جستجوی مقالات مرتبط با کلیدواژه « فلزات سنگین » در نشریات گروه « مهندسی دریا »

The aim of this study was to determine the accumulation of heavy metals (nickel, mercury and cadmium) in muscle and skin tissue of Tanoalosa ilisha in Khuzestan province (Karun River, Arvand Rud River, Bahrakan). For this purpose, after determining the stations by GPS, sampling of the Tanoalosa ilisha fish was performed using a fishing trip. After catching fish randomly, fish were placed in contact with ice in standard conditions and quickly transferred to the laboratory. Subsequently, the samples were evaluated for measuring the factors of this study based on international standard methods. The results of this experiment showed that the highest concentrations of heavy metals evaluated in this research (nickel, cadmium and mercury) were at the Bahrakan station and the lowest concentration of metals were in the Arvand Rud station. Generally, the concentration of nickel metal found in the fish muscle in Karun was 1±162.11 ???and Arvandroud Rud station, 0.0±908.09, was higher than the FDA limit. However, nickel in the Tanoalosa ilisha fish skin was higher than the permissible level in all three stations, 1±901.219, 1±588.22. 1±222.15. Regarding cadmium levels in muscle tissue at the Bahrekan and Karun stations, 0.0±547.08, 0.0±421.05, were higher than the WHO and below the FDA recommendations, but at Arvand river the levels were lower than WHO and FDA limits. However, the cadmium content of the endangered fish of all three stations, 0.0±648.106, 0.0±494.07, 0.0±340.09 was higher than the WHO standard and was below the FDA standard. The accumulation of mercury metal in skin tissue and Tanoalosa ilisha fish muscle in all three stations was lower than the FDA and FAO limits. In addition, the amount of elemental accumulation in fish skin was more intense than in muscle tissue.

In this study nickel and vanadium heavy metals were investigated in sediments and gammarus in Gilan Province. Sampling was carried out from sediments and dominant Gammarus, from 5 stations in Gilan province, in the spring of 2016. Nickel and vanadium analysis was carried out using an ICP/MS instrument. The results were statistically analyzed using one-way ANOVA and Duncan's test. The results showed that the amount of vanadium in sediment and Gammarus was higher compared to nickel and more accumulation of both metals was observed in the western part of the province (Rudsar area) compared to the eastern part. There was no significant correlation between environmental parameters and the concentration of metals. Based on the regression equation, a weak positive correlation was found between the amount of nickel and vanadium in sediments and Gammarus, which was not significant. Comparing results with NOAA standard (2004), the amount of nickel and vanadium in the sediments of the coast of Gilan province were not higher than the permissible range.

To estimation of heavy metals pollution in Gorganroud river sediments using data Mining, sediment was collected in two seasons (spring and summer) at 10 stations with three replications. After analyzing the samples, heavy metal data were extracted. Then proposed method was included the steps for starting and collecting data, pre-processing data, constructing the model as well as evaluation and output. construction of model was performed using 3 Naive bayes algorithms, decision tree, and k- nn, and then the evaluation was carried out to evaluate the accuracy, precision, recall, and error.In the output of the proposed method, all three algorithms have positive results for our data. The values of the accuracy, precision, recall, and error for Naive bayes algorithm were 92%, 44.49%, 88.88%, 8%, respectively; the values of the Naive bayes algorithm were greater than the decision tree k-nn algorithm. Also, the K-nn algorithm was better than the decision tree and the accuracy and accuracy of this algorithm were more than the decision tree algorithm. Thus, in this thesis, the Naive bayes algorithm showed better results with this data.

Heavy metals are one of the most important environmental issues, due to their toxicity and resistance. In this study, the concentration of heavy metals (Alomunium, iron, mangenise, chromium, vanadium, nickele, zinc, arsenic, lead, cobalt, and cadmium) in surface sediments of Chabahar Bay was determined by using ICP OES to assess the risk of the metals for aquatic environment. The sampling stations were consisted of Posm, desalination plant, Konarak, Ramin, the entrance of Chabahar Bay and a reference station. The concentration of arsenic in the sediments of sampling area, especially at deeper parts of Ramin and coastal parts of Posm and Konarak, was 2.5 to 3 times ghier than threshold effect level (TEL), except for deeper parts of Posm. The results of this study showed that the concentrations of chromium (except for Ramin 2 and Tss 2), aresenic cadmium and nickel (except for Tiss 2) were 1-2.5, 1-5, 1-4 times higher than their threshold levels and international guidelines (NOAA و ISQGs), respectively. The results of this research showed that the dominant source of heavy metals in the sediments of sampling area was natural; except for cadmium and chromiumwhich originated from anthropogenic sources. However in some stations anthropogenic sources ffected on the concentration of some elements such as arsenic, lead and nickel.

