Fungi spores dimension matters in health effects: a methodology for more detail fungi exposure assessment

Health effects resulting from dust inhalation in occupational environments may be more strongly associated with specific microbial components, such as fungi, than to the particles. The aim of the present study is to characterize the occupational exposure to the fungal burden in four different occupational settings (two feed industries, one poultry and one waste sorting industry), presenting results from two air sampling methods – the impinger collector and the use of filters. In addition, the equipment used for the filter sampling method allowed a more accurate characterization regarding the dimension of the collected fungal particles (less than 2.5 μm size). Air samples of 300L were collected using the impinger Coriolis μ air sampler. Simultaneously, the aerosol monitor (DustTrak II model 8532, TSI®) allowed assessing viable microbiological material below the 2.5 μm size. After sampling, filters were immersed in 300 mL of sterilized distilled water and agitated for 30 min at 100 rpm. 150 μl from the sterilized distilled water were subsequently spread onto malt extract agar (2%) with chloramphenicol (0.05 g/L). All plates were incubated at 27.5 ºC during 5–7 days. With the impinger method, the fungal load ranged from 0 to 413 CFU.m-3 and with the filter method, ranged from 0 to 64 CFU.m-3. In one feed industry, Penicillium genus was the most frequently found genus (66.7%) using the impinger method and three more fungi species/genera/complex were found. The filter assay allowed the detection of only two species/genera/complex in the same industry. In the other feed industry, Cladosporium sp. was the most found (33.3%) with impinger method and three more species/genera/complex were also found. Through the filter assay four fungi species/genera/complex were found. In the assessed poultry, Rhyzopus sp. was the most frequently detected (61.2%) and more three species/genera/complex were isolated. Through the filter assay, only two fungal species/genera/complex were found. In the waste sorting industry Penicillium sp. was the most prevalent (73.6%) with the impinger method, being isolated two more different fungi species/genera/complex. Through the filter assay only Penicillium sp. was found. A more precise determination of occupational fungal exposure was ensured, since it was possible to obtain information regarding not only the characterization of fungal contamination (impinger method), but also the size of dust particles, and viable fungal particles, that can reach the worker ́s respiratory tract (filters method). Both methods should be used in parallel to enrich discussion regarding potential health effects of occupational exposure to fungi.

Task-based approach used on surfaces sampling strategy definition: the case of antineoplastic occupational exposure

Task-based approach implicates identifying all the tasks developed in each workplace aiming to refine the exposure characterization. The starting point of this approach is the recognition that only through a more detailed and comprehensive understanding of tasks is possible to understand, in more detail, the exposure scenario. In addition allows also the most suitable risk management measures identification. This approach can be also used when there is a need of identifying the workplace surfaces for sampling chemicals that have the dermal exposure route as the most important. In this case is possible to identify, through detail observation of tasks performance, the surfaces that involves higher contact (frequency) by the workers and can be contaminated. Identify the surfaces to sample when performing occupational exposure assessment to antineoplasic agents. Surfaces selection done based on the task-based approach.

Cyto- and Genotoxicity assessment of manufactured nano cerium dioxide in the A549 cell line

In the past decades the growing application of nanomaterials (NMs) in diverse consumer products has raised various concerns in the field of toxicology. They have been extensively used in a broad range of applications and cover most of the industrial sectors as well as the medicine and the environmental areas. The most common scenarios for human exposure to NMs are occupational, environmental and as consumers and inhalation is the most frequent route of exposure, especially in occupational settings. Cerium dioxide NMs (nano-CeO2) are widely used in a number of applications such as in cosmetics, outdoor paints, wood care products as well as fuel catalysts. For such reason, nano-CeO2 is one of the selected NMs for priority testing within the sponsorship program of the Working Party of Manufactured Nanomaterials of the OECD. In this context, the aim of this study is to assess the safety of nano-CeO2 (NM-212, Joint Research Center Repository) through the characterization of its cytotoxicity and genotoxicity in a human alveolar epithelial cell line. A dispersion of the NM in water plus 0.05% BSA was prepared and sonicated during 16 minutes, according to a standardized protocol. DLS analysis was used to characterize the quality of the NM dispersion in the culture medium. To evaluate the cytotoxicity of nano-CeO2 in the A549 cell line, the colorimetric MTT assay was performed; the capacity of cells to proliferate when exposed to CeO2 was also assessed with the Clonogenic assay. The genotoxicity of this NM was evaluated by the Comet Assay (3 and 24h of exposure) to quantify DNA breaks and the FPG-modified comet assay to assess oxidative DNA damage. The Cytokinesis-Block Micronucleus (CBMN) assay was used to further detect chromosome breaks or loss. The nano-CeO2 particles are spherical, displaying a diameter of 33 nm and 28 m2/g of surface area. The results of the MTT assay did not show any decreased in cells viability following treatment with a dose-range of nano-CeO2 during 24h. Nevertheless, the highest concentrations of this NM were able to significantly reduce the colony forming ability of A549 cells, suggesting that a prolonged exposure may be cytotoxic to these cells. Data from both genotoxicity assays revealed that nano-CeO2 was neither able to induce DNA breaks nor oxidative DNA damage. Likewise, no significant micronucleus induction was observed. Taken together, the present results indicate that this nano-CeO2 is not genotoxic in this alveolar cell line under the tested conditions, although further studies should be performed, e.g., gene mutation in somatic cells and in vivo chromosome damage (rodent micronucleus assay) to ensure its safety to human health.

