Exposure to BTEX concentration and the related health risk assessment in printing and copying centers

Occupational exposure to organic solvents and risk of bladder cancer

BACKGROUND

Bladder cancer has been linked to several occupations that involve the use of solvents, including those used in the dry-cleaning industry.

OBJECTIVES

We evaluated exposure to solvents and risk of bladder cancer in 1182 incident cases and 1408 controls from a population-based study.

METHODS

Exposure to solvents was quantitatively assessed using a job-exposure matrix (CANJEM). Exposure to benzene, toluene and xylene often co-occur. Therefore, we created two additional sets of metrics for combined benzene, toluene and xylene (BTX) exposure: (1) CANJEM-based BTX metrics and (2) hybrid BTX metrics, using an approach that integrates the CANJEM-based BTX metrics together with lifetime occupational histories and exposure-oriented modules that captured within-job, respondent-specific details about tasks and chemicals. Adjusted odds ratios (ORs) and 95% confidence intervals (95% CI) were estimated using logistic regression.

RESULTS

Bladder cancer risks were increased among those ever exposed to benzene (OR = 1.63, 95% CI: 1.14-2.32), toluene (OR = 1.60, 95% CI: 1.06-2.43), and xylene (OR = 1.67, 95% CI: 1.13-2.48) individually. We further observed a statistically significant exposure-response relationship for cumulative BTX exposure, with a stronger association using the hybrid BTX metrics (ORQ1vsUnexposed = 1.26, 95% CI: 0.83-1.90; ORQ2vsUnexposed = 1.52, 95% CI: 1.00-2.31; ORQ3vsUnexposed = 1.88, 95% CI: 1.24-2.85; and ORQ4vsUnexposed = 2.23, 95% CI: 1.35-3.69) (p-trend=0.001) than using CANJEM-based metrics (p-trend=0.02).

IMPACT

There is limited evidence about the role of exposure to specific organic solvents, alone or in combination on the risk of developing bladder cancer. In this study, workers with increasing exposure to benzene, toluene, and xylene as a group (BTX) had a statistically significant exposure-response relationship with bladder cancer. Future evaluation of the carcinogenicity of BTX and other organic solvents, particularly concurrent exposure, on bladder cancer development is needed.

Temperature-modulated sensing characteristics of ultrafine Au nanoparticle-loaded porous ZnO nanobelts for identification and determination of BTEX

The identification and determination of benzene, toluene, ethylbenzene, and xylene (BTEX) has always been a formidable challenge for chemiresistive metal oxide sensors owing to their structural similarity and low reactivity, as well as the intrinsic cross sensitivity of metal oxides. In this paper, a temperature-modulated sensing strategy is proposed for the identification and determination of BTEX using a high-performance chemiresistive sensor. Ultrafine Au nanoparticle-loaded porous ZnO nanobelts as sensing materials were synthesized through an exchange reaction followed by thermal oxidation, which exhibited high response toward BTEX. Under dynamic modulation of working temperature, the distinguishable characteristic curves were demonstrated for each BTEX compound. By employing the linear discrimination and convolutional neural network analyses, highly effective BTEX identification was achieved among all investigated volatile organic compounds, which is difficult to realize for single chemiresistive sensors at constant working temperatures. Furthermore, quantitative analysis of BTEX concentrations was accomplished by establishing the relationship between concentration and response at specific points on their response curves. This developed strategy is expected to pave a new way for constructing highly sensitive gas sensors for the identification and analysis of hazardous gases, thereby enhancing their applicability in environmental monitoring.

Health risk assessment of exposure to benzene, toluene, ethyl benzene, and xylene in shoe industry-related workplaces

Benzene, toluene, ethyl benzene, and xylene (BTEX) are prevalent pollutants in shoe industry-related workplaces. The aim of this study was to assess exposure to BTEX and their carcinogenic and non-carcinogenic risks in shoe-industry-related workplaces. This study was carried out at different shoe manufactures, small shoe workshop units, shoe markets, and shoe stores in Tabriz, Iran in 2021. Personal inhalation exposure to BTEX was measured using the National Institute for Occupational Safety and Health (NIOSH) 1501 method. Carcinogenic and non-carcinogenic risks due to inhalation exposure to BTEX were estimated by United States Environmental Protection Agency (U.S. EPA) method based on Mont Carlo simulation. Results showed that the concentrations of benzene and toluene were higher than the threshold limit value (TLV) in both gluing and non-gluing units of shoe manufactures. The total carcinogenic risk (TCR) due to exposure to benzene and ethyl benzene was considerable in all shoe industry-related workplaces. Also, the hazard index (HI) as a non-carcinogenic index was higher than standard levels in all shoe industry-related workplaces. Therefore, shoe industry-related workers are at cancer and non-cancer risks due to exposure to BTEX. Prevention measures need to be implemented to reduce the concentration of BTEX in shoe industry-related workplaces.

