Cross-shift Changes Research Articles

Cross-shift changes in pulmonary function and occupational exposure to particulate matter among e-waste workers in Ghana.

Little is known on the association between cross-shift changes in pulmonary function and personal inhalation exposure to particulate matter (PM) among informal electronic-waste (e-waste) recovery workers who have substantial occupational exposure to airborne pollutants from burning e-waste. Using a cross-shift design, pre- and post-shift pulmonary function assessments and accompanying personal inhalation exposure to PM (sizes <1, <2.5 μm, and the coarse fraction, 2.5-10 μm in aerodynamic diameter) were measured among e-waste workers (n = 142) at the Agbogbloshie e-waste site and a comparison population (n = 65) in Accra, Ghana during 2017 and 2018. Linear mixed models estimated associations between percent changes in pulmonary function and personal PM. Declines in forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) per hour were not significantly associated with increases in PM (all sizes) among either study population, despite breathing zone concentrations of PM (all sizes) that exceeded health-based guidelines in both populations. E-waste workers who worked "yesterday" did, however, have larger cross-shift declines in FVC [-2.4% (95%CI: -4.04%, -0.81%)] in comparison to those who did not work "yesterday," suggesting a possible role of cumulative exposure. Overall, short-term respiratory-related health effects related to PM exposure among e-waste workers were not seen in this sample. Selection bias due to the "healthy worker" effect, short shift duration, and inability to capture a true "pre-shift" pulmonary function test among workers who live at the worksite may explain results and suggest the need to adapt cross-shift studies for informal settings.

Respiratory symptoms and pulmonary function impairment among textile industry workers in Alexandria, Egypt.

Occupational exposure to cotton dust is still an important cause of respiratory problems in textile workers particularly in less developed countries like Egypt. Evaluate respiratory symptoms and diseases, and pulmonary function pattern among Egyptian textile workers. Cross sectional comparative study was conducted from December 2019 to September 2020 in a textile factory in Egypt; 364 male workers (184 cotton dust exposed workers, and 180 unexposed workers) were included. Participants were subjected to an interviewing questionnaire, British Medical Research Council questionnaire, anthropometric measurements, pulmonary function tests, and byssinosis grading format. Descriptive and analytic statistics were conducted. Chronic cough, phlegm production, and shortness of breath grade I, II and III were more reported in cotton dust exposed workers than unexposed workers (P#x003C;0.01, P#x003C;0.01, and P=0.02, respectively). Prevalence of chronic bronchitis was significantly higher among cotton dust exposed workers (12%) than unexposed workers (3.9%) (P#x003C;0.01). The mean percent predicted values of lung function indices reflecting large-1irway function (VC, FVC, FEV1, FEV1%, PEFR, and FEF75) were significantly lower in cotton dust exposed workers (P#x003C;0.01). Prevalence of byssinosis was 22.8%. Workers with byssinosis had significantly higher prevalence of respiratory symptoms, chronic bronchitis, cross-shift reduction in PEFR and significant decrease in mean percent predicted values of FVC, FEV1, PEFR, FEF75, and FEF50 than workers without byssinosis. This study revealed a substantial association between cotton dust exposure at work and respiratory symptoms and morbidity. Regular measurement of cross shift change in PEFR is recommended among exposed workers for early diagnosis of byssinosis.

A comprehensive evaluation of heat stress and heat strain in a sample of sugarcane cutters in Brazil.

Sugarcane cutters are vulnerable to extreme heat and are at risk for heat-related illness and chronic kidney disease, potentially due to high heat strain. We performed a comprehensive assessment of the physiological demands of sugarcane cutters via measurements of metabolic, thermal, and cardiovascular responses. In addition, we assessed cross-shift changes in markers of kidney function. Nine male sugarcane cutters were monitored while working during the spring harvest season in Brazil. Core temperature (Tcore) and heart rate (HR) were continuously recorded, and oxygen consumption was measured during the work shift. Urine and blood samples were collected pre- and postwork shifts. Total sweat loss was calculated using body weight changes and adjusting for water ingestion and urine output. A wet-bulb globe temperature (WBGT) station was used to monitor environmental heat stress. WBGT was ≥30°C on 7 of the 8 study days. Mean and peak Tcore during the work shift were 37.96 ± 0.47°C and 38.60 ± 0.41°C, respectively, with all participants surpassing a Tcore of 38°C. Mean and peak HR during the work shift were 137 ± 14 and 164 ± 11 beats/min, respectively. Percent of maximal oxygen consumption was, on average, 53 ± 11%. Workers had a total sweat loss of 7.63 ± 2.31 L and ingested 6.04 ± 1.95 L of fluid. Kidney function (estimated glomerular filtration rate) was reduced from pre- to postwork shift (Δ -20 ± 18 mL·min·1.73 m2). We demonstrated that sugarcane cutters performing prolonged work during a period of high environmental heat stress display high levels of heat strain, high water turnover, and reduced kidney function.NEW & NOTEWORTHY We demonstrate that a shift of sugarcane cutting performed outdoors during the spring harvest season results in a high level of heat strain. In fact, all the studied workers sustained core temperatures above 38°C and heart rates above 75% of the measured maximum heart rate. Additionally, workers displayed a high water turnover with sweat loss close to 10% of their body weight. Finally, we report elevated muscle damage and reductions in kidney function following the work shift.