Polycyclic aromatic hydrocarbons at fire stations: firefighters’ exposure monitoring and biomonitoring, and assessment of the contribution to total internal dose

This work characterizes levels of eighteen polycyclic aromatic hydrocarbons (PAHs) in the breathing air zone of firefighters during their regular work shift at eight Portuguese fire stations, and the firefighters' total internal dose by six urinary monohydroxyl metabolites (OH-PAHs). Total PAHs (ΣPAHs) concentrations varied widely (46.4-428ng/m(3)), mainly due to site specificity (urban/rural) and characteristics (age and layout) of buildings. Airborne PAHs with 2-3 rings were the most abundant (63.9-95.7% ΣPAHs). Similarly, urinary 1-hydroxynaphthalene and 1-hydroxyacenaphthene were the predominant metabolites (66-96% ΣOH-PAHs). Naphthalene contributed the most to carcinogenic ΣPAHs (39.4-78.1%) in majority of firehouses; benzo[a]pyrene, the marker of carcinogenic PAHs, accounted with 1.5-10%. Statistically positive significant correlations (r≥0.733, p≤0.025) were observed between ΣPAHs and urinary ΣOH-PAHs for firefighters of four fire stations suggesting that, at these sites, indoor air was their major exposure source of PAHs. Firefighter's personal exposure to PAHs at Portuguese fire stations were well below the existent occupational exposure limits. Also, the quantified concentrations of post-shift urinary 1-hydroxypyrene in all firefighters were clearly lower than the benchmark level (0.5μmol/mol) recommended by the American Conference of Governmental Industrial Hygienists.

French good practice guidelines for medical and occupational surveillance of the low back pain risk among workers exposed to manual handling of loads

International audience

A comparison of neck bending and flexion measurement methods for assessment of ergonomic risk

International audience

French good practice guidelines for management of the risk of low back pain among workers exposed to manual material handling: Hierarchical strategy of risk assessment of work situations

International audience

Management of safety climate and the psychosocial work environment – new challenges for occupational health and safety professionals?

