Chronic exposure to emissions from photocopiers in copy shops causes oxidative stress and systematic inflammation among photocopier operators in India

Association between Red Blood Cell Distribution Width and In-Hospital Mortality among Congestive Heart Failure Patients with Diabetes among Patients in the Intensive Care Unit: A Retrospective Cohort Study

Background

Elevated red blood cell distribution width (RDW) levels are strongly associated with an increased risk of mortality in patients with congestive heart failure (CHF). Additionally, heart failure has been closely linked to diabetes. Nevertheless, the relationship between RDW and in-hospital mortality in the intensive care unit (ICU) among patients with both congestive heart failure (CHF) and diabetes mellitus (DM) remains uncertain.

Methods

This retrospective study utilized data from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database, a comprehensive critical care repository. RDW was assessed as both continuous and categorical variables. The primary outcome of the study was in-hospital mortality at the time of hospital discharge. We examined the association between RDW on ICU admission and in-hospital mortality using multivariable logistic regression models, restricted cubic spline analysis, and subgroup analysis.

Results

The cohort consisted of 7,063 patients with both DM and CHF (3,135 females and 3,928 males). After adjusting for potential confounders, we found an association between a 9% increase in mortality rate and a 1 g/L increase in RDW level (OR = 1.09; 95% CI, 1.05∼1.13), which was associated with 11 and 58% increases in mortality rates in Q2 (OR = 1.11, 95% CI: 0.87∼1.43) and Q3 (OR = 1.58, 95% CI: 1.22∼2.04), respectively, compared with that in Q1. Moreover, we observed a significant linear association between RDW and in-hospital mortality, along with strong stratified analyses to support the findings.

Conclusions

Our findings establish a positive association between RDW and in-hospital mortality in patients with DM and CHF.

The Impact of Fine Particulate Matter on Embryonic Development

Airborne fine particulate matter (PM2.5) in air pollution has become a significant global public health concern related to allergic diseases. Previous research indicates that PM2.5 not only affects the respiratory system but may also induce systemic inflammation in various tissues. Moreover, its impact may vary among different populations, with potential consequences during pregnancy and in newborns. However, the precise mechanisms through which PM2.5 induces inflammatory reactions remain unclear. This study aims to explore potential pathways of inflammatory responses induced by PM2.5 through animal models and zebrafish embryo experiments. In this study, zebrafish embryo experiments were conducted to analyze the effects of PM2.5 on embryo development and survival, and mouse experimental models were employed to assess the impact of PM2.5 stimulation on various aspects of mice. Wild-type zebrafish embryos were exposed to a PM2.5 environment of 25-400 μg/mL starting at 6 h after fertilization (6 hpf). At 6 days post-fertilization, the survival rates of the 25, 50, 100, and 200 µg/mL groups were 100%, 80, 40%, and 40%, respectively. Zebrafish embryos stimulated with 25 μg/mL of PM2.5 still exhibited successful development and hatching. Additionally, zebrafish subjected to doses of 25-200 μg/mL displayed abnormalities such as spinal curvature and internal swelling after hatching, indicating a significant impact of PM2.5 stimulation on embryo development. In the mouse model, mice exposed to PM2.5 exhibited apparent respiratory overreaction, infiltration of inflammatory cells into the lungs, elevated levels of inflammatory response-related cytokines, and inflammation in various organs, including the liver, lungs, and uterus. Blood tests on experimental mice revealed increased expression of inflammatory and chemotactic cytokines, and GSEA indicated the induction of various inflammatory responses and an upregulation of the TNF-α/NFκB pathway by PM2.5. Our results provide insights into the harmful effects of PM2.5 on embryos and organs. The induced inflammatory responses by PM2.5 may be mediated through the TNF-α/NFκB pathway, leading to systemic organ inflammation. However, whether PM2.5-induced inflammatory responses in various organs and abnormal embryo development are generated through different pathways requires further study to comprehensively clarify and identify potential treatment and prevention methods.

A case study on occupational exposure assessment and characterization of particles in a printing shop in China

Printers can release numerous particles to contaminate indoor environments and pose health risks. Clarifying the exposure level and physicochemical properties of printer-emitted particles (PEPs) will help to evaluate the health risks of printer operator. In our study, the particles concentration in the printing shop was monitored in real time for a long time (12 h/day, total 6 days), and the PEPs were collected to characterize their physicochemical properties including shape, size and compositions. The result showed that the concentration of PEPs is closely related to the printing workload and the highest particle mass concentration of PM₁₀ and PM_2.5 was 212.73 μg m^-3 and 91.48 μg m^-3, respectively. The concentration of PM₁ in the printing shop was in the range of 11.88-80.59 μg m^-3 for mass value, and 174.83-1348.84 P cm^-3 for count value which changed with the printing volume. The particle sizes of PEPs were less than 900 nm, 47.99% of PEPs was less than 200 nm, and 14.21% of the particles were at the nanoscale. PEPs contained 68.92% organic carbon (OC), 5.31% elemental carbon (EC), 3.17% metal elements, and 22.60% other inorganic additives, which contained more OC and metal elements than toners. Total polycyclic aromatic hydrocarbons (PAHs) levels were 18.95 ng/mg in toner and 120.70 ng/mg in PEPs. The carcinogenic risk of PAHs in PEPs was 1.40 × 10^-7. These findings suggested future studies should pay more attention to the health effects of printing workers exposed to nanoparticles.

Changes in heart rate variability of healthy subjects shortly exposed to printing shop particles and the effect of air purifier intervention

Particulate matter (PM) released by printers may cause airway inflammation and cardiac electrophysiological changes. We conducted a two-stage crossover study to examine the association between short-term exposure to printing shop particles (PSPs) and the heart rate variability (HRV) among healthy volunteers, as well as to evaluate the effect of air purifier intervention. The on-site assessments of PSPs and individual HRV parameters of the volunteers were used to analyze the influence of size-fractionated PSPs and air purifier intervention on HRV at different lag times after PSPs exposure (0 min, 5 min, 15 min, and 30 min) by using the linear mixed-effects models. We observed that changes in 6 HRV parameters were associated with particle mass concentration (PMC) of PSPs, and changes in 8 HRV parameters were associated with particle number concentration (PNC) of PSPs. The sensitive HRV parameters were the square root of the mean of the sum of the squares of differences between adjacent NN intervals (rMSSD), NN50 count divided by the total number of all NN intervals (pNN50), normalized high frequency power (nHF), very high frequency power (VHF), normalized low frequency power (nLF), and the ratio of low frequency power to high frequency power (LF/HF). Most HRV parameters exhibited the strongest effect associated with PMC and PNC at a lag time of 30 min. The air purifier intervention markedly reduced the PNC and PMC of size-fractionated PSPs, enhanced 5 HRV parameters, and decreased the nLF and LF/HF. Our study suggests that short-term exposure to PSPs can affect HRV parameters, reflecting changes in cardiac autonomic nervous activity, and the use of an air purifier can reduce the concentration of PSPs and improve the autonomic nervous system activity of the exposed individuals.

