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The CS-TPP nanoparticles were synthesized and their efficiency for removal of arsenic (V) ions at the optimum conditions was investigated. The optimum conditions for CS-TPP nanoparticles were obtained with the mass ratio of tripolyphosphate to chitosan of 1: 2 and pH = 5.0. The experimental data for the adsorption of As (V) ions followed the Freundlich adsorption isotherm and the maximum adsorption capacity was 77 mg/g at pH = 6.0. All isotherm experiments were performed at room temperature (25 °C). The crosslinking of sodium tripolyphosphate with the chitosan led to a decrease in crystallinity of the formed particles which then resulted in an improvement in metal ion sorption properties.

This study aimed to identifying the presence of SARS-CoV-2 RNA in raw and treated wastewater during the COVID-19 outbreak in Tehran, Qom and Anzali cities (Iran). From three wastewater treatment plants (WWTPs), 28 treated and untreated wastewater composite samples were collected from April 4 to May 2, 2020. In this study, polyethylene glycol 6000 (PEG 6000) was used through one-step real-time quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) for identification of RNA viruses. SARS-CoV-2 RNA was elicited from wastewater composite samples in all inlet samples taken from the three above mentioned cities. The results of outlet samples were as follows: 1) Results from Qom and East Anzali outlets showed no trace of SARS-CoV-2 RNA despite the difference in treatment disinfection method used (chlorine vs. ultraviolet (UV) disinfection). 2. In Tehran, SARS-CoV-2 RNA was not detected in any of the outlet samples taken from the modules disinfected by UV. Out of the four samples taken from the modules disinfected by chlorine, two were positive for the SARS-CoV-2 RNA which could have been caused by deficiencies in operation and maintenance. It can be concluded that meeting the standards of operation and maintenance (O&M) in WWTPs can considerably ensure that wastewater does not act as one of the roots of transmission for the disease.

This work reports a characterization of PAHs-PM10, including associated health effects in the largest composting facility in Tehran, Iran. Measured PAHs-PM10 stemmed primarily from petrogenic sources with mean concentrations between 231.19 to 401.25 ng m−3. The distribution pattern of PAHs (in terms of ring number) exhibited the following order when combining all sites: 3 > 4 > 5 > 6 > 2 rings. The average cumulative excess lifetime cancer risk values estimated for PAHs-PM10 surpassed the U.S. EPA limit (1 × 10−6): refining site (3.31 × 10−4) > processing site (1.75 × 10−4) > aeration site (9.81 × 10−5).

Solid waste components can be recycled in waste paper and cardboard sorting plants (WPCSP) through a multistep process. This work collected 15 samples every six days from each of the 9 points selected to study the processes taking place in a WPCSP (135 particulate matter samples total). Examining the concentration and size fraction of particulate matter (i.e., PM

While chlorination is critical for water disinfection, a knowledge gap includes the nature of free residual chlorine (FRC) decay, which was investigated using four physical methods (SSA, SSR with a...

The synthesis of compounds with an excellent adsorption capability plays an essential role to remove contaminants such as phthalic acid esters (PAEs) with potential carcinogenic characteristics from different food products. In this context, for the first time, a novel adsorbent (MWCNT-Fe3O4/Ag) was synthesized by using iron (magnetic agent), and silver (catalytic and surface enhancer agent) to further approach in a magnetic SPE-GC/MS method for determining of PAEs in carbonated soft drink samples. The limit of detection (LOD) and limit of quantification (LOQ) values of MSPE-GC/MS were determined in six PAEs as a range of 10.8–22.5 and 36–75 ng/L, respectively. Also, the calibration curves of PAEs were linear (R2 = 0.9981–0.9995) over the concentration level of 10.000 ng/L and the recoveries of the six PAEs were ranging from 96.60% to 109.22% with the RSDs less than 8%. Moreover, scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), X-ray diffraction (XRD), vibrating sample magnetometry (VSM) and transmission electron microscopy analyses (TEM) were utilized to characterize the produced MWCNT-Fe3O4/Ag. Based on the findings, the surface of MWCNT is relatively uniform, which became coarser after loading with Fe3O4/Ag particles. Also, EDX spectrum showed the carbon (C), iron (Fe), oxygen (O), Ag and copper (Cu) are the main components of synthesized MWCNTs-Fe3O4/Ag. The successful adhesion of Fe3O4/Ag on the texture of MWCNTs using a co-precipitation method was confirmed by XRD and FT-IR assays. Additionally, excellent crystallinity and clear lattice nanocrystals fringes of prepared MWCNT-Fe3O4/Ag was demonstrated by TEM analysis. Based on the obtained VSM images, the prepared sorbent (MWCNT-Fe3O4/Ag) has the good magnetic performance for magnetic separation and extraction processes. It was concluded that the synthesized MWCNT-Fe3O4/Ag could be used as an efficient adsorbent for determining contaminants such as PAEs in different beverage samples. Keywords: Magnetic solid phase extraction (MSPE), Multi-walled carbon nanotubes (MWCNTs), Iron oxide (Fe3O4), Silver (Ag), Phthalic acid esters (PAEs)