Measurement of Diacetyl and Related Compounds in Coffee Roasteries and Breweries.

α-Diketones such as diacetyl (2,3-butanedione) and 2,3-pentanedione are generated during the roasting and fermentation of foods and are also used as flavoring compounds. Exposure to these compounds has been associated with obliterative bronchiolitis in workers. We report indoor air concentrations of diacetyl and 2,3-pentanedione, as well as acetoin (3-hydroxy-2-butanone), in several small coffee roasteries and breweries using standard integrated air sampling sorbent tubes followed by gas chromatography tandem mass spectrometry as well as the first use of on-site continuous real-time proton-transfer reaction time-of-flight mass spectrometry (PTR-ToF-MS). Diacetyl and 2,3-pentanedione were detected in most of the sorbent samples at concentrations between 0.02 and 8 ppbv, and in general were higher in coffee roasteries compared with breweries. Three integrated air samples, all from the barista area at one facility, exceeded the NIOSH recommended exposure limit (REL) of 5 ppbv for diacetyl. 2,3-Pentanedione concentrations in these three samples were greater than 50% of its REL, but did not exceed it. Acetoin, a precursor to diacetyl, was also detected at concentrations between 0.03 and 5 ppbv in most sorbent tube samples, with concentrations generally higher in breweries. PTR-ToF-MS measurements exhibited similar trends and provided continuous real-time volatile organic compound data that showed episodic excursions with peak concentrations of diacetyl and 2,3-pentanedione between 15 and 20 ppbv. Examination of the time series data identified specific activities associated with peak diketone emissions, including transfer of freshly roasted coffee beans to the cooling tray, or the opening of a brew kettle. Additional indoor air quality parameters including CO2, NO2, and PM2.5 were also assessed on-site. Airway inflammation was assessed in 19 workers before and after each work shift using online measurements of fractional exhaled nitric oxide (FENO). The pre-shift mean FENO was 3.7 (95% confidence interval: -3.6, 11.0) ppbv higher and the post-shift FENO was 7.1 (-1.9, 16.1) ppbv higher for workers at coffee roasteries compared with breweries. The cross-shift change in FENO was 3.4 (-2.8, 9.6) ppbv higher for workers at coffee roasteries compared with breweries. However, none of these differences were statistically significant, and the cross-shift change in FENO was not statistically different from zero for either group of workers. The findings from this pilot study demonstrate that α-diketones and related compounds are present in the indoor air of both breweries and coffee roasteries and may exceed health protective guidelines in coffee roasteries. Additional studies are required to fully characterize worker exposures in these settings and to identify specific work activities and processes associated with high exposures. Engineering controls, including targeted exhaust ventilation and the use of low-cost sensors, are recommended as an approach to protect workers from exposure to hazardous levels of α-diketones.

Effect of Wildland Fire Smoke Exposure on Acute Cardiovascular Responses among Wildland Firefighters Working at Prescribed Burns