BTEX in indoor air of barbershops and beauty salons: Characterization, source apportionment and health risk assessment

BACKGROUND

Volatile organic compounds, mainly BTEX, are among the pollutants of concern in beauty salons and barbershops that threaten both staff personnel and clients' health. This study aimed to determine the concentration of BTEX in barbershops and beauty salons and assess the carcinogenic and non-carcinogenic risks based on the actual risk coefficients. Also, possible sources of BTEX were determined.

METHOD

Samples were collected by passive sampling. Quantitative and qualitative measurements of BTEX compounds were performed using gas chromatography-mass spectrometry (GC-MASS). Subsequently, the health risks were assessed according to the US Environmental Protection Agency. SPSS24 software and positive matrix factorization (PMF) analysis were used for statistical analysis and source apportionment respectively.

RESULTS

Toluene is the most abundant compound in beauty salons, with a maximum concentration of 219.4 (μg/m3) in beauty salons. Results indicated that the mean ELCR value estimated for benzene regarding female staff exposure (1.04 × 10-5) was higher than that for men (4.05 × 10-6). Also, ELCR values of ethylbenzene for staff exposure were 2.08 × 10-6 and 3.8 × 10-6 for men and women, respectively, and possess possible carcinogenesis risks.

CONCLUSION

Use of solvents and cosmetic products, improper heating systems, and type of service are the sources that probably contribute to BTEX emissions in beauty salons. It is necessary to follow health guidelines and conduct continuous monitoring for their implementation, in addition to setting a mandated occupational regulation framework or air quality requirements, to improve the health conditions in beauty salons.

Health risk assessment of BTEX compounds (benzene, toluene, ethylbenzene and xylene) in different indoor air using Monte Carlo simulation in zahedan city, Iran

The presence of benzene, toluene, ethylbenzene, and xylene compounds (BTEX) in the breathing air outside and inside buildings is one of the most significant problems related to human health today. This study was performed to determine the concentration of BTEX pollutants in indoor environments. PhoCheck was used to detect the concentration of BTEX compounds. In this study, the concentration (BTEX pollutant) was assessed in four indoor spaces, including restaurants, laundries, hair salons, and photocopying centers. The results showed that the average concentration of all four searched compounds was higher than the recommended limit of the Environmental Protection Agency (EPA). The results of carcinogenic risk assessment by benzene and ethylbenzene compounds show 2153 × 10-4 and 913 × 10-5 respectively. The HQ values for toluene and xylene were 1.397 and 0.505, respectively, indicating that exposure to toluene alone may have adverse effects on human health, while exposure to xylene alone has no adverse effects. The hazard index (HI) for toluene and xylene pollutants was higher than one. An HI value higher than one means that the two contaminants toluene and xylene in the air we breathe may have adverse effects on human health. As a result, the necessary control measures should be taken to prevent the unfavorable effects of these two pollutants.

Monte Carlo-based probabilistic risk assessment for cement workers exposed to heavy metals in cement dust

This study assessed the carcinogenic and non-carcinogenic health risks of cement plant workers exposed to chromium (Cr), arsenic (As), cadmium (Cd), and lead (Pb) in cement dust using a probabilistic approach. Air samples were collected according to NIOSH 7900 and OSHA ID-121 methods and analyzed by an graphite furnace atomic absorption spectrometer. The EPA inhalation risk assessment model and Monte Carlo simulation were utilized to assess the health risks. Sensitivity analysis was used to determine the influencing parameters on health risk. The average concentrations of As and Pb exceeded the occupational exposure limit (OEL), reaching a maximum of 3.4 and 1.7 times the OEL, respectively, in the cement mill. Individual metals' cancer risk exceeded the 1E-4 threshold in ascending order of Cd < As < Cr. The mean cancer risk of Cr ranged from 835E-4 (in raw mill) to 2870E-4 (in pre-heater and kiln). Except for Cd, the non-cancer risk of metals exceeded the standard (hazard index, HQ = 1) in the ascending order of Pb < As < Cr. The mean HQ of Cr ranged from 162.13 (in raw mill) to 558.73 (in pre-heater and kiln). After adjusting for control factors, the cancer and non-cancer risks remained over the respective recommended levels. Sensitivity analysis revealed that the concentration of Cr was the most influential parameter on both carcinogenic (78.5%) and non-carcinogenic (88.06%) risks. To protect the health of cement factory employees, it is recommended to minimize cement dust emissions, implement job rotation, and use raw materials with low levels of heavy metals.