Biomarkers of oxidative stress in urine and plasma of operators at six Singapore printing centers and their association with several metrics of printer-emitted nanoparticle exposures

Inhalation of nanoparticles emitted from toner-based printing equipment (TPE), such as laser printers and photocopiers, also known as PEPs, has been associated with systemic inflammation, hypertension, cardiovascular disease, respiratory disorders, and genotoxicity. Global serum metabolomics analysis in 19 healthy TPE operators found 52 dysregulated biomolecules involved in upregulation of inflammation, immune, and antioxidant responses and downregulation of cellular energetics and cell proliferation. Here, we build on the metabolomics study by investigating the association of a panel of nine urinary OS biomarkers reflecting DNA/RNA damage (8OHdG, 8OHG, and 5OHMeU), protein/amino acid oxidation (o-tyrosine, 3-chlorotyrosine, and 3-nitrotyrosine), and lipid oxidation (8-isoprostane, 4-hydroxy nonenal, and malondialdehyde [MDA]), as well as plasma total MDA and total protein carbonyl (TPC), with several nanoparticle exposure metrics in the same 19 healthy TPE operators. Plasma total MDA, urinary 5OHMeU, 3-chlorotyrosine, and 3-nitrotyrosine were positively, whereas o-tyrosine inversely and statistically significantly associated with PEPs exposure in multivariate models, after adjusting for age and urinary creatinine. Urinary 8OHdG, 8OHG, 5OHMeU, and total MDA in urine and plasma had group mean values higher than expected in healthy controls without PEPs exposure and comparable to those of workers experiencing low to moderate levels of oxidative stress (OS). The highest exposure group had OS biomarker values, most notably 8OHdG, 8OHG, and total MDA, that compared to workers exposed to welding fumes and titanium dioxide. Particle number concentration was the most sensitive and robust exposure metric. A combination of nanoparticle number concentration and OS potential of fresh aerosols is recommended for larger scale future studies.

Unique attributes of obesity in India: A narrative review

Obesity has become a burgeoning epidemic in India, even though the country is still dealing with undernutrition. As a significant determinant of the Metabolic Syndrome (MetS) and non-communicable diseases (NCDs) such as type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD), understanding the Indian context of the problem and learning how to deal with the obesity epidemic in this country has gained paramount importance. This narrative review points to the unique features of the obesity epidemic in India and its associated contributing factors, including the evolving nature of the Indian diet, the peculiarity of the increased adiposity at lower BMIs, unique obesity-associated genetic variants in Indians, the contribution of the gut microbiome, the impact of chronic inflammation and the role of ambient air pollution, and the contribution of decreased physical activity levels concerning the rapid urbanisation and the built environment. We believe that disseminating our insights into these unique features influencing the development of obesity in India will help increase global awareness and pave the way for better control and management of this obesity epidemic.

Association of nanoparticle exposure with serum metabolic disorders of healthy adults in printing centers

Printers are everyday devices in both our homes and workplaces. We have previously found high occupational exposure levels to toner-based printer emitted nanoparticles (PEPs) at printing centers. To elucidate the potential health effects from exposure to PEPs, a total of 124 human serum samples were collected from 32 workers in the printing centers during the repeated follow-up measurements, and global serum metabolomics were analyzed in three ways: correlation between metabolic response and personal exposure (dose response exposure); metabolite response changes between Monday and Friday of a work week (short-term exposure), and metabolite response in relation to length of service in a center (long-term exposure). A total of 52 key metabolites changed significantly in relation to nanoparticle exposure levels. The primary dysregulated pathways included inflammation and immunity related arginine and tryptophan metabolism. Besides, some distinct metabolite expression patterns were found to occur during the transition from short-term to long-term exposures, suggesting cumulative effect of PEPs exposure. These findings, for the first time, highlight the inhalation exposure responses to printer emitted nanoparticles at the metabolite level, potentially serving as pre-requisites for whole organism and population responses, and are inline with emerging findings on potential health effects.

Elevated Urinary Biomarkers of Oxidative Damage in Photocopier Operators following Acute and Chronic Exposures

Inhalation exposures to nanoparticles (NPs) from printers and photocopiers have been associated with upper airway and systemic inflammation, increased blood pressure, and cases of autoimmune and respiratory disorders. In this study we investigate oxidative stress induced by exposures to copier-emitted nanoparticles using a panel of urinary oxidative stress (OS) biomarkers representing DNA damage (8-hydroxydeoxyguanosine, 8-OHdG; 8-hydroxyguanosine, 8-OHG; 5-hydroxymethyl uracil 5-OHMeU), lipid peroxidation (8-isoprostane; 4-hydroxynonenal, HNE), and protein oxidation biomarkers (o-tyrosine, 3-chlorotyrosine, and 3-nitrotyrosine) under conditions of acute (single 6 h exposure, 9 volunteers, 110 urine samples) and chronic exposures (6 workers, 11 controls, 81 urine samples). Urinary biomarkers were quantified with liquid chromatography–tandem mass spectrometry after solid phase extraction sample cleanup. 8-OHdG, 8-OHG, 8-isoprostane, and HNE were significantly elevated in both the acute and chronic exposure study participants relative to the controls. In the acute exposure study, the geometric mean ratios post-/pre-exposure were 1.42, 1.10, 2.0, and 2.25, respectively. Urinary 8-OHG and HNE increased with time to at least 36 h post-exposure (post-/pre-exposure GM ratios increased to 3.94 and 2.33, respectively), suggesting slower generation and/or urinary excretion kinetics for these biomarkers. In chronically exposed operators, the GM ratios of urinary biomarkers relative to controls ranged from 1.52 to 2.94, depending on the biomarker. O-Tyrosine and 5-OHMeU biomarkers were not significantly different from the controls. 3-chlorotyrosine and 3-nitrotyrosine were not detected in the urine samples. We conclude that NPs from photocopiers induce systemic oxidative stress by damaging DNA, RNA, and lipids. Urinary levels of 8-OHdG, 8-OHG, HNE, and 8-isoprostane were orders of magnitude higher than in nanocomposite processing workers, comparable to nano titanium dioxide and fiberglass manufacturing workers, but much lower than in shipyard welding and carbon nanotube synthesis workers. Biomarkers 8-OHdG, 8-OHG, 8-isoprostane, and HNE appear to be more sensitive and robust urinary biomarkers for monitoring oxidative stress to NPs from photocopiers.

A Case Study on the Assessment of Chemical and Physical Pollution Levels during the Copying Process

In accordance with sustainable development goals (SDG’s), urgent action should be taken to make the societal and natural environments better for human beings. People spend most of their time indoors, therefore growing attention is devoted to address indoor air pollution. When the sources of anthropogenic indoor air pollution (copiers, laser printers) are operated indoors, then chemical and physical indoor air pollution may be higher than air pollution outdoors. Ozone, aerosol particles and volatile organic compounds are the result of pollution caused by copiers and printers. The research was carried out in a copying room by recording chemical (ozone and aerosol particles) and physical (noise) environmental pollution. To determine instantaneous ozone concentrations in the copying room, an ozone analyzer O3 41M was used, while to evaluate the effect of ozone on the ambient air of the copying room, passive samplers were used. To determine the number and concentration of aerosol particles in the ambient air of the office, a particle counter AZ-5 was used. In addition, a DrDAQ data logger was used to measure noise emitted by the copier and ambient temperature as well as relative air humidity. It was found that the distribution of ozone and aerosol particles in the copying room was mostly determined by the copying intensity. The maximum concentration of ozone and aerosol particles was determined during automatic copying (91–120 copies/min).

Local and systemic influence of toxic levels of airborne ozone on the inflammatory response in rats

Introduction

Ozone is not harmful itself; however, it directly oxidises biomolecules and produces radical-dependent cytotoxicity. Exposure to ozone is by inhalation and therefore the lungs develop the main anti-inflammatory response, while ozone has an indirect impact on the other organs. This study investigated the local and systemic effects of the ozone-associated inflammatory response.