BACKGROUND AND AIM: Wildland firefighters at prescribed burns are exposed to elevated levels of wildland fire smoke (WFS) while performing physically demanding tasks. WFS exposure has been linked to increase in hospital/emergency admission for cardiovascular disorders in the general population. Working arduously in high heat-stress conditions also places a great demand on the cardiovascular system. However, knowledge about the cardiovascular effect of occupational WFS exposure during prescribed burns among wildland firefighters is relatively limited. METHODS: Between 2016 and 2019, a total of 38 wildland firefighters (34 males and 4 females, an average age of 35.63 ± 9.31 years and a firefighting career length of 9.08 ± 7.94 years) employed by the USFS–Wayne National Forest and the Ohio Department of Natural Resources–Division of Forestry participated in this study. Resting systolic/diastolic blood pressure (SBP/DBP) and heart rate (HR) of wildland firefighters were measured before (pre-shift), after (post-shift), and the morning (next-morning) following prescribed burn shifts (burn days) and regular work shifts (non-burn days). RESULTS:On burn days, HR significantly increased from pre- to post-shift (p0.01) while SBP significantly decreased in the morning following the prescribed burns compared to pre-shift (p=0.04). However, this was due to the decrease of SBP in the firefighters who were hypertensive. Significant cross-shift reductions were observed in SBP on burn days compared to non-burn days (p0.01). A significant reduction on burn days was also observed from pre-shift to next-morning for HR compared to non-burn day (p=0.02) while HR significantly increased in pre- to post-shift on burn days compared to non-burn days (p0.01). CONCLUSIONS:Cross-shift changes in SBP and HR might be attributable to WFS exposure and physical exertion during the prescribed burns. The results suggest that wildland firefighting exposure might cause a distinct hemodynamic response, including SBP reduction and HR increment, especially for those who had pre-existing hypertension. KEYWORDS: Air pollution, Wildfires, Occupational exposures, Occupational epidemiology.

Urinary biomonitoring of occupational exposures to Bisphenol A Diglycidyl Ether (BADGE) - based epoxy resins among construction painters in metal structure coating.

Epoxy resin systems based on Bisphenol A Diglycidyl Ether (BADGE) monomer and its higher oligomers are important commercial formulations used widely in construction for protective coating of steel structures, such as bridges. The literature on occupational exposures and biomonitoring of BADGE-based epoxies among construction painters is remarkably limited. In this first occupational biomonitoring study of epoxies, 44 construction painters performing mid- and top-coating were recruited from 12 metal structure coating sites in New England. Cross-shift changes in the urinary levels of total BADGE and its three major hydrolysis derivatives - BADGE·2H2O, BADGE·H2O, BADGE·HCl·H2O - were assessed. Results for 81 urine samples collected from coating workers were compared with 28 urine samples of a reference group of 14 spray polyurethane foam (SPF) insulation workers. The highest concentrations of all biomarkers were found in the urine samples of mid-coat applicators. The major urinary biomarker of BADGE in this cohort of workers, BADGE·2H2O, was detected in 100% of urine samples. The post-shift BADGE·2H2O (specific gravity normalized data) in mid-coat applicators had a geometric mean (GM) of 1.46ng/mL and a geometric standard deviation (GSD) of 3.6 (range, 0.2-18.7ng/mL). The second most abundant biomarker in urine, BADGE·HCl·H2O, was measured in 84% of samples, and had a post-shift GM(GSD) of 0.17 (2.3) ng/mL (range, <0.025-0.59ng/mL). BADGE·2H2O was 8.6 times more abundant than BADGE·HCl·H2O. BADGE·H2O was quantified only in 10% of the samples (range, 0.11-0.41ng/mL). Free BADGE in post-shift urine, corrected for background, had GM (GSD) of 0.04 (2.5) ng/mL (range, <0.025-0.16ng/mL). Urinary BADGE·2H2O were significantly higher (p=0.01) in mid-coat applicators compared to top-coat and SPF workers. Post-shift urinary BADGE·2H2O in mid-coat applicators increased by ~2.9× (p=0.02) and 1.36× in top-coat applicators (p=0.18) compared to pre-shift values, but not in SPF workers (0.95×; p=0.40). In conclusion, we demonstrate that (i) significant BADGE uptake occurs via inhalation and skin exposures during application of epoxy-containing paintings (mid-coat), suggesting the need for improvements in hygiene practices and personal protective measures; (ii) BADGE·2H2O is a robust and sensitive biomarker for biomonitoring of exposures to BADGE-based epoxies in occupational settings; and (iii) widespread occurrence of BADGE and BADGE·2H2O in the urine of all workers, including SPF workers, suggest common exposures from non-occupational sources, such as ingestion or do-it-yourself consumer applications of epoxy resins. In light of this observation, establishing a reliable biological monitoring guidance value (BMGV) for BADGE·2H2O will require more background biomonitoring and health effect data. An initial reference value for BADGE·2H2O of 0.5ng/mL (SG-normalized) or 180nmol/mol creatinine is being proposed as the threshold to discriminate occupational from non-occupational exposures based on the maximum values observed in the reference SPF group.

Urinary mutagenicity and oxidative status of wildland firefighters working at prescribed burns in a Midwestern US forest

ObjectiveWildland firefighters (WLFFs) experience repeated exposures to wildland fire smoke (WFS). However, studies about WLFFs remain regionally limited. The objective of this study was to assess the effect of WFS...

