Enzymatic and histopathologic biomarkers in the flatfish Euryglossa orientalis from the northwestern Persian Gulf.

Most of the chemicals in the petrochemical sewages cause oxidative stress in marine organisms. Antioxidant enzymes (catalase (CAT) and superoxide dismutase (SOD)) as biomarkers of oxidative stress and liver histopathological alterations were investigated in the current study to evaluate the toxic effects of petrochemical pollutions in flatfish, Euryglossa orientalis The enzymatic and histopathological changes were assessed in the liver of E. orientalis from Khowr-e Jafari (one of the creeks from Khowr-e Musa estuary) and Sajafi harbor as polluted and clean areas, respectively. A significant increase in the antioxidant enzyme activities was observed in response to aquatic pollutions of Khowr-e Jafari. Liver lesions were diagnosed and categorized using standard methods. The results of histopathological examinations showed more lesion scores in the fish from Khowr-e Jafari. Various histopathological changes including hepatocyte degeneration, inflammatory lesions, peliosis hepatis and pancreatic acinar cell adenoma, and increase in the number of pigmented macrophage aggregates were observed in the fish from polluted site. It is suggested that activities of CAT and SOD along with semi-quantitative histopathologic analysis of E. orientalis can be used for biomonitoring programs in Persian Gulf.

Combining biological and geomorphological data to introduce biotopes of Bushehr Province, the Persian Gulf.

Identification and classification of intertidal areas provides the basic knowledge needed for studies of biogeography, macro-ecology, and faunal populations, as well as for conservation planning and managing human activities in coastal areas. In this research, the eastern coast of Bushehr Province was classified using the Coastal and Marine Ecological Classification Standard (CMECS). Seven substrate subgroups, five geoform types in unconsolidated mineral substrate, five micro-habitats in rock substrate, and nine biotic groups were identified in study stations. The non-metric multidimensional scaling (nMDS) ordinations and one-way analysis of similarity (ANOSIM) showed that macroinvertebrate species composition differed significantly among different geoform types (habitat types). Eight biotopes are introduced for the eastern coast of Bushehr Province based on observational and statistical methods. The results presented here show that identifying intertidal biotopes using CMECS is an appropriate method both for classifying the southern coastal areas of Iran and for integrating biotic and abiotic components.

Application of biomarkers in Epaulet grouper (Epinephelus stoliczkae) to assess chromium pollution in the Chabahar Bay and Gulf of Oman.

In the present study plasma levels of erythropoietin (EPO) hormone and kidney histological changes were assessed as biomarkers to evaluate the chromium pollution in Epaulet grouper (Epinephelus stoliczkae) obtained from different areas in Chabahar Bay and Gulf of Oman. Chemical analyses included the evaluation of chromium in the fish kidney tissue and sediment. The highest and lowest concentrations of chromium were measured in the kidney of fish and sediment collected from Konarak (47.53±1.23 and 110±1.4 µg g(-1)) and the mouth of Chabahar Bay (3.43±1.31 and 13.5±3.23 µg g(-1)), respectively. There was significant difference (P<0.05) of EPO plasma levels between Konarak, Beris and Ramin stations with the mouth of Chabahar Bay as the cleanest station. Reduction of Bowman's space, occlusion of the tubule lumen, leukocytes infiltration, melanomacrophage centers aggregation, nuclear vacuolation, nuclei hypertrophy of tubule cells, necrosis of the tubules, lifting of the tubular basement membrane and dilatation of glomerular capillaries were the most alterations observed in the kidney. The HAI values of Epaulet grouper from Konarak, Beris and Ramin stations were significantly higher than other stations (P<0.05). It was concluded that selected biomarkers as a first investigation could be useful tools to environmental biomonitoring programs.

Heavy metals' concentration in sediment, shrimp and two fish species from the northwest Persian Gulf.