Material and Methods

Three groups each of 5 Wistar Han rats aged 6 months were exposed for 2h to airborne ozone at 0.5 ppm and a fourth identical group were unexposed controls. Sacrifice was at 3h after exposure for control rats and one experimental group and at 24 h and 48 h for the others. Lung and liver samples were evaluated for changes in expression of transforming growth factor beta 1, anti-inflammatory interleukin 10, pro-inflammatory tumour necrosis factor alpha and interleukin 1 beta and two nuclear factor kappa-light-chain-enhancer of B cells subunit genes. Total RNA was isolated from the samples in spin columns and cDNA was synthesised in an RT-PCR. Expression levels were compared to those of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and analysed statistically.

Results

All variables changed non-linearly over time comparing experimental groups to the control. Conspicuous expression changes in the subunit genes and cytokines were observed in both evaluated organs.

Conclusion

Locally and systemically, inflammation responses to ozone inhalation include regulation of certain genes’ expression. The mechanisms are unalike in lungs and liver but ozone exerts a similar effect in both organs. A broader range of variables influential on ozone response should be studied in the future.

Increased intestinal permeability with elevated peripheral blood endotoxin and inflammatory indices for e-waste lead exposure in children

Lead (Pb) entering the body through different channels can damage the function of intestinal mucosal barrier and cause the body stressful inflammatory response to enhance. This study conducted a cross-sectional study to investigate the effects of Pb exposure on intestinal permeability in children by measuring the level of bacterial endotoxin and index of inflammatory cell types in peripheral blood. From November to December 2018, we recruited 187 participants aged 3-6 years by stratified randomization, from an electronic-waste-exposed group (n = 82) and a referent group (n = 105). General demographic information, past history of the digestive system in child, and family situation were informed by children's guardians with questionnaires. Children in the exposed group showed lower weight, height, and body mass index while more diarrhea in a month. Blood Pb and plasma endotoxin were elevated in exposed children than referent children and the positive relationship between them was shown in all children [B (95% CI): 0.072 (0.008, 0.137), P = 0.033]. Peripheral monocyte counts and leukotriene B₄ (LTB₄) levels were significantly increased in the exposed group. Endotoxin levels were positively correlated with neutrophils, monocytes, and LTB₄ [B (95% CI): 0.054 (0.015, 0.093), 0.018 (0.005, 0.031), and 0.049 (0.011, 0.087), respectively, P < 0.05]. To sum up, the exposed children showed lower physical growth levels, poorer gut health, and increased intestinal permeability, which was related to high blood Pb and peripheral inflammatory indices. These results suggest the possible adverse impact of environmental Pb exposure on the intestinal health of children.

Chronic upper airway and systemic inflammation from copier emitted particles in healthy operators at six Singaporean workplaces

Toner-based printing equipment (TPE), including laser printers and photocopiers, utilize several engineered nanomaterials (ENMs) to improve toner performance. Operation of TPE, which rarely employ any exposure controls, generates high exposures to nanoparticles that contain ENMs and complex organics. Epidemiological literature in copier operators documents respiratory effects, including nasal blockage, cough, excessive sputum, and breathing difficulties, cardiovascular effects, oxidative stress, and inflammation. However, epidemiological studies in humans with adequate exposure assessment and dose-response analysis are lacking. We present herein the analysis of the upper airway and systemic inflammation in plasma of 19 healthy copier operators at six Singapore workplaces. We employed a repeated panel design (four biomarker measurements over two weeks) combined with a multi-marker approach (14 inflammatory cytokines in plasma and nasal lavage (NL)), and comprehensive exposure assessment using four distinct exposure metrics. We investigated spatial and temporal patterns of markers of upper airway and systemic inflammation and their association with various exposure metrics. Several inflammatory markers, namely fractalkine, IL-1β, and IL-1α in NL, and fractalkine, IL-1β, TNF-α, and IFN-γ in plasma, were strongly and positively associated with at least one exposure metric, whereas GM-CSF was negatively associated. The inflammation score was also strongly associated with TPE nanoparticle exposures. Exposure to TPE emissions induced moderate upper airway inflammation and stronger systemic inflammation in these healthy operators, characterized by upregulation of at least IL-1β, fractalkine, TNF-α and IFN-γ. Proinflammatory cytokines TNF-α, IFN-γ and IL-1β play an important role in orchestrating inflammatory responses in various clinical conditions, including cardiovascular and autoimmune disease, and likely trigger activation of endothelial cells, leading to overexpression of fractalkine, a chemokine that is involved in and associated with multiple disorders, including atherosclerosis and vascular disease. Future larger-scale epidemiological studies in these workers and consumers exposed chronically to TPE nanoparticle emissions and proactive interventions to reduce or eliminate TPE exposures are recommended.

Health effects of occupational exposure to printer emissions on workers in China: Cardiopulmonary function change

Printers emitted nanoparticles (NPs), ozone (O₃) and volatile organic chemicals (VOCs) during operation that elicited adverse effects on indoor air quality of the printing room, which may affect the health of exposed workers. The aim of this work was to explore the health effects of occupational exposure to printer emissions on workers, especially cardiovascular and lung function. We sampled particles in the print shop for characterization, including particle size distribution and elemental composition, and measured PM₁ number concentrations in print shops and other workplaces. We assessed blood pressure, heart rate and pulmonary function in 53 printing room workers and 54 controls in Beijing, China. Multiple linear regression analysis were used to examine health effects of exposure to printer emissions. The PM₁ number concentration in the print shop was more than 2 times that of the control group. Compared with controls, the exposed workers with lower education and income had heavier workload with a median of 7 days per week and 12 h per day on working days, and presented cardiopulmonary function injury with increased the diastolic blood pressure (DBP), systolic blood pressure (SBP), and mean arterial pressure (MAP). The most significant changes of cardiopulmonary function were found in exposed workers with more than 10 years of working age. Multiple linear regression also showed printer emissions exposure was associated with increased SBP and MAP, while decreased lung function indices. This study found changes in the cardiopulmonary function of staff members exposed to printer emissions, which prompted the necessity and urgency of improving the environment of printing rooms and protecting the health of exposed workers.

Ambient PM2.5 exposures and systemic biomarkers of lipid peroxidation and total antioxidant capacity in early pregnancy

Evidence for effects of PM_2.5 on systemic oxidative stress in pregnant women is limited, especially in early pregnancy. To estimate the associations between ambient PM_2.5 exposures and biomarkers of lipid peroxidation and total antioxidant capacity (T-AOC) in women with normal early pregnancy (NEP) and women with clinically recognized early pregnancy loss (CREPL), 206 early pregnant women who had measurements of serum malondialdehyde (MDA) and T-AOC were recruited from a larger case-control study in Tianjin, China from December 2017 to July 2018. Ambient PM_2.5 concentrations of eight single-day lags exposure time windows before blood collection at the women's residential addresses were estimated using temporally-adjusted land use regression models. Effects of PM_2.5 exposures on percentage change in the biomarkers were estimated using multivariable linear regression models adjusted for month, temperature, relative humidity, gestational age and other covariates. Unconstrained distributed lag models were used to estimate net cumulative effects. Increased serum MDA and T-AOC were significantly associated with increases in PM_2.5 at several lag exposure time windows in both groups. The net effects of each interquartile range increase in PM_2.5 over the preceding 8 days on MDA were significantly higher (p < 0.001) in CREPL [52% (95% CI: 41%, 62%)] than NEP [22% (95% CI: 9%, 36%)] women. Net effects of each interquartile range increase in PM_2.5 over the preceding 5 days on T-AOC were significantly lower (p = 0.010) in CREPL [14% (95% CI: 9%, 19%)] than NEP [24% (95% CI: 18%, 29%)] women. Exposure to ambient PM_2.5 may induce systemic lipid peroxidation and antioxidant response in early pregnant women. More severe lipid peroxidation and insufficient antioxidant capacity associated with PM_2.5 was found in CREPL women than NEP women. Future studies should focus on mechanisms of individual susceptibility and interventions to reduce PM_2.5-related oxidative stress in the first trimester.

