Effect of Different Heavy Metal Pollution on Fish

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Effect of Different Heavy Metal Pollution on Fish ARTICLE · FEBRUARY 2014

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Research Journal of Chemical and Environmental Sciences Res. J. Chem. Env. Sci., Volume 2 Issue 1 February 2014: 74-79 Online ISSN 2321-1040 CODEN: RJCEA2 [CAS, USA] Available Online http://www.aelsindia.com ©2013 AELS, India

RESEARCH ARTICLE

Effect of Different Heavy Metal Pollution on Fish Sehar Afshan, Shafaqat Ali*, Uzma Shaista Ameen, Mujahid Farid, Saima Aslam Bharwana, Fakhir Hannan, Rehan Ahmad Department of Environmental Sciences, Government College University, Allama Iqbal Road, 38000, Faisalabad Pakistan. *Corresponding author: e-mail: [email protected] ABSTRACT The purpose of thisreview was to check the accumulation and concentration of heavy metals in different organs of fresh water fishes that comes in contact with the water contaminated with the heavy metals. The subjected fish were exposed to cadmium (Cd), zinc (Zn), chromium (Cr) and lead (Pb) at sub lethal levels. Heavy metals entered in bodies of fishes by three potential ways: by gills, by body surface and digestive track. The estimated accumulation of heavy metals in the liver and gills were in order of Pb > Cd > Ni > Cr and Cd > Pb > Ni > Cr. correspondingly, the order in case of kidneys and flesh tissues was and Pb > Cd > Cr > Ni and Pb > Cr > Cd > Ni. In Cyprinus carpio(Common carp) the concentrations of cadmium and lead was deliberately raised in tissues as compared to the other heavy metals. Heavy metals accumulate in fresh water and elevate through food chain and fishes are badly affected because they are top consumer in aquatic systems. Humans are also affected by intake of fishes for mostly people of those areas where main food is fish. Keywords – accumulation, bio-magnification , digestive track, gills, pollution, Received 27/12/2013 Accepted 29/01/2013

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INTRODUCTION The universal problem is the environmental pollution and most important pollutants are the heavy metals in aquatic network because of their toxicity, accumulation and bio-magnification by marine creatures. Domestic, industrial and anthropogenic activities may broadly become the source of natural aquatic systems contamination of heavy metals [1,2]. The pollution caused by heavy metals might have. The heavy metal pollution have dreadful effects on the environmental equilibrium and a variety of aquatic entities [3,4]. In the list of animal species, detrimental effects of these pollutants, can never be negligible for fishes [5,6,7]. Fishing is a also general pastime [8,9,10] including in urban areas [11].The pollutants such as heavy metals bioaccumulate in food chain and cause the antagonistic effects, even death so fish among other animals are used to determine the health condition of aquatic ecosystem [12,13]. Accumulation patterns are more in some fish species than others because of the ability of fish to bioaccumulate metals [14]. Heavy metals in fish come mainly from their diet, and levels of bioaccumulation of contaminants are higher in fish which comes higher in food chain [15]. In this study, the levels of five heavy metals i.e. zinc, nickel, cadmium, lead and chromium has been determined from the fishes, sediments and water. Heavy metals concentrate in water and entered into the food chain. The patterns of bioaccumulation of heavy metals are determined by the absorbance and excretion rates of fish. Different factors such as physical and chemical properties of water as well as seasonal changes are the reason of significant augmentation of metals in different fish tissues [16, 17]. Metal residual problems in the fish epithelium are stern, because of the presence of higher metal concentrations in water and sediments [18]. On the contrary, heavy metals are of serious concern in this respect because they can be easily elevated in the food chain due to their bioaccumulation processes [19]. The pattern of heavy metal uptake in fish is different in different species according to various factors i.e. the developmental and psychological factors and also the age of the fish. Fish can transport major dietary sources of arsenic and mercury to humans because of their higher uptake mechanism in their tissues towards these elements. Processed water from the, detergent, textile and cosmetic industries present near the river water have high concentrations of heavy metals, which cause the disruption of the ecological balance of river water if present in much higher concentrations. The scheme of accumulation regarding heavy metals in the liver and gills was found maximum forCd and Pb respectively. Similarly, forflesh tissues the maximum

