Non-carcinogenic and cumulative risk assessment of exposure of kitchen workers in restaurants and local residents in the vicinity of polycyclic aromatic hydrocarbons.

Polycyclic aromatic hydrocarbons (PAHs) are often formed when organic substances do not burn completely. This study evaluates the non-carcinogenic and cumulative risks associated with PAHs levels by testing blood and urine samples in kitchen workers and residents near restaurants in Shiraz, Iran. Metabolites of PAH in the urine samples as well as clinical parameters in the blood samples were measured. The non-carcinogenic and cumulative risk assessments from exposure of the study groups to PAH metabolites were also evaluated. The highest average concentrations of PAH metabolites were related to kitchen workers (2126.7 ng/g creatinine (ng/g cr)). The metabolites of 1-Hydroxypyrene (1-OHP) and 9-Phenanthrene (9-OHPhe) had the highest and lowest mean concentrations, respectively. A direct correlation was observed between the levels of PAH metabolites with malondialdehyde (MDA) and total antioxidation capacity (TAC) levels (p < 0.05). Hazard Index (HIi) was obtained less than one (HIi < 1), indicating low-risk negative health impacts on the target groups. Nevertheless, conducting more studies to determine the health status of these people is quite evident.

Modeling and optimization approach for phytoremediation of formaldehyde from polluted indoor air by Nephrolepis obliterata plant.

This study aimed to model the removal of formaldehyde as an indoor air pollutant by Nephrolepis obliterata (R.Br.) J.Sm. plant using response surface methodology (RSM) and artificial neural network (ANN) models, and optimization of the models by particle swarm optimization algorithm (PSO). The data obtained in pilot-scale experiments under a controlled environment were used in this study. The effects of parameters on the removal efficiency such as formaldehyde concentration, relative humidity, light intensity, and leaf surface area were empirically investigated and considered as model parameters. The results of the RSM model, with power transformation, were in meaningful compromise with the experiments. A multilayer perceptron (MLP) neural network was also designed, and the mean of squared error (MSE), mean absolute error (MAE), and R2 were used to evaluate the network. Several training algorithms were assessed and the best one, the Levenberg Marquardt (LM), was selected. The PSO algorithm proved that the highest removal efficiency of formaldehyde was obtained in the presence of light, maximum leaf surface area and relative humidity, and at the lowest inlet concentration. The empirical system breakthrough occurred at 15 mg/m3 of formaldehyde, and the maximum elimination capacity was about 0.96 mg per m2 of leaves. The findings indicated that the ANN model predicted the removal efficiency more accurately compared to the RSM model.

Health risk assessment of polycyclic aromatic hydrocarbons in individuals living near restaurants: a cross-sectional study in Shiraz, Iran.

Polycyclic aromatic hydrocarbons (PAHs) are persistent toxic substances that have ubiquitous presence in water, air, soil, and sediment environments, posing serious environmental risks. The present study aimed to investigate the concentrations of urinary PAHs and their health effects in individuals living near restaurants via a health risk assessment analysis. This cross-sectional study was performed on 57 people living near restaurants and 30 individuals as the control group. Five urinary metabolites of PAHs were monitored. In order to evaluate the effects of the urinary metabolites of PAHs on Malondialdehyde (MDA) concentration, Total Anti-oxidation Capacity (TAC) in urine samples, and C-Reactive Protein (CRP) in serum samples, regression model was used by considering the effects of the possible confounding factors. Non-carcinogenic health risk was calculated, as well. The median concentration of urinary PAHs was 1196.70 and 627.54 ng/g creatinine in the people living near restaurants and the control group, respectively. Among the metabolites, the lowest and highest mean concentrations were related to 9-OHPhe and 1-OHP, respectively in the two study groups. Moreover, PAHs were significantly associated with MDA level and TAC (p < 0.05). Hazard Quotient (HQ) and Hazard Index (HI) were less than 1. Long-term studies are required to determine the actual health effects by identifying the sources of PAHs emission and to find ways to decrease the production of these compounds.

Exposure to polycyclic aromatic hydrocarbon-induced oxidative stress in Shiraz, Iran: urinary levels, health risk assessment and mediation effect of MDA on the risk of metabolic syndromes.

