Annals Of Work Exposures and Health最新文献

Background: Studies among workers with a wide range of exposure to perfluoroalkyl substances inform risk assessments. Perfluorooctane sulfonate (PFOS), a ubiquitous environmental contaminant, was recently examined in relation to mortality and cancer incidence in an occupationally exposed population by Alexander et al. in 2024. In that study, cumulative occupational exposure (mg/m3 PFOS-equivalents in air) was reconstructed using a job-exposure matrix and individual work history. While the exposure reconstruction had good face validity, an assessment of its performance in relation to serum PFOS levels would allow improved interpretation of the occupational epidemiology findings.

Objective: The objective of this study was to assess the validity of the exposure reconstruction used by Alexander et al. (2024).

Methods: A previous study by Olsen et al. (2003) measured serum PFOS levels in 1998 for 260 workers and because these workers were included in the epidemiologic study by Alexander et al. (2024), the study reported herein compared serum PFOS levels to those predicted using a simple compartmental pharmacokinetic model.

Results: The Pearson correlation coefficient between the observed and pharmacokinetic model-predicted serum PFOS concentration was 0.80 (95% confidence interval, 0.75 to 0.84). The median ratio of predicted to observed serum concentrations was 12 (i.e. actual exposure was significantly less than predicted). The predicted serum PFOS concentrations were not sensitive to the parameters used in the pharmacokinetic model other than exposure concentration or absorption.

Conclusions: The model did not predict absolute exposure well, probably because of personal protective equipment use not being accounted for and absorption of PFOS or precursors being lower than modeled. On the other hand, the model did a reasonably good job of ranking the workers' exposure, thus classification of workers according to relative amount of cumulative PFOS-equivalents was reasonably accurate in the study by Alexander et al. (2024) when validated using the measured serum PFOS data.

Objectives: Exposure to microorganisms is a known contributor to occupational disease. This study assessed drilling waste workers' health status and investigated the potential of inhalable bioaerosols to elicit an immune response in vitro and in vivo.

Methods: Venous blood and self-reported health data were collected from 56 and 73 Norwegian drilling waste workers, respectively. Immunological effects were assessed as Toll-like receptor (TLR) activation potential of personal air samples in vitro and biomarker expression in workers' plasma samples in vivo. Parameters, such as BMI, sex, and smoking habits, were considered along with factors such as purification technology of drilling waste when biomarker expression was interpreted. Symptom prevalence among exposed workers was compared to an unexposed control group.

Results: Personal air samples activated TLR signalling in vitro in 90% of all cases. The activation potential correlated significantly with work exposure to microbial agents and total dust. Significant differences in biomarker expression and symptom prevalence were identified between purification technologies and exposure groups. Drilling waste workers had significantly increased OR of skin irritation and respiratory symptoms compared to the control group.

Conclusions: Exposure to microorganisms during the treatment of offshore drilling waste is an occupational health concern.

In the summer season, road construction workers perform physically demanding tasks outdoors, placing them at greater risk for exertional heat illness conditions. Assessing core temperature (Tcore) is critical as it serves as a key indicator of heat strain and helps to estimate the risk of heat-related illness. Despite the increased risk of hyperthermia, previous research has not assessed Tcore in road construction workers in the United States during summer work.

Purpose: To report heat strain and environmental heat stress in a pilot study of road construction workers during work in the summer.

Methods: Seven male road construction workers in New Mexico were observed performing physically demanding work during a summer work shift. Environmental heat stress (heat index [HI], dry/wet bulb temperature, and relative humidity), Tcore, and skin temperature (Tskin) were measured continuously at a single job site throughout the workday. Hydration was assessed pre- and post-shift via measurements of urine specific gravity (USG) and changes in body weight.

Results: The peak HI recorded throughout the workday was 34.1 °C, corresponding to a "warning" heat risk level according to the Occupational Safety and Health Administration Heat Safety Tool App. Two of seven (29%) workers reached a peak Tcore of greater than 38.0 °C, and 4 (57%) began the work shift dehydrated, indicated by a USG >1.020.