In recent years, recycling of municipal solid waste (MSW) has been recognized as one of the most efficient methods of waste management in terms of environmental benefits. This study investigates the energy savings and other environmental benefits of recycling of dry MSW collected in Shiraz, Iran (2018). The impact of different recycling rates (current = 15%, desirable = 50%, ideal = 80%) on environmental benefits and energy savings were assessed. The annual quantity of recycled components were defined as glass (735 tons), plastic carrier bags (555 tons), cardboard (3,874 tons), paper (3,806 tons), disposable plastic containers (287 tons), other types of metals (785 tons), disposable metallic containers (aluminum) (171 tons), other types of plastics (812 tons) and polyethylene terephthalate (PET) (887 tons). The results confirmed that recycling of paper and glass in three different scenarios resulted in a reduction of 1.01, 2.14, and 3.43 million tons of air pollutant emissions, respectively. By improving the recycling rates from 15 to 80%, overall energy savings can improve by between a factor of 3.5 to 5.5. Also, a reduction of approximately 2–3.5% in air pollutant emissions can be achieved by upgrading the current recycling program (15% recycling rate) to favorable and ideal conditions. Implications: In recent years, recycling of municipal solid waste (MSW) has been recognized as one of the most efficient methods of waste management in terms of environmental benefits. This study investigates the energy savings and other environmental benefits of recycling of dry MSW collected in Shiraz, Iran (2018). According to available data, there has been little effort for recycling in developing countries, and waste landfilling is recognized as the most favorable option in MSW management. The aim of this study was to characterize MSW components in Shiraz, Iran, and to quantify the environmental benefits and energy savings as result of paper, glass, and aluminum recycling. This work is novel in that there are no reports to our knowledge of the environmental benefits and energy savings resulting from different recycling scenarios including current (15%), desirable (50%), and ideal (80%) recycling for aluminum, paper, and glass. The results of this work have broad implications both for other regions owing to the pervasiveness of recycling facilities and also for developing countries that can strive towards the infrastructure needed to reach improved recycling scenarios.

The main aim of this study was to evaluate gamma radiation level in the mineral hot springs of Ardabil province in Iran. In addition, the cancer risk of gamma radiation was assessed for swimmers. Natural gamma radiation was measured using Ion Chamber Survey Meter 451B in 22 springs throughout the province. Gamma was measured at 20 cm and 100 cm above the ground level in 15 locations of each spring. Excess lifetime cancer risk was calculated to investigate the risk of exposure to gamma radiation. The highest and lowest annual absorbed dose rate of gamma were found to be 1.17(10-3) and 1.99(10-3) Sv/y at the height of 20 cm above the ground level and 5.26(10-4) and 1.52(10-3) Sv/y at the height of 100 cm above the ground level, respectively. Excess lifetime cancer risk ranged from 4.57(10-4) to 7.76(10-4) at the height of 20 cm and from 2.06(10-4) to 5.94(10-4) at the height of 100 cm which are lower than global average of 1.45(10-3) declared by the United Nations. Although the risk level in this study is lower than the global average, protective and preventive measures should be considered by individuals and authorities in these areas to reduce the effects of gamma radiation on the health of the swimmers.

Emissions of volatile organic compounds (VOCs) were studied during paper and cardboard recycling from a paper and cardboard solid waste recycling factory (PCSWRF). Data are summarized in this article for the following quantities for a PCSWRF during the winter in Tehran, Iran: VOC concentrations (μg m−3), the percentage of detected VOCs, exposure indices (Ei) of individual and total VOCs (TVOCs), inhalation lifetime cancer risk (LTCR) of VOCs, the hazard quotient (HQ) of VOCs, sensitivity analysis (SA) for VOC exposure in different age groups (birth to

This study reports a spatiotemporal characterization of formaldehyde and acetaldehyde in the summer and winter of 2017 in the urban area of Shiraz, Iran. Sampling was fulfilled according to EPA Method TO-11 A. The inverse distance weighting (IDW) procedure was used for spatial mapping. Monte Carlo simulations were conducted to evaluate carcinogenic and non-cancer risk owing to formaldehyde and acetaldehyde exposure in 11 age groups. The average concentrations of formal-dehyde/acetaldehyde in the summer and winter were 15.07/8.40 μg m−3 and 8.57/3.52 μg m−3, respectively. The formaldehyde to acetaldehyde ratios in the summer and winter were 1.80 and 2.43, respectively. The main sources of formaldehyde and acetaldehyde were photochemical generation, vehicular traffic, and biogenic emissions (e.g., coniferous and deciduous trees). The mean inhalation lifetime cancer risk (LTCR) values according to the Integrated Risk Information System (IRIS) for formaldehyde and acetaldehyde in summer and winter ranged between 7.55 × 10−6 and 9.25 × 10−5, which exceed the recommended value by US EPA. The average LTCR according to the Office of Environmental Health Hazard Assessment (OEHHA) for formaldehyde and acetaldehyde in summer and winter were between 4.82 × 10−6 and 2.58 × 10−4, which exceeds recommended values for five different age groups (Birth to