Estimation of indoor air pollutant during photocopy/printing operation: a computational fluid dynamics (CFD)-based study

Population form a homeostat with environment where they live and exchange continuous gas for their respiration, which is the primary pathway for the pollutants to enter into human metabolism. The pollution present indoor is due to multiple sources like electronic and electrical equipment, clothes, furniture and other anthropogenic activity. The concentration of these pollutants changes with time and depends mainly on source type (continuous/intermittent), time of the operation and release/ventilation/wind velocity/pollutant dispersion and anthropogenic activity. It has been observed that equipment like printers, printing machines, photocopiers, etc., releases several pollutants like volatile organic compounds (VOCs), ozone (O₃), semi-volatile organic compounds, benzene (C₆H₆), toluene and suspended particulate matter during operation. This work represents the emissions of VOCs, benzene, and toluene during photocopy. The numerical validation of results was done using Fluent, which is an application-based software which helps in physical modeling describing air flow and effect of multiple parameter on it like temperature and no of printing/photocopy (in proposed experiment) with respect to time. It has been observed from the results that the emissions of VOCs, benzene, and toluene increase from 0.09 to 1.13 PPM, 0.17 to 1.87 PPM and 30 to 235 PPM, respectively, as the operating duration, temperature (35-40 °C) and rate of printing/photocopying increase (120-200/h), and it is because printer/photocopy machine uses heat and pressure to fix an image on the paper surface which subsequently result in higher emission. Multiple adverse health, safety and environmental impacts due to operation of photocopy/printing call for in-depth study, guidance, and monitoring of the workers occupationally associated with this operation for their well-being.

Effects of toner-handling work on respiratory function, chest X-ray findings, and biomarkers of inflammation, allergy, and oxidative stress: a 10-year prospective Japanese cohort study

Background

Exposure to toner, a substance used in photocopiers and printers, has been associated with siderosilicosis and other adverse effects. However, these findings are limited, and there is insufficient evidence on the long-term effects of toner exposure. Using longitudinal analysis, this study aimed to examine the effects of work involving toner exposure on the respiratory system over time.

Methods

We conducted a prospective cohort study in a Japanese toner and copier manufacturing enterprise between 2003 and 2013. The cohort included a total of 1468 workers, which comprised 887 toner-handling workers and 581 non-toner-handling workers. We subdivided the toner-handling workers into two groups according to the toner exposure concentration, based on the baseline survey in 2003. We compared the chest X-ray results, respiratory function indicators, and serum and urinary biomarkers of inflammation, allergy, and oxidative stress among the three groups: high-concentration toner exposure group, low-concentration toner exposure group, and non-toner-handling group. To consider the effects of individual differences on the longitudinal data, we used a linear mixed model.

Results

Similar chest X-ray results, the biomarkers, and most of the respiratory function indicators were found in the non-toner-handling and toner-handling groups. There were no significant yearly changes in the percentage of vital capacity (%VC) in the high-concentration toner exposure group, while there was a significant yearly increase in %VC in the low-concentration toner exposure group and non-toner-handling group. The yearly change in each group was as follows: high-concentration toner exposure group, − 0.11% (95% confidence interval [CI], − 0.29 to 0.08; P = 0.250); low-concentration toner exposure group, 0.13% (95% CI, 0.09–0.17; P < 0.001); and non-toner-handling group, 0.15% (95% CI, 0.01–0.20; P < 0.001).

Conclusions

In our 10-year prospective study, toner-handling work was not associated with the deterioration of respiratory function and an increase in biomarker values for inflammation, allergy, and oxidative stress. This finding suggests that toner-handling work is irrelevant to the onset of respiratory disease and has minimal adverse effects on the respiratory system under a well-managed work environment.

Supplementary Information

Supplementary information accompanies this paper at10.1186/s12890-020-01320-6.

Benzene-associated immunosuppression and chronic inflammation in humans: a systematic review

OBJECTIVE

Recent evidence has accumulated that the immune system is intimately intertwined with cancer development. Two key characteristics of carcinogens in which the immune system plays a central role are chronic inflammation and immunosuppression. In this systematic review, we investigated the association of chronic inflammatory and immunosuppressive outcomes with benzene, a widely used industrial chemical. Benzene has been confirmed to cause acute myeloid leukaemia and suspected to cause non-Hodgkin lymphoma, two cancers of the blood-forming system that affect immune cells.

METHODS

We systematically searched PubMed and Embase for all relevant studies using a combination of Medical Subject Headings (MeSH) and selected key words. The detailed review protocol, including search strategy, was registered with PROSPERO, the international prospective register of systematic reviews (#CRD42019138611).

RESULTS

Based on all human studies selected in the final review, we report new evidence of a benzene-induced immunosuppressive effect on the adaptive immune system and activation of the innate immune system to cause inflammation. In particular, benzene significantly lowers the number of white blood cells, particularly lymphocytes such as CD4+ T-cells, B-cells and natural killer cells, and increases proinflammatory biomarkers at low levels of exposure.

CONCLUSION

To the best of our knowledge, this is the first comprehensive review of benzene's immunotoxicity in humans. Based on results obtained from this review, we propose two potential immunotoxic mechanisms of how benzene induces leukaemia/lymphoma: (1) cancer invasion caused by proinflammatory cytokine production, and (2) cancer promotion via impaired immunosurveillance. Further studies will be required to confirm the connection between benzene exposure and its effects on the immune system.

Biomonitoring of DNA Damage in Photocopiers' Workers From Peshawar, Khyber Pakhtunkhwa, Pakistan

OBJECTIVES

The study was performed to know about the extent of occupational DNA damage in photocopiers' workers.

METHODS

Blood samples were collected from 136 exposed group and 74 control group. Comet assay was performed to assess the DNA damage caused by emissions from photocopiers.

RESULTS

The results indicated that there was a significant increase (P < 0.05) in DNA damage in persons working in photocopiers (122.1 ± 60.7) than the controls (56.6 ± 17.2). Duration of occupational exposure had positive correlation (r = 0.793, P < 0.001) with DNA damage. Age had significant effects on the total comet score (TCS) of the exposed group as compared to the control group (P < 0.05).

CONCLUSIONS

In conclusion, these findings indicate significant genotoxicity in photocopiers' workers.