This study determined the concentrations of mercury, lead, cadmium and arsenic in the muscle and liver of Liza klunzingeri from Khuzestan province. In this study, 18 samples of L. klunzingeri were collected from Hendijan seaport in winter. The concentrations of heavy metals were obtained by atomic absorption spectrometry (Perkin Elmer 4100). The average length and weight of L. klunzingeri were 18.77±0.95 cm and 78.27±3.68 g, respectively. Concentration of Hg, Cd, Pb and As in muscle of L. klunzingeri were 0.033±0.009, 0.171±0.017, 0.265±0.009, 0.092±0.008 mg kg-1 dry weight. Also, the amounts of these toxic metals in L. klunzingeri were 0.052±0.009, 0.224±0.011, 0.323±0.017, 0.160±0.008 mg kg-1 dry weight, respectively. The mercury, cadmium, lead and arsenic concentrations in liver of L. klunzingeri were higher than their levels in muscle. In this study, there was no significant positive correlationbetweenconcentration of Hg, Cd, Pb and As with length and weight in muscle of Liza klunzingeri (P<0.05).Accumulation ofHg, Pb and As in muscle of Liza klunzingeri was lower than the WHO, FDA and NHMRC standards, but concentration of Cd was higher than the NHMRC standards.

This study was done in order to determine the concentration of heavy metals Nickle, Cadmium and Lead in the muscle of Acanthopagrus latus and Platycephalus indicus from Oman Sea (Chabahar Bay) in spring, summer and fall of 2013. In this study 48 samples of fishes were obtained from coastal and marine regions of Oman Sea (Chabahar Bay). Metals were extracted from the tissues using wet digestion method and concentration of heavy metals were measured by Younglin AAS8020 Atomic Absorption Spectrophotometer. The highest concentration of Cd, Pb and Ni were found in the muscle of Platycephalus indicus which were 0.052±0.02, 0.047±0.02 and 1.768±0.96 mg kg-1. The lowest concentration of Cd, Pb and Ni were obtained in the muscle of Acanthopagrus latus which were 0.019±0.01, 0.010±0.01 and 0.466±0.02 mg kg-1. Concentration of Cd, Pb and Ni in the two fishes from coastal zone was higher than marine area. Concentration of heavy metals in the muscle of Acanthopagrus latus and Platycephalus indicus in summer was higher than spring and fall. Concentration of Ni in the two fishes was higher than Cd and Pb. Concentration of Cd and Pb in the muscle of Platycephalus indicus from coastal and marine zone in spring, summer and fall was higher than Acanthopagrus latus, but concentration of Ni in the muscle of Acanthopagrus latus was higher than Platycephalus indicus. Concentration of Cd and Pb was lower in comparison with levels recommended by FAO, WHO, UKMAFF, NHMRC and FDA, but concentration of Ni was higher in comparison with international standards.

This study evaluated and compared the accumulation of Ni in the muscle tissue of fish Cobia (Rachycentron Canadum) and its relation to total length, total weight and age of the fish in the waters of the northwest of Persian Gulf in 2014. Ninety six fish samples were collected at 6 length groups. To measure the level of essential elements, the samples were digested by wet digestion method and by Perkin Elmer 4100 AAS instrument. The means were compared using analysis of variance (ANOVA) and correlations and significant differences were estimated at 95% significance level. Mean concentration of Ni in the muscle tissue of Rachycentron Canadumwas 0.148±0.05 mg/kg dry weight (P<0.05). The highest concentration of Ni was found in the group with larger than 127 cm length (0.238±0.9 mg/kg dry weight). A positive correlation was established between the total length and total weight and age and accumulation of Ni at P. Concentrations of Ni in muscle of Rachycentron Canadum were lower than international standard of WHO (0.38 mg/kg).

