The aim of this study was to determine the concentrations and degree of metals contamination (Chromium, Cadmium, Nickel and Lead) and Arsenic in the soils of the three Industrial Estates in Arak city, Iran. The average concentrations of Arsenic, Chromium, Cadmium, Nickel and Lead were 5.06, 1.26, 37.13, 67.84 and 60.22 mg kg(-1), respectively. Pearson correlation indicated that Arsenic, Cadmium and Lead were mainly derived from anthropogenic inputs, and Chromium and Nickel were controlled by natural source, whereas Nickel appeared to be affected by both anthropogenic and natural sources. The geo-accumulation Index (Igeo) calculated in three industrial estates gave values indicating unpolluted to strongly polluted.
Levels of arsenic (As), cadmium (Cd), cobalt (Co), lead (Pb), nickel (Ni), selenium (Se), and vanadium (V) were evaluated in coastal sediments, egg contents, and eggshells of crab plover (Dromas ardeola), bridled tern (Sterna anaethetus), lesser crested tern (S. bengalensis), and western reef heron (Egretta gularis) breeding in the northwestern Persian Gulf. Levels of Cd, Pb, Ni, V, and Se were greater in eggs of terns than in eggs of crab plover, perhaps due to the higher trophic level of terns. Levels of all elements were lower than known effects levels for birds. However, levels of Se in eggs were greater than those known to cause toxic effects in birds. Eggs of terns are ideal for monitoring metal contaminants on the breeding grounds because the bioaccumulation ratios (egg/sediment) of some metals (As, Co, Se) in the eggs of terns are significantly greater compared with those of crab plovers.
This study assessed the baseline concentrations and spatial distribution of total mercury (Hg) in urban soils of the city of Arak, Iran. Concentrations of Hg were determined in soil collected from urban areas, and the spatial distribution was analyzed using the semivariogram approach in geostatistical technology. Mercury in soil ranged from 66.3 to 581 µg/kg. The experimental variogram of soil mercury concentrations was best-fitted by a spherical model. A spatial distribution map revealed that Hg concentration showed decreasing trends from south to north, west to east and center to suburb. Overall, the results showed that Hg concentrations in urban soils of Arak may be considered medium or low.
To determine the extent of oil contamination and biodegradation in Anzali Wetland of Iran, we examined aliphatic hydrocarbons in surface sediment of this area (n=20). Petroleum hydrocarbon levels (mean 1585 ± 1117; range 316 to 4358 μg g- dry weight) were similar in value to reports from other highly contaminated areas, such as New York Bight, Saudi and Kuwaiti coasts of the Persian Gulf, and Dubai shorelines. Even carbon homologs dominated distribution of n-alkanes in surface sediment of Anzali, which is rarely reported elsewhere. Multiple factors used in our study point to petrogenic source for n-alkanes in Anzali Wetland. Anzali receives multiple industrial and agricultural runoffs from the surrounding area. Shipping industry and oil industry are responsible for a major portion of pollutants entering Anzali. Municipal wastewater discharges are another source of Anzali pollution. To determine why even carbon number n-alkanes predominate in Anzali, we examined the following indices: existence of unresolved complex mixtures (UCM), ratio of UCM to resolved alkanes (RA), ratio of low-molecular weight to high-molecular weight molecules, presence of degraded oil residue, high-relative biodegradation, and the degree of hydrocarbon weathering in the surface sediment of the area. Our findings corroborate with such predominance.
This study is the first detailed ecotoxicological study of the annulated sea snake, Hydrophis cyanocinctus. Concentrations of lead, cadmium, nickel and vanadium were evaluated in muscle, liver, kidney, skin and blood of the annulated sea snake (H. cyanocinctus) and in the whole bodies of its main prey species (Periophthalmus waltoni and Boleophthalmus dussumieri) in the Hara Protected Area, the Persian Gulf. The mean concentrations of lead and vanadium were highest in the kidney, which identified the kidney as a target organ for metals in sea snakes as it is in other reptilian groups. Mean concentrations of cadmium and nickel were highest in the liver and skin, respectively. Mean cadmium concentrations were significantly higher in the liver compared to prey species, which indicated that prey items may be a source of cadmium for the annulated sea snake in the study area. Data presented here may be considered as a baseline for further ecotoxicological studies in sea snakes.
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