Respirable Dust Levels Research Articles

Neurological and neurobehavioral effects of welders in Egypt exposed to manganese containing welding fumes.

Welders are more likely to develop neurobehavioral disorders because of their exposure to neurotoxic metals such as manganese. This study aimed to measure the neurobehavioral performance of welders occupationally exposed to manganese at welding enterprises and its relationship with the workplace environment. It is a comparative cross-sectional study carried out on 130 welders working at 50 welding enterprises in Menoufia governorate, Egypt, compared to 130 non-occupationally exposed controls. It was found that the environments of the studied welding enterprises had levels of respirable dust, manganese, and total welding fumes that exceeded internationally permissible limits. In addition, the mean blood manganese levels were significantly higher among welders (4.16 ± 0.61) than the controls (1.72 ± 0.41). Welders had a significantly higher prevalence of neurological manifestations and lower performance of neurobehavioral tests. Lower neurobehavioral performance among welders was significantly correlated with increased work duration and blood levels in some tests. To lessen the fumes in the breathing zone of workers, it is therefore strongly recommended to regularly wear high-quality personal protective equipment, especially masks, and to ensure proper ventilation.

94 Reducing Exposure to Respirable Crystalline Silica in the Construction and Minerals Industry by Using Wearable Real Time Respirable Dust Monitors

Abstract Real time monitoring of respirable dust (as a surrogate for RCS) opens the opportunity to warn workers when entering work areas with increased dust levels to provide them the information to fit RPE properly or exit the area. However in the past, the adoption of such monitoring approaches has been limited due to the bulkiness and price of devices. This paper reflects on how the miniaturisation of Optical Particle Counters has enabled light weight (<150g) wearable devices to be developed which are convenient for workers in the construction and minerals industry to wear on all working days. It provides an overview of the Optical particle counter. its performance in measuring respirable dust and how it has been integrated into a battery powered ' DustCanary; wearable device. Due to its size and convenience the DustCanary provides protection to both those at first line risk due to the areas they work (eg stone cutters, plant operatives) who by wearing such can devices can help identify changes in performance of Local Exhaust Ventilation (LEV). or controls so that remedial action can be taken secondary risk on a plant who are not necessarily wearing RPE (such as delivery drivers) who can be warned when they enter an area where there are elevated respirable dust levels Case study data and examples will be shared.

Mineralogical Study of Respirable Dust in Artisanal SmallScale Quarries of Misisi Compound, Lusaka, Zambia

Misisi compound in Lusaka is characterized by artisanal small scale quarrying activities which are often dusty in nature and prone to hazards. This study reports respirable dust concentration and the mineralogical composition of rocks in the workplace. Dust sampling was carried out with the help of gravimetric samplers at five quarries. Respirable dust samples were collected during digging, chiselling, crushing, and loading sites. The results of the sampled dust indicated high levels of respirable dust at all five quarry crushing sites. For example, based on Time Weighted Average (TWA), the respirable dust concentration at the crushing site was recorded as 12.75 mg/m3 at quarry#1 compared to the Maximum Allowable Concentration (MAC) of 5 mg/m3 of Occupational Safety and Health Administration (OSHA). The results of mineralogical testing and analyses revealed that marble was the common rock type that was being mined by most of the ASMs in the studied area. Based on the point count data analysis, marble contained 98% CaCO3 and 2% SiO2.

