Shells of Bufonaria echinata as biomonitoring materials of heavy metals (Cd, Ni and Pb) pollution in the Persian Gulf: with emphasis on the annual growth sections

Concentrations of heavy metals (Cd, Ni and Pb) were determined in soft and hard tissues (three separated shell sections) of gastropod Bufonaria echinata as well as surficial sediments collected in October 2015 from two sampling sites located in the sub-littoral zone of Qeshm Island, Persian Gulf. There were significant differences between the sampling sites for concentrations of all the three elements in the shells and sediments. But in terms of the soft tissues, in the case of Ni and Pb significant differences between the sites could be observed. In all the cases, higher levels were observed in the samples from Suza site, which may be mainly due to the proximity of this site to the relevant anthropogenic sources. Comparison of the gained data from this study with the other relevant researches shows that in most cases the levels of the elements in the soft tissues and shells either fell within the range for other world areas or were lower. The observed increasing trends of metals accumulation in the shell sections (from older to younger sections) could be mainly attributed to the gradual increase of relevant anthropogenic pollutants in the study area, especially in Suza pier, during the recent years. Generally, it can be concluded that the shells of B.echinata could be possibly employed as a biomonitoring tool for historic metals contamination in northeastern part of the Persian Gulf

The study of pollution in the Gorgan bay

From an environmental standpoint bays around the world are very important ecosystems including the Gulf of Gorgan Bay and thus are important. Which has a relatively low depth, a little flow, temperature appropriate, biogenic materials and abundant food in the sea suitable for children sometimes place (Nursery ground) and also the perfect place for power (Fattening ground) is an early sea fish. In this research effort will be the initial studies on the impact of environmental pollutants on the ecosystem of the Gulf of Gorgan and the quality and quantity of pollution, especially pollution, agricultural pesticides and entering the Gulf of Gorgan and the impact on the ecosystem's the initial assessment and the monitoring of changes in them over the years. The user in the Gulf of Gorgan, agriculture. Pollution from agricultural fields related to pesticides and fertilizers are used in the fields. According to consumer research, and the remaining amount of pesticides in water and sediments of the Gulf of measured, indicated that most of the remains of chlorinated pesticides in sediments of the pesticides used in the agricultural sector In addition, all the toxins in the summer and spring peak. In addition, the DDE concentration compared to other poisons. In the case of other contaminants in the area is now threatened by the Gulf of Gorgan, although not serious, but it seems that the increase in organic matter and reduce the amount of oxygen of the water. The near future to Eutrofication risks in the ecosystem