Iranian Journal of health, safety andenvironment

1091-1098

Authors: Shima Rezaei, Hooshyar Hossini, Majid Hashemi

Chlorophenols as priority pollutants are toxic. These acidic organic compounds cause digestive disorders, liver damage, and cancers. The aim of this study is Ortho- chlorophenol removal using zero-valent iron nanoparticles modified clay. In this experimental study, the clay soil was sampled from the mountains of Shah Murad, Rafsanjan, Iran. Then it was treated with hydrochloric acid. In the next step, the clay was modified with ferrous sulfate in the presence of the N2 gas to prepare magnetic clay. Then, the prepared adsorbent was used to remove o-chlorophenol as a function of pH, adsorbent dose and contact time. In addition, adsorption isotherms and kinetics were determined. The findings of the present study showed that the removal efficiency obtained by the iron nanoparticles carrying clay was higher than that of the raw clay. The highest removal efficiency (91.3 %.) was obtained for pH 4. The o-CP removal efficiency by the modified clay increased from 35.9 to 82.7 as the adsorbent dosage is increased from 0.05 to 1 g after 120min contact time. The Langmuir isotherm model and the second-order kinetic model provided the best fit to the experimental data compared to other studied models. The results showed that the modified adsorbent could be used an effective and readily available low-cost adsorbent for the removal of chlorophenols in industrial applications.

1107-1104

Authors: Mohammad Amin Mououdi, Seyed Nouraddin Mousavinasab, Jafar Akbari

This study assessed the status of health, safety and environment (HSE) in all public schools (n=188) in Iran using a new tool (HSE-S) based on audit system. The first part of HSE-S tool was about general specifications and environment conditions. The second consists of the physical conditions and school management. The HSE-S was validated using CVI and CVR, Cronbach's alpha and Kappa coefficient. The CVI, CVR, Cronbach's alpha coefficient and Kappa index were 0.75,> 0.7, 0.99 and 0.736 respectively. Ten schools were ranked as one-star, 149 as two-star and 29 as three-star. The top priorities for achieving an acceptable HSE status in schools were establishing a HSE unit, improving ergonomics and having a risk management system in each school. The HSE-S is an effective tool to evaluate and promote health, safety and environment in schools. Its application can help in implementing the “health promoting school” program of WHO.

1122-1127

Authors: Javid Manzoor, Manoj Sharma

We investigated general working conditions in the hospitals and nursing homes in Gwalior and assessed the health risk factors of employs in these hospitals April 2016 to August 2016. Sound Intensity Level (SIL) and light intensity was measured with sound and lux meter respectively. The temperature and humidity in hospitals and nursing homes was measured by thermo hygrometer. A pretested questionnaire was used to evaluate the health problems among the employs. Results indicated that employs in these hospitals were exposed to poor environmental conditions. The majority of these employs were suffering from musculoskeletal disorders, allergic reactions, respiratory disorders and other physical disorders.

1132-1137

Authors: Alireza Dehdashti, Mahdieh Ghainy, Ghasem Askari, Gholamreza Ghaeiny

Ultraviolet emission from sun considered as a hazardous parts of optical waves. This study aimed at determining exposure to ultraviolet radiation among taxi drivers in Damghan. A cross-sectional survey was conducted on a sample of taxi drivers. Individual exposure to solar ultraviolet-A was assessed during day light working hours. Exposure was determined on the basis of radiation intensity and biologically cumulated standard erythema dose. Our findings showed that exposure was varied in terms of time and geographical sites. The exposure intensity ranged from 0.01 to 15.36W/m2 and from 1.42 to 28.7W/m2 inside and outside the vehicles, respectively. Drivers had the highest exposure from June till August (17.54W/m2). Results showed lower exposure in April, May, and September (12.34W/m2). Cumulative exposure based on erythema dose showed the highest value (41.0 SED) inside vehicle at 9-10 am intervals. Taxi drivers are exposed to significant ultraviolet radiation. Geographical situation and time caused variations in exposure. Future studies should focus on the health effects so that determine the risk of exposure more accurately.