Exposure to respirable dust and factors associated with abnormal pulmonary function among stone diggers in Kayole quarries, Nairobi City County, Kenya

Background: In Kenya, the quarry industry suffers several constraints: some quarry workers get injured, others get chronic diseases, while some die. This study assessed occupational exposure to respirable dust and factors associated with abnormal pulmonary function among quarry stone diggers in Mihang’o and Matopeni quarries in Kayole Nairobi City County, Kenya. Methods: The study was done in Mihang’o and Matopeni quarries. An analytical cross-sectional design was used and a sample size of 165 respondents was taken. An interviewer administered semi structured questionnaire. Spirometry tests were done by a qualified technician to assess pulmonary function. Respirable dust levels were determined with the aid of a particle counter. Descriptive statistics like frequency, means were used to summarize data and results were presented in frequency tables and graphs. Chi square tests and logistic regression were done. T tests were done to compare the means of dust levels in the two quarries. Results: This study found the daily mean levels of PM2.5 and PM10 were higher than the levels recommended by WHO. The age of the respondents, presence of respiratory symptoms, years of work experience, nostril covering, and smoking were factors associated with abnormal pulmonary function at (p≤0.05). Conclusions: In conclusion, chronic exposure to quarry dust increases the risk of developing respiratory symptoms and abnormal pulmonary function. This study recommended that routine particulate matter monitoring should be done in Nairobi quarries to provide data that can inform decisions on air pollution control actions.

Influence of Shift Work on Arterial Stiffness and Systemic Inflammation: A 3-Year Follow-up Study in Industry.

To assess changes in cardiovascular disease risk factors during a 3-year follow-up among 57 rotating shift workers and 29 day workers in industry. We collected demographics by questionnaire, examined blood pressure, heart rate, pulse wave velocity, carotid media thickness, and maximal oxygen uptake. We assessed blood samples for determination of lipids, glycosylated hemoglobin, C-reactive protein, markers of inflammation, and particle concentrations/respirable dust. Baseline comparisons were analyzed using logistic regression (plaque) and linear regression for all other outcomes. We applied mixed models to assess differences in change in health outcomes between the shift workers and the day workers. At baseline, the adhesion molecules soluble vascular cell adhesion molecule 1 and soluble P-selectin were elevated among the shift workers compared with that of the day workers. There was a significant difference in change in pulse wave velocity between shift workers (1.29-m/s increase) and day workers (0.11-m/s increase) over the 3-year follow-up. Respirable dust levels were below the Norwegian occupational exposure limit. Shift work in industry is associated with arterial stiffening reflecting increased risk for future cardiovascular disease. More uncertainly, we found some support for systemic inflammation.

Metal Exposure-Related Welder's Pneumoconiosis and Lung Function: A Cross-Sectional Study in a Container Factory of China.

Long-term inhalation of welding fume at high exposure can cause welder's pneumoconiosis, and metals in welding dust are associated with respiratory dysfunction. This cross-sectional study, which contains 384 Chinese male workers who were or had been working in a container factory, aimed to assess the potential risk of haemal and urinary metal content in welder's pneumoconiosis. Further, we investigated their effects on lung function parameters. Metal content and lung function were measured using inductively coupled plasma-mass spectrometry (ICP-MS) and spirometer, respectively. The concentration and metal content of respirable dust as well as total dust were collected at this container factory. Lung function of cases with welder's pneumoconiosis was significantly worse, as indicated by lower values of FVC, FVC% predicted, FEV1, FEV1% predicted, MEF25% predicted, and MMEF% predicted (p < 0.05). Results of logistic regression models showed that haemal Cr and Zn were risk factors of welder's pneumoconiosis (OR = 4.98, 95%CI: 1.73-21.20, p = 0.009 for Cr; OR = 5.23, 95%CI: 1.56-41.08, p = 0.033 for Zn) after adjusted with age, BMI, working years, welding dust exposure years, and smoking status. Multiple linear regression models showed that several metals (haemal Cd and Pb; urinary Cd and Fe) were significantly associated with different lung function indices in the welder's pneumoconiosis group. Compared to non-welders, welders were exposed to considerably higher levels of respirable dust, total dust, and six kinds of metals (p < 0.05). In conclusion, haemal Cr and Zn are positively related to welder's pneumoconiosis. Meanwhile, Cd and Pb might worsen lung function in welder's pneumoconiosis.