This study reports a spatiotemporal characterization of toluene, benzene, ethylbenzene, and xylenes concentrations (BTEX) in an urban hot spot in Iran, specifically at an bus terminal region in Shiraz. Sampling was carried out according to NIOSH Compendium Method 1501. The inverse distance weighting (IDW) method was applied for spatial mapping. The Monte Carlo simulation technique was applied to evaluate carcinogenic and non-carcinogenic risk owing to BTEX exposure. The highest average BTEX concentrations were observed for benzene in the morning (at 7:00-9:00 A.M. local time) (26.15 ± 17.65 µg/m3) and evening (at 6:00-8:00 P.M. local time) (34.44 ± 15.63 µg/m3). The benzene to toluene ratios in the morning and evening were 2.02 and 3.07, respectively. The main sources of BTEX were gas stations and a municipal solid waste transfer station. The inhalation lifetime cancer risk (LTCR) for benzene in the morning and evening were 1.96 × 10-4 and 2.49 × 10-4, respectively, which exceeds the recommended value by US EPA and WHO. The hazard quotient (HQ) of all these pollutants was less than 1. The results of this work have implications for public health near 'hot spots' such as IKBT where large populations are exposed to carcinogenic emissions.

In the current study, a novel magnetic solid phase extraction (MSPE) technique combined with a gas chromatography/mass spectroscopy (GC/MS) was developed to determine the phthalate ester content of bottled Doogh samples. Doogh is a yogurt-based drinking beverage, which is frequently consumed in Middle East and Balkans. It is produced by stirring yogurt in Chern separation machine and consists of substances such as water, yogurt, and salt in addition to aqueous extracts of native herbs. The magnetic multi-walled carbon nanotubes (MWCNT-Fe3O4) were used as adsorbents of phthalate acid esters (PAEs) due to a superior adsorption capability of hydrophobic compounds. In this context, the quantity of the extractable migrated phthalate esters (dibutyl phthalate (DBP), dimethyl phthalate (DMP), butyl benzyl phthalate (BBP), diethyl phthalate (DEP), di-N-octyl phthalate (DNOP), and bis (2-ethylhexyl) phthalate (DEHP)) from polyethylene terephthalate (PET) bottles into Doogh samples was measured. The correlation between the concentration of migrated PAEs and some factors such as the type of Doogh (gaseous and without gas), difference in brand (five brands), volume (1500 and 300 mL), and the storage time also was investigated. The migration level into Doogh samples was increased by incorporating of gas as well as increasing the volume of PET bottles. Also, with elaborating of storage time, the migration of some phthalates such as DEHP (the mean from 2419.85 ng L−1 in the first week to 2716.15 ng L−1 in the second month), DEP, and total phthalate was increased. However, no significant difference in concentrations of migrated phthalate esters among different examined brands was noted. Finally, the concentration of migrated PAEs from bottle into all the examined Doogh samples was below the defined standards by EPA; 6 μg/L for DEHP in drinking water.

This study aimed to assess hydrogen sulfide (H2S) concentrations in the pool indoor air of hot springs and its link to some physicochemical properties of the springs in Ardabil province. Twenty-two hot springs from different regions were selected and monitored for H2S concentrations using a portable gas meter. Respective mean concentrations of H2S in hot springs indoor air were 9.11 ± 11. Ghotour Souei hot springs had the highest concentration of H2S with a mean concentration of 29.4 ± 7.7 and 25.2 ± 8.16 ppm at the source and general pool areas, respectively. Oxidation-reduction potential and pH of the water were the most important factor influencing H2S concentrations in the hot springs. H2S concentrations in indoor air of Ardabil hot springs were noticeably higher than OEL-TWA and OEL-STEL, and therefore may pose important risks for human health on both short-and long-term exposures.