1027-1034

Authors: Mohammad Aqanaghad, Ghoamreza Mousavi, Reza Ghanbari

This work investigated the performance of an anaerobic baffled reactor (ABR) and a hybrid ABR (HABR) for the treatment of municipal wastewater (MWW) under ambient conditions and compared the ability of the two systems to meet effluent discharge standards. The reactors were studied under hydraulic retention times (HRTs) of 48, 36, and 24 hours and effluent recycling (ER) rates of 0.25-1. The startup success was determined by the COD removal efficiency. The startup lasted for 107 days. In steady state COD removal efficiency decreased from 91.4% using a 48-hour HRT to 83.5% using a 24-hour HRT in the ABR, while the COD removal efficiencies of the HABR were 2.2% greater than those of the ABR at all HRTs. The HABR met COD and BOD5 effluent discharge standards using a 36-hour HRT, while the ABR achieved these standards only with a 48-hour HRT. Using a 36-hour HRT, the HABR total nitrogen (TN) and total phosphorus (TP) removal efficiencies were 14.9% and 26.6%, while those of the ABR were 1.3% and 1% lower, respectively. The ABR and HABR met both the TSS and TP effluent standards using 48- and 36-hour HRTs, respectively, but neither met the TN effluent standard. ER did not have a positive effect on the total efficiency of either reactor. The HABR was found to be suitable for conventional MWW treatment, particularly in small cities and on-site treatment facilities.

1041-1050

Authors: Abdolreza Karimi, Behrouz Ahmadpour, Mohammad Reza Marjani

Due to the variety of treatment processes, the decision to choose the best treatment process is difficult. This paper describes a fuzzy grey relational analysis (GRA) method for selection of the optimal wastewater treatment process. The rating of all alternatives and the weight of each criterion is described by linguistic variables, which can be expressed in triangular fuzzy numbers. Then, a vertex method is used to calculate the distance between two triangular fuzzy numbers. According to the concept of the GRA, a fuzzy relative relational degree is defined to determine the ranking order of all alternatives by calculating the degree of fuzzy grey relational coefficient to both the fuzzy positive ideal solution (FPIS) and fuzzy negative ideal solution (FNIS) simultaneously. Furthermore, a case study is carried out and solved by both methods (i.e., GRA and fuzzy GRA) to show the feasibility and effectiveness of the proposed method. In the case study, five anaerobic wastewater treatment alternatives are evaluated and compared against technical, economic, environmental and administrative criteria and their sub-criteria. Finally, the related results of ranking alternatives from two methods are compared with each other's. By using both Fuzzy GRA and GRA, ABR process has been selected as the first priority and the best anaerobic process. The frequency count assessment of the Iran's industrial parks' WWTPs which have used this method and their performance, proved the priority of this method.

1058-1065

Authors: Seyed Ali Sajjadi, Ali pakfetrat, Morvarid Irani

Coloured discharge effluent into aquatic ecosystems may be carcinogenic and mutagenic besides aesthetic problems. In this work, the ability to remove (Remazol Black B) coloured water using electrocoagulation process is equipped with iron and aluminium electrodes with bentonite as a coagulant aid and natural adsorbent has been investigated. Remazol Black B was selected as a model dye and the treatment process was performed in a batch of electrocoagulation (EC) cell using iron and aluminium electrodes and bentonite. Experiments were conducted at 5 levels of various operational parameters at bench scale. The initial dye concentration was varied between 200-1200mg/L, pH ranging from 2-10; the retention time was between 0-60 minutes, the voltage studied was in the range of 5-30 V and the electrical conductivity was 0.25 to 2 Siemens/cm. Results showed that the use of electro-Aluminum and Iron, under optimum conditions of pH 2 and 4, the concentration of dye1000mg/L, the voltage of 30V and 30 min have the maximum dye removal of about 99% and 91%, respectively. Results showed that both electrode voltages increase the efficiency of the above process in paint removal with decreasing pH from 10 to 2 and increasing the voltage from 5 to 30 V. Results show that by electrocoagulation Process Coupled with Bentonite as an Aid Coagulant could be used as well as an effective method for dye removal from colored wastewater.