Benefits and limitations of field-based monitoring approaches for respirable dust and crystalline silica applied in a sandstone quarry

With the advent of new sensing technologies and robust field-deployable analyzers, monitoring approaches can now generate valuable hazard information directly in the workplace. This is the case for monitoring respirable dust and respirable crystalline silica concentration levels. Estimating the quartz amount of a respirable dust sample by nondestructive analysis can be carried out using portable Fourier transform infrared spectroscopy (FTIR) units. Real-time respirable dust monitors, combined with small video cameras, allow advanced assessments using the Helmet-CAM methodology. These two field-based monitoring approaches, developed by the National Institute for Occupational Safety and Health (NIOSH), have been trialed in a sandstone quarry. Twenty-six Helmet-CAM sessions were conducted, and forty-one dust samples were collected around the quarry and analyzed on-site during two events. The generated data generated were used to characterize concentration levels for the monitored areas and workers, to identify good practices, and to illustrate activities that could be improved with additional engineered control technologies. Laboratory analysis of the collected samples complemented the field finding and provided an assessment of the performance of the field-based techniques. Only a fraction of the real-time respirable dust monitoring sessions data could be corrected with laboratory analysis. The average correction factor ratio was 5.0. Nevertheless, Helmet-CAM results provided valuable information for each session. The field-based quartz monitoring approach overestimated the concentration by a factor of 1.8, but it successfully assessed the quartz concentration trends in the quarry. The data collected could be used for the determination of a quarry calibration factor for future events. The quartz content in the dust was found to vary from 14% to 100%, and this indicates the need for multiple techniques in the characterization of respirable dust and quartz concentration and exposure. Overall, this study reports the importance of the adoption of field-based monitoring techniques when combined with a proper understanding and knowledge of the capabilities and limitations of each technique.

Why are Silica Dust Exposures and Silica-Related Health Effects Still a Global Concern?

Background and aim Epidemiology studies of workers exposed to silica dust demonstrate that crystalline SiO2 is a multipotential hazard. Research among construction workers, miners, ceramic and brick workers, countertops workers, and sandblasters where respirable silica dust levels has been measured has demonstrated excess risk for silicosis, cor pulmopale, silica-tuberculosis (SiTB), several chronic respiratory conditions, coal workers pneumoconiosis (CWP), several auto-immune diseases, and cancers of the lung and gastro-intestinal tract. Methods Despite knowledge of these links over the past decades, occupational and environmental health professionals have not been able to address three new silica-related health issues. They are silicosis and CWP among US coal miners, severe silicosis and auto-immune ailments among countertop workers; and ongoing risk for SiTB among Africa miners. The author examined the literature for other novel silica-related health risks. Results Current workers and their managers seem to not have sufficient awareness of the occupational hazards of silica dust. There are new silica dust concerns including fracking sand, railroad ballast, and dust control in countertop machining. There are new cancer links with silica, including women and nonsmokers with excess lung cancer; excess lung cancer among patients with CWP; children’s dust exposure in small-scale gold mining; and excess lung diseases and pulmonary cancer among railroad workers. There is need for research on improved silica sampling techniques and protective gear. Pathologists should explore whether silicosis leads to differences in cell characteristics that produce silica-linked lung cancers compared to ‘garden variety’ malignancies. Conclusion Despite promises that global silica problems were controlled, that seems to be countered by excesses of CWP and SiTB that still bedevil the occupational medicine and public health communities. We need more worker education, prevention or regulatory policy, and basic silica biology and pathology to effectively intervene. Keywords Silica health effects, future prevention efforts; improved sampling methods

Descriptive Study of Respirable Dust Levels By Furniture Industry Workers in Nanggalo District, Padang City in 2020