The concentrations of heavy metals (cadmium (Cd), copper (Cu), nickel (Ni), lead (Pb) and zinc (Zn)) were measured in hepatopancreas and muscle of a commercial shrimp (Metapenaeus affinis), in the muscle, liver and gills of two fish species (Thryssa vitrirostris and Johnius belangerii) and in the sediment samples taken from the mouth of the Arvand river, Meleh estuary and Musa estuary in the northeast Persian Gulf. Concentration of heavy metals varied depending on different tissues, species and sampling sites. Liver of fish and hepatopancreas of shrimp exhibited higher metals' concentration than the other tissues. Generally, in the mouth of the Arvand river, the highest concentration of metals was found in benthic species; while in the mouth of Musa estuary, the highest level of the metals was found in pelagic fish species. Bioaccumulation factors were observed to follow the order: J. belangerii-liver-Cd > T. vitrirostris-liver-Pb > M. affinis-hepatopancreas-Zn >M. affinis-hepatopancreas-Cu >M. affinis- hepatopancreas-Ni. The analysed heavy metals were found in sediment samples at mean concentration in the sediment quality guideline proposed by National Oceanic and Atmospheric Administration (NOAA) and Regional Organization for the Protection of The Marine Environment (ROPME), except for Ni concentration in some cases.

An assessment of hematological and biochemical responses in the tropical fish Epinephelus stoliczkae of Chabahar Bay and Gulf of Oman under chromium exposure: ecological and experimental tests.

The aim of this investigation was to evaluate the effect of chromium on hematological and biochemical parameters in Epaulet Grouper, Epinephelus stoliczkae of Chabahar Bay and Gulf of Oman by ecological and experimental tests. Spatial evaluation of ecological test results showed these parameters had significant difference among some sampling sites. Examination of hematological and biochemical profiles on Epaulet Grouper was performed after 0.5, 1, 7, 14, and 21 days of chromium exposure (3.6, 7.31 and 14.6 mg/L). Experimental test results of chromium induce indicated the significant decrease in MCV, MCH, neutrophils, basophils, plasma protein and significant increase in MCHC, lymphocytes, monocytes, eosinophils and a biphasic trend in Hb, Ht, RBC, WBC, and glucose (p < 0.05). Cellular and nuclear axis, cytoplasmic volume, cell and nuclear volume, and surface area were significantly different for ecological and experimental results (p < 0.05). It was concluded that these parameters are sensitive in monitoring the toxicity of chromium concentrations.

Assessment of gill pathological responses in the tropical fish yellowfin seabream of Persian Gulf under mercury exposure.

Gill histomorphological alterations were used to assess the effects of chronic exposure to HgCl2 on the yellowfin seabream, Acanthopagrus latus. In this regard, 90 A. latus were exposed to sublethal concentrations of HgCl2 (10, 20, 35 and 50 µg/L) for 3 weeks. Treated fish were erratic and showed respiratory distress. The most common morphological abnormalities included: filaments disorganization, increase of mucus secretion, debris and blood plaques on the filaments, losing or shortening of some filaments. The most frequent histopathological changes detected in the gills included extensive lifting of the lamellar epithelium and edema of lamellae with enlarged sub-epithelial spaces, exfoliated epithelium of lamellae, telangiectasia, hypertrophy and hyperplasia of the epithelial cell resulted in partial fusion of the secondary lamellae and a reduction of the water space, club shaping of gill lamellae, blood congestion. Some more severe alternations found in the gill of fish exposed to higher levels of HgCl2 (35 and 50 µg/L) included lamellar aneurysm and hemorrhages with rupture of the lamellar epithelium. According to the results of the present study, mercuric chloride could cause major histomorphological changes in the gill of A. latus, decreasing its gas exchange capability. Two mercury concentrations (10 and 20 µg/L) used in the present study were in agreement with the concentration of mercury in the water of different parts of Mahshahr creeks (the north of Persian Gulf) (3.66 to 15 µg/L). Therefore, based on the results the presence of pathological alteration in A. latus inhibited in the natural environment (Mahshahr creeks) seems to be logical.

The relationship between heavy metal (Cd, Co, Cu, Ni and Pb) levels and the size of benthic, benthopelagic and pelagic fish species, Persian Gulf.

The concentration of heavy metals was determined in tissues of sole (Euryglossa orientalis), mullet (Liza abu) and croacker fish (Johnius belangerii) from Musa estuary. Generally, the highest concentration of the studied metals in the three species was found in the liver tissue. The levels of Cd and Cu in fish liver were J. belangerii = E. orientalis > L. abu and E. orientalis > L. abu > J. belangerii respectively. The concentrations of Cd and Cu in fish gills were E. orientalis > L. abu = J. belangerii and E. orientalis > L. abu > J. belangerii, respectively, and the level of Cu in muscle was E. orientalis > L. abu = J. belangerii. The results of linear regression analysis indicated that highly significant (p < 0.001) negative relationships were found between fish size and Cd concentrations in the liver of L. abu and Pb in the gills of J. belangerii.