Cross-Shift Changes in Pulmonary Function and Occupational Exposure to Particulate Matter among E-Waste Workers in Ghana

Objectives: To examine the association between cross-shift changes in pulmonary function (PF) and personal inhalation exposure to particulate matter (PM) among informal electronic-waste (e-waste) recovery workers with substantial occupational exposure to airborne pollutants from burning and other e-waste recovery activities.Methods: Using a cross-shift design, pre- and post-shift spirometry and concomitant personal inhalation exposure to personal PM (sizes &lt;1, &lt; 2.5, and the coarse fraction, 10-2.5 µm in aerodynamic diameter) were measured among e-waste workers (n=142) at the Agbogbloshie e-waste site and a comparison population (n=65) in Accra, Ghana. Linear mixed models measured associations between percent changes in PF and personal PM; self-reported exposures; and (image-based) activities. Results: Following 4 hour (+ 44 min) work-shifts, decelerations in forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) per hour were observed among e-waste workers (2.2% and 1.2%, respectively) and the reference population (1.5% and 0.8%, respectively). Despite significantly higher concentrations of personal PM (all sizes) among e-waste workers, increases in PM (all sizes) were not associated with decelerations in PF in either group. Indicative of a lag-effect, e-waste workers who worked “yesterday” had a larger decrement in FVC (2.4%, 95%CI: -4.04, -0.81) in comparison to those that did not work “yesterday”.Conclusions: The acute respiratory-related health effects due to PM exposure among e-waste workers remains unclear. Limitations included potential selection bias due to the “healthy worker” effect and challenges in eliciting valid PF assessments among e-waste workers, short shift duration, the lack of an inception cohort, and inability to measure pre-shift PF among e-waste workers who sleep at the site (89%). Cross-shift studies are useful for generating robust evidence in traditional work settings; however, they need to be adapted to informal settings where workers do not “clock-in” at the start of a shift.

Cross-shift change of acute kidney injury biomarkers in sugarcane farmers and cutters

Sugarcane farmers and cutters have been reported to be at high risk of acute kidney injury. This cross-sectional study aimed to assess acute kidney injury biomarkers, and cross-shift change among 150 sugarcane cutters and 98 sugarcane farmers in Thailand. Physical health examination, environmental measurements, and measured urinary neutrophil gelatinase-associated lipocalin (NGAL) were assessed. Cross-shift change of urine creatinine (uCr), albumin creatinine ratio (ACR), and NGAL between sugarcane farmers and cutters was compared. Factors influencing abnormal post-shift ACR and NGAL were analyzed by binary logistic regression adjusted with covariates. Sugarcane cutters were significantly more likely to take nonsteroidal anti-inflammatory drugs (NSAID) and herbs to relieve pain than sugarcane farmers. Males were more likely to be current smokers and drinkers although 62% of cutters and 56% of farmers were female. Sugarcane farmers and cutters had similar post-shift estimated glomerular filtration rate (eGFR) and ACR levels. Cross-shift measurements showed that both sugarcane cutters and sugarcane farmers had significantly higher post-shift geometric mean (GM) urinary NGAL, but that the cross-shift changes of NGAL were significantly higher for sugarcane cutters (182%) vs. sugarcane farmers (112%). Water intake less than recommendation of subjects was a significant predictor of a higher risk for an abnormal post-shift ACR after controlling for covariates, while being a sugarcane cutter was a predictor of a lower risk of an abnormal risk of a post-shift NGAL after controlling for covariates. Measurements of heat stress (WBGT plus workload) found that sugarcane cutters exceeded recommended exposures while sugarcane farmers were compliance to the TLV. These findings suggest that to protect sugarcane farmers and cutters, preventative measures are needed.

Allergic and Respiratory Symptoms in Employees of Indoor Cannabis Grow Facilities.

