Publications by authors named "Rolf Merget"
Article Synopsis
- Hypersensitivity pneumonitis (HP) is an uncommon lung allergy primarily caused by inhaling organic dusts, with rare instances linked to chemicals like phthalates found in plastics.
- A clinical case involving a cable production worker demonstrated that symptoms initially diagnosed as idiopathic pulmonary fibrosis were linked to chronic HP resulting from exposure to phthalates, confirmed by specific IgG antibodies and other clinical findings.
- The study highlights the need for greater awareness of phthalates as potential triggers for occupational HP, as it has not been commonly recognized in previous case reports.
Article Synopsis
- Zinc fever is typically known to affect workers handling zinc at high temperatures, but its occurrence at low temperatures was previously unclear.
- A 33-year-old painter experienced respiratory issues and fever related to zinc coatings used at room temperature, leading to a diagnosis of zinc fever after ruling out other conditions.
- This case highlights that zinc-containing materials, even when applied at lower temperatures, can pose significant health risks to workers in occupations such as painting and varnishing.
Exposure to airborne substances such as gases, vapours, and particles remains a relevant health risk in many workplaces. A current topic and cause for discussion is the investigation of the health effects of particles containing zinc oxide (ZnO). Among other data, those collected from our study on human exposure data of ZnO in 2018 prompted the National Research Centre for the Working Environment 2021 to formulate a new, sharply lowered proposed occupational exposure limit (OEL) for zinc in workplaces.
View Article and Find Full Text PDFOccupational exposure to microbially contaminated metal working fluids (MWF) can cause hypersensitivity pneumonitis (HP). An important step in the diagnosis of HP is to identify the triggering antigen by detection of corresponding specific IgG antibodies (sIgG). As commercial sIgG tests are currently not available, protein antigens were prepared from MWF-workplace samples and from MWF-typical bacterial isolates.
View Article and Find Full Text PDFBackground: Most threshold limit values are based on animal experiments. Often, the question remains whether these data reflect the situation in humans. As part of a series of investigations in our exposure lab, this study investigates whether the results on the inflammatory effects of particles that have been demonstrated in animal models can be confirmed in acute inhalation studies in humans.
View Article and Find Full Text PDFArticle Synopsis
- - The study examined the relationship between mold exposure, allergic reactions (IgE sensitization), inflammation, and respiratory issues in 46 mold-exposed individuals and 23 non-exposed individuals, using questionnaires for assessment.
- - Results showed that 41% of those exposed had elevated specific IgE levels to a mold mixture compared to 17% in non-exposed individuals; exposed asthmatics showed the highest sensitization at 55%.
- - A notable finding was lower levels of a protein (CC16) in the serum of exposed subjects, particularly asthmatics, indicating that specific IgE to molds is a significant marker for diagnosing mold-related respiratory symptoms.
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View Article and Find Full Text PDFA 58-year-old non-atopic chemical worker complained about work-related asthma and rhinoconjunctivitis about 4 years after exposure to quillaja bark and soapnut. Bronchial hyperresponsiveness was demonstrated after withdrawal of medication for 12 hours. Skin prick tests with extracts from quillaja bark and soapnut from the workplace were positive, but ImmunoCAP was positive only with quillaja bark, probably due to the low protein content of the extract from soapnut.
View Article and Find Full Text PDFA 37-year-old butcher developed respiratory symptoms during sausage and chicken production in a large company. In addition to various spices, the enzyme transglutaminase was a possible cause. The lung function test showed mild partial reversible airway obstruction and severe bronchial hyperresponsiveness.
View Article and Find Full Text PDFDiisocyanates continue to be one of the most frequent causes of occupational asthma worldwide. They are still indispensable in industrial use as components of coatings, glues, and polyurethane foams. In Germany, respiratory diseases due to diisocyanates can be compensated by the statutory accident insurance (according to BK-Nr.
View Article and Find Full Text PDFInhalation of ZnO particles can cause inflammation of the airways and metal fume fever. It is unclear if different sizes of the particles alter these effects. However, various studies report higher biological activity of other nano-sized particles compared to microparticles.
View Article and Find Full Text PDFBackground: Exposure to airborne zinc oxide (ZnO) particles occurs in many industrial processes, especially in galvanizing and welding. Systemic inflammation after experimental inhalation of ZnO particles has been demonstrated previously, but little is known about the impact on the cardiovascular system, particularly on the autonomic cardiac system and the risk of arrhythmias. In this study we investigated the short-term effects of ZnO nanoparticles on heart rate variability (HRV) and repolarization in healthy adults in a concentration-dependent manner at rest and during exercise in a controlled experimental set-up.
