure limits to bioaerosols in CP and efficient recommendation for a better protection of workers' health.

Two Related Occupational Cases of Legionella longbeachae Infection, Quebec, Canada.

Two patients with no exposure to gardening compost had related Legionella longbeachae infections in Quebec, Canada. Epidemiologic investigation and laboratory results from patient and soil samples identified the patients' workplace, a metal recycling plant, as the likely source of infection, indicating a need to suspect occupational exposure for L. longbeachae infections.

Comparison of methods to evaluate the fungal biomass in heating, ventilation, and air-conditioning (HVAC) dust.

Heating, ventilation, and air-conditioning (HVAC) systems contain dust that can be contaminated with fungal spores (molds), which may have harmful effects on the respiratory health of the occupants of a building. HVAC cleaning is often based on visual inspection of the quantity of dust, without taking the mold content into account. The purpose of this study is to propose a method to estimate fungal contamination of dust in HVAC systems. Comparisons of different analytical methods were carried out on dust deposited in a controlled-atmosphere exposure chamber. Sixty samples were analyzed using four methods: culture, direct microscopic spore count (DMSC), ß-N-acetylhexosaminidase (NAHA) dosing and qPCR. For each method, the limit of detection, replicability, and repeatability were assessed. The Pearson correlation coefficients between the methods were also evaluated. Depending on the analytical method, mean spore concentrations per 100 cm2 of dust ranged from 10,000 to 682,000. Limits of detection varied from 120 to 217,000 spores/100 cm2. Replicability and repeatability were between 1 and 15%. Pearson correlation coefficients varied from -0.217 to 0.83. The 18S qPCR showed the best sensitivity and precision, as well as the best correlation with the culture method. PCR targets only molds, and a total count of fungal DNA is obtained. Among the methods, mold DNA amplification by qPCR is the method suggested for estimating the fungal content found in dust of HVAC systems.

Assessment of waste workers occupational risk to microbial agents and cytotoxic effects of mixed contaminants present in the air of waste truck cabin and ventilation filters.

Workers in the waste-processing industry are potentially exposed to high concentrations of biological contaminants, leading to respiratory and digestive problems and skin irritations. However, few data on the exposure of waste collection truck (WCT) drivers are available. The goal was to document the microbial risk of the waste collection truck (WCT) workers while in the vehicle cab. Long-period sampling using the truck air filters (CAF) and short time ambient air sampling in the cab were used. The potential release of microbial particles from CAFs was also investigated since it could contribute to the microbial load of the cabin air. A combination of analytical methods also helped assess the complex mixture of the biological agents. Aspergillus sections Fumigati and Flavi, E. coli, Enterobacter spp. and Legionella spp. were detected in the CAF of trucks collecting three types of waste. The highest levels of bacteria and fungi were found in the CAF from organic WCT. The highest endotoxin concentrations in CAF were 300 EU/cm2. Most of the CAF showed cytotoxic effects on both lung cells and hepatocytes. Only one mycotoxin was detected in a CAF. The maximal concentrations in the ambient WCT air varied according to the type of waste collected. The highest proportion (84%) of the air samples without cytotoxic effects on the lungs cells was for the recyclable material WCTs. The results revealed the potential microbial risk to workers from a complex mixture of bio-contaminants in the cabs of vehicles collecting all types of waste. The sustained cytotoxic effect indicates the potential adverse health-related impact of mixed contaminants (biological and non-biological) for the workers. Overall, this study highlights the benefits of using complementary sampling strategy and combined analytical methods for a the assessment of the microbial risk in work environments and the need to implement protective measures for the workers.Implications: Exposure to microbial agents is a well-known occupational hazard in the waste management sector. No previous study had evaluated the cytotoxicity of ambient air and ventilation filters to document worker exposure to a combination of contaminants during waste collection. This research confirms the usefulness of ventilation filters for long-term characterization of exposure to infectious agents, azole-resistant fungi, coliform bacteria and mycotoxin. Overall, this study highlights the importance of using several sampling and analysis methods for a comprehensive assessment of microbial risk in work environments, as well as the need to implement appropriate protective measures for collection workers.

Complementary sampling strategy and combined analytical methods are helpful in risk assessment.Air filter analysis (long-term sampling) assesses the presence of airborne biological contaminants over a long period.The type of waste collected influences the microbiological hazard of the workers.Waste collection workers are potentially exposed to infectious and mycotoxin-producing fungi.Cytotoxic assays revealed that waste collection workers are potentially.

Measurement of endotoxins in bioaerosols at workplace: a critical review of literature and a standardization issue.