While little is known about the occupational hazards associated with Cannabis cultivation, both historical research in the hemp industry and preliminary data from modern grow houses, suggest that Cannabis workers may be at increased risk of respiratory and allergic diseases. We sought to investigate the association between workplace exposures and health symptoms in an indoor Cannabis grow facility in Washington State, USA. We performed a cross-sectional study with all consenting employees in an indoor Cannabis grow facility in Seattle, WA using a questionnaire. The questionnaire gathered data on respiratory, ocular, nasal, and dermal symptoms. A subset of employees with work-related symptoms underwent repeated cross-shift and cross-week measurement of spirometry, fractional exhaled nitrogen oxide (FeNO), and skin prick testing for Cannabis sensitization. Exposure to Cannabis dust was classified based on self-described tasks, expert opinion, and exposure monitoring of particulate matter. Multivariable logistic regression was undertaken to examine associations between exposure to Cannabis dust (classified as low, medium, and high) and health symptoms. Linear mixed effects models examined the relationship between cross-shift and cross-week changes in spirometry and FeNO. Ninety-seven percent (97%) of the employees (n = 31) surveyed were recreational cannabis users, with 81% (n = 25) smoking cannabis multiple times per day. Twenty-two (71%) employees reported one or more work-related symptoms: 65% respiratory, 39% ocular, 32% nasal, and 26% dermal symptoms. There was a trend toward increased likelihood of work-related symptoms with increasing exposure to Cannabis dust, although none of these results were statistically significant. Of the 10 employees with work-aggravated symptoms, 5 had borderline-high or high FeNO, 7 had abnormal spirometry, and 5 had evidence of Cannabis sensitization on skin prick testing. FeNO increased by 3.78 ppb (95% confidence interval 0.68-6.88 ppb) across the work-week and there was a trend toward cross-week and cross-shift reduced airflow. We found a high prevalence of work-related allergic- and particularly respiratory symptoms in the employees of one indoor Cannabis grow facility in Washington State. A high proportion of employees with work-aggravated symptoms had findings consistent with probable work-related asthma based on high FeNO, airflow obstruction on spirometry, and Cannabis sensitization on skin prick testing. However, due to the high incidence of recreational cannabis use among these workers, the relative influence of occupational versus recreational exposure to Cannabis dust on the respiratory health and sensitization status of these workers could not be resolved in this study.

Association between diesel engine exhaust exposure and lung function in Australian gold miners.

Previous studies have reported that miners (and other workers) exposed to high levels of diesel engine exhaust (DEE) have an increased risk of lung function decline. The main objective of this study was to evaluate associations between exposure to different components associated with DEE in relation to lung function across a 12-h working shift. Eighty underground gold miners and twenty surface miners completed spirometry and questionnaires at the beginning and end of their 12h work shift. Personal exposure to elemental carbon (EC), volatile organic compounds (VOCs), nitrogen dioxide (NO2), particle size and particle number were monitored during their shift. Multiple regression models were used to examine the associations between DEE and lung function, adjusting for a range of covariates. Underground miners were exposed to higher levels of EC, VOCs, NO2, and particle number and larger mean particle size than surface miners. Cross-shift reduction in Z-score value of FEV1/FVC in underground miners was statistically significantly greater than those of surface miners. The cross-shift change in Z-score value of FEV1/FVC was associated with exposure to higher concentration of EC and particle number, but not with VOCs, NO2 and particle size. Occupational exposure to diesel engine exhaust in current Australian gold mines is substantial. Exposures were higher in underground miners and had a negative association with their lung function over a single 12-h shift.

Chronic kidney disease of non-traditional origin in Mesoamerica: a disease primarily driven by occupational heat stress.

ABSTRACTThe death toll of the epidemic of chronic kidney disease of nontraditional origin (CKDnt) in Mesoamerica runs into the tens of thousands, affecting mostly young men. There is no consensus on the etiology. Anecdotal evidence from the 1990s pointed to work in sugarcane; pesticides and heat stress were suspected. Subsequent population-based surveys supported an occupational origin with overall high male-female ratios in high-risk lowlands, but small sex differences within occupational categories, and low prevalence in non-workers. CKDnt was reported in sugarcane and other high-intensity agriculture, and in non-agricultural occupations with heavy manual labor in hot environments, but not among subsistence farmers. Recent studies with stronger designs have shown cross-shift changes in kidney function and hydration biomarkers and cross-harvest kidney function declines related to heat and workload. The implementation of a water-rest-shade intervention midharvest in El Salvador appeared to halt declining kidney function among cane cutters. In Nicaragua a water-rest-shade program appeared sufficient to prevent kidney damage among cane workers with low-moderate workload but not among cutters with heaviest workload. Studies on pesticides and infectious risk factors have been largely negative. Non-occupational risk factors do not explain the observed epidemiologic patterns. In conclusion, work is the main driver of the CKDnt epidemic in Mesoamerica, with occupational heat stress being the single uniting factor shown to lead to kidney dysfunction in affected populations. Sugarcane cutters with extreme heat stress could be viewed as a sentinel occupational population. Occupational heat stress prevention is critical, even more so in view of climate change.

Risk Factors and Mechanisms Underlying Cross-Shift Decline in Kidney Function in Guatemalan Sugarcane Workers.