This study was carried out to determine the heavy metal content ( Pb and Cd) in muscle and liver tissues of Pomadasys kakaan   in Bandar Abbas during winter 2011 and summer 2012. After biometry of the fish, muscle and liver tissues were separated. The amount of Pb and Cd were measured by atomic absorption spectroscopy (Varian model GTA 100). Based on the results, the average concentration of Pb and Cd in liver tissues were observed to be 0.1334±0.0234 and 0.0255±0.0077 µg/g respectively and in muscle tissues 0.0439±0.0106 and 0.0041±0.0007 µg/g, respectively. The difference between the average concentration of Pb and Cd in liver and muscle tissues is significant (P<0.05). Average accumulation of Pb and Cd in liver and muscle tissues were not difference significantly between two seasons (P>0/05). The comparison of the results with permissible limits of WHO and EPA showed that the concentrations of these metals are low.

gbbggbThis study was conducted to determine and comparetrace elements, Fe, Zn and Cu in muscle of 8 species of endemic fish, Barbus grypus, Barbus sharpeyi, Barbus xanthopterus, Barbus pectoralis, Carasobarbus luteus, Liza abu, Barbus esocinus and Aspius vorax, in 2012.Seventy two samples of fishes were collected from Horolazim wetland in Khuzestan province.Concentration of heavy metals, following wet digestion,were measured by Perkin Elmer 4100 atomic absorption spectrometer. Data were analyzed by ANOVA using SPSS17 software at significant level of 5% (P=0.05). Concentration of Fe in muscle of fishes were not significantlydifferent (P>0.05). The zinc content in muscle of Barbus grypuscompared to other fishes were significantly different (P<0.05). Copper levels in muscle of fishes studied were significantly different (P<0.05). The mean concentration of Fe, Zn and Cu in muscle of fishes were 11.39±0.26, 12.94±0.38 and 0.62±0.004 mg kg-1, respectively. Also, the highest concentration of Cu was calculated in muscle of Barbus xanthopterus (mg Kg-1). The average concentration of Zn and Cu in muscle of fishes were lower than WHO permissible levels.

The aim of this study was to evaluate the heavy metals (nickel and lead) that has accumulated in Litopenaeus vannamei in vicinity of two types dispersants, Naft roob (Iranian dispersants) and Radiogreen OSD (foreign dispersant). For this study, a control group and 5 treated with different concentrations and combinations and each with three replications were considered. Shrimp samples exposed to crude oil and combination of crude oil and two dispersants for 48 hours. The accumulated heavy metals were then measured by atomic absorption spectrometry. Results showed that the highest average concentration of nickel in shrimp, was found to be in the combined treatment of Naft roob at 4.484 ppm,. The highest average concentration of Pb was found in L. vannamei, which was exposed to foreign oil dispersant, Radiogreen OSD, at 2.443 ppm. Finally, it was found that by increasing crude oil and dispersant concentration, higher levels of heavy metals were absorbed by the shrimp in vicinity of crude oil and crude oil combined with dispersants. Nickel was also found to be accimulated at much higher concentrations compared to lead in shrimp exposed to crude oil and crude oil combined with dispersants.

This research intends to study the rate of accumulation of heavy metals and calculate the rate of pollution of seabed sediments in sampling and analyses as a result of large industrial activities in Asaluyeh region. The in Asaluyeh region in the Persian Gulf, due to its exceptional position, where a great number of gas refineries and petrochemical plants are established, is directly or indirectly exposed to different organic and mineral pollutants. Taking into consideration the position of the region, this study was conducted in 2013 in 10 stations, to study the pollution resulting from the heavy metals of Cobalt, Cadmium, Lead, Nickel, and Mercury. Sediment samples were collected by Ekman Grab and measurements were made by a furnace atomic absorption device. Furthermore, the obtained data were modeled with fuzzy logic. The comparison of the results obtained from modeling with the data resulting from lab measurements, indicates the suitable efficiency of fuzzy logic in forecasting the quantities of heavy metals density.