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.

Explication on distribution patterns of volatile organic compounds in petro-chemistry and oil refineries of China using a species-transport model and health risk assessment

Volatile organic compounds (VOCs) from industrial emissions have attracted great attention due to their negative effects on human, but there is lack of deterministic air quality model for VOC emissions. In this study, airborne VOCs from a typical petrochemical and oil refinery region, Lanzhou, Gansu province of China, were on-site measured. The regional pollution patterns were investigated using a species transport model and the health risks were evaluated. The spatial distribution of VOCs showed that 87.5 % of the airborne VOCs were benzene, toluene, ethylbenzene, and xylene having higher concentration (146 μg/m³) in the north direction oil refinery industrial areas. The concentrations of toluene and benzene were as high as 41.5 and 33.3 μg/m³ in the 4 km² area away from the petrochemical emission source, respectively, and the concentration of o-/m + p-xylene was up to 79.7 μg/m³. Based on the measured concentration data, the numerical results showed that the accumulation of high concentration of VOC species by mass transfer in the region is related to the atmospheric diffusion driven by downward-moving air over the valley areas. Non-carcinogenic risk assessments showed that airborne benzene exposure had acceptable hazard quotient of 0.185 for adults, which was 1.8 times of children's (0.102), whereas it was found that a high carcinogenic risk (>10^-4) from benzene in several sampling sites and diffuse distance become significant for carcinogenic risk. This study verified the effectiveness of VOC atmospheric diffusion model through a large number of on-site monitoring data, providing data support for model-based risk assessment.

Study on the Fingerprint and Atmospheric Activity of Volatile Organic Compounds from Typical Industrial Emissions

China is prone to severe surface ozone pollution in summer, so it is very important to understand the source of volatile organic compounds (VOCs) to control ozone formation. In this work, the emission characteristics of 91 VOC components from the plastic products industry, packaging and printing industries, printing ink industry, furniture manufacturing and vehicle manufacturing industries were studied. The results show that there are significant differences between these sources, and for the plastic products industry, alkanes (48%) are the most abundant VOCs. The main emission species in the packaging and printing industry are OVOCs (36%) and alkanes (34%). The proportion of OVOCs in the printing ink (73%) and furniture manufacturing industries (49%) is dominated by VOC emissions; aromatic hydrocarbons (33%), alkanes (33%), and OVOCs (17%) are the main emission species in the vehicle manufacturing industry. At the same time, the ozone generation potential (OFP) and secondary organic aerosol formation potential (SOA) of anthropogenic VOC emissions were evaluated, and the top 10 contributors to OFP and SOA were identified. Toluene, o-xylene, and m-xylene had a significant tendency to form OFP or SOA. Then, a health risk assessment of VOC components was carried out. These data can supplement the existing VOC emission characteristics of anthropogenic emissions, thus enriching the research progress of VOC emission sources.

Probabilistic health risk assessment of occupational exposure to crystalline silica in an iron foundry in Urmia, Iran

This study aimed to quantify the exposure of foundry workers to crystalline silica and associated cancer and non-cancer health risks using a probabilistic approach. Breathing zone air samples were collected according to the NIOSH 7602 method and analyzed using Fourier transform infrared spectroscopy. The health risks posed by crystalline silica were then assessed using the EPA-developed inhalation risk assessment model and Monte Carlo simulation. The sensitivity analysis was also conducted to determine the contribution of input parameters to the health risks. The mean concentration of crystalline silica in six foundry stations ranged from 0.029 to 0.064 mg m-3, exceeding the occupational exposure limits. The average values of cancer risks were greater than the USEPA level, i.e., 1E - 6 in all workstations of the foundry. Workers in sand preparation and molding stations suffered the greatest cancer risks, with the mean value of 2.35E - 5 and 2.10E - 5, respectively. Non-cancer hazard quotient exceeded 1 in all foundry stations ranging from 1.56 (in melting and pouring) to 3.37 (in sand preparation). The 95% upper-bound values of the health risks decreased by 77.52% and 56.77%, assuming the use of engineering controls and wearing respirators by workers, respectively. Sensitivity analyses indicate that concentration was the most sensitive factor contributing to the carcinogenic (46.13%) and non-carcinogenic (67.08%) risks. These findings can aid managers in gaining a better understanding of the silica risks faced by foundry workers and the role of engineering controls and respirators in protecting workers' health.