Rapid development, especially in the field of industry and technology, causes changes in the composition of the air beyond the carrying capacity of the environment, this has a negative impact on humans, namely air pollution and pollution that can affect the degree of human health, especially the furniture industry in Padang City, precisely in Nanggalo District. This study aims to determine the levels of inhaled dust (Respirable) by workers in the furniture industry in Nanggalo District. The design of this research is descriptive, which describes the levels of inhaled dust (Respirable) by furniture industry workers in Nangalo District, Padang City in 2020. The population in this study was 48 workers, a sample of 21 workers was taken based on the number of workers in the furniture industry who worked in the production section. The data obtained were analyzed univariately. The results of the study using the Personal Dust Sampler tool used for each worker showed that the levels of inhaled dust (Resprable) by 15 furniture industry workers in Nanggalo District were found to meet the requirements, namely < 3 mg/m3 and 6 workers did not meet the requirements, namely > 3 mg/m3. It can be concluded that the levels of dust inhaled by furniture industry workers in Nanggalo District are those who meet the requirements and some do not. It is recommended for companies or the management of the furniture industry in Nanggalo District, namely providing and supervising the use of personal protective equipment (PPE) for workers, and the need for renovation of production sites, especially the provision of insulation and arrangement of safe and comfortable work spaces between workers.

Occupational exposure to particles and biomarkers of cardiovascular disease—during work and after vacation

ObjectiveAmbient particle matter is a risk factor for cardiovascular disease (CVD). However, little is known about associations between particles in occupational settings and risk of CVD. We investigated associations between occupational dust exposure and biomarkers of CVD, and potential recovery effects after vacation.MethodsPersonal dust exposure measurements (respirable silica, respirable dust < 4 µm, and particles of 0.1–10 µm (PM 0.1–10) were conducted once, and biological sampling were performed twice on non-smoking, male construction workers in Stockholm county, Sweden; during work and immediately after summer vacation. Linear regressions with adjustments for confounders and covariates were performed evaluating associations between occupational dust exposure and biomarkers. Paired t tests were performed evaluating changes before and after vacation.ResultsSixty-five workers participated. Homocysteine concentrations were significantly higher with increasing concentrations (mg/m3) of respirable silica, respirable dust, and PM 0.1–10, and pulse rate with higher levels of respirable dust and dust of PM 0.1–10. Homocysteine levels were also positively correlated to number of years of dust exposure, as were low-density lipoprotein (LDL) levels. A clear recovery effect was present for LDL after vacation, but not for homocysteine.ConclusionsOccupational dust exposure was associated with some CVD risk markers, even at mean exposure concentrations below the Swedish occupational exposure limits for respirable silica and respirable dust, respectively. Vacation resulted in recovery for some risk markers. However, the change of the homocysteine and LDL levels suggest a long-term effect. Reduction of occupational exposure to dust may decrease the risk of CVD among exposed workers.

Analysis of Increasing Case of Acute Respiratory Infections (ARI) in Nickel Mining Environment in Pomalaa District, Kolaka Regency, Southeast Sulawesi

Introduction: The mining process that has been carried out for a long time in large quantities often ignores environmental sustainability which in the end can result in various negative impacts that are felt in the short and long term. The purpose of the study was to determine the level of air pollution by Nickel dust and to analyze the relationship between exposure to Nickel dust and ARI disease in people living around the Nickel mining industry in Pomalaa District.&#x0D; Method: This study uses a cross-sectional design using a non-interventional type of research conducted in residential areas around the mining area of ​​PT Aneka Tambang Tbk, Kolaka Regency, Southeast Sulawesi Province as a mining designation area, namely in Pomalaa District.&#x0D; Result: The results showed that the average outdoor air quality for the S02 parameter in the designated area was higher than in the non-designated area, as well as for the N02 parameter, for the H2S parameter in both areas the average value was the same, but for the PM10 value in the designated area is higher than in the non-designated area, while the temperature, humidity, and wind speed in the two areas are almost the same.&#x0D; Conclusion: This is in line with the results of research conducted by Qomariyatus S (in 2007) conducted around the coal mine of PT Aneka Tambang,Southeast Sulawesi showed that the level of respirable dust in the field slightly exceeded the normal threshold value of 2.19 mg/m3.