Introduction: The work environment and Occupational Health and Safety (OHS) practice have changed over the last number of years. A holistic OHS approach has been recommended by the authorities in this field (e.g. World Health Organisation (WHO), European Agency for Safety and Health at Work (EU-OSHA) and the International Labour Organisation (ILO)). This involves a unified action engaging elements of the physical and psychosocial workplace with greater focus on prevention and promotion of health and wellbeing. The health and safety practitioner (HSP) has been recognised as one of the main agents for implementation of OHS. Within an organisation they act as a leader of change and a professional who shapes health and safety while safeguarding the wellbeing of individuals at work. Additionally, safety climate (SC) has been developed as an essential concept for OHS of an organisation, its productivity and the wellbeing of its workforce. Scholars and practitioners have recognised the great need for further empirical evidence on the HSP’s role in a changing work environment that increasingly requires the use of preventative measures and the assessment and management of psychosocial work-related risks. This doctoral research brings together the different concepts used in OHS and Public Health including SC, Psychosocial workplace risks, Health Promotion and OHS performance. The associations between these concepts are analysed bearing in mind the WHO Healthy Workplace Framework and three of its main components (physical and psychosocial work environment and health resources). This thesis aims to establish a deeper understanding of the practice and management of OHS in Ireland and the UK, exploring the role of HSPs (employed in diverse sectors of activity) and of SC in the OHS of organisations. Methods: One systematic review and three cross-sectional research studies were performed. The systematic review focussed on the evidence compiled for the association of SC with accidents and injuries at work, clarifying this concept’s definition and its most relevant dimensions. The second article (chapter 3) explored the association of SC with accidents and injuries in a sample of workers (n=367) from a pharmaceutical industry and compared permanent with non-permanent workers. Associations of safety climate with employment status and with self-reported occupational accidents/injuries were studied through logistic regression modelling. The third and fourth papers in this thesis investigated the main tasks performed by HSPs, their perceptions of SC, health climate (HC), psychosocial risk factors and health outcomes as well as work efficacy. Validated questionnaires were applied to a sample of HSPs in Ireland and UK, members of the Institute of Occupational Safety and Health (n=1444). Chi-square analysis and logistic regression were used to assess the association between HSPs work characteristics and their involvement in the management of Psychosocial Risk Factors, Safety Culture and Health Promotion (paper 3). Multiple linear regression analysis was used to determine the association between SC, HC, psychosocial risk factors and health outcomes (general health and mental wellbeing) and self-efficacy. Results: As shown in the systematic review, scientific evidence is unable to establish the widely assumed causal link between SC and accidents and injuries. Nevertheless, the current results suggested that, particularly, the organisational dimensions of SC were associated with accidents and injuries and that SC is linked to health, wellbeing and safety performance in the organisation. According to the present research, contingent workers had lower SC perceptions but showed a lower accident/injury rate than their permanent colleagues. The associations of safety climate with accidents/injuries had opposite directions for the two types of workers as for permanent employees it showed an inverse relationship while for temporary workers, although not significant, a positive association was found. This thesis’ findings showed that HSPs are, to a very small degree, included in activities related to psychosocial risk management and assessment, to a moderate degree, involved in HP activities and, to a large degree, engaged in the management of safety culture in organisations. In the final research study, SC and HC were linked to job demands-control-support (JDCS), health, wellbeing and efficacy. JDCS were also associated with all three outcomes under study. Results also showed the contribution of psychosocial risk factors to the association of SC and HC with all the studied outcomes. These associations had rarely been recorded previously. Discussion & Conclusions: Health and safety climate showed a significant association with health, wellbeing and efficacy - a relationship which affects working conditions and the health and wellbeing of the workforce. This demonstrates the link of both SC and HC with the OHS and the general strength or viability of organisations. A division was noticed between the area of “health” and “safety” in the workplace and in the approach to the physical and psychosocial work environment. These findings highlighted the current challenge in ensuring a holistic and multidisciplinary approach for prevention of hazards and for an integrated OHS management. HSPs have shown to be a pivotal agent in the shaping and development of OHS in organisations. However, as observed in this thesis, the role of these professionals is still far from the recommended involvement in the management of psychosocial risk factors and could have a more complete engagement in other areas of OHS such as health promotion. Additionally, a strong culture of health and safety with supportive management and buy-in from all stakeholders is essential to achieve the ideal unified and prevention-focussed approach to OHS as recommended by the WHO, EU-OSHA and ILO.

An Assessment to Toxicological Risk of Pesticide Exposure

On the one hand, pesticides may be absorbed into the body orally, dermally, ocularly and by inhalation and the human exposure may be dietary, recreational and/or occupational where toxicity could be acute or chronic. On the other hand, the environmental fate and toxicity of the pesticide is contingent on the physico-chemical characteristics of pesticide, the soil composition and adsorption. Human toxicity is also dependent on the exposure time and individual’s susceptibility. Therefore, this work will focus on the development of an Artificial Intelligence based diagnosis support system to assess the pesticide toxicological risk to humanoid, built under a formal framework based on Logic Programming to knowledge representation and reasoning, complemented with an approach to computing grounded on Artificial Neural Networks. The proposed solution is unique in itself, once it caters for the explicit treatment of incomplete, unknown, or even self-contradictory information, either in terms of a qualitative or quantitative setting.

Assessment Of The Fixation Of Mandibular Symphysis Fractures Using Conical Cannulated Screws: Mechanical And Photoelastic Tests.

The aim of this study was to use mechanical and photoelastic tests to compare the performance of cannulated screws with other fixation methods in mandibular symphysis fractures. Ten polyurethane mandibles were allocated to each group and fixed as follows: group PRP, 2 perpendicular miniplates; group PLL, 1 miniplate and 1 plate, parallel; and group CS, 2 cannulated screws. Vertical linear loading tests were performed. The differences between mean values were analyzed with the Tukey test. The photoelastic test was carried out using a polariscope. The results revealed differences between the CS and PRP groups at 1, 3, 5, and 10 millimeters of displacement. The photoelastic test confirmed higher stress concentration in all groups close to the mandibular base, whereas the CS group showed it throughout the region assessed. Conical cannulated screws performed well in mechanical and photoelastic tests.

[health Protection For Rural Workers: The Need To Standardize Techniques For Quantifying Dermal Exposure To Pesticides].

Quantification of dermal exposure to pesticides in rural workers, used in risk assessment, can be performed with different techniques such as patches or whole body evaluation. However, the wide variety of methods can jeopardize the process by producing disparate results, depending on the principles in sample collection. A critical review was thus performed on the main techniques for quantifying dermal exposure, calling attention to this issue and the need to establish a single methodology for quantification of dermal exposure in rural workers. Such harmonization of different techniques should help achieve safer and healthier working conditions. Techniques that can provide reliable exposure data are an essential first step towards avoiding harm to workers' health.