Nitrate has been identified as a major pollutant in water resources. In this study, two new adsorbents, namely, red local montmorillonite (RLM) and green local montmorillonite (GLM) were used as adsorbents, and their characteristics and performance in nitrate adsorption has been investigated. The most important factors in the adsorption process such as initial pH, adsorbent dosage, contact time and initial concentration of nitrate were investigated. Also, EDAX, BET, SEM and FTIR techniques were used to determine adsorbent characteristics. The results showed that the highest nitrate adsorption for both adsorbents obtained at low pH values, and removal efficiency increased by increasing the dosage and contact time and decreased by increasing the initial concentration of nitrate. EDAX technique showed that the amount of MgO in GLM and RLM were 2.6 and 1.4 respectively, indicating a double amount of MgO in GLM structure. MgO can have a very important role in nitrate adsorption but BET technique showed that the specific surface area of RLM is more than GLM. Overall results showed that the adsorption capacities of GLM and RLM were relatively high and the values were 89.2 and 87.7 mg/g, respectively. High adsorption capacity can nominate two new adsorbents for nitrate adsorption. Adsorption process followed the Langmuir isotherm and the experimental data followed the pseudo second-order kinetic. Also, the results of thermodynamic experiments showed that the adsorbing reaction for both adsorbents was exothermic and they occurred spontaneously.

In this study, at first were prepared novel multi-walled carbon nanotubes modified with catalytic nanoparticles of iron oxide and silver (MWCNTs-Fe3O4/Ag) by mixing the magnetic particles. Due to their excellent absorption and desorption capability towards hydrophobic compounds, the magnetic MWCNTs were used as adsorbent of magnetic solid-phase extraction (MSPE) to extract phthalate acid esters (PAEs). Our results showed the highest concentration of phthalate esters of bis(2-ethylhexyl)phthalate (DEHP) which is much higher than the standard level in the four samples (6766.6, 9201, 9301.6, and 14,008 ng/L). Finally, the established MSPE-GC/MS method was successfully applied to the determination of PAEs from carbonated soft drinks and the MSPE-GC/MS method developed in current study provides a new option for the detection of PAEs from carbonated soft drinks with complex matrices.

Background: Being exposed to cooking fumes, kitchen workers are occupationally at risk of multiple respiratory hazards. No conclusive evidence exists as to whether occupational exposure to these fumes is associated with acute and chronic pulmonary effects and symptoms of respiratory diseases. Objective: To quantify the exposure levels and evaluate possible chronic and acute pulmonary effects associated with exposure to cooking fumes. Methods: In this cross-sectional study, 60 kitchen workers exposed to cooking fumes and 60 unexposed employees were investigated. The prevalence of respiratory symptoms among these groups was determined through completion of a standard questionnaire. Pulmonary function parameters were also measured before and after participants' work shift. Moreover, air samples were collected and analyzed to quantify their aldehyde, particle, and volatile organic contents. Results: The mean airborne concentrations of formaldehyde, acetaldehyde, and acrolein was 0.45 (SD 0.41), 0.13 (0.1), and 1.56 (0.41) mg/m 3 , respectively. The mean atmospheric concentrations of PM 1 , PM 2.5 , PM 7 , PM 10 , and total volatile organic compounds (TVOCs) was 3.31 (2.6), 12.21 (5.9), 44.16 (16.6), 57 (21.55) μg/m 3 , and 1.31 (1.11) mg/m 3 , respectively. All respiratory symptoms were significantly (p

This study reports on the concentrations of airborne fungi in a waste paper and cardboard recycling factory (WPCRF) in Tehran, Iran. Sampling occurred every six days during winter at nine locations. The following order was observed in all processing units: Penicillium sp. (92 ± 6 CFU m−3) > Cladosporium sp. (74 ± 7 CFU m−3) > Aspergillus niger (19 ± 9 CFU m−3). In the processing units, the lifetime average daily dose ranged from 1.49 × 10−3 to 7.8 CFU (kg.d)−1 for the inhalation route and from 2.74 × 10−6 to 6.29 × 10−6 CFU (kg.d)−1 for the dermal route.

Background: Surveillance of current changes in the epidemiology of Invasive Fungal Diseases (IFDs) as an important component of the antifungal stewardship programs (ASP), requires careful regular monitoring, especially in high-risk settings such as oncology centers. This study aimed to examine Candida colonization status and corresponding current changes in children with malignancy during repeated admissions and also investigate the possible epidemiological shifts after the implementation of ASP. Methods: In this prospective observational study, all eligible patients younger than 18 years were recruited during 2016-2017 at Amir Medical Oncology Center (AMOC) in Shiraz, Iran. Totally, 136 patients were enrolled and 482 samples were collected from different sites (oral/nasal discharges, urine and stool). Weekly regular sampling was carried out during hospitalization. Candida colonization status and epidemiological changes were monitored during repeated admissions. Samples were cultivated on Sabouraud Dextrose agar medium and identified by Polymerase Chain Reaction -Restriction Fragment Length Polymorphism (PCR-RFLP). Results: Estimated Candida colonization incidence was 59.9% (82/136) in our patients. Candida colonization was found to be higher in oral cavity and rectum than that in nasal cavity. Among those long-term follow ups and repetitive hospitalizations, a significant number of patients exhibited changes in their colonization patterns (37.7%). Candida colonization did not reveal any significant relationship with age, sex, oncologic diseases and degree of neutropenia. C. albicans (72.0%) was found as the most common Candida species in colonized patients, followed by C. krusei, C. kefyr, C. glabrata and C. parapsilosis. Conclusion: Given the high incidence of Candida infections in children with cancers, close monitoring of epidemiologic changes is essential for judicious management, based on local surveillance data and improvement of overall quality of care in high risk patients. Key Words: Candida Albicans, Fungal Colonization, Pediatric Leukemia