PURPOSE: Polycyclic Aromatic Hydrocarbons (PAHs) have been identified as carcinogenic and endocrine disrupter compounds that cause Metabolic Syndrome (MetS). Oxidative stress can lead to carcinogenesis and MetS in exposed people. Therefore, the relationship between urinary metabolite of PAH (OH-PAHs) level and the oxidative stress biomarker (Malondialdehyde) effect as the mediator in increasing the risk of MetS due to PAH exposure and risk assessment was investigated in Shiraz, Iran. METHODS: The first morning void urinary and blood samples were obtained from participants and analyzed. Physical examinations and anthropometric measurements were performed on the day of sampling. An automatic biochemistry analyzer was used to measure the blood cells. The participants' socio-demographic information was gathered using a questionnaire and direct interviews with participants. RESULTS: The MetS prevalence was 26%. Malondialdehyde could act as a mediator between exposure to 1-HydroxyPyrene and increase in fast blood sugar, exposure to 2-HydroxyNaphthalene and increase in systolic blood pressure and exposure to 2-HydroxyFluorene and increase in SBP. Hazard quotients varied from 0.009 to 14.92 in women, and from 0.005 to 8.43 for Fluorene and Naphthalene in men, respectively. The Hazard Indexes were greater than one meaning that the non-cancer health risk related to the PAH exposure could be identified in the participants. CONCLUSION: Although oxidative stress has been suggested to lead to MetS and the high HI levels obtained in the current study, future researches are essential to achieve more reliable findings and monitoring the environmental influencing factors in PAH exposure.

Determination of chloroform concentration and human exposure assessment in the swimming pool.

This cross-sectional study aimed to examine the concentration of the by-products of chlorination in the swimming pool and estimate human health risk for the swimmers of Shiraz University of Medical Sciences. In this study, the chloroform concentrations of 16 samples were measured using Gas Chromatography (GC). All the measured concentrations were less than the allowed amount announced by the World Health Organization (WHO). The results of the cancer risk (CR) and hazard index (HI) showed that the major exposure routes were found to be dermal during swimming and the 95 percentile of estimated CR and HI for the male group were 1.38 × 10-10 and 1.82 × 10-5 respectively, which is higher than the values of 5.48 × 10-10 and 2.25 × 10-5 respectively, for the women group. Sensitivity analyses indicated that the swimming exposure time (ET), and chloroform concentration were the most relevant variables in the health risk model. Therefore, knowledge about the sources of micro-pollutants in swimming pools might help promote the health methods of the pool environment.

Health risks of inhalation exposure to BTEX in a municipal wastewater treatment plant in Middle East city: Shiraz, Iran.

Benzene, toluene, ethylbenzene, and xylene, known as BTEX, adversely affect human health. This study aimed to measure BTEX concentration and assess the health risk through inhalation exposure to these compounds in a municipal wastewater treatment plant. The ambient air samples were collected using the active sampling method in summer and winter. Sampling sites were close to wastewater treatment units, including bar screen & grit chamber (Site-1), aeration tank & secondary clarifiers (Site-2), anaerobic sludge digester (Site-3), and office & control building (Site-4). Results indicate that the mean levels of benzene and toluene in winter were higher than in summer. The levels of benzene and toluene were below the occupational exposure levels of the American Conference of Governmental Industrial Hygienists (ACGIH) and Occupational Safety and Health Administration (OSHA). The carcinogenic risk (CR) and hazard quotient (HQ) were assessed using the United States Environmental Protection Agency (U.S.EPA) method, and Monte Carlo simulation (MCS) was applied to quantify the uncertainty and sensitivity analysis. The CRs for all sampling sites were below the U.S.EPA threshold limit (1.0 × 10-4). The HQ values for benzene nearby Site-2 were above 1.0, indicating inhalation exposure could pose a health hazard. Besides, the HQ results for exposure to toluene in all sampling sites were less than 1.0. The sensitivity analysis had shown that the risk determinant for carcinogenic and non-carcinogenic risk was exposure time, followed by concentration.

