مجله علوم و فنون دریایی
سال دهم شماره 3 (پاییز 1390)

The present study carried out to assess the effects of Benzo-α-Pyrene (BaP) as a serious member of Polycyclic Aromatic Hydrocarbons (PAH) on the plasma levels of cortisol and triiodothyronine (T3) hormones in male Seabream, Acanthopagrus latus (Sparidea). To assess the acute effects of BaP on the endocrine system, a group of fish was injected with dissolved BaP in sunflower oil (50mg/kg BaP in 2µg/l oil according to the body weight). Other fishes were injected with 2µg/l body weight as controls. Blood samples from both groups collected 3 hours after injection. In another protocol, the chronic effects of BaP on the plasma levels of cortisol and T3 were assessed. For this reason a group of fish was implanted with 50mg/kg BaP in 10µl/g coconut oil in respect to each fish body weight. As the previous protocol a control group was implanted with the same amount of oil without the BaP. Blood samples collected from both implanted groups (treatment and control) after 72 hours. According to the results, plasma levels of cortisol in yellowfin Seabream increased during both short time and long time exposure but T3 levels in the plasma decreased during the chronic stress of BaP exposure. It seems the cortisol levels are elevating to provide more energy requirement under the acute and chronic stress conditions by direct effect on glyconeogenesis and fast blood sugar level to be consumed by cells. T3 levels may be affected by inhibitory effect of Aryl hydrocarbon receptors (AhRs) which decreased it during long term exposure.

For this survey, eight stations were selected in the Anzali Lagoon based on vicinity to the urban area, agricultural fields, in lets and out lets of the rivers. Sampling was carried out seasonally and in each season triplicate water samples were taken from surface layer of each station. Totally 96 water samples were collected during one year period in sterile condition.Samples were transferred to the laboratoray at 4ºC temperature using ice box. The pollution by Coliform was examind using standard technigue of MPN and for count of bacteria differential, specific test and pourplate method isolate was used. In this survey different genus of bacteria were isolated and identified as: E.Coli (%19.65), Shigella (%18.21), Klebsiella (%17.86), Proteus (%13.21), Enterobacter (%11.07), Morganella (%9.65), Salmonella (%3.92), Serratia (%2.5), Providencia (%2.14) and Citrobacter (%1.79) which belonged to family Enterobacteriacea. Also the most important isolated genus of Vibrionacea were Vibrio (%47.55), Aeromonas (%28.67) & Plesiomonas (%4.9) and nonfermented-bacilli containg Suedomonace (%18.88). There was significant differences in the bacterial pollution between stations (P<0.05). The highest Coliform count was recorded during summer amounting to (147.71±171.36) ind. 100 cm3 and also the highest Fecal Coliform count was observed in summer (135.125±173.19) ind. 100 cm3 in the water. Generally the pollution in summer was higher in comparison to rest of the year due to increasing temperature and decreasing water flow of rivers.Higher bacterial pollution during autum in comparison to winter was attributed to heavay rain, erosion of the soil, flooding of the rivers and run off of the waste waters. Pirbazar river, Psikhan and Shambe Bazaar Roga drained high volume of urban agricultural and animal waste waters.The western area of the lagoon which is the bigest part of the Anzali lagoon had the least pollution.