Respirable Dust Levels, Years of Service, and Pulmonary Physiological Disorders in Marble Home Industry Workers

Highlights: The strength of the relationship between respiratory dust levels and pulmonary function disorders could not be obtained. The weakness level of correlation between years of service and pulmonary function disorders. Abstract: Environmental dust in the workplace exposes the workers as they are breathing. The dust is inhaled into the respiratory tract and causes occupational diseases in the form of pulmonary function disorders. Workers in the marble industry are also prone to dust exposure. This study aimed to analyze the correlation between years of service, respiratory dust levels, and pulmonary function disorders in marble home industry workers in Tulungagung Regency, Indonesia. This study was a descriptive observational study with data from a cross-sectional technique. The population was 18 workers taken as respondents. The independent variables in this study were years of service and the level of respirable dust, while the dependent variable was the pulmonary function disorders experienced by the workers. The data were analyzed using the Correlation Contingency test. There was a close correlation between years of service and pulmonary function disorders by 0.196, indicating that the relationship between those variables was weak. The strength of the relationship between respiratory dust levels and pulmonary function disorders could not be obtained because the constant results met the threshold value. The correlation between years of service and pulmonary function disorders was weak, and the relationship between respiratory dust level and pulmonary function disorders could not be obtained.

Air Pollution Associated with Total Suspended Particulate and Particulate Matter in Cement Grinding Plant in Vietnam

Air pollution associated with suspended particles has become a significant concern in Vietnam recently. The study aimed to (1) investigate dust sources; (2) measure concentration levels of Total Suspended Particulate (TSP), Particulate Matter (PM) fractions; (3) identify silica levels and the correlation with respirable particles at a cement grinding plant in Vietnam. A total of 312 samples (52 TSP, 160 PMs) at 13 processes were measured using the direct-reading dust meter. The silica composition was analyzed in a certified laboratory using the X-ray fluorescence (XRF) technique. SPSS version 26 for Window was used to analyze the data. The operations of the cement grinding plant created multiple dust sources from the jetty to the cement dispatch process. The TSP levels ranged 0.06–38.24 mg m−3, and 40.38% (n = 21) TSP samples exceeded the Permissible Exposure Limit (PEL) for an 8-h working shift. Besides that, there was a wide range and significant concentration levels of PMs in the cement processes. The levels of PMs were PM1 (0.00–0.06 mg m−3), PM2.5 (0.01–0.83 mg m−3), PM4 (0.02–4.59 mg m−3), PM7 (0.03–16.94 mg m−3), and PM10 (0.04–26.85 mg m−3). The highest mean levels of PMs factions were measured at the pre-grinding process. The inefficient operation of the dust collector contributed a significant factor to the dust dispersion in this process. The silica’s mean (SD) composition in respirable dust was 20.4% (0.86) and was not significantly different amongst the processes. There was a significant correlation between the levels of respirable dust and silica exposure in the cement grinding plant (r = 0.99). The improvement of indoor air quality is needed to prevent health effects on cement workers.

Coal mine dust lung disease in miners killed in the Upper Big Branch disaster: a review of lung pathology and contemporary respirable dust levels in underground US coal mines

ObjectivesIn 2010, 29 coal miners died due to an explosion at the Upper Big Branch (UBB) mine in West Virginia, USA. Autopsy examinations of 24 individuals with evaluable lung tissue...