Health risk assessment of exposure to atrazine in the soil of Shiraz farmlands, Iran.

Atrazine-contaminated soils can pose a carcinogenic and non-carcinogenic health risk through different routes for exposed people. This study aimed to assess the health risk of exposure to atrazine-contaminated soils through direct ingestion and dermal contact in farmlands nearby Shiraz. Atrazine concentration was measured in 22 selected sites using grid sampling. The carcinogenic and non-cancer risks associated with dermal and ingestion exposure in children and adults were estimated. The lowest and highest atrazine concentrations were in S1 (0.015 mg/kg soil) and S22 (0.55 mg/kg soil). Hazard Index (HI)1 values ranged from 0.007 to 0.25 for children, and the values ranged from 0.0008 to 0.03 for adults. The mean cancer risk for children and adults was 6.01 × 10-4 and 7.40 × 10-5, respectively. The HI value was less than 1 for all sampling sites, indicating that exposure to atrazine does not threaten children and adults. However, the cancer risk exceeds the United States Environmental Protection Agency (US.EPA)2 threshold risk limit (10-6 to 10-4) in all sampling sites. Therefore, it is recommended that children should avoid playing on atrazine-contaminated farms or soils near anywhere atrazine may have been used.

Photocatalytic degradation of 2,4-dichlorophenoxyacetic acid from aqueous solutions by Ag3PO4/TiO2 nanoparticles under visible light: kinetic and thermodynamic studies.

Between the countless chemical substances applied in agriculture, 2,4-dichlorophenoxyacetic acid (2,4-D) herbicide is considered as a toxic and carcinogenic pollutant which is difficult to remove from water due to its biological and chemical stability and high solubility. The goal of this study was photocatalytic degradation of 2,4-D, using Ag3PO4/TiO2 nanoparticles under visible light. The Ag3PO4/TiO2 nanoparticles were characterized using XRD, FESEM and EDS analysis to investigate its crystal structure and elemental compounds. The effect of operating parameters such as pH, contact time, catalyst dose, and initial concentration of herbicide on the efficiency of the process was studied. Increasing the pH and initial concentration of herbicide led to the reduction of the efficiency of removing the herbicide, while increasing contact time and catalyst dose increased the efficiency. The best result (98.4% removal efficiency) was achieved at pH = 3, 1 g/L catalyst dose, 60 min contact time, and 10 mg/L initial concentration of 2,4-D. According to the results, 2,4-D removal efficiency with Ag3PO4/TiO2 photocatalyst reached 96.1% from 98.4% after 5 cycles of reaction. The pseudo-first-order kinetics was the best fit for the 2,4-D degradation by Ag3PO4/TiO2 with correlation coefficients (R2 = 0.9945). The results demonstrated that the photocatalytic process using Ag3PO4/TiO2 nanoparticles in the presence of visible light had a relatively good efficiency in removing 2,4-D. Moreover, Ag3PO4/TiO2 can be used as a reusable photocatalyst for the degradation of such toxins from polluted water and wastewater.

Assessing BTEX exposure among workers of the second largest natural gas reserve in the world: a biomonitoring approach.

Urinary benzene, toluene, ethylbenzene, and xylenes (BTEX) can be used as a reliable biomarker of exposure to these pollutants. This cross-sectional study aimed to employ biomonitoring to assess BTEX exposure among South Pars Gas Field (SPGF) workers in Assaluyeh, Iran. Forty employees who were working on the site were recruited as the case group. Besides, 31 administrative employees were recruited as the control group. Pre-shift and post-shift spot urine samples were collected from the subjects in the case group, while the subjects in the control group provided mid-morning urine samples. Overall, 111 urine samples, including 80 samples from the case group and 31 samples from the controls, were collected. Gas chromatography-mass spectrometry (GC/MS) was used to determine the urinary levels of BTEX compounds. The median urinary levels of benzene, toluene, ethylbenzene, m,p-xylene, and o-xylene in the post-shift samples of the exposed group were 1.24, 2.28, 0.5, 1.32, and 1.5 µg/l, respectively. Significant differences were observed in urinary BTEX levels among smokers and non-smokers in both studied groups (p < 0.05). Accordingly, the median urinary BTEX concentrations in smokers were 2 to 6.5 times higher than the corresponding values in non-smoker subjects. Smoking status was the only predictor of the urinary BTEX concentration. Our findings revealed that refinery workers are exposed to significant levels of BTEX compounds. Considering the health risks associated with BTEX exposure for refinery workers, implementation of suitable control strategies, such as using appropriate personal protective equipment and improving on-site ventilation systems, are recommended reducing their exposure to BTEX via the inhalation.

