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Pesticides are compounds that used by human being, especially farmers for controlling biotical factors for a long time and can bring a lot of environmental problems. Among these compounds chlorine insecticide sprays have high half-life, the property of surviving for a long time and high lipophilicity characteristic. Due to having chronic consequences that resulted from consuming of this compounds, it is necessary to evaluation and analysis in environment especially in foods and also in fishes which have high fat and can carry this kind of insecticide sprays. So we have investigated the remaining of chloride organic insecticide sprays such as D.D.T, D.D.E in the four kinds of fishes in the Caspian Sea. In this investigation we have prepared for different kinds of fishes, which are highly used, available in the Caspian Sea (Sefid - koli- kilca - kefal) that we selected five fish from the four different hunting region (Chalous and Babolsar city and Khazar Abad and Miankaleh region ) in 2004. After cleaning, we prepared Hun muscle of the fished. Then, after the process of extraction, we distilled them in Vacuum by means of organic solvent and at last we evaluated the remaining and reported based on PPM by Gas Chromatography (GC) with ECD detector. The results of insecticides analyzed in four kinds of fishes been showed that the kafal kind of fish in the hunting region of Babolsar had the Highest amount of D.D.T at the rate of 0.031 PPM. Sefid in the hunting region of Babolsar was 0.03 PPM (P<0.05). It is necessary to mention that no research has so far been done to be a criterion for comparison in this area. But, fortunately the amounts of the insecticide sprays has not reached that offered level in fishes, and it raises the alarm.
Key words: D.D.T, D.D.E, Organochlorine residues, Caspian Sea, Fish
Synthetic organochlorines such as DDT and DDE are highly resistant to degradation by biological, photochemical or chemical means. They are also liable to bioaccumulation, are toxic and probably hazardous to human and/or environmental health. Most are prone to long-range transport these compounds are also typically characterized as having low water solubility and high li-pid solubility. The organ chlorines have been associated with significant environmental impact in a wide range of species and at virtually all tropic levels. Many organ chlorines have been implicated in a broad range of adverse human health and environmental effects, inÂcluding impaired reproduction, endocrine disruption, immunosuppression and cancer. ExÂposure to organ chlorines has been correlated with population decline in a number of marine mammals such as fishes.
The primary transport routes into marine and coastal environments include atmospheric deposition and surface run-off, the former being by far the greatest albeit dispersed over large areas. Because many organ chlorines are relatively volatile, their re-mobilization and long-distance redistribution through atmospheric pathways often complicates the identificaÂtion of specific sources.
The Caspian Sea, the largest inland sea in the world, is bordered by five countries: Iran, Azerbaijan, TurkmeniÂstan, Kazakhstan and Russia. It has no outlets and acts as a reservoir for water in the region. Environmental pollutants found in the sea probably arrive via the Mazandaran and Gilan rivers. Industrial complexes along the coast particularly in mazandaran and Gilan provinces, in Iran, also discharge waste directly into the Caspian Sea.
It is evident that seafood, particularly marine and freshwater fish, is a major component of the local diet; it is estimated that an average Iranian person especially in Mazandaran province consumes fish or shellfish three or more times per week.
The aim of this study was to survey levels of organochlorines (DDT and DDE) in the four species consumed fish availÂable from the local market in order to estimate potenÂtial human exposure.
Material and Methods
Four commonly consumed fish (Table 1) were purchased from a local fish market in February 2008 (n = 10).
Table 1. Four commonly consumed fish in thirds study
Clupeonell a delicatula
All samples were collected from Caspian Sea in July and August 2008. Five indiÂviduals of each fish were collected from four sites (Chalous and Babolsar city and Khazar Abad and Miankaleh region). Dorsal muscle of the samples were removed and frozen at -20 oC and shipped to central laboratory (Sari city) for analysis. Concentrations of DDT and DDE were determined.