Occupational exposure to crystalline silica in artificial stone processing

Respirable Crystalline Silica (RCS) is a hazardous substance with known effects that can be well correlated with exposure levels that still persist in many traditional sectors, such as construction or stone processing. In the past decade, exposure scenarios for RCS have been found in the sector of artificial stone processing. The aim of this study is to evaluate the levels of RCS in facilities specialized in the production of artificial stone countertops and other accessories for the furnishing of kitchens, bathrooms, and offices after the introduction of some preventive technical measures such as wet processing or local exhaust ventilation systems. The study involved 51 subjects in four facilities. Personal silica exposure assessment was carried out using GS3 cyclones positioned in the breathing zone during the work shift. Quantitative determination of silica was carried out by X-ray diffraction analysis. Respirable dust levels were in the range 0.046–1.154 mg/m3 with RCS levels within the range <0.003-0.098 mg/m3. The highest exposure was found in dry finishing operations. Although there was a remarkable reduction in RCS exposure levels compared to what was observed in the past before the introduction of preventive measures, the data still showed hazardous exposure levels for some of the monitored activities.

Characterization of Airborne Particulates and Worker Exposures in Electro-static Powder Coating Operations.

This study was to examine the airborne particulates/dusts and worker exposures in electro-static powder coating operations. Temporal variation and size distribution of dusts were assessed using direct-reading instrument, while the worker task-specific dust exposures (n = 41) were measured in three factories using conventional filter method. Additionally, toxic metal levels in the coating powder (n = 27) were analyzed to assess hazard potentials. Continuous monitoring of airborne respirable dust levels indicated large temporal variation across a normal working day. The particulate levels outside spraying booths were generally low (below 0.10 mg m-3) during normal spraying operation, but short-term level may reach as high as 21.8 mg m-3 (averaged at 4-5 mg m-3) when specific task such as cleaning the pipelines and spraying booth, was performed. Exploratory assessment on particle size distribution at four major working zones, administration, uploading, spraying, and baking, indicated no major difference among the zones, and between factories. The particle count median aerodynamic diameter was 0.88-1.69 µm, while the mean number concentrations were 10.97, 15.17, 18.49, and 27.03 (# cm-3) for zones administration, uploading, spraying, and baking, respectively. The worker task-specific dust exposures were found low during normal spraying, with the mean short-term total and respirable dust concentrations being 0.88 and 0.41 mg m-3, respectively. Both levels increased to 3.48 and 5.19 mg m-3, respectively (P < 0.05), if powder changing and system cleaning were done. Short-term total and respirable dust concentrations were 94.2 and 56.1 mg m-3, respectively, when complete cleaning process was performed inside spraying booth. Both levels exceeded the short-term exposure limits. The mean concentration of metals in the powder samples were 6.78, 9.52, 10 717, 2805, 1020, and 1361 µg g-1 for Pb, Cr (total), Al, Fe, Cu, and Sr, respectively. This study demonstrated that cleaning of spraying booth resulted in high dust exposures well exceeding the exposure limit. Toxic metals, particularly Pb, Cd, and Cr (total), levels measured in the powder samples were found low, and the resulting exposures were below the exposure limits, indicating relative low risks associated with the exposure at current dust levels.

Control measures for airborne ammonia and respirable dust exposure in swine barns

ABSTRACT Extended exposure to airborne contaminants such as ammonia (NH3) and respirable dust in swine facilities has been associated with various health problems among swine barn workers. The overall goal of this study was to assess the impact of selected control measures, namely, canola oil sprinkling, low crude protein diet, high level of cleaning, and manure pH manipulation, on NH3 and respirable dust concentrations in swine production rooms through area sampling and on worker exposure to these contaminants in accordance with National Institute of Occupational Safety and Health (NIOSH) methods for occupational exposure monitoring. Results from five trials showed that low crude protein diet can be used for reducing worker exposure to NH3 while oil sprinkling can be used for controlling respirable dust levels in swine rooms. Reduction in airborne levels did not translate to reduction in occupational exposure. Commercial NH3 monitors showed higher readings than the standard NIOSH 6015 method.

Underground Gold Miner Exposure to Noise, Diesel Particulate Matter and Crystalline Silica Dust.