Identify early biomarkers and mechanisms of acute kidney injury in workers at risk of developing chronic kidney disease of unknown origin (CKDu). We assessed cross-shift changes in kidney function and biomarkers of injury in 105 healthy sugarcane workers. We obtained pre-harvest clinical data as well as daily environmental, clinical, and productivity data for each worker. The average percent decline in cross-shift estimated glomerular filtration rate (eGFR) was 21.8% (standard deviation [SD] 13.6%). Increasing wet bulb globe temperature (WBGT), high uric acid, decreased urine pH, urinary leukocyte esterase, and serum hyperosmolality were risk factors for decline in kidney function. Sugarcane workers with normal kidney function experience recurrent subclinical kidney injury, associated with elevations in biomarkers of injury that suggest exposure to high temperatures and extreme physical demands.

Cross‐shift Body Mass Change and Associated Health Outcomes Related to Chronic Kidney Disease in Sugarcane Workers in Guatemala

A new form of kidney disease, chronic kidney disease of an unknown origin (CKDu), has developed in Central America and other parts of the world. One group that is disproportionately affected are sugarcane workers potentially because of chronic dehydration and exercise heat stress.PURPOSEThe aim was to evaluate if changes in kidney health outcomes for three groups of sugarcane workers [highland sugarcane cutters (HC), local sugarcane cutters (LC), production workers (PW)] were related to the frequency of cross‐shift body mass change (&gt; 1% of body mass = dehydrated, body mass loss of ≤ 1% = hydrated).METHODS418 male sugarcane workers (HC n = 137, 28 ± 7 y, 159 ± 1 cm, 58.5 ± 6.0 kg, 0.88 ± 0.14 mg·dL‐1 whole blood creatinine (WBCr); LC n = 190, 32 ± 8 y, 161 ± 1 cm, 59.7 ± 8.4 kg, 0.92 ± 0.16 mg· dL‐1 WBCr; PW n = 91, 32 ± 11 y, 158 ± 1 cm, 60.1 ± 7.5 kg, 0.88 ± 0.16 mg· dL‐1 WBCr) participated in the study. The study included pre‐employment baseline data and three single day cross‐shift data collections. At each time point, bodyweight, a urine sample, and a point‐of‐care creatinine measure were collected from participants before and after work. Workers were not hired if they had an estimated glomerular filtration rate (eGFR) &lt; 60 ml□min‐1□1.73m‐2. To evaluate chronic hydration status, workers were divided into four groups (pre‐ to post‐shift body mass loss &lt; 1% at three, two, one, or zero of the time points). One‐way ANOVAs comparing change in WBCr and eGFR were completed to evaluate pre‐ to post‐season change for the different groups of workers based on hydration status. Statistical significance was set at α &lt; .05.RESULTSThere was a significant difference among worker group season change in eGFR ml□min‐1□1.73m‐2 (HC 2.05 ± 1.5, LC −5.47 ± 1.3, PW −0.30 ± 1.9, F‐score = 7.6, P = &lt;0.01) There was a significant difference in change of WBCr from pre‐season to post‐season between worker groups (HC −0.07 ± 0.19, LC 0.03 ± 0.27, PW −0.04 ± 0.15, F‐score = 7.72, P = &lt;0.01). Thirteen participants developed an eGFR &lt;90 ml□min‐1□1.73m‐2 and two participants developed an eGFR &lt;60 ml□min‐1□1.73m‐2 during the season. Self‐reported water consumptions during the work shift at the first time point was 17.6 ± 5.0 L for HC, 14.8 ± 2.5 L for LC, and 4.9 ± 1.4 L for PW. Among each work group, there was no significant difference in change in eGFR between workers who were hydrated at 3, 2, 1, or 0 time points (HC F‐score = 0.09, P = 0.92; LC F‐score = 1.44, P = 0.23; PW F‐score =1.07, P = 0.37).CONCLUSIONSChronic hydration status based on frequency of cross‐shift body mass &gt;1% did not relate to workers' risk of developing kidney damage over the course of a 6‐month sugarcane harvest. Only 13 and 2 participants developed an eGFR &lt;90 and &lt;60 ml□min‐1□1.73m‐2, respectively, possibly indicating that drinking large amounts of water and not hiring workers with a pre‐season eGFR &lt; 60 ml□min‐1□1.73m‐2 may help prevent the development of CKDu. However, there are likely other contributing factors such as work intensity and/or lifestyle.Support or Funding InformationInvestigation funded by Colorado School of Public Health and PantaleonThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

A Comparative Study of Byssinosis in Jute Industries.