Endotoxins are lipopolysaccharides found in the outer membrane of most Gram-negative bacteria and cyanobacteria. Worker exposure to endotoxins has been shown in a number of work situations and is associated with both respiratory and systemic pathologies. The lack of an occupational exposure limit is mainly due to the absence of a standard protocol at the international level for sampling and analyzing airborne endotoxins. The bibliographic review in this article takes an exhaustive look at the current knowledge on measuring airborne endotoxins. It shows that, despite several reference documents at the international level, the methods used to measure endotoxin exposure differ considerably from one laboratory to another. Standardization is necessary to reduce interlaboratory variability and, ultimately, to improve the use of interstudy data. The bibliographic review presents the current status of standardization for airborne endotoxin measurement methods in the workplace and summarizes areas for further research. This article is both a reference document for all operators wishing to use such methods and a working document to build international consensus around the measurement of airborne endotoxins.

Determination of blood:air, urine:air and plasma:air partition coefficients of selected microbial volatile organic compounds.

Partition coefficients (PCs) are essential parameters for understanding the toxicokinetics of chemicals in the human body since they are used in the description of different processes of absorption, distribution, and excretion in physiologically based pharmacokinetic (PBPK) models used in chemical exposure and risk assessment. The goal of this study was to determine urine:air, blood:air and plasma:air partition coefficients (PCs) of microbial volatile organic compounds (mVOCs) previously selected as having high potential as biomarkers of indoor mold exposure. To achieve this goal, the vial-equilibration technique was used, and quantification was performed using headspace gas chromatography tandem mass spectrometry (HS-GC-MS/MS) analysis. Matrix:air PCs of 19 different mVOCs have been successfully determined and their values ranged between 14 and 3586 for urine:air, 78 and 4721 for blood:air and 64 and 5604 for plasma:air PCs. Water:air PCs were also determined, and their values varied between 16 and 2210, showing a good correlation with urine:air PCs for 17 compounds of the selected mVOCs (R2 = 0.97, slope close to unity) indicating that water:air PCs below 103 may be a good surrogate for urine:air PCs. All studied mVOCs have high blood:air PCs (greater than 78) indicating strong pulmonary uptake. Due to their high blood:urine PCs, some mVOCs may be more easily measured in blood than in urine. This work is an important preliminary step toward the use of mVOCs as potential biomarkers of indoor mold exposure. The data obtained in this study will help to determine the most appropriate matrix to use in this biomonitoring approach and will eventually facilitate the development of PBPK models for these chemicals.

A new headspace solid-phase microextraction coupled with gas chromatography-tandem mass spectrometry method for the simultaneous quantification of 21 microbial volatile organic compounds in urine and blood.

Mold growth can cause the development of several metabolites including microbial volatile organic compounds (mVOCs). These latter may be considered as potential biomarkers of fungal presence and have been detected in human biological matrices such as urine and blood. Exposure to molds and their metabolites (e.g., mVOCs, mycotoxins) in occupational settings, is responsible for several health effects. Thus, this exposure cannot be neglected and must be evaluated. Herein, a method has been developed to quantify 21 mVOCs in urine and human blood by headspace solid phase micro-extraction (HS-SPME) coupled with gas chromatography-triple quadrupole mass spectrometry (GC-MS/MS). The parameters influencing the extraction process, such as the type of fiber, the incubation and extraction time and temperature and the desorption time, have been optimized to ensure better mVOCs extraction. The developed method showed good linearity over the concentration range of the compounds (R2 ˃ 0.995) for all the mVOCs in all the matrices. The low limits of detection (LOD) ranging from 0.7 to 417 ng/L in urine and from 1 to 507 ng/L in blood, make the developed methods sensitive and effective for biomonitoring of exposure at low levels. Recoveries, at low and high concentrations, were between 87% and 120% in urine and between 83% and 118% in blood. The repeatability and the intermediate precision in terms of coefficients of variation (CV%) was lower than 13% and 8.58% respectively for all compounds in all matrices. These values show satisfactory accuracy and precision of the developed method. Thus, this practical, simple, and sensitive method is well suited for the simultaneous quantification of target mVOCs.

Tomato brown rugose fruit virus: An emerging and rapidly spreading plant RNA virus that threatens tomato production worldwide.