This study reports a characterization of outdoor gaseous and particulate pollutants and their associated health effects in four different urban hotspots in Tehran, Iran during winter and summer. Buses, taxis, and cars are prominent sources of toxic pollutants in Tehran. There is a significant level of exposure to emissions from diesel buses in bus terminals, especially with boarding, disembarking, and waiting. Mean concentrations (μg/m3) in summer and winter, respectively, ranged from 10 to 20.67 and 17–21 for PM1, 52.50–79.19 and 58.33–85.33 for PM2.5, 64.50–102 and 78.83–125.83 for PM7, 130.17–204.67 and 157–231.67 for PM10, 261–409.50 and 305.83–458.83 for TSP, and 372.50–418.33 vs. 351.27–373.47 for CO2 (ppm). Particulate concentrations were higher in winter, especially the first three days of the week, assisted in part by the shallower mixing layer height as compared to summer. Mean hazard quotient (HQ) values for both PM2.5 and PM10 in both seasons for bus terminals in three scenarios ranged between 0.81 and 4.96, which exceeded reference levels (1

The multiple modes of SARS-CoV-2 transmission including airborne, droplet, contact, and fecal–oral transmissions that cause coronavirus disease 2019 (COVID-19) contribute to a public threat to the lives of people worldwide. Herein, different databases are reviewed to evaluate modes of transmission of SARS-CoV-2 and study the effects of negative pressure ventilation, air conditioning system, and related protection approaches of this virus. Droplet transmission was commonly reported to occur in particles with diameter >5 µm that can quickly settle gravitationally on surfaces (1–2 m). Instead, fine and ultrafine particles (airborne transmission) can stay suspended for an extended period of time (≥2 h) and be transported further, e.g., up to 8 m through simple diffusion and convection mechanisms. Droplet and airborne transmission of SARS-CoV-2 can be limited indoors with adequate ventilation of rooms, by routine disinfection of toilets, using negative pressure rooms, using face masks, and maintaining social distancing. Other preventive measures recommended include increasing the number of screening tests of suspected carriers of SARS-CoV-2, reducing the number of persons in a room to minimize sharing indoor air, and monitoring people’s temperature before accessing a building. The work reviews a body of literature supporting the transmission of SARS-CoV-2 through air, causing COVID-19 disease, which requires coordinated worldwide strategies.

This study aimed to determine the methane production's potential from municipal solid wastes based on two setups; firstly, based on waste composition and secondly based on using the landfill gas em...

Urbanization generates increased amounts of solid wastes in cities and as a consequence leads to high air pollution levels. As a result of these trends, the subject of air quality management for sustainable concept of cities has received increasing attention. This work characterized volatile organic compound (VOC) emissions and health effects at different processing stages in a recycling facility for waste paper and cardboard. The highest total VOC levels were observed in the conveyor belt line one (5.23 ± 0.33 mg/m3), followed by a baling machine (1.38 ± 0.07 mg/m3), conveyor belt line two (1.34 ± 0.08 mg/m3), tipping floor line one (1.22 ± 0.07 mg/m3), and manual separation line one (1.20 ± 0.06 mg/m3). Hence, exposure to VOCs lead to high health risks in this PCSWRF, especially at the manual separation stage (HQ = 2.7–3 and lifetime cancer risks (LTCRs) = 1.11 × 10−4 - 1.03 × 10−4), and strategies such as adjustment of the factory to enclose the conveyors, designing proper ventilation and air conditioning systems, minimization of VOC-contaminated waste generation (pre-treatment), and using personal protective equipment should be considered to eliminate pollutants and to protect workers from the non-carcinogenic and carcinogenic effects.