Cardiac Magnetic Resonance Assessment Of Interstitial Myocardial Fibrosis And Cardiomyocyte Hypertrophy In Hypertensive Mice Treated With Spironolactone.

Nearly 50% of patients with heart failure (HF) have preserved LV ejection fraction, with interstitial fibrosis and cardiomyocyte hypertrophy as early manifestations of pressure overload. However, methods to assess both tissue characteristics dynamically and noninvasively with therapy are lacking. We measured the effects of mineralocorticoid receptor blockade on tissue phenotypes in LV pressure overload using cardiac magnetic resonance (CMR). Mice were randomized to l-nitro-ω-methyl ester (l-NAME, 3 mg/mL in water; n=22), or l-NAME with spironolactone (50 mg/kg/day in subcutaneous pellets; n=21). Myocardial extracellular volume (ECV; marker of diffuse interstitial fibrosis) and the intracellular lifetime of water (τic; marker of cardiomyocyte hypertrophy) were determined by CMR T1 imaging at baseline and after 7 weeks of therapy alongside histological assessments. Administration of l-NAME induced hypertensive heart disease in mice, with increases in mean arterial pressure, LV mass, ECV, and τic compared with placebo-treated controls, while LV ejection fraction was preserved (>50%). In comparison, animals receiving both spironolactone and l-NAME (l-NAME+S) showed less concentric remodeling, and a lower myocardial ECV and τic, indicating decreased interstitial fibrosis and cardiomyocyte hypertrophy (ECV: 0.43 ± 0.09 for l-NAME versus 0.25 ± 0.03 for l-NAME+S, P<0.001; τic: 0.42 ± 0.11 for l-NAME groups versus 0.12 ± 0.05 for l-NAME+S group). Mice treated with a combination of l-NAME and spironolactone were similar to placebo-treated controls at 7 weeks. Spironolactone attenuates interstitial fibrosis and cardiomyocyte hypertrophy in hypertensive heart disease. CMR can phenotype myocardial tissue remodeling in pressure-overload, furthering our understanding of HF progression.

The Inadequacy Of The Y-axis Of Growth (sngn) For The Vertical Pattern Assessment In Patients With Sagittal Discrepancies.

The aim of this cephalometric study was to evaluate the influence of the sagittal skeletal pattern on the 'Y-axis of growth' measurement in patients with different malocclusions. Lateral head films from 59 patients (mean age 16y 7m, ranging from 11 to 25 years) were selected after a subjective analysis of 1630 cases. Sample was grouped as follows: Group 1 - class I facial pattern; group 2 - class II facial pattern; and Group 3 - class III facial pattern. Two angular measurements, SNGoGn and SNGn, were taken in order to determine skeletal vertical facial pattern. A logistic regression with errors distributed according to a binomial distribution was used to test the influence of the sagittal relationship (Class I, II, III facial patterns) on vertical diagnostic measurement congruence (SNGoGn and SNGn). RESULTS show that the probability of congruence between the patterns SNGn and SNGoGn was relatively high (70%) for group 1, but for groups II (46%) and III (37%) this congruence was relatively low. The use of SNGn appears to be inappropriate to determine the vertical facial skeletal pattern of patients, due to Gn point shifting throughout sagittal discrepancies. Clinical Significance: Facial pattern determined by SNGn must be considered carefully, especially when severe sagittal discrepancies are present.

Assessment Of Robustness On Analysis Using Headspace Solid-phase Microextraction And Comprehensive Two-dimensional Gas Chromatography Through Experimental Designs.

Plackett-Burman experimental design was applied for the robustness assessment of GC×GC-qMS (Comprehensive Two-Dimensional Gas Chromatography with Fast Quadrupolar Mass Spectrometric Detection) in quantitative and qualitative analysis of volatiles compounds from chocolate samples isolated by headspace solid-phase microextraction (HS-SPME). The influence of small changes around the nominal level of six factors deemed as important on peak areas (carrier gas flow rate, modulation period, temperature of ionic source, MS photomultiplier power, injector temperature and interface temperature) and of four factors considered as potentially influential on spectral quality (minimum and maximum limits of the scanned mass ranges, ions source temperature and photomultiplier power). The analytes selected for the study were 2,3,5-trimethylpyrazine, 2-octanone, octanal, 2-pentyl-furan, 2,3,5,6-tetramethylpyrazine, and 2-nonanone e nonanal. The factors pointed out as important on the robustness of the system were photomultiplier power for quantitative analysis and lower limit of mass scanning range for qualitative analysis.