Tomato brown rugose fruit virus (ToBRFV) is an emerging and rapidly spreading RNA virus that infects tomato and pepper, with tomato as the primary host. The virus causes severe crop losses and threatens tomato production worldwide. ToBRFV was discovered in greenhouse tomato plants grown in Jordan in spring 2015 and its first outbreak was traced back to 2014 in Israel. To date, the virus has been reported in at least 35 countries across four continents in the world. ToBRFV is transmitted mainly via contaminated seeds and mechanical contact (such as through standard horticultural practices). Given the global nature of the seed production and distribution chain, and ToBRFV's seed transmissibility, the extent of its spread is probably more severe than has been disclosed. ToBRFV can break down genetic resistance to tobamoviruses conferred by R genes Tm-1, Tm-2, and Tm-22 in tomato and L1 and L2 alleles in pepper. Currently, no commercial ToBRFV-resistant tomato cultivars are available. Integrated pest management-based measures such as rotation, eradication of infected plants, disinfection of seeds, and chemical treatment of contaminated greenhouses have achieved very limited success. The generation and application of attenuated variants may be a fast and effective approach to protect greenhouse tomato against ToBRFV. Long-term sustainable control will rely on the development of novel genetic resistance and resistant cultivars, which represents the most effective and environment-friendly strategy for pathogen control. TAXONOMY: Tomato brown rugose fruit virus belongs to the genus Tobamovirus, in the family Virgaviridae. The genus also includes several economically important viruses such as Tobacco mosaic virus and Tomato mosaic virus. GENOME AND VIRION: The ToBRFV genome is a single-stranded, positive-sense RNA of approximately 6.4 kb, encoding four open reading frames. The viral genomic RNA is encapsidated into virions that are rod-shaped and about 300 nm long and 18 nm in diameter. Tobamovirus virions are considered extremely stable and can survive in plant debris or on seed surfaces for long periods of time. DISEASE SYMPTOMS: Leaves, particularly young leaves, of tomato plants infected by ToBRFV exhibit mild to severe mosaic symptoms with dark green bulges, narrowness, and deformation. The peduncles and calyces often become necrotic and fail to produce fruit. Yellow blotches, brown or black spots, and rugose wrinkles appear on tomato fruits. In pepper plants, ToBRFV infection results in puckering and yellow mottling on leaves with stunted growth of young seedlings and small yellow to brown rugose dots and necrotic blotches on fruits.

Validation of the criteria for initiating the cleaning of heating, ventilation, and air-conditioning (HVAC) ductwork under real conditions.

Dust accumulation in the components of heating, ventilation, and air-conditioning (HVAC) systems is a potential source of contaminants. To date, very little information is available on recognized methods for assessing dust buildup in these systems. The few existing methods are either objective in nature, involving numerical values, or subjective in nature, based on experts' judgments. An earlier project aimed at assessing different methods of sampling dust in ducts was carried out in the laboratories of the Institut de recherche Robert-Sauvé en santé et en sécurité du travail (IRSST). This laboratory study showed that all the sampling methods were practicable, provided that a specific surface-dust cleaning initiation criterion was used for each method. However, these conclusions were reached on the basis of ideal conditions in a laboratory using a reference dust. The objective of this present study was to validate these laboratory results in the field. To this end, the laboratory sampling templates were replicated in real ducts and the three sampling methods (the IRSST method, the method of the U.S. organization National Air Duct Cleaner Association [NADCA] and that of the French organization Association pour la Prévention et l'Étude de la Contamination [ASPEC]) were used simultaneously in a statistically representative number of systems. The air return and supply ducts were also compared. Cleaning initiation criteria under real conditions were found to be 6.0 mg/100 cm(2) using the IRSST method, 2.0 mg/100 cm(2) using the NADCA method, and 23 mg/100 cm(2) using the ASPEC method. In the laboratory study, the criteria using the same methods were 6.0 for the IRSST method, 2.0 for the NADCA method, and 3.0 for the ASPEC method. The laboratory criteria for the IRSST and NADCA methods were therefore validated in the field. The ASPEC criterion was the only one to change. The ASPEC method therefore allows for the most accurate evaluation of dust accumulation in HVAC ductwork. We therefore recommend using the latter method to objectively assess dust accumulation levels in HVAC ductwork.

Social class considerations in outdoor leadership education.

This chapter considers outdoor leadership in higher education with specific consideration as to how upper- and middle-class values continue to influence accepted norms and assumptions related to skill development and leadership learning. Suggested approaches to make outdoor programs more class-conscious and inclusive are provided.

Evaluation of Dietary Assessment Tools Used in Bariatric Population.