This study investigated the concentrations of suspended particulate matter £ 10 µm in diameter (PM10) and their heavy metal content, including cadmium, lead, chromium, zinc, nickel, aluminum, and iron, in ambient air in the Middle East: Shiraz, Iran. The Crystal Ball 7.3 software package was used to assess carcinogenic and non-carcinogenic health effects due to heavy metal exposure. The mean concentrations of heavy metals increased in the following order: Fe > Al > Zn > Pb > Cr > Ni > Cd. Meanwhile, the average concentrations of PM10 decreased during the same time frame. When comparing PM10 on various days of the week in Iran, including holidays (Thursday and Friday), two days after holidays (Saturday and Sunday), and other days (Monday, Tuesday and Wednesday), the concentrations were higher two days after the holidays as compared to other days of the week (p

In this current study, the contents of heavy metals including Pb, As, Cr, Cd, Zn, Cu, and Mn in imported rice bran oil in Iran were investigated with microwave digestion method based on an inductively coupled plasma optical emission spectrometry system (ICP-OES). The concentrations range of Pb, Cr, Cd, As, Zn, and Cu in rice bran oil samples were measured as 0.066–0.30, 0.008–0.014, 0.005–0.01, 0.047–0.01, 0.025–0.74 and 0.01–0.096 μg/g, respectively. A significant difference (p-value

This study was conducted in order to assess the exposure to bacterial and fungal bioaerosols in the air of waterpipe cafes (AWPCs), in the hose of waterpipe (HWP), and in the water bowl of the waterpipe (WBWP) and to investigate the factors influence increasing the contamination levels in waterpipe cafes in Ardabil. From all the 50 cafes studied, the samples were taken from air and from water contained in water bowl and hose for bacterial and fungal analyses. The results demonstrated that the mean numbers of bacteria and fungi in the indoor air of cafe, hose, and water bowl were 33.90 ± 14.86 and 25.24 ± 1.99 CFU/m3, 72.16 ± 29.55 and 72.78 ± 42.45 CFU/plate, 53.7 ± 25.46 and 25.26 ± 13.94 CFU/ml, respectively. The predominant bacterial genera in waterpipe cafes were Pseudomonas and Bacillus in air, Staphylococcus and Pseudomonas in the hose, and Staphylococcus and Pseudomonas in the water bowl, respectively. The predominant fungal species in waterpipe cafes were Penicillium and Cladosporium in air, yeast and Fusarium in the hose, and Paecilomyces and yeast in the water bowl, respectively. The results of statistical analysis showed that there was a significant relationship between the mean concentrations of bacterial aerosol and qualitative variables such as type of heating system, materials of wall and ceiling, traditional restaurants, interior supermarkets, moisturized walls, the number of people, area of cafes, and temperature. But there was no significant relationship between these variables and the mean concentration of fungal aerosols. The results also showed that the levels of bioaerosols were high in the air, hose, and water bowl of the waterpipe. Therefore, cafes can be a potential source for the transmission of pathogenic agents and increase the risk of respiratory diseases among waterpipe smoking individuals.

This study characterized spatio-temporal variations in the concentration of benzene, toluene, ethylbenzene, and xylene (BTEX) compounds in the vicinity of gas and compressed natural gas (CNG) stations in Tehran, Iran. Health risk assessment (HRA) was computed using Monte Carlo simulations (MCS) for evaluating inhalation lifetime cancer risk (LTCR), the hazard quotient (HQ), and sensitivity analysis (SA) for BTEX exposure in different age groups (birth to 0.05). Factors promoting BTEX formation in the study region were fuel evaporation and gas/CNG station emissions. The LTCRs for the target compounds in the winter for different age groups and distances from the center of stations was limited to 2.11 × 10−4 to 1.82 × 10−3 and 2.30 × 10−4 to 2.01 × 10−3, respectively, which exceeded proposed values by U.S. EPA. Moreover, the HQs for BTEX for three age groups and distances were limited to between 2.89 × 10−5 and 9.33 × 10−2, which were lower than the acceptable limit (HQs

Bioaerosols produced from Wastewater Treatment Plants (WWTPs) can pose health risks to plant workers and nearby inhabitants. There is a gap in air quality data for WWTPs in developing countries. The present study aimed to measure airborne bacterial and fungal concentrations in a WWTP in southwestern Iran between September 2015 and May 2016. Active sampling was conducted around operational units, and a total of 600 bacterial and fungal samples were collected. Spatial and seasonal comparisons were made. The highest average concentrations of culturable bacterial aerosol at seasonally dependent locations were, in decreasing order, 2581 ± 401 and 1952 ± 390 CFU m(−3) for the selector and aeration tanks, respectively, in autumn; 1363 ± 299 CFU m(−3) for the aeration tank in winter; and 1738 ± 350 CFU m(−3) for the screw pump in spring. Furthermore, the predominant genera of airborne fungi isolated from the air of the WWTP in all three seasons were Cephalotrichum spp., Alternaria spp., Penicillium spp., Monilia spp., and Aspergillus spp. The results of this work emphasize the necessity of controlling WWTP workers’ exposure to bioaerosols when bacteria and fungi become aerosolized during aeration.