Investigating the relationship between synergistic effects and diversity of four widely used agricultural pesticides by using bacterial species in liquid culture medium.

Interactive effects of mixtures of pesticides on bacteria are rarely investigated. The aim of this study was to investigate the cumulative, synergistic, and antagonistic effects of four widely used agricultural pesticides including deltamethrin, diazinon, chlorpyrifos, and 2,4-dichlorophenoxyacetic acid (2,4-D) on Pseudomonas, Aeromonas, and Bacillus bacteria. The reduction of alamar blue, as an indicator of bacterial activity, was measured using a spectrophotometer at 600-nm wavelength. Data were analyzed using SPSS 24.0 software. The binary mixtures of pesticides had mainly antagonistic and additive effects, but quadruple mixtures of pesticides had synergistic effects on all of the three bacterial species. In the mixtures of pesticides, increasing the number of compounds leads to more synergistic effects.

Changing face of Candida colonization pattern in pediatric patients with hematological malignancy during repeated hospitalizations, results of a prospective observational study (2016-2017) in shiraz, Iran.

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.

Direct red 81 adsorption on iron filings from aqueous solutions; kinetic and isotherm studies.

Direct Red 81 (DR-81) dye with a very high water solubility is widely used in many industries particularly textile industries. This study aimed to evaluate the practicability of using iron filings for the adsorption of DR-81 dye from the aqueous solutions. The effects of pH, adsorbent dose, initial DR-81 dye concentration, and adsorption time on adsorption process were also evaluated. The maximum of adsorption efficiency of DR-81 dye achieved in the optimum pH: 3, adsorbent dose: 2.5 g/L, contact time: 30 min, and initial dye concentration: 50 mg/L. The dye adsorption efficiency is increased by increasing the adsorbent dose and adsorption time. The kinetic and isotherm studies indicated that the adsorption process obeys a pseudo-first-order and Langmuir isotherm models. The experimental studies indicated that iron filings had the potential to act as an alternative adsorbent to remove the DR-81 dye from an aqueous solution.

Concentration and type of bioaerosols before and after conventional disinfection and sterilization procedures inside hospital operating rooms.

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.

Characteristics and health effects of BTEX in a hot spot for urban pollution.

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 ±â€¯17.65 µg/m3) and evening (at 6:00-8:00 P.M. local time) (34.44 ±â€¯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.

Characterisation and potential source identification of polycyclic aromatic hydrocarbons in atmospheric particles (PM10) from urban and suburban residential areas in Shiraz, Iran.

Polycyclic aromatic hydrocarbons (PAHs) are a generally hazardous class of organic compounds that are identified as toxic, carcinogenic, mutagenic, and teratogenic, and are considered to be a concern for human health because of their potential for causing adverse health effects. The present study aims to determine the atmospheric concentration and potential sources of particulate-bound PAHs in urban and suburban atmospheric particulate matter (PM10) in Shiraz, Iran. Ambient air samples were collected from urban and suburban areas using a SKC sampling pump equipped with a size-selective air intake during the spring of 2015. The mean PM10 concentration at the urban station (62.73 ± 23.38 µg m-3) was higher than that at the suburban station (60.88 ± 31.03 µg m-3). The mean (±SD) concentrations of the 16 total PAHs in the particulate phase were 19.28 ± 7.48 ng m-3and 17.80 ± 9.17 ng m-3 at the urban and suburban stations, respectively. Among different types of PAHs, phenanthrene had the highest concentration in both stations. Various diagnostic ratios have been suggested, which were used in this study for identification of PAHs' sources. The results of these diagnostics showed that in Shiraz, the most dominant sources of PAHs were traffic emissions, especially vehicle emissions and petroleum automobiles emissions.