Pilot deep RNA sequencing of worker blood samples from Singapore printing industry for occupational risk assessment

Several engineered nanomaterials (ENMs) are used in toner-based printing equipment (TPE) including laser printers and photocopiers to improve toner performance. High concentration of airborne nanoparticles due to TPE emissions has been documented in copy centers and chamber studies. Recent animal inhalation studies by our group suggested exposure to laser printer-emitted nanoparticles (PEPs) increased cardiovascular risk by impairing ventricular performance and inducing hypertension and arrhythmia, consistent with global transcriptomic and metabolomic profiling results. There has been no genome-wide transcriptomic analysis of workers exposed to TPE emissions to systematically assess the occupational exposure health risks. In this pilot study, deep RNA sequencing of blood samples of workers in two printing companies in Singapore was performed. The genome-scale analysis of the blood samples from TPE exposed workers revealed perturbed transcriptional activities related to inflammatory and immune responses, metabolism, cardiovascular impairment, neurological diseases, oxidative stress, physical morphogenesis/deformation, and cancer, when compared with the control peers (office workers). Many of these disease risks associated with particle inhalation exposures in such work environments were consistent with the observation from the PEPs rat inhalation studies. In particular, the cell adhesion molecules (CAMs) was a top significantly perturbed pathway in blood samples from exposed workers compared with the office workers in both companies. The protein expression of sICAM was verified in plasma of exposed workers, showing a positive correlation with daily average nanoparticle concentration in indoor air measured in these two companies. Larger scale genomic and molecular epidemiology studies in copier operators are warranted in order to assess potential risks from such particulate matter exposures.

Review of the characteristics and possible health effects of particles emitted from laser printing devices

Many studies have shown that the use of laser printing devices (LPDs) contributes to the release of particles into the indoor environment. However, after more than two decades of research, the physicochemical properties of LPD-emitted particles and the possible health effects from exposure to particles are still heavily debated. We therefore carried out a critical review of the published studies around emissions and health effects of LPD-emitted particles, aiming at elucidating the nature of these particles and their potential health risks. Realizing the varying methodologies of the studies, a classification of the reviewed studies is adopted, resulting in three categories of emission studies (chamber experiment, office/room measurement, and photocopy shop measurement), and three types of health studies (in vitro/animal studies, human studies in the real world, and human studies in controlled settings). The strengths and limitations of each type of study are discussed in-depth, which in turn helps to understand the cause of divergent results. Overall, LPD-emitted particles are mainly condensed or secondary-formed semi-volatile organic compounds (SVOCs), while solid toner particles account for a very small fraction. The health risk from exposure to LPD-emitted particles is small compared with the health risk from exposure to ambient particles.

Integrated Transcriptomics, Metabolomics, and Lipidomics Profiling in Rat Lung, Blood, and Serum for Assessment of Laser Printer-Emitted Nanoparticle Inhalation Exposure-Induced Disease Risks

Laser printer-emitted nanoparticles (PEPs) generated from toners during printing represent one of the most common types of life cycle released particulate matter from nano-enabled products. Toxicological assessment of PEPs is therefore important for occupational and consumer health protection. Our group recently reported exposure to PEPs induces adverse cardiovascular responses including hypertension and arrythmia via monitoring left ventricular pressure and electrocardiogram in rats. This study employed genome-wide mRNA and miRNA profiling in rat lung and blood integrated with metabolomics and lipidomics profiling in rat serum to identify biomarkers for assessing PEPs-induced disease risks. Whole-body inhalation of PEPs perturbed transcriptional activities associated with cardiovascular dysfunction, metabolic syndrome, and neural disorders at every observed time point in both rat lung and blood during the 21 days of exposure. Furthermore, the systematic analysis revealed PEPs-induced transcriptomic changes linking to other disease risks in rats, including diabetes, congenital defects, auto-recessive disorders, physical deformation, and carcinogenesis. The results were also confirmed with global metabolomics profiling in rat serum. Among the validated metabolites and lipids, linoleic acid, arachidonic acid, docosahexanoic acid, and histidine showed significant variation in PEPs-exposed rat serum. Overall, the identified PEPs-induced dysregulated genes, molecular pathways and functions, and miRNA-mediated transcriptional activities provide important insights into the disease mechanisms. The discovered important mRNAs, miRNAs, lipids and metabolites may serve as candidate biomarkers for future occupational and medical surveillance studies. To the best of our knowledge, this is the first study systematically integrating in vivo, transcriptomics, metabolomics, and lipidomics to assess PEPs inhalation exposure-induced disease risks using a rat model.

A Cohort Study on Respiratory Symptoms and Diseases Caused by Toner-Handling Work: Longitudinal Analyses from 2003 to 2013

The purpose of this study was to examine the effects of toner-handling work on respiratory symptoms and diseases. We conducted a prospective cohort study of 1468 workers between 2003 and 2013. The cohort included 887 toner-handling workers and 581 non-toner-handling workers, employed in one toner and copier manufacturing enterprise. Toner-handling workers were subdivided into two groups based on the 8-h time-weighted average toner exposure concentration for each work category in the baseline survey. We compared the incidence of respiratory disease and longitudinal changes in the prevalence of subjective respiratory symptoms among three groups, as follows: High-concentration toner exposure group, the low-concentration toner exposure group, and a control group. The incidence of respiratory disease and changes in the prevalence of subjective respiratory symptoms were not significantly different between the non-toner-handling group and the toner-handling group. In contrast, the odds ratio for yearly changes in the prevalence of wheezing without asthmatic response was significantly lower in the high-concentration toner exposure group than in the control group. At the study site, dust scattering was well controlled and workers used respiratory protection appropriately. These findings suggest that toner-handling work had little adverse effect on respiratory function in a work environment with sufficiently controlled ventilation.

Comprehensive Assessment of Short-Lived ROS and H2O2 in Laser Printer Emissions: Assessing the Relative Contribution of Metal Oxides and Organic Constituents

Inhalation exposure to nanoparticles from toner-based laser printer and photocopier emissions (LPEs) induces airway inflammation and systemic oxidative stress, cytotoxicity, and genotoxicity (such as DNA damage). Recent evidence from human and in vitro studies suggests a strong role for oxidative stress caused by free radicals, such as reactive oxygen species (ROS), in the toxicity of laser printer emissions. However, the amount of ROS generated from laser printer nanoparticle emissions and the relative contribution of various fractions (vapors, organics, metals, and metal oxides) have not been investigated to-date. In this study, we aim to quantify short-lived ROS and H₂O₂ laser printer emissions, as well as the relative contribution of various fractions of LPEs in ROS generation. An aerosol chamber with HEPA filtered air was used to generate LPE emissions from one representative printer. In separate experiments, size fractionated LPEs were collected on filters (particles) or impingers (particles and vapors). The nanoscale fraction of LPEs (PM_0.1) was further separated into the organic fraction and inorganic (transition metals/metal oxides) following a sequence of extraction with solvents and centrifugation. The short-lived ROS and H₂O₂ generated from each fraction were quantified with an acellular Trolox-based liquid chromatography-electrospray-tandem mass spectrometry (LC-ESI-MS/MS) method recently developed in our lab. The particulate fraction of LPEs PM_0.1 generated 2.68 times more total ROS (sum of short-lived ROS and H₂O₂) than the vapor fraction. In tested LPEs, transition metal oxides, which constituted 3% by mass, produced 69× and 202× times more short-lived ROS and H₂O₂, respectively, on a mass basis, than the organic fraction. Furthermore, fresh PM_0.1 generated 282× and 32× times more short-lived ROS and H₂O₂, respectively, than aged and processed PM_0.1. We conclude that transition metal oxides, albeit a minor constituent of the LPE PM_0.1 emissions, are the species responsible for the majority of acellular ROS in this printer. A larger range of printers should be tested in the future. Because transition metal oxides in toners originate primarily from engineering nanomaterials (ENMs) in printer toner powder, reformulation of toner powders to contain less of these ROS active metals is recommended.