Operating rooms (ORs) in hospitals are sensitive wards because patients can get infections. This work aimed to characterize the type and concentration of bioaerosols in nine ORs of an educational hospital before and after sterilization and disinfection. During 2017, fungal samples were incubated at 25–28 °C for 3–7 days and bacterial samples at 37 °C for 24–48 h. The study results showed that the concentrations of fungi before cleaning procedures (for both of disinfection and sterilization) were limited from 4.83 to 18.40 CFU/m3 and after cleaning procedures ranged from 1.90 to 8.90 CFU/m3. In addition, the concentrations of bacteria before cleaning procedures were limited 14.65–167.40 CFU/m3 and after cleaning procedures ranged from 9.50 to 38.40 CFU/m3. The difference between the mean concentrations of airborne bioaerosols before and after sterilization was significantly different than the suggested value of 30 CFU/m3 (p ≤ 0.05). The bacterial concentration was higher than the recommended value (30 CFU/m3) in 41% of the ORs. The main fungal species identified in the indoor air of ORs (before vs. after sterilization) were A. fumigatus (25.6 vs. 18.3%), A. Niger (11.6 vs. 5.8%), Penicillium spp. (5.5 vs. 3.3%), Alternaria spp. (2.8 vs. 0.7%), Fusarium spp. (9.7 vs. 3.7%), Mucor spp. (15 vs. 12.7%), Cephalotrichum spp. (1.7 vs. 0.8%), A. Flavus (24.6 vs. 18.5%), Cladosporium spp. (2.6 vs. 0.8%), and Trichoderma spp. (0 vs. 0.9%). The growth of biological species even after sterilization and disinfection likely resulted from factors including poor ventilation, sweeping of OR floors, inadequate HVAC filtration, high humidity, and also lack of optimum management of infectious waste after surgery. Designing well-constructed ventilation and air-conditioning systems, replacing HEPA filters, implementing more stringent, frequent, and comprehensive disinfection procedures, and controlling temperature and humidity can help decrease bioaerosols in ORs.

Concentrations of benzene, toluene, ethylbenzene, and xylene (BTEX) were investigated in indoor air quality of 50 beauty salons in Ardabil, Iran (2017). Ten liters of air samples were collected from each salons regarding the recommended method and analyzed by GC-FID for BTEX concentration. Also, structural and operational conditions of the salons were studied with a self-designed questioner. The results of this study show that the mean concentration of benzene (32.40 ± 26.38) higher than the recommended levels by Health Canada, ANSES and HKSAR. Among the BTEX, ethylbenzene (62.38 ± 32.37) has the most concentrations in the salons. Subsequently, the cancer risk values in different age groups of birth to6, 6 to21, and 21 to81 for benzene (1.83 × 10

This work summarizes characteristics of acetaldehyde and formaldehyde in autumn 2018 in the ambient air of a major bus terminal in Tehran, Iran. The average (±standard deviation) concentration of formaldehyde/acetaldehyde was 109.99 ± 23.47/85.4 ± 17.17 μg m−3. Major sources of these species were traffic emissions, photochemical processes, and biogenic sources (e.g., deciduous-coniferous tree). The average inhalation lifetime cancer risk (ILTCR) values based on IRIS for both aldehydes were between 7.07 × 10-5 and 5.09 × 10-4, which surpass suggested EPA magnitudes. The mean ILTCR values based on the office of environmental health hazard assessment for these species ranged from 1.21 × 10-4 to 1.02 × 10-3, which exceed suggested values by EPA for eleven different age groups. Hazard quotient (HQ) values of formaldehyde were between 7.27 ± 1.61 to 1.34 ± 0.29, while those of acetaldehyde were between 6.68 ± 1.49 and 1.58 ± 0.355. Hence, the ILTCRs and HQs of these toxic species were higher than 1 × 10−6 and one, respectively, which is not at "an acceptable risk for humans". The results of the current work have relevance to the health of the general public close to ‘hot-spots’ like the study region where a large number of people are in contact with carcinogenic pollutants.

This study reports a characterization of indoor polycyclic aromatic hydrocarbons (PAHs) associated with dust (dust-PAHs) in household evaporative coolers and their associated health effects. Extensive analysis showed that the indoor dust-PAHs stemmed mostly from pyrogenic sources (vehicular emissions) with mean total concentrations limited between 131 and 429 ng g−1. The distribution pattern of PAHs based on number of rings exhibited the following order of decreasing relative abundance: 4 > 3 > 5 > 6 > 2 rings. Results indicate that the mutagenicity of dust-PAHs exceeded their carcinogenicity, but that the potential carcinogenic effects are still significant. The mean lifetime cancer risk for different age groups for three pathways based on Model 2 (dermal (1.39 × 10−1 to 1.91 × 10−2), ingestion (2.13 × 10−3 to 8.08 × 10−3) and inhalation (1.62 × 10−7 to 4.06 × 10−7)) was 7.4–146 times higher than values predicted by Model 1 (dermal (5.13 × 10−5 to 3.03 × 10−3), ingestion (9.34 × 10−5 to 1.31 × 10−3) and inhalation (7.13 × 10−20 to 1.68 × 10−20)). Hence, exposure to dust-PAHs in household evaporative coolers lead to high risk, especially for children (less than 11 years) (HQ = 2.71 × 10−20 to 54.8 and LTCRs = 7.13 × 10−20 to 1.39 × 10−1). Strategies should be considered to eliminate such pollutants to protect people, especially children, from the non-carcinogenic and carcinogenic effects by changing household evaporative coolers with other cooling systems.