View Article and Find Full Text PDFArticle Synopsis
- Inhalation of high concentrations of zinc oxide (ZnO) particles can lead to metal fume fever, and a method to assess immune responses is the whole blood assay (WBA), which measures cytokine release.
- This study aimed to see how inhaling nano-sized ZnO particles affects WBA results in healthy individuals, with subjects exposed to different concentrations of ZnO over several days.
- While the overall response was not significantly influenced by ZnO exposure, the findings indicated that even low doses (0.5 mg/m) caused notable changes in immune markers, but these cytokine levels should not be interpreted as indicators of disease.
Background: Workers in the zinc production and processing of galvanized sheet steel are exposed to a complex mixture of particles and gases, including zinc oxide (ZnO) that can affect human health. We aimed to study the effects of short-term controlled exposure to nano-sized ZnO on airway inflammatory markers in healthy volunteers.
Methods: Sixteen subjects (8 females, 8 men; age 19-42, non-smokers) were exposed to filtered air and ZnO nanoparticles (0.
Phenotyping Occupational Asthma Caused by Acrylates in a Multicenter Cohort Study.
J Allergy Clin Immunol Pract
March 2020
Background: While acrylates are well-known skin sensitizers, they are not classified as respiratory sensitizers although several cases of acrylate-induced occupational asthma (OA) have been reported.
Objective: To evaluate the characteristics of acrylate-induced OA in a large series of cases and compare those with OA induced by other low-molecular-weight (LMW) agents.
Methods: Jobs and exposures, clinical and functional characteristics, and markers of airway inflammation were analyzed in an international, multicenter, retrospective cohort of subjects with OA ascertained by a positive inhalation challenge to acrylates (n = 55) or other LMW agents (n = 418) including isocyanates (n = 125).
Background: Fractional exhaled nitric oxide (FeNO) before and after specific inhalation challenge has been postulated as an additional tool in the diagnosis of occupational asthma (OA), but little is known about serial FeNO measurements at home and at work. The aim of the present study was to assess the contribution of serial measurements of FeNO off and at work toward the diagnosis of OA.
Methods: Forty-one subjects with suspected (n = 35) or diagnosed (n = 6) OA performed FeNO measurements once daily during a 2-week holiday and a subsequent 2-week work period.
Purpose: Increases of fractional exhaled nitric oxide (FeNO), sputum eosinophils, and methacholine responsiveness have been described after specific inhalation challenges (SIC) with occupational allergens, but limited information is available about their comparative performance. It was the aim of the study to assess the diagnostic accuracy of these non-invasive tests before and after SIC for the diagnosis of occupational asthma (OA).
Methods: A total of 122 subjects with work-related shortness of breath were included.
Severe Occupational Asthma: Insights From a Multicenter European Cohort.
J Allergy Clin Immunol Pract
October 2020
Background: Although sensitizer-induced occupational asthma (OA) accounts for an appreciable fraction of adult asthma, the severity of OA has received little attention.
Objective: The aim of this study was to characterize the burden and determinants of severe OA in a large multicenter cohort of subjects with OA.
Methods: This retrospective study included 997 subjects with OA ascertained by a positive specific inhalation challenge completed in 20 tertiary centers in 11 European countries during the period 2006 to 2015.
Background: High-molecular-weight (HMW) proteins and low-molecular-weight (LMW) chemicals can cause occupational asthma (OA) although few studies have thoroughly compared the clinical, physiological, and inflammatory patterns associated with these different types of agents. The aim of this study was to determine whether OA induced by HMW and LMW agents shows distinct phenotypic profiles.
Methods: Clinical and functional characteristics, and markers of airway inflammation were analyzed in an international, multicenter, retrospective cohort of subjects with OA ascertained by a positive inhalation challenge response to HMW (n = 544) and LMW (n = 635) agents.
Article Synopsis
- * Blood samples from 16 healthy volunteers were collected across 6 days, with cytokine levels (IL-1β and IL-8) quantified after a 22-hour stimulation with varying endotoxin concentrations.
- * Results showed a consistent dose-response relationship and highlighted significant variability in cytokine responses among individuals, suggesting the need for personalized assessment of immune response variability.
Purpose: An increase of fractional exhaled nitric oxide (FeNO) has been described after specific inhalation challenges (SICs) with occupational allergens, but the clinical role of FeNO measurements before and after SIC is unknown. It was the aim of this study to assess the diagnostic accuracy of FeNO measurements before and after SIC in subjects with suspected occupational asthma (OA).
Methods: One hundred forty-eight patients with suspected OA were examined by SIC with various occupational allergens.