فصلنامه سلامت و محیط زیست
سال هشتم شماره 3 (پیاپی 29، پاییز 1394)

Remaining of crude oil in storage tanks usually results in accumulating oily sludge at the bottom of the tank, which should be treated and disposed of in a suitable manner. The efficiency of in-vessel composting process in removing total petroleum hydrocarbons (TPH) from bottom sludge of crude oil storage tanks was investigated in the present study. The sludge was mixed with immature compost at the ratios of 1:0 (as control), 1:2, 1:4, 1:6, 1:8, and 1:10 (as dry basis) with the initial C:N:P and moisture content of 100:5:1 and 55% respectively for a period of 10 weeks. The moisture adjustment and mixing process were done 3 times a day during the composting period. Sampling and analysis of TPH and pH were done every week and every two days, respectively. TPH removal in the 1:2, 1:4, 1:6, 1:8, and 1:10 composting reactors was 66.59, 73.19, 74.81, 80.20, and 79.91%, respectively. Thus, initial adjustment of sludge to immature compost ratios plays a great role in reduction of TPH. The results of the control reactors indicated that the main mechanism of TPH removal in the composting reactors was biological process. In-vessel composting by addition of immature compost as amendment is a viable choice for bioremediation of the bottom sludge of crude oil storage tanks.

Collection and disposal of waste has an important role in public health. Isolation and separation procedures at the origin is considered as one of the most important and least costly methods of isolation and separation of waste. This study was aimed to culture and educate those involved in recycling and waste reduction in the Kalaeh City using two educational methods.. This semi-experimental study was conducted in Kalaleh City. In the social and cultural context, Kalaleh was divided into six regions. Using cluster sampling, regions were selected randomly. In each area, 120 samples were used. The first group was face-to-face trained and the second group received training through the training package. Waste collection period was 60 days. After this time, the questionnaires were again filled up and the impact of teaching methods were investigated. Face-to-face training resulted in increasing waste separation from 70.8 (before training) to 95%. Whereas, this figure in the group receiving training package increased from 57.5 (before training) to 86.7%. Waste recycling rate was between 0.6 to 1 Kg per person per week. These wastes included paper, glass, plastic, and metal containers. On average, the waste recycled in face-to-face training group and training package group was 91 and 83 Kg per week. Knowledge, attitude and cooperation in waste separation increased after training in both groups. However, in the face-to-face training group, the knowledge and participation in waste separation was more compared with training package group. Continuous training and organizing waste separators could be helpful to re-use waste. It causes less pollution of the environment, reduce the transmission of diseases associated with non-systematic disposal of solid waste, reduce costs and increase awareness about the problems and issues of solid waste, and reduce the solid waste volume.

Furfural is one of the toxic chemical compounds used in many industries such as petrochemical, food, paper products, pharmaceutical, etc., due to having some characteristics. Therefore, furfural could be found at different concentrations in the effluent from these industries and can enter the environment. Hence, the aim of this study was the assessment the efficiency of a low cost bentonite modified with cationic surfactant in the removal of furfural from aqueous solution. In this experimental study, bentonite was purchased from one of the Mines of Zanjan Province, Iran and then the efficiency of bentonite modified with the cationic surfactant CTAB (CTAB-Bent) was assessed in the adsorption of furfural from aqueous solution. Activated carbon (AC) was also purchased as commercial grade. Under optimum conditions, the removal efficiency of AC and CTAB-Bent was about 52 and 66%, respectively. For both adsorbents used in this study, the increase of contact time and sorbent dosage resulted in increasing the removal efficiency, but the removal efficiency was decreased with the increase of furfural initial concentrations. Regarding pH, the removal efficiency was the highest in relative acidic and neutral environment, (60 and 69% for AC and CTAB-Bent respectively). The kinetics studies revealed that the highest correlation coefficients were obtained for the pseudo-second order rate kinetic model. Adsorption data from both adsorbents was also fitted with Langmuir isotherm. It was found that modified bentonite with CTAB as a natural adsorbent could have better efficiencies compared with activated carbon in the furfural removal, although more contact times is needed.