The determination of trace levels of various compounds is very important for the accurate assessment of occupational exposure hazards. Recently, due to shortcomings of conventional methods, the use of microextraction techniques to sample and analyze compounds in various matrices has increased significantly. The shortcomings of conventional techniques include poor sensitivity, the consumption and disposal of significant amounts of toxic solvents, complexity, and the use of long and multiple-step sample preparation protocols. In contrast, microextraction techniques are advantageous because they utilize single-step sampling and solvent-free preparation and have the potential for automation and reduced analysis times. As shown in the literature, microextraction techniques include solid-phase microextraction (SPME), needle trap device (NTD), and liquid-phase microextraction (LPME), which have all shown increased sensitivity, extraction efficiency, and selectivity than conventional methods. This review focuses on microextraction techniques used for sampling and determination of various compounds in an occupational environment. In this review, the application of microextraction techniques in occupational exposure assessment is examined, along with a discussion of their future prospects.

Background Discharge of heavy metals such as hexavalent chromium (Cr (VI)) and nickel (Ni (II)) into aquatic ecosystems is a matter of concern in wastewater treatment due to their harmful effects on humans. In this paper, removal of Cr (VI) and Ni (II) ions from aqueous solution was investigated using an amino-functionalized magnetic Nano-adsorbent (Fe3O4-NH2). Methods An amino-functionalized magnetic Nano-adsorbent (Fe3O4-NH2) was synthesized by compositing Fe3O4 with 1, 6-hexanediamine for removal of Cr (VI) and Ni (II) ions from aqueous solution. The adsorbent was characterized by Scanning Electron Microscope (SEM), Transmission Electron Microscopy (TEM), powder X-Ray Diffraction (XRD), and Vibrating Sample Magnetometry (VSM). Also, the effects of various operational parameters were studied. Results According to our finding, Fe3O4-NH2 could be simply separated from aqueous solution with an external magnetic field at 30 s. The experimental data for the adsorption of Cr (VI) and Ni (II) ions revealed that the process followed the Langmuir isotherm and the maximum adsorption capacity was 232.51 mg g−1 for Cr (VI) at pH = 3 and 222.12 mg g−1 and for Ni(II) at pH = 6 at 298 °K. Besides, the kinetic data indicated that the results fitted with the pseudo-second-order model (R2: 0.9871 and 0.9947 % for Cr (VI) and Ni (II), respectively. The results of thermodynamic study indicated that: standard free energy changes (ΔGɵ), standard enthalpy change (ΔHɵ), and standard entropy change (ΔSɵ) were respectively −3.28, 137.1, and 26.91 kJ mol−1 for Cr (VI) and −6.8433, 116.7, and 31.02 kJ mol−1 for Ni (II). The adsorption/desorption cycles of Fe3O4-NH2 indicated that it could be used for five times. Conclusions The selected metals’ sorption was achieved mainly via electrostatic attraction and coordination interactions. In fact, Fe3O4-NH2 could be removed more than 96 % for both Cr (VI) and Ni (II) ions from aqueous solution and actual wastewater.

This study reports a spatiotemporal characterization of toluene, benzene, ethylbenzene, and xylenes concentrations (BTEX) in an urban hot spot in Iran, specifically at an bus terminal region in Shiraz. Sampling was carried out according to NIOSH Compendium Method 1501. The inverse distance weighting (IDW) method was applied for spatial mapping. The Monte Carlo simulation technique was applied to evaluate carcinogenic and non-carcinogenic risk owing to BTEX exposure. The highest average BTEX concentrations were observed for benzene in the morning (at 7:00–9:00A.M. local time) (26.15±17.65μg/m3) and evening (at 6:00–8:00P.M. local time) (34.44±15.63μg/m3). The benzene to toluene ratios in the morning and evening were 2.02 and 3.07, respectively. The main sources of BTEX were gas stations and a municipal solid waste transfer station. The inhalation lifetime cancer risk (LTCR) for benzene in the morning and evening were 1.96×10−4 and 2.49×10−4, respectively, which exceeds the recommended value by US EPA and WHO. The hazard quotient (HQ) of all these pollutants was less than 1. The results of this work have implications for public health near ‘hot spots’ such as IKBT where large populations are exposed to carcinogenic emissions.