This study was undertaken during 2013 on the barracuda fish Sphyraena sp. caught from waters of Bandarabbas.This project focuses on concentration of heavy metals in muscle and liver tissues of this fish. In addition results were compared with the international standards.The muscle and liver tissues of 20 samples catched and separated. Metals were extracted from muscle and liver tissues using acid digestion method (ASTM). Concentrations of heavy metals were measured by ICP. Mean concentration for Zn , Cu , Pb and Cd in the muscle tissue 2.675±0.800, 0.385±0.658, 0.325±0.169 and 0.087±0.012 ppm and liver tissue 11.850±3.943, 4.957±1.632, 0.485±0.2406 and 0.480±0.2402 ppm (as fed) respectively. Results compared with international standards such as WHO, FAO , UK (MAFF) and lower concentration of all metals in muscle and liver tissues except concentration of Cd in liver tissue from the above standards was concluded and they didn’t have significant difference between Pb , Zn , Cu in muscle tissue (P≥0.05) ,but there was Cd in muscle tissue during the 2013 (P<0.05).

A comparative study was conducted on composition of protein, lipid and ash and concentration of metals As, Hg and Cd in muscle of Cynoglossus arel from Hendijan area in 2011. Ten samples of Cynoglossus arel were collected using trawl net. Concentration of Hg, As and Cd in the muscle of flat fish was 41.60±7.27, 73.30±7.50 and 189.02±21.40 µgkg-1 ww. Also composition of protein, lipid and ash in the muscle of this fish was determined; 16.58±0.54, 1.04±0.14 and 1.57±0.13 %. Comparison of the results showed significant difference between (P<0.05) concentration of Hg, As and Cd in the muscle of Cynoglossus arel. The highest correlation (R=0.964, P<0.05) was observed in the muscle of Cynoglossus arel between to Cd and As. In this study significant correlation was observed between concentration of Hg, As and Cd with chemical compositions, in the muscle of Cynoglossus arel (P<0.05). The highest correlation (R=0.972, P<0.05) was observed in the muscle of Cynoglossus arel between to As and protein. Also the lowest correlation (R=0.880 P<0.05) was observed in the muscle of Cynoglossus arel between to Hg and protein.

Ten specimen of Vimba vimba persa fish were caught using a bach seine net by local fishermen in December 2013 from the Anzali coasts (Anzali Wetland openings). Samples were transferred to the laboratory and then the fish gender was determined. Biometry of each was done. Samples consisted of 6 female and 4 male. Average length of females and males were 19.21 ± 1.01 and 18.65±0.264 cm respectively and the average weight of females and males were 68.8± 8.160 and 62.9±2.201 gr respectively. Then, 1 gram of every fish muscle was separated and Al, Ni, Cr, Pb were measured in the muscles after chemical digestion using ICP. Hg measurement in muscles was done by atomic absorption using cold vapor method. Each treatment had 3 replicates. The amount of metals in both females and males was as follows Al> Ni> Pb> Hg> Cr. Significant differences between the concentrations of these metals were not observed in both males and females (P≥0.05). By comparing the concentration of studied heavy metals with international standards (WHO, FAO, SAW, FEPA) showed that mercury levels in males and females were 0.22± 0.05 and 0.20±0.06 milligram in kilogram respectively (WHO=0.1-0.5), chromium in both sex was less than 0.01 milligrams in kilogram (WHO=0.15) and lead in males was 0.85± 0.44 and in females were 0.58± 0.36 milligram in kilogram (WHO= O/5-1/5) and each 3 metals were less than the international standard levels. The concentration of Aluminum in males was 1.95±0.51 and in females was 1.23±0.59 milligram in kilogram (SAW=0/03) and Nickel was 1.60±2.00 and 0.766± 0.18 milligram in kilogram in males and females respectively (WHO=0.5-0.6), which exceeded of international standards.

