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Highly ordered periodic mesoporous organosilica (PMO) with large-pores (9.3 nm) synthesized using novel and cost-effective route. The synthesized PMO was then functionalized by p-phenylenediamine (PPD) and incorporated in polyethersulfone (PES) nanofiltration membrane| with various dosage using phase inversion method. The prepared membranes were characterized with FT-IR/ATR, FE-SEM and EDX techniques. The overall porosity, the mean of pore radius, water contact angle, fouling, permeation, and rejection were computed. As a result, the hydrophilicity and the pure water flux of membranes were significantly enhanced after modification with PMO-PPD due to its high hydrophilic nature as nanofiller. Ultimately, the modified membrane with 0.25 wt% of PPD was found the ideal membrane with water contact angle of 54.2%, pure water flux of 33.7 L/m2 h, porosity of 74.1%, and mean pore radius of 4.96 nm. This membrane showed the maximum increase in water flux and superlative anti-fouling growth when compared to the other studied membranes. Moreover, among modified membranes with various quantity of PPD, the performance of the PES-PMO-PPD 0.25 wt% was the best for rejection of MO dye (96.7%), Pb(II) (93.1%), Na2SO4 (73.0%), MgSO4 (41.6%), and NaCl (33.7%).

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Birds are susceptible to environmental changes, which make them particularly important as indicators of environmental contamination, including metal concentrations. In the present study, the concentrations of arsenic (As), cadmium (Cd), chromium (Cr), iron (Fe), lead (Pb), manganese (Mn), nickel (Ni), and zinc (Zn) in the tail and flight feathers of greylag goose, mallard, pintail, pochard, and wigeon were investigated from the south of the Caspian Sea in Iran by the electrothermal atomic absorption spectrometry (ET-AAS) method. The trend of metal concentrations in both types of feathers of all the examined species was as follows: Fe < Zn < Mn < Cd ∼ Cr ∼ Ni ∼ Pb < As. The interspecies variation in concentrations of almost all the studied metals was observed, as well as the significant differences between feather types. The only exception was Ni, the medians of which were comparable in tail and primaries. Correlations of concentrations of Cd, Mn, Ni, Pb, and Zn in primaries and tail feathers were positive and statistically significant. Elevated concentrations of Cd, Cr, Mn, and Pb were noted so the possibility of environmental contamination of the area is suspected.

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The purpose of this article was to investigate the levels of metals, cadmium, lead, and zinc, in Western reef heron (Egretta gularis) (n = 15) in order to (1) examine the sex-related variation in trace metal accumulation and (2) determine the significant differences between the metal concentrations in the kidney, liver, and pectoral muscle. Bird samples were collected from throughout the Hara biosphere reserve of southern Iran, during November and December 2010 and the concentration of metals were measured using a Shimadzu AA 680 flame atomic absorption spectrophotometer. The overall cadmium, lead and zinc concentrations means were measured as 0.8 ± 0.1, 3.4 ± 1.1, and 29.4 ± 12.9 µg/g for kidney; 0.7 ± 0.1, 2.2 ± 0.5, and 65.9 ± 20.7 µg/g for liver; and 0.2 ± 0.1, 2.2 ± 0.7, and 17.6 ± 12.9 µg/g for pectoral muscle, respectively. The results showed that with the exception of cadmium in liver, there were no significant differences between males and females (t test, p > 0.05). In the contrast, the results indicated metal concentrations differed significantly in kidneys, livers, and pectoral muscles among tissues in Western reef heron (one-way analysis of variance, p < 0.001).

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The accumulations of Cd, Ni, Pb, and Cr were measured in muscle, gill, kidney, and liver of Platycephalus indicus and Pampus argenteus. Our results indicated that all metals were found to be the highest in tissues in P. indicus (benthic species). Except Ni in P. indicus, concentrations of metals and bioaccumulation factor were in the following sequence: liver > kidney > gill > muscle. The data revealed that there is a significant negative correlation between concentrations of metals and size and age factors. The Ni and Cr levels in the muscles were higher than the maximum acceptable limit recommended by WHO and FEPA. Similarly, the concentration of Pb measured in P. indicus muscle exceeded the FAO standard limit.