Rapid growing of Triton X-100 application in industries results in its appearance in effluents and threaten the aqueous ecosystems. Triton X-100 is not biodegradable and can accumulate in food chain. In this study, sorption capacity of six synthesized zeolites with different regular porous structure was studied for triton X-100 (TX-100) surfactant and the results were compared with Clinoptilolite natural zeolite of Damavand region. Within all zeolite studied, Beta(200) showed the highest sorption capacity (about 575 mg/g), which is due to its regular pore structure with large pore diameter, channel intersections, high SiO2/Al2O3 ratio and high surface area. Langmuir monolayer isotherm and pseudo-second-order kinetic equation could provide well-fitted to the experimental data in simulating adsorption behavior of TX-100 over Beta(200) zeolite. The adsorption feature was internal sorption and the intraparticle diffusion might be a rate-limiting control for Beta(200) zeolite. Results of experiments demonstrated that the hydrophobic zeolites with large pore diameter such as Beta(200) could be effective sorbents for industrial wastewater treatment features.

Objective and Fluoride is an element widely found in the earth crust. Advantages and disadvantages of fluoride in the human body are depended on its concentration. Long-term consumption of drinking water contaminated with arsenic can cause adverse health effects such as skin lesions and cancer in humans. The aim of this study was to study efficiency of nano alumina on multi walled carbon nano tube for removal As(V) and fluoride from aqueous solution. In this study, nano-scale crystalline alumina was synthesized on single walled carbon nanotube by sol-gel method for using as a sorbent for solid phase extraction of Fluorine ion and arsenic(V). Response surface methodology based on Box-Behnken was used to assess the effect of independent variables on the response function and prediction of the best response value. In this study, effect of different parameters, such as contact time (10 to 120 min), pH (3-9), adsorbent dosage (0.25-1.5 g/L) and initial concentration of fluoride (2-8 mg/L) on efficiency of process was investigated. The structure of nano-scale alumina on multi walled carbon nano tube was determined by XRD and SEM techniques. Moreover, Freundlich and Langmuir isotherm models were used to calculate equilibrium constant. It was found that by increasing contact time and adsorbent dosage the rate of fluoride removal increased. However, by increasing pH and initial concentration the efficiency of fluoride removal decreased. High value for R2 (0.94) shows that removal of arsenic(V) can be described by this model. The Freundlich isotherm was the best fitted graph for experimental data with R2 more than 0.997. In this study, it was observed that efficiency of arsenic(V) and fluoride removal was greatly increased by using nano-scale alumina on multi walled carbon nanotubes (MWCNTs).

In the outbreak of infectious diseases, the on time epidemiological, environmental, and laboratorial investigations result in rapid diagnosis of cause and source of the outbreaks and decrease the diseases spread and public health loss. Following the outbreak of gastroenteritis in Pardis Town in January 2014, this research was conducted to identify the cause, source, and route of transmission of the outbreak. First, the descriptive epidemiological study was conducted using checklist and the stool samples were prepared and analyzed. The drinking water quality in Pardis during and before the outbreak was obtained from National Environmental Health Network. The community water supply system consisting of watershed, water resources, pipelines, storage reservoirs, disinfection systems, and distribution network were inspected and sampling and detection of thermotolerant coliforms and norovirus in water samples were performed according to the Standard Methods. There were 6,027 patients with symptoms of nausea, vomiting, cramps, mild diarrhea, and mild fever. The distribution of the disease in all age groups, gender, ethnicity, and location was uniform. Out of nine stool specimens, molecular testing of norovirus in six samples was positive. Hazards identified in the water supply system consisted of a water pipe fracture occurred two days before the outbreak, illegal connection of landscape irrigation system to the drinking water supply network, the use of unprotected Fellman wells as the resource of water supply, and discharge of domestic wastewater into the water resource upstream of the Fellman wells. The water samples taken from the Fellman wells had fecal contamination (11 out of 12 samples), but because of weakness and limited experience in identifying norovirus in water samples, norovirus was not detected in the raw water samples. This study showed that the pathogen came from a single source. Clinical symptoms, epidemiological evidence, the results of analysis of human stool samples, fecal contamination of raw water samples and norovirus resistance to the standard amounts of free residual chlorine in water indicated that the outbreak caused by consumption of contaminated drinking water (discharge of domestic wastewater to water supply system). In order to prevent similar outbreak, resolving the observed bugs in the water supply system and implementation of water safety plan is recommended.