Background:Byssinosis is an acute respiratory difficulty that is caused usually following exposure to cotton and hemp dust. Occurrence of such similar acute symptoms had been reported following exposure to jute dust/fiber also. With passage of time, Jute industries have modernized themselves for increased quality and productivity, which has lessened workforce and thereby provided more working space. However, occupational health benefit due to such changes has rarely been explored. This study was initiated to understand whether this modernization can protect the health of workers.Methodology:This study was carried out in two jute mills manufacturing jute clothes, jute bags, and so on. Interview of the workers for their occupational and morbidity details, medical examinations, as well as pre-shift and post-shift pulmonary function tests was carried out.Results:It was observed that chest tightness was significantly more in the industry with old technologies. Breathlessness was also more in this industry. As far as pulmonary function status is concerned, it was noted that greater than 5% cross-shift change in forced expiratory volume in one second was more common in the industry with old technology. Obstructive feature on lung function test was also observed in workers of both industries.Conclusion:The study concluded that exposure to jute dust has contributed to both acute and chronic respiratory health effects in the jute industry workers. Modernized industry showed lesser prevalence of acute symptoms and changes related to byssinosis. Modernization of processes in jute industries may prove fruitful in lowering the respiratory problems of workers.

Respiratory symptoms and lung function in relation to wood dust and monoterpene exposure in the wood pellet industry

Introduction: Wood pellets are used as a source of renewable energy for heating purposes. Common exposures are wood dust and monoterpenes, which are known to be hazardous for the airways. The purpose of this study was to study the effect of occupational exposure on respiratory health in wood pellet workers.Materials and methods: Thirty-nine men working with wood pellet production at six plants were investigated with a questionnaire, medical examination, allergy screening, spirometry, and nasal peak expiratory flow (nasal PEF). Exposure to wood dust and monoterpenes was measured.Results: The wood pellet workers reported a higher frequency of nasal symptoms, dry cough, and asthma medication compared to controls from the general population. There were no differences in nasal PEF between work and leisure time. A lower lung function than expected (vital capacity [VC], 95%; forced vital capacity in 1 second [FEV1], 96% of predicted) was noted, but no changes were noted during shifts. There was no correlation between lung function and years working in pellet production. Personal measurements of wood dust at work showed high concentrations (0.16–19 mg/m3), and exposure peaks when performing certain work tasks. Levels of monoterpenes were low (0.64–28 mg/m3). There was no association between exposure and acute lung function effects.Conclusions: In this study of wood pellet workers, high levels of wood dust were observed, and that may have influenced the airways negatively as the study group reported upper airway symptoms and dry cough more frequently than expected. The wood pellet workers had both a lower VC and FEV1 than expected. No cross-shift changes were found.

Heat stress, dehydration, and kidney function in sugarcane cutters in El Salvador – A cross-shift study of workers at risk of Mesoamerican nephropathy

BackgroundAn epidemic of progressive kidney failure afflicts sugarcane workers in Central America. Repeated high-intensity work in hot environments is a possible cause. ObjectivesTo assess heat stress, dehydration, biomarkers of renal function and their possible associations. A secondary aim was to evaluate the prevalence of pre-shift renal damage and possible causal factors. MethodsSugarcane cutters (N=189, aged 18–49 years, 168 of them male) from three regions in El Salvador were examined before and after shift. Cross-shift changes in markers of dehydration and renal function were examined and associations with temperature, work time, region, and fluid intake were assessed. Pre-shift glomerular filtration rate was estimated (eGFR) from serum creatinine. ResultsThe mean work-time was 4 (1.4–11) hours. Mean workday temperature was 34–36°C before noon, and 39–42°C at noon. The mean liquid intake during work was 0.8L per hour. There were statistically significant changes across shift. The mean urine specific gravity, urine osmolality and creatinine increased, and urinary pH decreased. Serum creatinine, uric acid and urea nitrogen increased, while chloride and potassium decreased. Pre-shift serum uric acid levels were remarkably high and pre-shift eGFR was reduced (<60mL/min) in 23 male workers (14%). ConclusionsThe high prevalence of reduced eGFR, and the cross-shift changes are consistent with recurrent dehydration from strenuous work in a hot and humid environment as an important causal factor. The pathophysiology may include decreased renal blood flow, high demands on tubular reabsorption, and increased levels of uric acid.