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The aim of this study was to assess the pollution status of metals in sediments of Hara Biosphere Reserve using pollution indicators. For this purpose, sediment samples from nine locations were collected and characterized for metal content (Pb, Cr, Zn, Cu, and Fe) using the total digestion technique. Comparison of metal concentrations with that of sediment quality guidelines (SQGs) demonstrated no association with negative biological effects for Cu and Zn, while the values of Pb and Cr mainly illustrated to have association with negative biological effects. The results of the geo-accumulation index (Igeo) indicated no contamination for Cr, Cu, Zn, and Fe, while the values of Pb demonstrated to have moderate contamination based on I geo values. The analysis of the enrichment factor (EF) showed no enrichment for Cu and Zn and minor enrichment for Pb and Cr. Similar results were also found for quantification of contamination (QoC) analysis, where the values of Cu and Zn demonstrated to have a geogenic source of contamination, while the values of Pb and Cr mainly illustrated to have an anthropogenic source of contamination. According to EF and QoC calculations, the values of Cu and Zn were derived mainly from natural processes and exposure of material from the earth's crust, while the values for Pb and Cr were enriched by anthropogenic activities. The results of the contamination factor (Cf(i)) demonstrated low contamination levels for Fe, Cr, Zn, and Cu and moderate contamination levels for Pb. The pollution load index (PLI), showing the overall contamination of metals, demonstrated moderate pollution status in the study area.

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This study determined the concentration of heavy metals (Al, Cr, Cu, and Zn) in water and sediments at nine sites in the Hara biosphere reserve of southern Iran during the summer and winter 2010. Determination of Al, Cr, Cu, and Zn in water was carried out by graphite furnace atomic absorption spectrometer (Shimadzu, AA 610s) and in sediment by flame atomic absorption spectrometer (Perkin Elmer, AA3030). Results showed that the heavy metal concentrations in the water samples decreased in the sequence of Zn > Al > Cu > Cr, while in sediment samples were Cr > Zn > Cu > Al. Data analysis indicated that with the exception of Al, there was a Pearson's correlation coefficient between pH and Cu, Zn, and Cr at α = 0.01, 0.05, and 0.001 in sediment (in winter), respectively. There were also significant differences between heavy metals of Cr, Cu, and Zn during the two seasons (p < 0.001) in the water and sediment.

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The concentrations of four heavy metals (Pb, Cd, Ni and Cr) were measured in tissues of pelagic (Rutilus caspicus) and benthic (Neogobius gorlap) fishes from the Miankaleh international wetland. The maximum concentrations of Pb, Cd, Ni, and Cr (2.06, 1.20, 1.14 and 0.70 µg g(-1), respectively) were measured in the liver of N. gorlap, while the lowest concentrations were measured in muscle tissue collected from R. caspicus (Pb 0.67; Cd 0.25; Ni 0.21 and Cr 0.08 µg g(-1)). The mean concentrations of metals in liver of R. caspicus and N. gorlap followed a trend where Pb > Cd > Ni > Cr, whereas in R. caspicus and N. gorlap gills and N. gorlap muscle the following trend was observed Pb > Ni > Cd > Cr. The data of presented study show that the liver and gill tissues have higher metal concentrations than muscle and also the metal concentrations in tissues of N. gorlap (benthic) were higher in comparison with R. caspicus (pelagic).

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The metal levels (Hg, As, Cu, and Zn) in tissues of edible fish species (Pampus argenteus, Sillago sihama, Liza klunzingeri and Platycephalus indicus) were evaluated. The metal concentrations were found to follow the order: liver > kidney > gill > muscle, except for Zn from P. argenteus showing an inversion of liver and kidney. Generally, the benthic species (P. indicus and S. sihama) showed a marked potential for tolerating high metal levels. Significant negative correlations were found between fish size/age and metals concentration in the most organs. The element levels in the muscles were lower than the maximum allowable concentrations, except for mercury in S. sihama and P. indicus.