1072-1076

Authors: Mahnaz Yadollahi, Mohammad Farahmand, Mehrdad karajizadeh, Haleh Ghaem, Maryam Foadi, Narges Shamseddini

Environmental and occupational exposure may play a role in gender offspring. This study aimed to investigate the effect of radiation on gender ratio in the offspring of radiologists and technicians. This cross-sectional study was conducted on 262 participants with a total of 354 children. A data collection form including age, years spent in radiology practice, number of children, sex of each child, observance of radiation protection principles, and intensity of exposure based on International Commission Radiological Protection was completed. Male to female ratio was calculated 0.85 in fathers and 0.75 in mothers in comparison to this ratio estimated in Iran demographic statistics sex ratio which is 1.03. Highly-exposed parents (Prevalence ratio [PR]: 1.67, 95% confidence interval [CI]: 1.11-2.52), as well as fathers (PR: 2.72, 95%CI: 1.56-4.72), had a significant propensity to have female offspring. However, this criterion in female radiologists was not found to be significant (P= 0.57). Moreover, in fathers a significant relationship was found between the years spent in radiology field up to the time of the child’s birth or age of the parents’ at child’s conception with offspring gender (4-6 year: PR: 2.07, 95% CI: 1.15-3.72; ≥7 year: PR:1.81, 95%CI: 1.18-2.78). Highly-exposed radiology male personnel, as well as those exposed to radiation 4 years or more before the offspring’s birth, were more likely to have daughters than sons. Although no exact mechanism has been identified for this preponderance, further animal studies are required to evaluate whether x ray is an influential factor in offspring gender.

947-956

Authors: Majid Kermani, Zahra Asadgol, Hossein Arfaeinia

The concentrations of thirteen polycyclic aromatic hydrocarbons (PAHs) and six trace elements adsorbed to a fine fraction of particulate matter (PM ≤ 2.5 µm) were determined at an urban site in Tehran (Iran) during the spring period in 2013. The average concentration of PM2.5 was 41.19 µg/m3, which was 1.64 and 1.2 times higher than the annual average of WHO guidelines and EPA ambient air quality standards, respectively. The trace elements measured in the PM2.5 samples were Pb, Cd, Cr, Ni, As and Zn with the mean concentrations of 38.05, 18.2, 4.24, 4.19, 1.34, and 69:92 ng/m3 respectively. Hg wasnot found in any sample in this study. Results from correlation tests between PM2.5 concentrations and different toxic metals; which were studied in various days of the week, including holidays, 1 day after the holidays, and the other days showed that the variability between groups were significant at the 0.05 level. Exception is Hg and Zn. The mean concentrations of PM2.5 and trace elements in 1 day after the holidays were higher compared other 2 groups. Total PAHs concentrations in PM2.5 were found to be 7.92 ng/m3.The most abundant PAHs found were high molecular weight homologues (4-6 ring PAHs) such as Inp, Bgp, Dba, Bkf and Bbf, which are contributing to constituents of vehicular emissions. In general, high molecular weight PAHs are more correlated than low molecular weight PAHs. Moreover a moderate correlation was observed between total PAH concentration and PM2.5 mass.

966-971

Authors: Saeed Ardashiri, Seyed Enayat Hashemi

Environmental contamination with heavy metals is one of the main concerns on a global scale and the risk related to exposure to heavy metals present in indoor dust is considered as a serious threat to human health. Therefore, the purpose of the current research was to evaluate the heavy metals concentrations in indoor dust and their potential risks in urban areas in Bushehr city, Iran. Fifty-four indoor dust samples were collected from different buildings including lab rooms, offices, school rooms and households within the Bushehr City, during May – July 2016 and analyzed using ICP-AES (Arcousmodel, Germany). The sum of hazard quotient (hazard quotient (HQs) for heavy metals for adults declined in the order of Cr > Cd > Cu >Ni > Zn > Pb for the household while the order of ΣHQ for trace metals for adults in offices is Cr > Cd > Ni >Cu > Zn > Pb. Moreover, the values ΣHQ for trace metals for children declined in the order of Cr > Cd > Zn > Ni > Cu > Pb for the schools while the order of ΣHQ for trace metals for children in households is Cd > Zn >Cu > Cd > Ni > Cr > Pb. For all heavy metals, the HQs was about an order of magnitude higher for children than for adults. These findings can be attributed to the more vulnerability of children to the toxic substances.