Phenol is one of the industrial pollutants in wastewaters, which due to its toxicity for biological systems various pretreatment processes have been used for its detoxification. In this study, the combination of catalytic ozonation process (COP) and sequencing batch reactor (SBR) were used for detoxification of these types of wastewaters.Materials and In this study, the effect of COP on phenol degradation, COD removal, and detoxification of wastewater was investigated. To determine the acute toxicity of effluents and identification of intermediate compounds produced in COP, bioassay using Daphnia Magna and GC / MS were used, respectively. Then, phenol and COD removal of pretreated wastewater was investigated in SBR. It was found that under optimal conditions in COP (time = 60 min), the concentrations of phenol and COD reduced from 500 and 1162 to 7.5 and 351 mg/L respectively and pretreated effluent toxicity (TU = 36), after rising in the initial stage of reaction, effectively reduced at the end of process (TU=2.3). the integration of this process with SBR could decreased the COD and phenol concentration less than the detectable range by HPLC. Results showed that COP has a high effect on biodegradability, detoxification, and mineralization of phenol and combination of COP with SBR process can effectively treat wastewaters containing phenol.

Background and Soil contamination resulted from either natural or anthropogenic factors reduces environmental quality. The aim of this study was to evaluate the geoaccumulation, contamination factor, and principal component analysis indices to estimate topsoil contamination in Aran-Bidgol town. 135 topsoil samples were collected from Aran-Bidgol town and the metal concentrations of Cd, Pb, Ni, Cu, and Zn in each sample were determined. The index of geoaccumulation (Igeo), contamination factor (CF), and principal component analysis (PCA) techniques were applied to determine the status and trends of soil contamination in this region. The inverse distance weighting (IDW) was then used to map these soil contamination indices. The research found that the means concentrations of Cd, Pb, Ni, Zn, and Cu were 0.72, 11.41, 29.87, 48.59, and 14.82 mg/kg respectively all exceeded the background values. Mean Igeo and CF of elements followed the order: Cu> Cd> Ni> Zn≈ Pb. The Igeo and CF maps showed higher values of Cd, Pb, and Zn in areas near industrial estates, brick kilns, and urban areas whereas higher levels of Cu and Ni occurred in urban and agricultural areas. According to the PCA index, two principal components were identified that Cu, Ni and Zn were highly loaded in PC1 and Cd and Pb occurred in PC2. Results indicated that the concentration of Pb and Cd are mostly affected by human activities, whereas Ni, Zn, and Cu contents are controlled by both anthropogenic and natural sources.

In the field of environmental risk assessment, the earthworms are considered as the major component of the soil, and are important bio- indicators to measure the environmental health and quality of the soil. Hence, the present study aimed to prove the biological effectiveness of Eisenia fetida earthworms in Bioremediation the soils contaminated with chromium and cadmium.Methods and Materials: The study batch experiments were conducted on the soil samples contaminated with chromium and cadmium. The initial concentration of chromium and cadmium in soil was 0.04 and 0.08 mg/g. 30 worms were added to each 500 g soil samples. Chromium and cadmium concentration in soil and in the body of worms was measured at two time periods of 21 and 42 days. ICP spectrometry we used to measure the concentration of chromium and cadmium. The data were analyzed using SPSS version 11.5 software. There was a significant correlation between the reduction of chromium and cadmium metals in the soils and the accumulation of chromium and cadmium metals in the worm’s body. A significant decline of chromium levels of the soil was observed in the days 21 and 42 during the study compared to the initial amount of 0.1 mg/g. On the other hand, chromium concentration of the soil decreased from 0.14 to 0.1 mg/g after 42 days. said the research indicated that increased mortality of worms in the soil at a concentration of 0.08 mg/g of chromium, using the worms for bioremediation is not recommended. Although, this method is effective to remove cadmium from the soils having cadmium with concentrations of 0.04 and 0.08 mg/g but it needs further investigation.