Temporary reduction in VOCs associated with health risk during and after COVID-19 in Maharashtra, India

A novel coronavirus has affected almost all countries and impacted the economy, environment, and social life. The short-term impact on the environment and human health needs attention to correlate the Volatile organic compounds (VOCs) and health assessment for pre-, during, and post lockdowns. Therefore, the current study demonstrates VOC changes and their effect on air quality during the lockdown. The findings of result, the levels of the mean for total VOC concentrations were found to be 15.45 ± 21.07, 2.48 ± 1.61, 19.25 ± 28.91 µg/m³ for all monitoring stations for pre-, during, and post lockdown periods. The highest value of TVOCs was observed at Thane, considered an industrial region (petroleum refinery), and the lowest at Bandra, which was considered a residential region, respectively. The VOC levels drastically decreased by 52%, 89%, 80%, and 97% for benzene, toluene, ethylbenzene, and m-xylene, respectively, during the lockdown period compared to the previous year. In the present study, the T/B ratio was found lower in the lockdown period as compared to the pre-lockdown period. This can be attributed to the complete closure of non-traffic sources such as industries and factories during the lockdown. The Lifetime Cancer Risk values for all monitoring stations for benzene for pre-and-post lockdown periods were higher than the prescribed value, except during the lockdown period.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s10874-022-09440-5.

Effect of portable air purifier on indoor air quality: reduced exposure to particulate matter and health risk assessment

We sought to investigate the impact of air purifiers in the removal of particular matter (PM)₁₀, PM_2.5, PM_1, and particle number concentration (PNC) in the indoor air of dormitories located at Iran's largest medical university, Tehran University of Medical Sciences. Twelve rooms were selected and randomly assigned to two rooms: sham air purifier system deployed room (SR) and true air purifier system deployed room (TR). All study samples were drawn simultaneously from assigned rooms using portable GRIMM dust monitors for 24 h. The PM monitors of air were positioned in the middle of each room next to the air purifier at the height of the breathing zone (1.5 m in height). The mean PM₁₀, PM_2.5, PM₁, and PNC removal efficiency in rooms with and without a smoker were measured to be 40.7 vs 83.8%, 31.2 vs 78.4%, 29.9 vs 72.3%, and 44.3 vs 75.6%, respectively. The results showed that smoking is an important influencing factor on the indoor air quality; smoking lowered the removal efficiency of PM₁₀, PM_2.5, PM₁, and PNC by 43%, 47%, 43%, and 31%, respectively. An air purifier could decline the PM₁₀ and PM_2.5 even lower than the WHO 24-h guideline level in non-smoker rooms. This study revealed that using household air purifiers in rooms with smokers and non-smokers significantly reduces the non-carcinogenic risks of exposure to PM₁₀ and PM_2.5.

Urinary concentrations of BTEX in waterpipe smokers and nonsmokers: Investigating the influence of conventional activities and multiple factors

The aim of this study was to compare the concentrations of the benzene, toluene, ethylbenzene, and xylene (BTEX) compounds in the urine of smokers and the control group considering the role of age, weight, job, history of waterpipe and cigarette smoking, and driving time. The chemicals in the urine of 99 smokers and 31 nonsmokers were extracted by liquid-liquid extraction method and their concentrations were measured by liquid injection GC/MS. The mean concentration of benzene, toluene, ethylbenzene, m-xylene, o-xylene, p-xylene, and total BTEX in waterpipe smokers were found to be 471.40, 670.90, 127.91, 167.64, 90.62, 46.04, and 1574.50 ng/g. creatinine, respectively. For the waterpipe&cigarette smokers, the concentration of the compounds were 708.00, 959.00, 146.40, 192.50, 93.30, 53.07, and 2152.00 ng/g.creatinine, respectively. For nonsmokers the concentrations of these compounds were 88.12, 140.40, 36.68, 57.29, 31.53, 26.21, and 380.30 ng/g.creatinine, respectively. Driving time, waterpipe smoking and cigarette smoking were positively associated with BTEX concentration (p < 0.05). Fruity tobacco showed higher concentrations of BTEX compared to the regular tobacco, and athlete persons had les urinary BTEX than the non-athletes. There was not significant correlation between the BTEX and age, height, weight, and BMI. High concentrations of BTEX compounds in the urine of waterpipe and cigarette smokers compared to nonsmokers indicate that waterpipe and cigarette can be an important source of exposure to these compounds and the known adverse effects of these compounds, especially carcinogenicity, threaten the health of smokers.