Conclusions: Findings from this pilot study suggest that road construction workers may begin their shifts dehydrated and some experience moderate hyperthermia while performing physically demanding work in hot environmental conditions.

Introduction: Overexposure to respirable crystalline silica (RCS) can lead to the development of silicosis and other respiratory diseases. The mine under study was reported to have the highest number of certified cases of pneumoconiosis in Zambia in 2015, and in 2008, a study revealed that 56% of the RCS samples exceeded 0.05 mg/m3. This study aims to assess occupational exposure to RCS at this underground copper mine.

Method: In this cross-sectional study, personal exposure monitoring was conducted using National Institute for Occupational Safety and Health's methods 0600 and 7602 (KBr pellet), and 114 samples were collected. Gravimetric analysis of respirable dust (RD) samples and quantification of RCS were performed at an ISO 17025:2005 accredited analytical laboratory. BOHS-NVvA 2022 standard was used for determining activity areas' overexposure.

Results: The median, 95th percentile (P95), and maximum (Max) RD concentrations were 0.279, 1.650, and 3.7 mg/m3, respectively. For the RCS exposure, the median, P95, and Max RCS exposure concentrations were 0.02, 0.179, and 0.548 mg/m3, respectively. Thirteen (11.7%) of the 111 samples had exposure exceeding the Republic of South Africa (RSA) TWA-OEL of 0.1 mg/m3, and 11 out of 18 activity areas were statistically overexposed to RCS when applying the BOHS-NVvA 2022 standard.

Discussion: The number of RCS samples exceeding 0.05 mg/m3 reduced from the 67% recorded in 2008 to 32.4% in this study. One factor that could have led to this reduction is the mine not working at full capacity during the sampling period. However, the lack of adherence to the occupational health and safety (OHS) guidelines by the miners still leads to personal exposure above the limits set by various countries.

Conclusion: Exposure to RCS in more than half of the activity areas was not under control. Routine RCS monitoring in Zambian mines should be mandatory, as this is not an isolated case, though it is more of a challenge at this mine because of the high percentage of RCS in RD samples (18.5%). Miners should be continuously trained on the importance of adhering to the OHS guidelines. Furthermore, Zambia should consider adopting the RSA occupational exposure limit for RCS and the BOHS-NVvA 2022 standard for exposure level compliance testing.

Introduction: US home care (HC) aide visits to clients' homes typically involve cleaning and disinfecting (C&D) environmental surfaces, particularly in bathrooms. Some ingredients in C&D products are associated with respiratory illness: sodium hypochlorite (bleach), quaternary ammonium compounds (QACs), and volatile organic compounds (VOCs). This study assessed and compared aides' respiratory exposures to specific VOCs and QACs while using 2 conventional and 1 "green" household C&D spray products during bathroom cleaning. Measured exposures were compared to ingredients listed on publicly available sources.

Methods: Three C&D products were selected with principal active disinfecting ingredients: 1% to 5% sodium hypochlorite by weight ("bleach-based"); 0.1% to 1% QACs ("QACs-based"); and 0.05% thymol ("green"). Twenty-two aides were recruited to perform C&D tasks in a simulated residential bathroom constructed in an environmental monitoring laboratory. A balanced experimental study design involved each aide visiting the lab 4 times to perform typical cleaning tasks with the 3 products and distilled water (as a control), randomly assigned across the 4 visits. Aides wore air sampling equipment for breathing zone samples: canisters to collect whole air for VOC analyses and filter cassettes for QACs analyses.

Results: Aides performed 84 cleaning visits contributing approximately 20 air samples each for VOCs and QACs, for each of the 3 products and distilled water. In total, 38 unique VOCs were identified in the canister whole air samples: 20 in the QACs-based product samples, 15 in the bleach-based, and 10 in the green. Most VOCs were not listed in publicly available sources of cleaning product ingredients. Toxicity information was limited. Few VOCs had occupational exposure limits. The QACs-based product generated QACs aerosol: benzalkonium chloride (BAC)12 (geometric mean (GM) = 6.98 µg/m3), BAC14 (GM=2.97 µg/m3), BAC16 (GM=0.78 µg/m3); and the 3 QACs summed (GM=10.86 µg/m3).