Three Day Environmental Exposure May Trigger Oxidative Stress Development and Provoke Adaptive Response Resulting in Altered Antioxidant Activity

BACKGROUND

We aimed to investigate the polluted working environment triggers oxidative stress and alter enzymatic antioxidant activity by a short-term interval.

METHODS

The experimental study, performed in 2014, involved 94 workers from the Velenje Coalmine in Slovenia, arranged into three groups according to a number of consecutive working days in a mineshaft, supported by a control group. Levels of the antioxidant enzymes (GPx, CAT, SOD) together with TAC (the combined effect of all antioxidants) and 8-isoprostane (a biological marker of oxidative stress/damage) were measured in human plasma.

RESULTS

Workers occupationally exposed for three consecutive working days had significantly increased 8-isoprostane biomarker, a parameter of oxidative stress (P<0.001). The antioxidant levels of TAC (P<0.001), CAT (P<0.001) and SOD (P<0.001) were all significantly decreased compared to a control group.

CONCLUSION

Workers in polluted working environment had significantly increased oxidative stress and altered antioxidant activity already on a third consecutive working day.

Assessment of environmental and ergonomic hazard associated to printing and photocopying: a review

"Knowledge is power" and distribution of knowledge is fueled by printing and photocopying industry. Even as printing and photocopying industry have revolutionized the availability of documents and perceptible image quickly at extremely inexpensive and affordable cost, the boon of its revolution has turned into a bane by irresponsible, uncontrolled and extensive use, causing irreversible degradation to not only ecosystem by continuous release of ozone and other volatile organic compounds (VOCs) but also the health of workers occupationally exposed to it. Indoor ozone level due to emission from different photocopying equipment's increases drastically and the condition of other air quality parameters are not different. This situation is particularly sedate in extremely sensitive educational and research industry where sharing of knowledge is extremely important to meet the demands. This work is an attempt to catalogue all the environmental as well as health impacts of printing or photocopying. It has been observed that printing/photocopying operation is a significant factor contributing to indoor air quality degradation, which includes increase in concentration of ozone, VOCs, semi-volatile organic compounds (SVOCs) and heavy metals such as cadmium, selenium, arsenic, zinc, nickel, and other pollutants from photocopy machines. The outcome of this study will empower the manufactures with information regarding ozone and other significant emission, so that their impact can be reduced.

Health risk assessment due to biomass smoke exposure in Indian indoor environment: An empirical approach using lung deposition model

The paper subsumes a framework that assesses health risk due to exposure to different fuel combustion through articulation of modern microscopic techniques, empirical equations, lung diagnostic tools and a pre-existing model that has been extrapolated to futuristic aspects (within controlled conditions). The framework was tested on 132 household cooks belonging to different age groups and using different types of fuel. The inhalable fraction released during fuel combustion varied in morphological characteristics and deposition site. Micrographs obtained using Scanning Electron Microscope (SEM) analysis of (biomass smoke) soot indicates aggregate formation attributing to a higher level of health risk. Further, abnormal ventilatory function along with higher risk (RR > 1) was more evident within biomass fuel users. The condition further exacerbates while using dung cakes due to high levels of emissions (294.3 particles/liter) that deposit in the upper respiratory tract (0.0899). Further, the population attributable risk percent (79%) calculated on the basis of cooking behavior suggests a 'rural culture' health determinant as clean fuel usage is not practiced as an outcome of low literacy and poor income in the region. These preliminary findings highlight the drudgery of impuissant women who are exposed to high particulate emissions on a regular basis which results in reduced lung function. Nevertheless, further cogitation is required to eliminate the limitations in this study and explore further linkages between exposure and vulnerable group to generate meaningful policy recommendations.

Assessing the chronic respiratory health risk associated with inhalation exposure to powdered toner for printing in actual working conditions: a cohort study on occupationally exposed workers over 10 years

BACKGROUND

Little epidemiological evidence exists regarding the chronic respiratory effects of inhaled powdered toner exposure in humans, although several case reports have suggested the existence of lung disorders that might be related to exposure to toner dust.

OBJECTIVE

We aimed to estimate the chronic health risk to humans associated with routine toner dust exposure in copier industry workers under current actual work conditions.

DESIGN

A prospective observational cohort study of occupational population.

METHODS

Changes in chest radiogram, spirometry measurements and serum and urine biomarkers of biomedical responses to extrinsic stress, as well as subjective symptoms were longitudinally observed for up to 10 years in Japanese copier industry workers responsible for the manufacturing, maintenance or recycling of powdered toner or toner-using machines. A total of 694 subjects who did not change their work category during the follow-up and were free from chronic respiratory diseases at the baseline survey provided reliable results on at least three survey occasions during 3 years or more of follow-up.

RESULTS

Typical fibrosis findings associated with pneumoconiosis was not observed on chest radiograms. No significant differences associated with toner exposure were noted in the frequency of new incidence of either non-specific findings on chest radiogram or serum fibrosis biomarkers (sialylated carbohydrate antigen KL-6 and surfactant protein D). However, the exposed subjects tended to show increases in the frequency of respiratory symptoms and reduced spirometry results during the follow-up compared with the control group, although significant differences were only seen in chronic cough.

CONCLUSIONS

Under the current reasonably controlled work environmental conditions, lung fibrotic changes caused by inhaled dust exposure, including powdered toner, appear to be relatively uncommon; however, non-specific temporal irritation causing subjective symptoms and inflammatory responses might exist.

Synergistic effects of engineered nanoparticles and organics released from laser printers using nano-enabled toners: potential health implications from exposures to the emitted organic aerosol

Recent studies have shown that engineered nanoparticles (ENPs) are incorporated into toner powder used in printing equipment and released during their use. Thus, understanding the functional and structural composition and potential synergistic effects of this complex aerosol and released gaseous co-pollutants is critical in assessing their potential toxicological implications and risks. In this study, toner powder and PEPs were thoroughly examined for functional and molecular composition of the organic fraction and the concentration profile of 16 Environmental Protection Agency (EPA)-priority polycyclic aromatic hydrocarbons (PAH) using state of the art analytical methods. Results show significant differences in abundance of non-exchangeable organic hydrogen of toner powder and PEPs, with a stronger aromatic spectral signature in PEPs. Changes in structural composition of PEPs are indicative of radical additions and free-radical polymerization favored by catalytic reactions, resulting in formation of functionalized organic species. Particularly, accumulation of aromatic carbons with strong styrene-like molecular signatures on PEPs is associated with formation of semivolatile heavier aromatic species (i.e., PAHs). Further, the transformation of low molecular weight PAHs in the toner powder to high molecular weight PAHs in PEPs was documented and quantified. This may be a result of synergistic effects from catalytic metal/metal oxide ENPs incorporated into the toner and the presence/release of semi-volatile organic species (SVOCs). The presence of known carcinogenic PAHs on PEPs raises public health concerns and warrants further toxicological assessment.