Sample preparation and analysis
The sample preparation and analysis protocols are similar to those described in Vida and Anuschka, 1998. Briefly, approximately 5 g of dorsal muscle from Samples fish was thawed and homogenized with 60 g of anhydrous sodium soleplate in a mortar until a free-flowing powder was obtained. The sample was extracted with 225 ml of 1, 1 methylene chloride/hexane. Extracted sample was injected to Gas chromatography in electron capture detector (ECD). OC levels (DDT and DDE) were measured using the internal standard method in conjunction with the corresponding external standards using selected ion monitoring mode.
Results and Discussion:
Concentration of DDT and DDE contents in the four species of fishes in Caspian Sea are presented in Table 2 and shown in Figures 1 and 2. DDT and DDE measured in all Samples that Hunted from four fishery Regions.
According to Table2, DDT Residues Regarding Sefid fish has maximum amounts (0.027 PPM) in Babolsar. In Chalus and Babolsar Regions , Regarding Koli fish , the amounts of DDT Content Were the Greatest and Close together (0.022 in Chalus and 0.023 in Babolsar). The Samples of Kafal fish in Chalus Presented the maximums of DDT Content (0.031 PPM) and Finally the Kilka fish in Comparison to other fishes, Presented the minimum of DDT Content in above fishery Regions.
Residues of DDE in the above Species of fish Were found in the Order of Sefid (Babolsar , 0.030) > Kafal (Chalus, 0.029) > Koli (Chalus, 0.025) During the Analysis Whereas regarding Kilka fish, Presented the minimum of DDE Contents in Compared to Other fishes Under Study.
Statistical Analysis (One-way ANOVA), indicated that there isn't Significant difference regarding DDT contents (P<0.05, sig =0.016) but Significant difference regarding DDE (P<0.05, sig =0.040) among Fishery Sites.
The results presented that difficulty of poisonous residues is very serious and important and Since researches in the case of Caspian sea fishes is very little, to compare with this study, then, there is a requirement to complete survey in Caspian sea (Mazandaran province) and Southern Coasts of Caspian sea.
Other study in north Atlantic indicated that means of DDT (0.002 PPM), DDE(0.002 PPM), Dieldrin (0.006 PPM) and Endosulphan (0.007 PPM) in liver samples (in Shir bit fish), that these levels were lower than quantities proposed by WHO (0.05 PPM) .
Quantities of DDT and DDE in Caspian sea (Table 2.) was lower than WHO Standard levels (0.05ppm) but in comparison to all regions and other poisons, presented higher quantities for great use by farmers in Northern province in Iran (southern coasts of Caspian sea) and great distribution by agriculture center in Mazandaran among farmers there is evidence that the population of seals in the Caspian sea is declining and fertility rates are decreasÂing. Further studies on contaminants in live animals and biomarker responses that may indicate reproductive interference are needed before we can conclude that the "high levels of DDT insecticides in this population are toxicologically important".
Table 2. The average quantities of DDT and DDE contents (PPM) in four species of fishes
in Caspian sea
Kind of fish
Mean of DDT (PPM)
Mean of DDE (PPM)
Measurement of poison residues in food products (agricultural, sea, etc) should be regularly performed according to per capita consumption of poisons.
Establishment of reference laboratory, which was equipped with analytical apparatus such as GC, GC-Mass, HPLC, etc in the districts unavoidable.
Health care organization such as fishiness agriculture, rice, environmental and the ministry of health investigation centers have to precisely identify environmental pollution's and determine better strategies to achieving wholesome foods.
Establishing the poison and environmental pollution information center to guide the people all the time and inform them about the control of toxicity can be helpful.
Educating the province's farmers about the better using of poisons especially chlorinated poisons that their using has been abolished, is necessary.
Replacing new methods in combat against vegetable pest such a biological pesticides (e.g. trichograma beans against phyllophagou worm) and bacterial pesticide (e.g. Bacillus).
Chlorinated poison residues in husbandry products such as dairy products should be determined.
Measuring chlorinated poison residues in sea products, because the contaminated water eventually reach to sea.
Measuring chlorinated poison residues in human (Milk, fatty tissue, blood, liver, etc) should be done.