982-990

Authors: Razzagh Rahimpour, Sajjad Farhadi, Mahdi Jalali

Exposing to the high-level of BTXs concentration can occur in the oil-dependent industries and may cause considerable adverse impacts on the health of employees. The main objective of the present study firstly is determining the exposure of petrochemical and oil depot workers to benzene, toluene, ortho and methyl xylenes, and p-xylene (BTXs), and secondly is estimating the lifetime cancer risk (LCR) and non-carcinogenic risk using the hazard quotient (HQ). This cross-sectional study is conducted on 85 workers at petrochemical (34 subjects) and oil depot (51 subjects) industries of Iran in 2016. In order to determine the exposure concentrations of BTXs, through inhaling way, individual sampling was carried out according to the NIOSH 1501 method. Then, estimating LCR of benzene, and non-carcinogenic risk of benzene, toluene, ortho and methyl xylenes, and p-xylene, using the HQ, has been conducted regards to criteria recommended by USEPA. The mean exposure concentration of benzene among the oil depot workers was higher than the petrochemical workers, but this difference was not statistically significant (P = 0.162). The mean exposure concentration of benzene in the oil depot workers (2.1 ± 2.53 mg/m3) was higher than the occupational exposure limits provided by the American conference of governmental industrial hygienists (ACGIH_TLV = 1.67 mg/m3). The mean concentration of toluene in the exposed workers of the oil depot (46.81 ± 22.43 mg/m3) was higher than the exposed workers of petrochemical (41.83 ± 30.06 mg/m3), but this difference was not statistically significant (P = 0.412). The results of carcinogenic and non-carcinogenic risk assessment revealed high-risk exposure level in the both investigated groups. The mean LCR of benzene in the oil depot workers was higher than the petrochemical workers (1.681E-3 and 1.163E-3, for the oil depot and petrochemical, respectively). The LCR of benzene and HQ of BTXs in the both investigated groups were higher than the reference values. In order to reduce occupational exposure to BTXs in the investigated oil depot and petrochemical, control measures should be taken in the future, as soon as possible.

997-1006

Authors: Mohammad Mehdi Babaei, Mousa Jabbari, Ahmad Ali Babaei

Individuals involved in development, repair and maintenance activities of power transmission and distribution are at high risk of electrocution. The purpose of this research is to calculate the human injuries risk of medium voltage electrocution accidents using Bow Tie model in fuzzy environment. Therefore, existing evidences and documents was investigated, and accident causes was determined using the FTA technique. Then, their outcomes were identified by using ETA and William Fine method, and Bow Tie diagrams were drawn based on the results. After that, because of inadequate data, the fuzzy logic was used to calculate the probability of the root causes and outcomes of the accident. The probability of the middle causes and top event was also calculated by probabilistic equations. The results showed that in terms of frequency, medium voltage electrocution accident with probability of 2.2E-4 is one of the significant accidents in the electricity distribution activities, as well as the outcome of "permanent total disability or death of one person" and "with no injury", are the maximum and minimum outcome of the mentioned accident with the probability of 2.1E-6 and 1.29E-10, respectively. These outcomes with the risk of 1.05E-8 and 1.29E-10 are also considered as highest and lowest risk, respectively. "Permanent total disability or death of one person" is the most important outcome of medium voltage electrocution accident, in terms of both frequency and risk. "Lack of installing earth system" and "absence of double insulation" are the most important root causes of accidents. Finally, the results of this research can facilitate financial and human resources planning, and also, the use of Bow Tie in the fuzzy environment can resolve risk assessment problem greatly in the uncertainty and lack of inadequate data.

888-893

Authors: Mohammad Ali Baghapour, Mohammad Reza Shooshtarian

Drinking water quality monitoring is a prerequisite for macro planning of development programs in metropolitans, improvement in health, and water resources management. Since WQIs (Water Quality Index) are known as comprehensive tools for interpretation of water quality, this study benefitted from this tool to determine the drinking water quality trends in Shiraz, Iran in a five year period from 2011 to 2015 and figure out the factors affecting its changes in this city. For this aim, annual data of 9 water quality parameters including DO, Fecal Coliforms, pH, BOD5, NO3, PO4, temperature deviation, turbidity, and TS were collected for 45 drinking water wells located in 4 zones (Dokuhak, Derak, Sabzpushan, and Chamran) to calculate the WQI. Pairwise comparison of years in terms of WQI values was analyzed statically using post-HOC analysis in Univariable repeated measure test. The results showed that the highest and the lowest water quality level both for annual and long term evaluations belonged to Derak and Chamran zones, respectively. All the studied wells in the five years were classified in "good" quality group. According to statistically analyze the highest significant change in water quality (p-value < 0.001) was found between the two years 2013 and 2015. In terminal years of the study, the increased concentration of TS and NO3 caused a partial decrease in water quality in some sources. These significant differences can be considered as a warning for the soon future. Therefore, it makes sense to accelerate the development of sewer systems and manage uncontrolled population growth in this city to prevent further water pollution. Permanent monitoring of water quality using WQIs seems to be essential to figure out a perspective of water quality trends and proper decision-making for developments in urban areas.