Health effects of laser printer emissions: a controlled exposure study

Ultrafine particles emitted from laser printers are suspected to elicit adverse health effects. We performed 75-minute exposures to emissions of laser printing devices (LPDs) in a standardized, randomized, cross-over manner in 23 healthy subjects, 14 mild, stable asthmatics, and 15 persons reporting symptoms associated with LPD emissions. Low-level exposures (LLE) ranged at the particle background (3000 cm^-3 ) and high-level exposures (HLE) at 100 000 cm^-3 . Examinations before and after exposures included spirometry, body plethysmography, transfer factors for CO and NO (TLCO, TLNO), bronchial and alveolar NO, cytokines in serum and nasal secretions (IL-1β, IL-5, IL-6, IL-8, GM-CSF, IFNγ, TNFα), serum ECP, and IgE. Across all participants, no statistically significant changes occurred for lung mechanics and NO. There was a decrease in volume-related TLNO that was more pronounced in HLE, but the difference to LLE was not significant. ECP and IgE increased in the same way after exposures. Nasal IL-6 showed a higher increase after LLE. There was no coherent pattern regarding the responses in the participant subgroups or single sets of variables. In conclusion, the experimental acute responses to short but very high-level LPD exposures were small and did not indicate clinically relevant effects compared to low particle number concentrations.

Nanoparticle exposures from nano-enabled toner-based printing equipment and human health: state of science and future research needs

Toner formulations used by laser printers (LP) and photocopiers (PC), collectively called "toner-based printing equipment" (TPE), are nano-enabled products (NEP) because they contain several engineered nanomaterials (ENM) that improve toner performance. It has been shown that during consumer use (printing), these ENM are released in the air, together with other semi-volatile organic nanoparticles, and newly formed gaseous co-pollutants such as volatile organic compounds (VOC). The aim of this review is to detail and analyze physico-chemical and morphological (PCM), as well as the toxicological properties of particulate matter (PM) emissions from TPE. The review covers evolution of science since the early 2000, when this printing technology first became a subject of public interest, as well as the lagging regulatory framework around it. Important studies that have significantly changed our understanding of these exposures are also highlighted. The review continues with a critical appraisal of the most up-to-date cellular, animal and human toxicological evidence on the potential adverse human health effects of PM emitted from TPE. We highlight several limitations of existing studies, including (i) use of high and often unrealistic doses in vitro or in vivo; (ii) unrealistically high-dose rates in intratracheal instillation studies; (iii) improper use of toners as surrogate for emitted nanoparticles; (iv) lack of or inadequate PCM characterization of exposures; and (v) lack of dosimetry considerations in in vitro studies. Presently, there is compelling evidence that the PM_0.1 from TPE are biologically active and capable of inducing oxidative stress in vitro and in vivo, respiratory tract inflammation in vivo (in rats) and in humans, several endpoints of cellular injury in monocultures and co-cultures, including moderate epigenetic modifications in vitro. In humans, limited epidemiological studies report typically 2-3 times higher prevalence of chronic cough, wheezing, nasal blockage, excessive sputum production, breathing difficulties, and shortness of breath, in copier operators relative to controls. Such symptoms can be exacerbated during chronic exposures, and in individuals susceptible to inhaled pollutants. Thus respiratory, immunological, cardiovascular, and other disorders may be developed following such exposures; however, further toxicological and larger scale molecular epidemiological studies must be done to fully understand the mechanism of action of these TPE emitted nanoparticles. Major research gaps have also been identified. Among them, a methodical risk assessment based on "real world" exposures rather than on the toner particles alone needs to be performed to provide the much-needed data to establish regulatory guidelines protective of individuals exposed to TPE emissions at both the occupational and consumer level. Industry-wide molecular epidemiology as well as mechanistic animal and human studies are also urgently needed.

Classifying oxidative stress by F2-isoprostane levels across human diseases: A meta-analysis

The notion that oxidative stress plays a role in virtually every human disease and environmental exposure has become ingrained in everyday knowledge. However, mounting evidence regarding the lack of specificity of biomarkers traditionally used as indicators of oxidative stress in human disease and exposures now necessitates re-evaluation. To prioritize these re-evaluations, published literature was comprehensively analyzed in a meta-analysis to quantitatively classify the levels of systemic oxidative damage across human disease and in response to environmental exposures.

In this meta-analysis, the F₂-isoprostane, 8-iso-PGF_2α, was specifically chosen as the representative marker of oxidative damage. To combine published values across measurement methods and specimens, the standardized mean differences (Hedges’ g) in 8-iso-PGF_2α levels between affected and control populations were calculated.

The meta-analysis resulted in a classification of oxidative damage levels as measured by 8-iso-PGF_2α across 50 human health outcomes and exposures from 242 distinct publications. Relatively small increases in 8-iso-PGF_2α levels (g<0.8) were found in the following conditions: hypertension (g=0.4), metabolic syndrome (g=0.5), asthma (g=0.4), and tobacco smoking (g=0.7). In contrast, large increases in 8-iso-PGF_2α levels were observed in pathologies of the kidney, e.g., chronic renal insufficiency (g=1.9), obstructive sleep apnoea (g=1.1), and pre-eclampsia (g=1.1), as well as respiratory tract disorders, e.g., cystic fibrosis (g=2.3).

In conclusion, we have established a quantitative classification for the level of 8-iso-PGF_2α generation in different human pathologies and exposures based on a comprehensive meta-analysis of published data. This analysis provides knowledge on the true involvement of oxidative damage across human health outcomes as well as utilizes past research to prioritize those conditions requiring further scrutiny on the mechanisms of biomarker generation.

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Oxidative damage is highly variable in human conditions as measured by F₂-isoprostanes.

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Respiratory tract and urogenital diseases have the highest F₂-isoprostanes.

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Cancer and cardiovascular diseases have surprisingly low F₂-isoprostanes.

Occupational exposure to photocopiers and their toners cause genotoxicity

Photocopier machines are inevitable office equipment, but they are also sources of air pollution. Millions of people across the world are involved in the operation and maintenance of photocopiers. We aimed to evaluate the potential genotoxic effects of exposure to photocopiers in photocopier operators and maintenance personnel by Comet assay. This study involved 50 photocopier operators, 61 maintenance personnel and 52 controls. Both the photocopier exposed groups exhibited significantly increased DNA damage when compared to controls. Cumulative exposure to photocopiers was the most significant contributor for genotoxicity ( p < 0.001). Genotoxicity among photocopier maintenance personnel may be due to the presence of carbon black, iron, silicon, magnetite and the high levels of other elements in the photocopier toners. Genotoxicity among photocopier operators might be due to exposure to high levels of particulate matter and volatile organic compounds emitted by photocopiers during operation. Research is essential to improve toner manufacturing processes and chemical composition of toners to reduce genotoxicity. Clean technologies are the need of the day to cut down on particulate matter and volatile organic compound emissions from photocopiers.

Restrictive Pattern of Pulmonary Symptoms among Photocopy and Printing Workers: A Retrospective Cohort Study

BACKGROUND

According to the growth of photocopier usage in workplaces, the potential risk of occupational exposure to the airborne chemicals has been raised up. Hence, monitoring the photocopy worker's respiratory functions seems to be necessary. We aimed to evaluate the respiratory health on photocopy and printing workers so that a reliable description can be made about their occupational hygiene.

METHODS

This study was performed in Shiraz, southwest Iran in 2014 and a group of 150 photocopy and printing workers were surveyed as exposed group in addition to a group of 114 office staff as unexposed group. The respiratory standard questionnaire was used to evaluate the prevalence of respiratory symptoms among the selected staff. Pulmonary function indexes including VC, FVC, FEV1 and the FEV1/FVC ratio were calculated. Finally, t-test, Chi Square and multiple logistic regressions were conducted.