Occupational exposure to BTEX and styrene in West Asian countries: a brief review of current state and limits

The aim of introducing occupational exposure limits (OELs) is to use them as a risk management tool in order to protect workers' health and well-being against harmful agents at the workplace. In this review we identify OELs for benzene, toluene, ethylbenzene, xylene (BTEX), and styrene concentrations in air and assess occupational exposure to these compounds through a systematic literature search of publications published in West Asian countries from 1980 to 2021. OELs for BTEX and styrene have been set in Iran and Turkey to levels similar to those in European countries and the US. The search yielded 49 full-text articles that cover studies of exposure assessment in six countries, but most (n=40) regard Iran. Average occupational exposure to benzene of workers in oil-related industries is higher than recommended OEL, while average occupational exposure to other compounds is lower than local OELs (where they exist). Currently, information about levels of occupational exposure to BTEX and styrene is insufficient in West Asian countries, which should be remedied through OEL regulation and application. Furthermore, coherent research is also needed to determine actual levels of occupational exposure, dose-responses, and the economic and technical capacity of local industries to address current issues.

Assessing BTEX concentrations emitted by hookah smoke in indoor air of residential buildings: health risk assessment for children

Hookah smoke is one of the major indoor sources of Volatile Organic Compounds (VOCs), including Benzene, Toluene, Ethylbenzene, and Xylenes (BTEX). The present study aimed to investigate potential exposure to BTEX compounds among primary school children whose parents smoked hookah at home. BTEX concentrations in indoor air were measured in 60 residential buildings of Khesht, southwestern Iran (case = 30 and control = 30). Target compounds were sampled by charcoal tubes, and the samples were then analyzed by GC-FID. Monte Carlo simulation was used to assess the carcinogenic and non-carcinogenic risks of BTX exposure for the children aged 7-13 years. The concentrations of benzene (7.19 ± 3.09 vs. 0.82 ± 0.5 μg/m³), toluene (1.62 ± 0.69 vs. 0.3 ± 0.22 μg/m³), and xylenes (2.9 ± 1.66 vs. 0.31 ± 0.22 μg/m³) were considerably higher in the indoor air of the case houses compared with the control houses (p < 0.05). The Incremental Lifetime Cancer Risk (ILCR) of benzene for non-smoking and smoking houses were estimated 1.8 × 10^-6 and 15 × 10^-6, respectively, exceeding the recommendations of the World Health Organization (WHO) and the Environmental Protection Agency (EPA) (1 × 10^-6). Moreover, Hazard Quotients (HQs) of all BTX compounds were < 1. The indoor benzene concentration was significantly influenced by the floor at which families lived and type of the kitchen. In order to prevent children's exposure to BTX emitted by hookah, banning indoor smoking is the only way to eliminate these compounds in the indoor air.

Bacteria bioaerosol in the indoor air of educational microenvironments: Measuring exposures and assessing health effects

Exposure to bioaerosols has been identified to be linked the incidence of various health effects, i.e., infectious diseases, acute toxic effects, allergies, and cancer. The aim of this study was to determine the bacterial bioaerosols in the indoor air of the educational environments of Ardabil universities and to evaluate the exposure and to determine its health risk. In this cross-sectional study, different sections of the educational environments of Ardabil universities were studied. For differential diagnosis of bacteria, methods such as gram staining and biochemical detection methods including DNAse, catalase, oxidase, coagulase, bile esculin hydrolysis test, urease, citrate test, antibiotic resistance to novobiocin and Bacitracin, optochin, glucose uptake, and other differential tests were used. For sampling, a single-stage Anderson sampler was used at a flow rate of 28.3 l at a duration of 10 min per minute. The results showed that, in medical school of Ardabil University of Medical Sciences, the average concentration of bacteria in the outdoor air of school, halls, classes and rooms of professors and staff were 18, 88.4, 76.6, and 77.4 CFU/m³, respectively, and, in Ardabil Islamic Azad University, the average bacterial concentration was 103, 97, 124, and 132 CFU/m³ in the outdoor air of the schools, halls, classrooms, and rooms of professors and staff, respectively. The predominant bacterial species in indoor air are S. aureus, S. epidermidis, Actinomycetes, and Bacillus, respectively. As results indicated, the concentration of bacterial bioaerosols in indoor air is within the standard levels, but due to frequency of bacterial species, occurrence of different in lung and intestinal diseases can be expected among faculty, staff and students in the long-term.