Assessing human bioclimatic is foundation for many programs and plans, especially in the field of healthcare. In this study, human thermal comfort and its relationship with the incidence of diseases were investigated in Kurdistan province. The daily data of temperature, wind speed, relative humidity, and cloudiness between the years 1995-2014 were used. In the First step, Tmrt parameter was calculated in the Ray Man software environment. Then, UTCI index values were calculated using Bioklima software. In the final step, the climatic comfort zones were drawn in the ArcMap software. It was found that the UTCI values change from 20 to -23. Bijar and Zarrineh stations have the highest cold stress conditions. The calculated values showed that severe cold stress conditions prevail in most parts of the province almost throughout the year. The correlation coefficient values showed that the highest correlation with the height was observed in the cold months of the year (December- February). The results of UTCI zoning also showed that the central parts of the province consistent with the higher altitude areas had severe stress conditions. The research showed that the province is faced with moderate to severe stresses in terms of human stress conditions. In the cold periods of the year, it will be more severe and more cold conditions are experienced in high places.

Considering the environmental problems raised from current plastic packaging, edible and biodegradable films could be developed and also be effective in controlling the chemical and microbial properties of food especially if their effect be strengthened by adding natural antioxidant and antimicrobial agents like herbal essential oils. This study aimed at assessing the effect of packaging with chitosan film containing garlic essential oil on the chemical changes of chicken fillet during storage at refrigeration temperature. Different levels of garlic essential oil (0, 0.5, 1 and 2%) were used in chitosan film preparation. Through casting method and using glycerol as plasticizer and tween 80 as emulsifier, different films were prepared after homogenization and molding. Chemical tests were conducted in days 0, 2, 4, 7, 10, and 14 on chicken fillets covered with different films and stored at 4 °C. Statistical analysis was performed using SPSS software. Samples covered with different films showed lower values for pH, total volatile nitrogen (TVN), Thiobarbituric acid-reactive substances (TBARs), and peroxide index (P.V) compared with controls during the study (p &le 0.05). Generally, a dose-dependent trend was observed by essential oil addition. Chicken packaging with chitosan film especially by adding various levels of garlic essential oil could had a preventive effect on major chemical spoilage factors. Considering the relatively similar preventive effect of 1 and 2 % essential oil levels and also economic aspects, optimum dose for essential oil could be 1 % in the film.

One of the air pollutants is volatile organic compounds (VOCs). Benzene, as a part of petrol, is a VOC, known to be carcinogenic to human beings (Group 1) and it has widespread application in various industries and professions. Hence, the aim of the present study was semi-quantitative and quantitative health risk assessment of petrol bank workers exposure to benzene via inhalation in the Tehran, Iran. For these purpose, this descriptive cross-sectional study was conducted in three stages. First stage consisted of measurement of benzene in two groups of participants: (1) petrol bank workers and (2) non-exposed people as control group. The second stage included the evaluation of worker's exposure to benzene and semi-quantitative risk assessment, and the third stage was estimating the lifetime cancer risk caused by exposure to benzene. Benzene mean concentration was near the threshold limit value (1600 µg/m3) and the mean benzene personal air level was 1527±246.4 µg/m3 in the petrol bank areas. With regard to semi-quantitative risk assessment method, benzene introduced as the most hazardous chemical with risk ratio of 4.5 has 5th rank in risk levels (Extremely dangerous). Lifetime cancer risk estimation showed that in petrol bank workers the excess lifetime cancer risk was 27.5 times higher than unexposed group and the chance of cancer was one in a 1000 petrol bank workers. This study indicates that petrol bank workers in Tehran have a potentially high cancer risk through inhalation exposure. Thus, preventative actions regarding to this hazardous and carcinogenic chemical must be started as soon as possible.