Analysis of PAHs content, source identification and ecological risk assessment in surface sediments from the Caspian Sea.

The concentrations of Polycyclic Aromatic Hydrocarbons (PAHs) in surface sediments were investigated in the southern Caspian Sea. The results revealed that the total PAHs in sediments varied from 6.53 to 170.

Origin and comprehensive risk assessment of heavy metals in surface sediments along the Caspian Sea.

Metal concentrations (Cu, Zn, Cr, Fe, As, Pb, Ni, V, and Co) in surface sediments were determined in the southern Caspian Sea. Sediment pollution was investigated using geochemical index such as Enrichment Factor (EF) and ecological risk indices like modified Hazard Quotient (mHQ) and Toxic Risk Index (TRI). The highest calculated geochemical index was observed in sediments near the cities of Chalus and Ramsar, which are highly polluted due to human activities.

Biomarkers for monitoring heavy metal pollution in the Anzali Wetland.

This research aims to investigate biochemical activities of Phragmites australis, as a biomarker of heavy metals including Cr, Ni, V, Zn and Co. In order to determine and analyze biochemical parameters including flavonoids, Non-Protein Thiols (NPTs), chlorophyll a and b and total chlorophyll pigments in the roots, stems and leaves of P. australis, sediment and plant samples were collected from 7 stations in the Anzali wetland.

Contamination and ecological risk assessment of trace elements in sediments of the Anzali Wetland, Northern Iran.

In this paper, concentrations of some heavy metals in surficial sediments of the International Anzali Wetland were measured, this wetland is located in the northern part of Iran. Sediment pollution levels were examined and analyzed using reliable pollution indices including Pollution Load Index (PLI), Geoaccumulation Index (Igeo) and Enrichment Factor (CF), and finally it was revealed that heavy metal pollution ranged from low to moderate loads in the wetland. According to Sediment Quality Guidelines (SQGs) and Ecological Risk Index (ERI), it was concluded that As and Ni may have significant toxic impacts on aquatic organisms and also according to Effect Range Median (ERM), the toxicity probability of sediments in the Anzali wetland was estimated at 21%.

Heavy metal pollution status in surface sediments of the Khajeh Kory River, north Iran.

This study aimed at exploring the extent of likely sources of heavy metal pollution in sediments of the Khajeh Kory riverbed in the north of Iran. In order to assess the heavy metal contamination, samples from surface sediments in 10 stations covering the river were collected and analysed to determine heavy metal contents including Cd, Cu, Ni, Pb, Zn, Mn, Co, Al, and Fe. Three guidelines were applied to assess the heavy metal contamination.

Assessment of Heavy Metal Pollution and Human Health Risks Assessment in Soils Around an Industrial Zone in Neyshabur, Iran.

Heavy metal pollution of soils in industrial zones continues to attract attention because of its potential human health risks. The present research is an attempt to assess the pollution status of heavy metals including As, Cd, Cr, Ni, and Pb using various indices like contamination factor (CF), pollution index (I), and geo-accumulation index (I). In total, 60 surface soil samples were collected from four area (north, south, east, and west) in Khayyam industrial zone from depths of 10-20 cm.

Evaluating of heavy metal pollution in Amir-Kalayeh wetland using geochemical and statistical analyses.

Metal pollution in aquatic ecosystems has created concern due to its toxicity, environmental stability and ability to transfer into the food chain, and monitoring the metal source is one way to decrease the environmental impact. The present study aimed to investigate metal concentrations of Al, Fe, Mg, P, As, Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb, V and Zn, their spatial distribution, origin of the contaminants, contamination factor (CF), pollution load index (PLI), enrichment factor (EF), and geoaccumulation index (I) in surface sediments of the Amir-Kalayeh wetland. Using statistical methods such as Pearson correlation coefficient, cluster analysis and factor analysis, the natural or anthropogenic origin of these elements was determined.

Bioavailability and geochemical speciation of phosphorus in surface sediments of the Southern Caspian Sea.

The purpose of this study was to quantify phosphorus bioavailability and various forms of this element in surface sediments of the southern Caspian Sea. To do, sediment samples were collected from different depths in autumn 2015 using a Van Veen Grab. Phosphorus forms were recognized by a sequential extraction procedure (SEDEX).

Antioxidant response to metal pollution in Phragmites australis from Anzali wetland.

This research was conducted to examine variations of antioxidant enzyme activity in Phragmites australis as a biomarker for metals such as As, Pb, Cu, and Cd. Samples of sediment and plants were collected from 7 stations located in Anzali wetland. Biochemical parameters including Catalase, Peroxidase and Ascorbate Peroxidase activity were analyzed in the roots, stems and leaves of P.

Geochemical speciation, bioavailability and source identification of selected metals in surface sediments of the Southern Caspian Sea.

Geochemical speciation of As, Cd, Co, Cr, Cu, Ni, Pb, V and Zn were determined in the surface sediments of the southern Caspian Sea. A five-step sequential extraction technique was used to determine the chemical forms of metals. Mean concentrations (ppm) of heavy metals were (mean±S.

Geochemical speciation and ecological risk assessment of selected metals in the surface sediments of the northern Persian Gulf.

The present study aimed to geochemical speciation of metals in the surface sediments of the northern Persian Gulf. Metal contents in the sediment were observed in the order: Al>Fe>Cr>Ni>V>Zn>Cu>Co>As>Pb>Cd. The results of sequential extraction procedure revealed that all metals were predominantly associated with the residual fraction.

Heavy metal accumulation in tissues of two sea cucumbers, Holothuria leucospilota and Holothuria scabra in the northern part of Qeshm Island, Persian Gulf.

The concentrations of some heavy metals (Cd, Cu, Zn andPb) were investigated in the sediments and the two species of sea cucumber (Holothuria leucospilota and Holothuria scabra) from northern part of Qeshm Island, Persian Gulf. The levels of Cu, Zn and Pb in sediment varied significantly among sampling sites (p<0.05).

Bioaccumulation and ecological risk assessment of heavy metals in the sediments and mullet Liza klunzingeri in the northern part of the Persian Gulf.

The concentrations of some heavy metals (Cu, Zn, Pb and Cd) were investigated in the sediments and in the mullet Liza klunzingeri from the northern part of the Persian Gulf. The levels of Cu, Zn and Pb in the sediment varied significantly among the sampling sites (P<0.05).