Anzali Lagoon is an internationally protected lagoon located in west-south of Caspian Sea which has special ecologic, economic, social importance with vast diversity of plants and animals. According to entrance of contaminants into this lagoon, concentration of several heavy metals in muscle of Esox lucius fish have been investigated in this study. First stage of sampling from three stations of lagoon, have been fulfilled at dry season of September and second stage have been implemented at rainy season of November 2010. In each season nine samples of fish have been collected and transported to laboratory in freezed condition. Evaluation and measurement of heavy metal concentration has been fulfilled by Graphite furnace atomic absorption equipment. Maximum mean concentration of Hg, Ni, Se, Zn, Al, and Fe have been detected in the summer and maximum mean concentration of Cu has been detected in the winter. Maximum mean value of Hg, Ni, Zn,Al in Abkenar, maximum mean value of Se in Siah Darvishan and maximum mean value of Cu, Fe in Komeh Aghajani have been detected, while concentraton of Mo, Cd, V and Pb are equal in the three above mentioned stations. Statistical analysis of this study has been fulfilled by SPSS, V14 software. Pearson correlation test, showed a positive strong correlation between temperature and the amount of Fe (r=0.83, P<0.05). Only significant difference in concentration of Fe has been obtained between summer and winter seasons (P=0.016, df=16, P<0.05). Significant difference in concentration was detected only for Hg between Abkenar and Komeh Aghajani stations (P=0.05).This study shown that, the concentration of Ni, Hg, and Cd in the muscle of Esox lucius are high and it is considered as a serious warning.

To determine the heavy metals Zinc, Lead, Chromium and Copper in soft tissues of Thais mutabilis (gastropod) in three transect of tidal coast of Bandar Abbas, sampling was done in winter of 1389 (2011). Each Transect had three stations; Upper, mid and lower tidal zone. Sampling was done randomly with 0.5 square meter quadrate. Each area was sampled 9 times. The samples were analyzed for determination of heavy metals (Zn, Pb, Cr, Cu). The results showed that in the gastropod, zinc (577/18 ±438.9 ppm) was at the highest concentration between the heavy metals and Lead (0/17±0/6 ppm) was at the lowest. Generally, the highest concentration of Zinc (9/438±18/577), Lead (8/0±67/0) and Chromium (8/0±23/1) in soft tissues of gastropod was in Golshahr jonobi station, and the highest concentration of copper (6/134±77/88) was in the Posht shahr station. Statistical analysis showed that there was a significant difference (P≤0/05) in the concentration of chromium metal in soft tissue of gastropod in Golshahr jonobi transect with Soro. However, there is no significant difference between the concentrations of lead, copper and zinc in samples of soft tissue of gastropod in each transect (P≥0/05). The concentration of lead and chromium in this aquatic environment is lower than admissible range (WHO, 1985). It shows that the input of pollution containing these metals to this environment is low. The concentration of heavy metals such as zinc and copper is higher than admissible range (WHO, 1985) in every 3 transect. The result of bioaccumulation of heavy metals (Zink, Lead, Copper, and Chromium) in soft tissues of Thais mutabilis (Gastropoda) exhibited the following order: Zn> Cu> Cr >Pb.

Recently, the ecology of the Caspian Sea has undergone with increasing development of human activities and industrial wastewater discharges. Heavy metal compounds are undegredable pollutants and are able to accumulate in the environment. They can affect the food chain and biological individuals such as fish species. 40 and 22 samples of Rutilus frisii kutum and Liza saliens were collected in central and eastern parts of southern Caspian Sea in 2008, respectively. All samples were analyzed based on standard methods using Atomic Absorption instrument (Thermo, M5 model). Results of this study showed that the amount of Zn in fish muscle of L. saliens was maximum (415.3±196.3 µg/g. dw). The concentrations of Cu, Ni, Pb, Cd and Hg in fish muscle of L. saliens were 10.85 ±11.02, 0.41 ±0.84, 2.63 ±2.67, 0.63 ±1.07 and 1.30 ±0.16 µg/g. dw, respectively. The concentrations of Cu, Ni, Pb, Cd and Hg in fish muscle of R. frisii kutum were 0.40 ±0.46, 0.0132 ±0.007 and 1.26 ±0.75 µg/g. dw, respectively. 7 heavy metals were below the established limits of different countries. The pearson correlation analysis showed that between Zn and Hg there were a significant negative correlation indicating a decrease of Hg toxcicity with increasing Zn concentration. THQs for individual metals were lower than USEPA guidelines value of 1 in young and adults human. Thus, consumption of 6 kg R. frisii kutum and/or L. saliens per capita cannot be risky for young and adults consumers.