Contamination levels and spatial distributions of heavy metals and PAHs in surface sediment of Imam Khomeini Port, Persian Gulf, Iran.

Imam Khomeini Port (IKP) is the largest Iranian commercial port. Because of many petrochemical industries and urban areas are located around this port and also having heavy ship traffic, concentrations of PAHs, mercury and other heavy metals were measured as the first time in surface sediment of the jetties. The highest concentrations of PAHs, Hg, Cu, Pb and Fe were recorded at Site 1, located in the vicinity of the petrochemical industrial zone, where ships are repaired. The highest concentration of Zn was found at Site 4, which is the jetty for loading mineral materials. The comparison between measured values in this study and some sediment quality guidelines indicated that the concentrations of mercury and PAHs are much higher than other studies. Also, the ratios of PAHs in the stations showed a mixture of both of pyrolytic and petrogenic sources with a dominance of pyrolytic sources.

Heavy metal concentration in sediment, benthic, benthopelagic, and pelagic fish species from Musa Estuary (Persian Gulf).

The concentration of Cd, Co, Cu, Ni, and Pb was measured in sediment and three fish species collected from Musa Estuary, Persian Gulf. The concentration order of heavy metals in sediment were Ni > Co > Cu > Pb > Cd >. Concentrations of the heavy metals in the fish were apparently different among the three species. The concentrations of Cd and Ni in fish were Johnius belangerii > Euryglossa orientalis > Liza abu, while the Co and Cu levels were L. abu > E. orientalis > J. belangerii and E. orientalis > L. abu > J. belangerii, respectively. Result of regression analysis showed that there were no significant relationships between metal concentration in fish tissues and sediment, except for Ni concentration in the J. belangerii liver. The concentrations of studied metals in fish muscle were below the permissible limits proposed by FAO, WHO, and EC.

Using histopathological changes as a biomarker to trace contamination loading of Musa Creeks (Persian Gulf).

Gill histological changes were used as a biomarker to evaluate the health of yellowfin seabream, Acanthopagrus latus (A. latus), collected from different sites in Musa Creeks including: (A) Petrochemical, (B) Jaafari, (C) Ghazaleh, (D) Majidieh, and (E) Zangi creeks. Also Genaveh with relatively clean water was selected as reference. The gills of 60 A. latus were fixed in Bouin's solution for 12 hr, dehydrated in a graded series of ethanol, and embedded in paraffin. Five micrometer thick sections were stained in H&E and Periodic Acid Schiff for microscopic examination. Also, the presence of gill histological alterations was assessed by the histopathologic alteration index (HAI). The gill morphological abnormalities include mucus secretion increase, debris, blood plaque, and shortening of filaments. The gill pathological changes included lamellar cells hyperplasia, aneurysm, lamellar fusion, and epithelial lifting. The HAI means were varied from moderate to severe in sites A and B, thus these sites are considered as being of low quality. Some severe pathological alterations were observed in site D, but their distribution was lower than sites A and B. The least HAI means of sites C and E demonstrated their good environmental quality. The results suggest that there is close relation between amounts of pathological alterations and environmental contamination.

Effect of sublethal dose of mercury toxicity on liver cells and tissue of yellowfin seabream.

The aim of the present study was to provide baseline data on the prevalence of histopathological liver lesions in Acanthopagrus latus under experimental mercury exposure. Experimental study was at seawater recirculatory tanks. Mercury concentrations were determined using a standard cold vapour atomic absorption. Histopathological analyses were done in tissue processor and the slides were stained with haematoxylin and counterstained with eosin. There were many liver lesions including enlarged and lateral nuclei, nuclear degeneration and vacuolation; oncotic, apoptic, focal, massive, centrilobular and periportal necrosis; atrophy, lipidosis, hydropic and cloudy swelling, oval cell proliferation; bile stagnation, dilation of sinusoid, intracellular oedema and dark granules in both field and laboratory conditions. In conclusion the present investigation indicated that mercury is a toxic substance in yellowfin seabream and the sublethal concentrations of mercury may cause several changes in the histological indices of the studied fish, and we can use these changes as biomarkers of mercury detection.