RESULTS

VC, FVC and FEV1 in photocopy and printing workers were lower than the unexposed group of which these differences for FVC and FEV1 were statistically significant (P<0.05). Moreover, the prevalence of all respiratory symptoms, except the shortness of breath, in exposed group was more than the unexposed group and the prevalence of coughing and wheezing was statistically significant (P<0.05). There was a significant difference in respiratory symptoms (cough and wheezing) between two groups after controlling for confounding variables, OR: 2.61 (95% CI: 1.21, 5.62) and 2.92 (95% CI: 1.25, 6.84), respectively.

CONCLUSIONS

The prevalence of excess respiratory symptoms along with pattern of pulmonary restrictive sings in photocopy and printing workers revealed that the workplace conditions can result in occupational respiratory diseases.

Occupational exposure to nanoparticles at commercial photocopy centers

Photocopiers emit high levels of nanoparticles (PM0.1). To-date little is known of physicochemical composition of PM0.1 in real workplace settings. Here we perform a comprehensive physicochemical and morphological characterization of PM0.1 and raw materials (toners and paper) at eight commercial photocopy centers that use color and monochrome photocopiers over the course of a full week. We document high PM0.1 exposures with complex composition and several ENM in toners and PM0.1. Daily geometric mean PM0.1 concentrations ranged from 3700 to 34000 particles/cubic-centimeter (particles/cm(3)) (GSD 1.4-3.3), up to 12 times greater than background, with transient peaks >1.4 million particles/cm(3). PM0.1 contained 6-63% organic carbon, <1% elemental carbon, and 2-8% metals, including iron, zinc, titania, chromium, nickel and manganese, typically in the <0.01-1% range, and in agreement with toner composition. These findings document widespread ENM in toner formulations and high nanoparticle exposures are an industry-wide phenomenon. It further calls attention to the need to substantially redesign the interface of this technology with workers and consumers.

Impact of exposure to wood dust on genotoxicity and cytotoxicity in exfoliated buccal and nasal cells

Wood dust was classified by the IARC as a human carcinogen which causes sinonasal tumours. However, the exposure in different industries varies strongly and the risks of workers depend on the specific situation which can be assessed by the use of biomonitoring methods. The aim of this study was to investigate the workers who are exposed to low dust levels (below the permitted concentrations) with cytogenetic and biochemical methods. Micronuclei (MNi) which are indicative for genomic damage, nuclear buds which reflect gene amplification, binucleated cells which are caused by mitotic disturbances and acute cytotoxicity parameters (pyknosis, karyorrhexis, condensed chromatin, karyolysis) were monitored in buccal and nasal cells of workers of a veneer factory (n = 51) who are exposed to volatile wood-derived compounds, in carpenters of a furniture factory which use no synthetic chemicals (n=38) and in a control group (n = 65). Additionally, markers were measured in blood plasma which reflect inflammations (C-reactive protein, CRP) and the redox status, namely malondialdehyde (MDA) and oxidised low density proteins (oxLDL). No induction of micronucleated cells was observed in both epithelia in the two exposure groups while all other nuclear anomalies except pyknosis were increased; also one health-related biochemical marker (MDA) was significantly elevated in the workers. Taken together, the results of our study show that exposure to low levels of wood dust does not cause formation of MNi indicating that the cancer risks of the workers are not increased as a consequence of genetic damage while positive results were obtained in earlier studies with workers who are exposed to high dust levels. However, our findings indicate that wood dust causes cytotoxic effects which may lead to inflammations.

Biomarker as a research tool in linking exposure to air particles and respiratory health

Some of the environmental toxicants from air pollution include particulate matter (PM₁₀), fine particulate matter (PM_2.5), and ultrafine particles (UFP). Both short- and long-term exposure could result in various degrees of respiratory health outcomes among exposed persons, which rely on the individuals' health status. Methods. In this paper, we highlight a review of the studies that have used biomarkers to understand the association between air particles exposure and the development of respiratory problems resulting from the damage in the respiratory system. Data from previous epidemiological studies relevant to the application of biomarkers in respiratory system damage reported from exposure to air particles are also summarized. Results. Based on these analyses, the findings agree with the hypothesis that biomarkers are relevant in linking harmful air particles concentrations to increased respiratory health effects. Biomarkers are used in epidemiological studies to provide an understanding of the mechanisms that follow airborne particles exposure in the airway. However, application of biomarkers in epidemiological studies of health effects caused by air particles in both environmental and occupational health is inchoate. Conclusion. Biomarkers unravel the complexity of the connection between exposure to air particles and respiratory health.

Overview of the National Occupational Mortality Surveillance (NOMS) system: leukemia and acute myocardial infarction risk by industry and occupation in 30 US states 1985-1999, 2003-2004, and 2007

BACKGROUND

Cancer and chronic disease are leading causes of death in the US with an estimated cost of $46 billion.

METHODS

We analyzed 11 million cause-specific deaths of US workers age 18-64 years in 30 states during 1985-1999, 2003-2004, and 2007 by occupation, industry, race, gender, and Hispanic origin.

RESULTS

The highest significantly elevated proportionate leukemia mortality was observed in engineers, protective service, and advertising sales manager occupations and in banks/savings &loans/credit agencies, public safety, and public administration industries. The highest significantly elevated smoking-adjusted acute myocardial infarction mortality was noted in industrial and refractory machinery mechanics, farmers, mining machine operators, and agricultural worker occupations; and wholesale farm supplies, agricultural chemical, synthetic rubber, and agricultural crop industries.

CONCLUSIONS

Significantly elevated risks for acute myocardial infarction and leukemia were observed across several occupations and industries that confirm existing reports and add new information. Interested investigators can access the NOMS website at http://www.cdc.gov/niosh/topics/NOMS/.

An assessment of ozone levels, UV radiation and their occupational health hazard estimation during photocopying operation

This study investigates the levels of ozone concentration along with an ultraviolet (UV) and visible spectral radiation at eight photocopy centers in an academic institute, Delhi. Sampling was done in two types of locations, i.e., basement photocopy centers (BPC) and ground floor photocopy centers (GPC) for 8h. Measurements of levels of ozone, UV and visible radiation were done by ozone analyzer, UV radiometer and Field spectra instrument, respectively. Results show that the hourly mean concentration of ozone was observed to be in the range of 1.8-10.0 ppb and 5.3-45.8 ppb for BPC and GPC, respectively. In terms UV radiations, energy lies between 5.0×10(-3) and 7.0×10(-3) mW/cm(2) for ultraviolet A (UVA), 1.0×10(-3) and 2.0×10(-3) mW/cm(2) for ultraviolet B (UVB) and 6.0×10(-3) and 8.0×10(-3) mW/cm(2) for ultraviolet C (UVC). Correlation between the UV radiations and ozone production observed was statistically insignificant. To know the health hazard occurred to the workers, the standard erythema dose (SED) value was calculated for emitting UV radiation. The SED was estimated to be in the range of 0.02-0.04 and 0.02-0.32 for direct and indirect methods which is less than the guideline prescribed by Commission Internationale del' Eclairage (CIE). In nutshell, person involved in photocopy operation for their livelihood must be trained and should have knowledge for the long term gradual build up health problems due to ozone and UV production from photocopier. The manufactures should be ultimated with the significant ozone production, so that photocopier machine can be redesigned.