The effects of air pollutants on the mortality rate of lung cancer and leukemia.

World Health Organization classifies air pollution as the first cause of human cancer. The present study investigated impact of air pollutants on the mortality rates of lung cancer and leukemia in Shiraz, one of the largests cities of Iran. This cross­sectional (longitudinal) study was carried out in Shiraz. Data on six main pollutants, CO, SO2, O3, NO2, PM10 and PM2.5, were collected from Fars Environmental Protection Agency for 3,001 days starting from 1 January, 2005. Also, measures of climatic factors (temperature, humidity, and air pressure) were obtained from Shiraz Meteorological Organization. Finally, data related to number of deaths due to lung and blood cancers (leukemia) were gathered from Shiraz University Hospital. Relationship between variations of pollutant concentrations and cancers in lung and blood was investigated using statistical software R and MiniTab to perform time series analysis. Results of the present study revealed that the mortality rate of leukemia had a direct significant correlation with concentrations of nitrogen dioxide and carbon monoxide in the air (P<0.05). Therefore, special attention should be paid to sources of these pollutants and we need better management to decrease air pollutant concentrations through, e.g., using clean energy respect to fossil fuels, better management of urban traffic planning, and the improvement of public transport service and car sharing.

Biological monitoring of urinary 1-hydroxypyrene by PAHs exposure among primary school students in Shiraz, Iran.

AIM OF STUDY: This research aimed to estimate PAHs exposure in primary school students and determine its association with other PAHs-related factors. MATERIALS AND METHODS: In total, 120 male primary school students (9-12 years old) were randomly selected from urban and suburban areas in Shiraz. The parents were required to complete a questionnaire including information about second-hand smoke exposure, residential traffic density, daily diet, and walking or being driven to school. High-performance liquid chromatography with fluorescence detector was also used to analyze urinary 1-OHP. t test, ANOVA (with Ducan's post hoc test), and multiple regression analysis were used to analyze the relationship between quantitative and qualitative variables and urinary 1-OHP concentration. RESULTS: The range and geometric mean of the creatinine-corrected 1-OHP levels were 120-6950 and 1460 ng/g creatinine, respectively. Besides, 1-OHP levels were higher among the children with smoker parents compared to those having non-smoker parents. The results also revealed a correlation between the duration of exposure to second-hand tobacco smoke and 1-OHP concentration. This correlation was also observed for daily uptake of smoked or grilled foods. However, traffic congestion did not have any significant effects on 1-OHP levels. PAHs are commonly present in Iranian diet. As a result, the weekly intake of dietary PAHs was the most effective predictor of PAHs exposure in the study population. CONCLUSION: Due to adverse health effects of PAHs on humans, especially children, more extensive studies are required to identify the sources that contribute to environmental PAHs exposure.

The effects of Fenton process on the removal of petroleum hydrocarbons from oily sludge in Shiraz oil refinery, Iran.

BACKGROUND: Due to the high concentrations of total petroleum hydrocarbons (TPH) in oily sludge and their environmental hazards, the concern regarding their effects on health and the environment has increased. The main objective of this research was focused on evaluating the feasibility of using Fenton process in removing TPH in oily sludge from Shiraz oil refinery, Southern Iran. RESULTS: To determine optimum conditions, four different parameters were assessed at four different levels using Taguchi method. According to data, the optimum conditions were as follows: the reaction time of 1 hour, H2O2 to sample mass ratio of 15, H2O2 to Fe (II) molar ratio of 10 and pH of 5. The maximum TPH reduction rate was 36.47%. Because of the semi-solid nature of the sample and the hydroxyl radicals mainly generated in the aqueous solution, TPH reduction rate greatly improved by adding water. Ultimately, by adding 40 ml water per gram of the oily sludge under optimized conditions, the reduction rate of 73.07% was achieved. CONCLUSIONS: The results demonstrated that this method can be used as a pre-treatment method for the oily sludge. Moreover, a complementary treatment is necessary to reach the standard limit.