904-910

Authors: Yaghoub Hajizadeh, Sepideh Namati, Ali Ahmad Aghapour, Ali Abdolahnejad, Amir Mohammadi, Hussein Panahi, Saeed Mousai Moghanjooghi, Ali Niloonahad

Increased combustion of fossil fuel owing to the energy requirement is a main cause of air pollution throughout the world. Atmospheric precipitation is considered as a major water resource for indoor, municipal, industrial and agricultural uses. This study was aimed to evaluate the effect of air pollution on chemical quality of rain and snow in Urmia, a city in northwest of Iran. Sampling was performed during the wet seasons from October to March at six sampling stations in different locations of the city. Acidity, alkalinity, NO3- , SO42-, Cl- and pH contents of the collected samples were analyzed. All samples showed a pH value of more than 6.8, and lower acidity than alkalinity, therefore, the precipitations were not acidic. Maximum concentrations of SO42- and NO3- in the samples were 5 and 8.8mg/L, respectively. Chloride was varied from 1 to 11.5 mg/L with the highest measures observing in autumn. According to the results, concentrations of the analyzed parameters in wet precipitations in Urmia were within the natural ranges except chloride ions, which was higher than its common level in the atmosphere. This phenomenon may be the result of desert dusts which transfers by wind from the west border to Iran.

918-925

Authors: Hossein Masoumbeigi, Ghader Ghanizadeh, Bahman Ramacandi, Hossein Kardan Yamchi

Oral and dentistry (O&D) services processes may lead to exposing of personnel and patients with several microorganisms and arising of health problems. This cross-sectional study was investigated the bacteriological quality of dental unit waterlines (DUWLs) in one of the O&D center in Tehran, Iran. One hundred ninety two samples were collected and examined based on standard microbiological procedures for determining and enumeration of heterotrophic plate count (HPC), Staphylococcus aureus and Pseudomonas aeruginosa. Data were analyzed by t-test, analysis of variance (ANOVA), Kruskal-Wallis and LSD tests with SPSS software (Ver.16). The results revealed that 70% of water samples (126 samples) had a high density of contaminations that higher than recommended values for DUWLs quality. The mean of bacterial density on Saturday was more than Wednesday and was 1838 CFU/ml, 739 CFU/ml and 11 CFU/ml for HPC, P. aeruginosa, and S.aureuse respectively. The LSD test implied that the mean of bacterial density of inlet and outlet waters had significant statistical difference in various wards of the O&D center (p < 0.05). In addition, the results demonstrated that bacteriological quality in discharging water of various wards was higher than the recommended values. This research revealed that microbial water quality assessment in O&D services centers should be considered for providing of an appropriate disinfection procedure from point of infection control in dental operation services.

936-933

Authors: Elham Baseri, Mahmood Alimohammadi, Ramin Nabizadeh Nodehi, Shahrokh Nazmara, Gholamreza Jahed khaniki, Mohamad Es'haghi Gorji

In Iran, cheese is one of the dairy products that widely consumed as a main diet for breakfast. Moreover, trace metals in dairy products have recently gained considerable attention. Iranian cheese samples were collected from Tehran, Iran (February to May 2013). Trace metals including Pb, Cd, Ni, Fe, Sn, Zn, Cr, and Cu were analyzed using inductively coupled plasma optical emission spectrometry (ICP-OES) after dry ashing. All the tested metals were detected in the cheese samples. The mean concentration of metals in cheese showed the following decreasing order Zn > Fe > Cu > Ni > Sn > Cr > Pb > Cd, with values of 12.98, 7.95, 1.96, 0.83, 0.46, 0.37, 0.34, and 0.01 mg/kg, respectively. There were no significant differences between types of cheese samples in terms of content of trace metals (p>0.05). All the samples had Pb contents of greater than Codex limit (0.02 mg/kg). According to the measured values of the metals in this study, the intake of all the studied elements through the common consumption of cheese in Iran was below the dangerous level according to permissible intake value for each metal. Also, levels of correlations between the element pairs were analyzed.