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The metal pollution in Sediments and Avicenna marina tissues in the Hara Biosphere Reserve was monitored for Lead (Pb), Cadmium (Cd), and Nickel (Ni) with atomic absorption spectrometer. The results showed that the mean concentration of Pb, Cd, and Ni in the water and sediments were much higher than the recommended threshold limits in the most stations, also the highest means of Pb, Cd, and Ni were observed in Avicenna roots and it were 25.26 ± 4.86, 2.17 ± 0.74, and 26.72 ± 6.17 (µg g(-1)) respectively. Calculating BCF (bioconcentration factor) index illustrates that A. marina accumulates Pb, Cd, and Ni 1.62, 1.52 and 0.73 times greater than sediment levels respectively, So it can show that A. marina may be employed as a biological indicator exposure of Cd, Pb, and Ni with temporal monitoring, also the factories were main sources of metals contamination in the Hara Biosphere Reserve.

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The objective of the present study was to investigate the levels of metals, namely cadmium, lead, and zinc, in Siberian gull (Larus heuglini) (n = 15), in order to: (1) examine the sex and gender related variation in trace metal accumulation, and (2) to determine the significant between metal concentrations in the kidney, liver, and pectoral muscle. The concentrations were different between the tissues of bird as well as among the interaction (sex × age), but this difference (except cadmium in liver and zinc in kidney) between the gender (male and female) and age (adult and juvenile) didn't exist. Results showed that the metal concentrations in the Siberian gull were decreased in sequence of kidney > liver > muscle. The cadmium, lead, zinc concentration overall means they were measured as 2.2 ± 0.7, 8.8 ± 2.5, and 91.1 ± 37. 1 µg/g for kidney, 1.1 ± 0.2, 5.1 ± 0.8, and 68.3 ± 27.8 µg/g for liver, and 0.8 ± 0.1, 3.4 ± 0.6, and 34.4 ± 23.2 µg/g for pectoral muscle, respectively.

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The objective of the present study was to investigate the levels of heavy metals, namely, chromium, copper, cobalt, nickel, and iron, in Western Reef heron (Egretta gularis) (n = 15) and Siberian gull (Larus heuglini) (n = 15) to (1) compare metal concentrations between two bird species with different trophic level, molting pattern, and life strategy; (2) examine species- and sex-related variations in trace-metal accumulation; and (3) determine the significance between heavy-metal concentrations in kidney, liver, and pectoral muscle. Bird samples were collected from November to December 2010 throughout the Hara Biosphere Reserve, and heavy metals were assayed by using a Shimadzu AA 680 flame atomic absorption spectrophotometer; the results were given as µg/g dry weight. Metal concentrations were different between the bird species as well as among bird tissues, but there was no difference (except chromium and iron in kidney) between sex (male vs. female). Mean levels in kidney of Western Reef heron and Siberian gull were chromium (0.96, 2.32 µg/g), copper (6.31, 10.55 µg/g), cobalt (0.12, 0.14 µg/g), nickel (1.13, 1.32 µg/g), and iron (37.92, 39.64 µg/g), respectively, whereas in liver they were chromium (1.05, 2.75 µg/g), copper (8.93, 12.63 µg/g), cobalt (0.09, 0.17 µg/g), nickel (1.1, 2.27 µg/g), and iron (34.03, 44.21 µg/g), respectively. Results showed that heavy-metal concentrations in Western Reef heron were decreased in the sequence iron > copper > nickel > chromium > cobalt, whereas in Siberian gull they were decreased in the sequence iron > copper > chromium > nickel > cobalt. Results also showed that in both species, the highest chromium and nickel concentrations were measured in female birds and the lowest in male birds, whereas the highest copper, cobalt, and iron (except iron in liver) concentrations were measured in male birds and the lowest in female birds.