Discussion: The use of C&D spray products for residential cleaning can generate respiratory exposures to complex mixtures of volatile and nonvolatile compounds. Notably, we measured aerosols containing QACs during the use of the QACs-based product. Dermal is usually considered the main route of exposure because QACs are nonvolatile salts. This study provides evidence that QACs inhalation exposure should be recognized and minimized in addition to the well-accepted dermal exposure routes. The green product generated the fewest VOCs. However, more toxicity information is needed on the health impacts of green C&D products. Spraying of C&D products, conventional and green, should be avoided.

Conclusions: Aides' respiratory health should be protected from chemical exposures while performing C&D in home care.

Recent studies highlight brickmaking's environmental and biological impacts, ranging from environmental pollution to toxic exposures in brickmakers and residents of neighboring areas. However, the risk of infections associated with brickmaking is widely understudied. In low- and middle-income countries worldwide, the brickmaking industry often belongs to the informal labor sector. Many of the millions of individuals in the industry belong to disenfranchised groups affected by adverse determinants of health. Manual brickmaking is precarious and exposes workers to infectious risks, yet this field remains understudied. This manuscript aims to raise awareness of these infectious risks and calls for comprehensive research to understand and mitigate them.

Introduction: Mining is a high-hazard industry with significant occupational disease risks. Despite this there is limited data describing current exposure conditions. The aim of this short communication is to share recent exposure data from underground mines in Ontario, Canada.

Methods: Data from underground mines were accessed through a freedom of information request. Data were cleaned and standardized. Data contained measurements of several hazards from 2013 to 2018; analysis focused on personal samples for respirable crystalline silica (RCS) and elemental carbon (EC) from 2014 to 2018. Descriptive statistics were calculated overall and by sampling year; comparisons were made to current occupational exposure limits. Linear regression models were constructed to examine time trends.

Results: EC exposures decreased significantly, ~10% per year over the measurement period (2014 to 2018). Overall 14% of EC measurements were above the current mining exposure limit (0.12 mg/m3 EC) in Ontario, Canada. Results for silica did not show a statistically significant trend but did suggest a reduction of ~1.8% per year. Almost one-third of the RCS measurements were above the American Conference of Governmental Industrial Hygienists (ACGIH) recommended threshold (0.025 mg/m3).

Conclusions: Current exposure data is needed to understand workers' exposure and support occupational disease prevention. Recent data from the Ontario mining industry suggests that exposure to elemental carbon decreased significantly from 2014 to 2018, but the annual reduction for silica exposure was not nearly as substantial. Mining workers continue to be exposed to levels of EC and RCS that are hazardous to health.

In the scope of the European Union (EU) human biomonitoring initiative, a multicentric study on different occupational settings from several European countries was performed, to provide information on occupational exposure to hexavalent chromium [Cr(VI)], a known lung carcinogen. Biomonitoring approaches were used to obtain exposure data to support the implementation of new risk management measures and policy actions at the national and European levels. This work describes the Portuguese contribution to the study, which aimed to assess workers' exposure to Cr, by using exposure biomarkers (urinary chromium [U-Cr]), and industrial hygiene samples (air and hand wipes) and to link exposure to potential long-term health effects by using effect biomarkers. Exposure determinants influencing exposure were explored from the contextual information and human biomonitoring data. The ultimate goal of the study was to appraise the risk management measures contributing to minimize exposure and protect workers' health. Several occupational settings and activities were considered, including plating, welding, and painting. A control group from the Portuguese general population was also included. Data on age, sex, and smoking habits from both groups were considered in the statistical analysis. Information on the risk management measures available for workers was collected and used to identify the ones that mainly contributed to reduce exposure. Environmental monitoring and human biomonitoring revealed that painters were the highest exposed group. The use of respiratory protection equipment showed an influence on total U-Cr levels for workers involved in painting activities. Concerning early health effects, the painters presented also a significantly higher level of DNA and chromosomal damage in peripheral blood cells, as compared to the control group, suggesting a plausible association between exposure to Cr(VI) and early genotoxic effects. The results showed that workers are exposed to Cr(VI) in those occupational settings. These findings point to the need to improve the prevention and risk management measures and the implementation and enforcement of new regulatory actions at the national level.