Severe obesity is associated with major health issues and bariatric surgery is still the only treatment to offer significant and durable weight loss. Assessment of dietary intakes is an important component of the bariatric surgery process. OBJECTIVE: To document the dietary assessment tools that have been used with patients targeted for bariatric surgery and patients who had bariatric surgery and explore the extent to which these tools have been validated. METHODS: A literature search was conducted to identify studies that used a dietary assessment tool with patients targeted for bariatric surgery or who had bariatric surgery. RESULTS: 108 studies were included. Among all studies included, 27 used a dietary assessment tool that had been validated either as part of the study per se (n = 11) or in a previous study (n = 16). Every tool validated per se in the cited studies was validated among a bariatric population, while none of the tools validated in previous studies were validated in this population. CONCLUSION: Few studies in bariatric populations used a dietary assessment tool that had been validated in this population. Additional studies are needed to develop valid and robust dietary assessment tools to improve the quality of nutritional studies among bariatric patients.

Evaluation of bacterial contamination and control methods in soluble metalworking fluids.

In the United States, 1.2 million workers are exposed to metalworking fluids. During operations, aerosols are produced and airborne contaminants can be inhaled. Although biocides are used to control the bacterial content of metalworking fluids, they can create health-related problems, and their efficiency remains to be proved. The objectives of this project were (1) to verify whether rigorous cleaning according to a standard protocol could reduce microbial contamination and (2) whether the use of biocides with different spectra could reduce the bacterial population. Four similar machines producing similar components were evaluated; a specific treatment was applied to each machine. The machine used as a control (1) was thoroughly cleaned prior to sampling, (2) did not undergo any major cleaning afterward, and (3) was operated without the use of any biocide. A major cleaning is a protocol described and recommended by the fluid manufacturer and was performed on the three other machines, two of which were subsequently treated with biocides weekly. Fluid samples from the four lathes were collected weekly during a 6-month period, and total bacterial and cultivable Gram-negative bacteria were analyzed for each sample. Major cleaning of the machines (120-4) did not significantly reduce the concentration of bacteria in the cutting fluids when compared with the control machine (120-3), which had not undergone major cleaning. The concentrations of total bacteria were in the 10(6) CFU/mL range for these two lathes; however, a reduction in the total number of fluid changes was observed for this machine. Bacterial flora in the cutting fluids was significantly controlled with the use of biocides. Bacteria concentrations were in the 10(3)-10(5) CFU/mL range for the lathes with the use of biocides. Since thorough cleaning is insufficient and biocides are recognized as being responsible for some worker health problems, other avenues for controlling bacterial flora in cutting fluids should be evaluated to reduce worker exposure to their bacterial contaminants.

Draft Genome Sequences of Hazelnut-Associated Pseudomonas Strains Isolated in Ontario, Canada.

Two Pseudomonas strains (H346-M and H346-S) were isolated from hazelnut trees showing symptoms of shoot dieback and necrosis. The draft genome sequences of H346-M and H346-S consist of 66 and 51 contigs, respectively, with total sizes of 5,693,988 and 5,889,925 bp and 4,885 and 5,045 protein-coding sequences, respectively.

Are workers from waste sorting industry really protected by wearing Filtering Respiratory Protective Devices? The gap between the myth and reality.

One of the solutions for decreasing the workers' exposure to bioburden is the use of Filtering Respiratory Protective Devices (FRPD). As such it is important to determine whether these devices are fulfilling their protective role. This is the basis of the current study, aimed at characterizing bioburden retained by 120 FRPD (both in interior layers and in exhalation valves) through culture based-methods and molecular tools and also via analysis of antifungal resistance and mycotoxins profile. Our results show that Gram - Bacteria are present at a higher prevalence than total bacteria in both matrixes. Regarding fungal identification, Chrysonilia sitophila presented the highest prevalence on interior layers (55.1% on malt extract agar (MEA) supplemented with chloramphenicol (0.05%); 59.6% on dichloran-glycerol agar (DG18)), whereas on exhalation valves Aspergillus sp. presented the highest prevalence on MEA (6.8%) and C. sitophila on DG18 (36.3%). Among Aspergillus genera, section Fumigati was the one with the highest prevalence in both matrices. Aspergillus sp. was the most prevalent on exhalation valves (75.0% ITRA) in the screening of azole resistance. Fumigati section was the most abundant Aspergillus sp. detected on the interior layers (33.33%, 40 samples out of 120) and on the exhalation valves (1.66%, 2 samples out of 120). The interior layers and exhalation valves from workers with more waste contact showed an increased exposure to bioburden. This study showed that FRPD can have high levels of bioburden, toxigenic fungal strains and Aspergillus sections with reduced susceptibility to the tested azoles and can be used as a passive sampling method since it mimics the results obtained by active methods in previous studies. The gathered information will be useful to prioritize multiple interventions on workers' education or even on FRPD replacement frequency.