Cage Versus Noncage Laying-Hen Housings: Worker Respiratory Health

ABSTRACTThe objective of this study was to compare respiratory health of poultry workers in conventional cage, enriched cage and aviary layer housing on a single commercial facility, motivated by changing requirements for humane housing of hens. Three workers were randomly assigned daily, one to each of conventional cage, enriched cage, and aviary housing in a crossover repeated-measures design for three observation periods (for a total of 123 worker-days, eight different workers). Workers’ exposure to particles were assessed (Arteaga et al. J Agromedicine. 2015;20:this issue) and spirometry, exhaled nitric oxide, respiratory symptoms, and questionnaires were conducted pre- and post-shift. Personal exposures to particles and endotoxin were significantly higher in the aviary than the other housings (Arteaga et al., 2015). The use of respiratory protection was high; the median usage was 70% of the shift. Mixed-effects multivariate regression models of respiratory cross-shift changes were marginally significant, but the aviary system consistently posted the highest decrements for forced expiratory volume in 1 and 6 seconds (FEV1 and FEV6) compared with the enriched or conventional housing. The adjusted mean difference in FEV1 aviary − enriched cage housing was −47 mL/s, 95% confidence interval (CI): (−99 to 4.9), P = .07. Similarly, for FEV6, aviary − conventional housing adjusted mean difference was −52.9 mL/6 s, 95% CI: (−108 to 2.4), P = .06. Workers adopting greater than median use of respiratory protection were less likely to exhibit negative cross-shift pulmonary function changes. Although aviary housing exposed workers to significantly higher respiratory exposures, cross-shift pulmonary function changes did not differ significantly between houses. Higher levels of mask use were protective; poultry workers should wear respiratory protection as appropriate to avoid health decrements.

Cross-Shift Changes in Lung Function Among Palestinian Farmers During High- and Low-Exposure Periods to Pesticides: A Longitudinal Study

The purpose of this study was to study cross-shift changes of lung function in relation to pesticide use. One hundred and ninety-five male farmers, from a total of 250 farmers, performed lung function tests both pre- and post-shift during high- and low-pesticide-exposure periods. There were no associations between lung function differences across shifts and estimated quantity of pesticides used. However, the cross-shift reduction in forced expiratory volume in 1 second (FEV1; ΔFEV1) was more pronounced during the period when pesticides were used on a larger scale, September 2006, compared with the exposure period with a lower level of pesticide use, April 2007, +50 mL (95% confidence interval [CI]: +24, +76) and +17 mL (95% CI: −13, +48), respectively. This contrast was statistically significant only among the subset of never-smoking participants below 50 years of age. This finding suggests a possible obstructive effect of pesticide exposure on lung function among this rural male population in Palestine. A follow-up of farmers’ lung function in this part of the world along with high-quality measurements of exposure is needed.

Exposures and Cross-shift Lung Function Declines in Wildland Firefighters

Respiratory problems are common among wildland firefighters. However, there are few studies directly linking occupational exposures to respiratory effects in this population. Our objective was to characterize wildland fire fighting occupational exposures and assess their associations with cross-shift changes in lung function. We studied 17 members of the Alpine Interagency Hotshot Crew with environmental sampling and pulmonary function testing during a large wildfire. We characterized particles by examining size distribution and mass concentration, and conducting elemental and morphological analyses. We examined associations between cross-shift lung function change and various analytes, including levoglucosan, an indicator of wood smoke from burning biomass. The levoglucosan component of the wildfire aerosol showed a predominantly bimodal size distribution: a coarse particle mode with a mass median aerodynamic diameter about 12 μm and a fine particle mode with a mass median aerodynamic diameter < 0.5 μm. Levoglucosan was found mainly in the respirable fraction and its concentration was higher for fire line construction operations than for mop-up operations. Larger cross-shift declines in forced expiratory volume in one second were associated with exposure to higher concentrations of respirable levoglucosan (p < 0.05). Paired analyses of real-time personal air sampling measurements indicated that higher carbon monoxide (CO) concentrations were correlated with higher particulate concentrations when examined by mean values, but not by individual data points. However, low CO concentrations did not provide reliable assurance of concomitantly low particulate concentrations. We conclude that inhalation of fine smoke particles is associated with acute lung function decline in some wildland firefighters. Based on short-term findings, it appears important to address possible long-term respiratory health issues for wildland firefighters. [Supplementary materials are available for this article. Go to the publisher's online edition of Journal of Occupational and Environmental Hygiene for the following free supplemental resources: a file containing additional information on historical studies of wildland fire exposures, a file containing the daily-exposure-severity questionnaire completed by wildland firefighter participants at the end of each day, and a file containing additional details of the investigation of correlations between carbon monoxide concentrations and other measured exposure factors in the current study.]