Introduction: Very little is known about the effects on the health of work as a wildland firefighter over repeated fire seasons. In Alberta, where the fire season runs from 1 March to 31 October, the great majority of firefighters are hired seasonally. We examined whether there was a dose-response relationship between hours of firefighting and ill-health.

Methods: A cohort was established linking employment records from Alberta Wildfire to administrative health data and cancer records. The employment records contained information on each deployment for all firefighters with employment from 1998 to 2022. Health records had details of diagnoses recorded at all physician consultations for the same period. Cancer records included diagnostic information for all confirmed cancers in the province. Exposure indices (hours worked) were related to health outcomes, with relative risk estimated by multilevel Poisson regression, using data lagged by 10 years for cancer outcomes.

Results: Of 16,816 firefighters with employment records, 12,731 were matched on name, age, and sex in health records and were living in Alberta at the end of at least one fiscal year. One in three had only been employed for one fire season with 10% employed in 10 or more years. The overall mean cumulative exposure was 795 h with 568 h of sustained attack (SA). In multivariable regression, adjusted for age, sex, and inferred First Nation origin, the risk of chronic obstructive pulmonary disease (COPD) and pneumonia increased with hours of firefighting on foot and decreased with fighting less complex fires or holding a permanent appointment. Hours of firefighting in the year of health report were protective for cardiovascular disease (CVD) and mental ill-health but the risk of injury from external causes increased with firefighting hours. The risk of COPD, pneumonia, and asthma increased with cumulative hours over multiple fire seasons of SA firefighting and decreased with cumulative hours fighting less complex fires. Risks of CVD and mental ill-health were also positively related to cumulative hours of SA. No increase in risk was found with cancer incidence (all cancers, bladder cancer, lung cancer, skin: melanoma or nonmelanoma), with exposures unlagged or lagged by 10 years.

Conclusion: Wildland firefighters were found to be at increased risk of lung conditions, both acutely in the year of firefighting and in subsequent years. No increased risk was found for cancer.

Objectives: Information systems focusing on occupational carcinogen exposure, whether categorized by industry or occupation, play a pivotal role in the prevention of occupational cancers. Recently, the Korean CARcinogen EXposure (K-CAREX) system was developed to assess carcinogen exposure by industry. However, corresponding information categorized by occupation has yet to be developed. This study aimed to develop an occupation-based exposure matrix for occupational carcinogens as an extension of the K-CAREX framework.

Methods: The Work Environment Measurement Database (WEMD) and the Special Health Examination Database (SHED) were combined to estimate exposure intensity by occupation. The WEMD supplied exposure levels, whereas the SHED provided occupation information. Additionally, the SHED served as the primary data source for constructing an indicator of exposure prevalence by occupation, utilizing standard occupational classification.

Results: A total of 22 carcinogens were selected for evaluating exposure intensity, and 20 carcinogens were selected for assessing exposure prevalence. Exposure intensity and prevalence were assigned to 156 occupational groups based on these carcinogens. For instance, in terms of welding fume exposure, welders were assigned an exposure intensity rating of 3 and exhibited exposure prevalence of 26%.

Conclusions: Our findings complement the previously developed K-CAREX, which offered an industry-based exposure matrix. The resultant comprehensive K-CAREX, incorporating both industry- and occupation-based matrices, can be utilized for occupational cancer prevention and epidemiological studies.