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The main objectives of article were monitor the metal concentrations of cadmium, lead, copper, zinc, cobalt, and iron, in the feather of shorebirds species, Western Reef Heron (Egretta gularis) and Siberian Gull (Larus heuglini) from Hara Biosphere Reserve of Southern Iran; and identify any relationships between species. Assaying heavy metals by using Shimadzu AA 680 flame atomic absorption spectrophotometer, the results were given as micrograms per gram dry weight. The concentrations of heavy metal were found to follow the order of iron>zinc>copper>lead>cadmium>cobalt for E. gularis and of iron>zinc>lead>copper>cadmium>cobalt for L. heuglini. Also, they showed that the cadmium, copper, and cobalt concentrations were higher in females than in the males, while the lead concentration for E. gularis and L. heuglini was higher in males. The cadmium concentration means they were measured as1.16 and 1.37 µg/g for E. gularis and L. heuglini, respectively, whereas the lead concentration means 7.04 and 5.48 µg/g for E. gularis and L. heuglini, respectively. The concentrations of nonessential trace elements in E. gularis and L. heuglini were generally comparable to values reported in other studies. The average levels of lead we observed in these birds were greater than 5 µg/g dry weight in the feather that is known to be associated with adverse behavioral or reproductive effects. Data analysis showed that there was a positive correlation between copper and zinc (P < 0.01), copper and cobalt (P < 0.05).

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OBJECTIVES: The primary objective of this study was to determine whether local and imported cigarette brands used in , have elevated levels of metals or not. The produced data of cigarette brands are compared both with each other and with the existing brands in different countries. MATERIALS AND METHODS: In present study, nineteen various cigarettes brands were randomly purchased from the commercially available cigarettes in Iranian market (Birjand city) including local Iranian branded and imported cigarettes. All samples were analyzed for heavy metals, viz. Cd, ,Cu ,Co Ni, Zn and Pb by graphite furnace atomic absorption spectrophotometer after microwave-assisted wet digestion method with nitric and perchloric acids. RESULTS: The observed average metals concentrations for cadmium in all cigarette brands was 2.71 and ranging 1.76 to 3.20, copper 9.7 (5.18-17.6), cobalt 4.42 with range of 2.57-6.49, nickel 17.93 (10.0-30), zinc 27.02 (18.1-42.2) and value for lead was 2.07 with range of 1.05 to 3.10 (µg/g dry weight) and mean metals content per cigarette was also measured. The produced data of imported and local cigarette brands are discussed and compared together and with studies from elsewhere. CONCLUSION: The investigation may confirm that the level of metal contents in Iranian cigarettes is similar to the other parts of the world. However, the concentration of these metals was slightly higher in comparison with other investigation.

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The main objectives of study were to monitor the metals concentrations, in freshwater fish species, Carassius gibelio and Esox lucius; and to identify any relationships between species and bioaccumulation of metals. The highest concentration of metals (cadmium, 1.96; copper, 24.2; zinc, 49.6; lead, 5.4; chromium, 4.4) between the fish species and tissues was in the liver of Esox lucius, while the lowest (cadmium,0.21; copper,7.2; zinc,19.4; lead,0.9; chromium,0.6 µg/g) found in the muscle of Carassius gibelio. Results showed that the metal concentrations were in fishes in descending order of zinc > copper > lead > chromium > cadmium, similarly in the tissue liver > kidney > gill ~ intestine > muscle.

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OBJECTIVE: To determine the effects of water hardness on the toxicities of cobalt (Co) and nickel (Ni) to a freshwater fish, Capoeta fusca. METHODS: Toxicity was investigated by static bioassay. Fish were exposed to cobalt (as CoCl(2)) and nickel (as NiCl(2)) for 96 h in waters with two levels of hardness ("hard" and "very hard", nominally 130 mg/L and 350 mg/L as CaCO(3), respectively). RESULTS: Water hardness had a significant effect on the acute toxicity of both elements. The 96 h LC(50) values for Co were 91.7 mg/L and 204.8 mg/L in hard and very hard waters, respectively, and for Ni the 96 h LC(50) values were 78.0 mg/L and 127.2 mg/L, respectively. CONCLUSION: The fish were more sensitive to Co and Ni toxicity in hard water than in very hard water; very hard water protects C. fusca against the toxicity of Co and Ni.

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To investigate whether leaves of plane trees (Platanus orientalis) are damaged by traffic pollution, trees from a megacity (Mashhad, Iran) and a rural area were investigated. Soil and air from the urban centre showed enrichment of several toxic elements, but only lead was enriched in leaves. Leaf size and stomata density were lower at the urban site. At the urban site leaf surfaces were heavily loaded by dust particles but the stomata were not occluded; the cuticle was thinner; other anatomical properties were unaffected suggesting that plane trees can cope with traffic exhaust in megacities.

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