Background.Respirable dust, diesel particulate matter, crystalline silica and noise pollution are the most common causes of health issues experienced by underground mine workers. Assessment of exposure levels in relation to standard regulatory body permissible levels is essential for the safety of mine workers.Objectives.The present study compared exposure levels of diesel particulate matter, crystalline silica dust and noise experienced across different underground mine worker job titles.Methods.Subjective sampling was employed using gravimetric air samplers over an 8-hour time weighted average for two periods designated as period 1 (first half of the year) and period 2 (second half of the year). A comparative analysis of exposure levels between job titles and in relation to the National Institute for Occupational Safety and Health (NIOSH) permissible exposure levels (PELs) was performed.Results.In the present study, 90% of the selected job titles were over-exposed to noise and 80% were over-exposed to diesel particulate matter. The highest exposures for crystalline silica dust and diesel particulate matter were found in the 40–49-year-old age group.Conclusions.The present study of exposure levels of diesel particulate matter, respirable dust, crystalline silica, and noise during underground gold mining demonstrates that better control mechanisms are needed to protect workers.Participant Consent.ObtainedEthics Approval.This study was approved by the Ethics Committee of the Kwame Nkrumah University of Science and Technology, Ghana.Competing Interests.The authors declare no competing financial interests.

Association between Respirable Dust Exposure and Lung Function Deterioration among Construction Site Workers

Construction workers are at risk of developing respiratory health problems because they are exposed to various forms of dust at the construction site. This study aimed to evaluate the exposure to respirable dust level and respiratory health of construction site workers. Personal Air Sampling Pump was used to determine the exposure to respirable dust. Meanwhile, the spirometry test was performed to assess the efficiency of the lung function. Based on independent T-test, the exposed workers showed significantly higher exposure to respirable dust level than nonexposed workers. The lung function parameters (FVC%, FEV1% and FEV1/FVC%) were lowered significantly among the exposed workers compared to the non-exposed workers. Cough and phlegm have been reported to be the most probable symptoms determined among the construction workers. In conclusion, personal exposure to high level of respirable dust increased the risk of lung function deterioration.

Exposure to Mild Steel Welding and Changes in Serum Proteins With Putative Neurological Function-A Longitudinal Study.

Welders are exposed to high levels of metal particles, consisting mainly of iron and manganese (Mn) oxide. Metal particles, especially those containing Mn can be neurotoxic. In this exploratory study, we evaluated associations between welding and expression of 87 putative neurology-related proteins in serum in a longitudinal approach. The study cohort from southern Sweden included welders working with mild steel (n = 56) and controls (n = 67), all male and non-smoking, which were sampled at two timepoints (T1, T2) 6-year apart. Observed associations in the longitudinal analysis (linear mixed models) were further evaluated (linear regression models) in another cross-sectional sample which included welders (n = 102) and controls (n = 89) who were sampled only once (T1 or T2). The median respirable dust levels for welders after adjusting for respiratory protection was at T1 0.6 (5–95 percentile: 0.2–4.2) and at T2 0.5 (0.1–1.8) mg/m3. The adjusted median respirable Mn concentration was at T2 0.049 mg/m3 (0.003–0.314) with a Spearman correlation between adjusted respirable dust and respirable Mn of rS = 0.88. We identified five neurology-related proteins that were differentially expressed in welders vs. controls in the longitudinal sample, of which one (nicotinamide/nicotinic acid mononucleotide adenylyltransferase 1; NMNAT1) was also differentially expressed in the cross-sectional sample. NMNAT1, an axon-protective protein linked to Alzheimers disease, was upregulated in welders compared with controls but no associations were discerned with degree of exposure (welders only: years welding, respirable dust, cumulative exposure). However, we identified five additional proteins that were associated with years welding (GCSF, EFNA4, CTSS, CLM6, VWC2; welders only) both in the longitudinal and in the cross-sectional samples. We also observed several neurology-related proteins that were associated with age and BMI. Our study indicates that low-to-moderate exposure to welding fumes is associated with changes in circulating levels of neurology-related proteins.