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concentration of Pb and Cd was found. In all heavy metals, the bioaccumulation of lead and cadmium proportions was extensively augmented in tissues of Cyprinus carpio (Common carp). EFFECTS OF HEAVY METALS ON FISHES The toxic effects of heavy metals can affect the individual growth rates, physiological functions, mortality and reproduction in fish [20]Heavy metals entre in fish bodies by three possible ways: by gills, by digestive track and body surface. The gills are considered as the significant site for direct uptake of metals from the water [17, 19], though the body surface is normally estimated to take minor part in uptake of heavy metals in fish [21]. Heavy metal accumulation can also be caused by the food source, possibly leading to bio-magnification, the augmentation of toxins up the food chain [22]. The periodic difference of heavy metals based on the data of two consecutive years and samples gathered from the fish farmexposed the following result: summer > autumn >winter > spring. As a human food, Fish are considered as an excellent source of polyunsaturated fatty acids (predominantly omega-3 fatty acids), protein, Zn, iron and calcium [8]. Seafood will be an even more important and safe source of food in future for protein and fatty acids for human intake and products made from aquaculture (WHO, 1999). Different factors that are considered to be critical are size, developmentalstage and salinity in heavy metal toxicityto marine and estuarine organisms [23].Affected organisms show response to heavy metals by accumulating in theirbodies or by shifting to the next trophic level of the food chain [24]. Effects of chromium on fish Heavy metals accumulated in fish either from the surrounding water or by ingestion of food in environment [25]Due to anthropogenic activities natural water is being contaminated by this metal. The chromium concentration in rivers and lakes stated to range between 1 to 10 ug/L and EPA recommendation for permissible level are 50 to 100 ug Cr/L for protection of human health and aquatic life respectively.Some species of fishes have poisonous effect of chromium as echoed in the blood changes such as anemia, eosinophilia and lymphocytosis, bronchial and renal lesions.Chromium known for its lesser accumulation in fish bodies while the higher concentrations of Cr damages the gills of fish swimming near point of Cr disposal[26]. Effect of chromium on humans by fish intake Fish being at the higher level of the food chain accumulate large quantities of metals and the accumulation depends upon the intake and elimination from the body [27]. Cr (VI) is harmful to human health, mainly for those who work in textile and steel industry. The tobacco smokers also have higher possibility of disclosure to Cr. Chromium (VI) can cause many health effects. Chromium in leather products can cause skin rash like allergic reactions. After breathing in Cr can cause noseirritations andnosebleeds[27]. Other health problems caused by Cr (VI) are:  Faded immune system  Skin diseases  Cause ulcer and upset stomach  Respiratory track problem  Alteration in genetic material  Lung cancer  liver and kidney damage  Death Effects of cadmium on fish Cadmium is the non-essential andmost toxic heavy metal which is widely distributed in the aquatic environment and earth's crust. In the list of heavy metals such as lead, mercury and cadmium are considered to cause public health hazards [28]. Burning of fossil fuels and municipal waste are known to be largest sources of cadmium release to the environment (such as coal or oil) [29]. Cadmium may also enter into the atmosphere from zinc, lead or copper smelter [30]. It can enter into the fresh water by disposal of industrial and household waste. Fertilizers often contain some cadmium. Reproduction rate of aquatic organisms may also be affected due to Exposure to heavy metals and can lead to a gradual extinction of their generations in polluted waters [31].For example, Cd and mercury (Hg) damage the kidney and produced signs of chronic toxicity, including impaired reproductive capacity and kidney function,tumors, hypertension and hepatic dysfunction [32]. Fish creates major sources of human beings food which is protein.Fishes are major part of the human diet and it is therefore not surprising that numerous studies have been carried out on metal pollution in different species of edible fish [33, 34, 35]. The nutritiveneed of different tissues of fish depends on their biochemical configuration like mineral contents, amino acids, protein and vitamins,etc. The sub lethal concentration of Cd has showed deviations on the electrophoretic arrangements of protein segments in gills and muscle O. mossambicus.


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Health effects of cadmium in humans by intake of fish Unfortunately the chemical contaminants are stored within the lipid component of the fish[36]so they are well protected when entering the human body. Wild fish from certain polluted areas may be highly contaminated.[37] Metals such as cadmium, mercury, arsenic and lead are non-essential and therefore have toxic effects on living organisms [38, 39, 40]. These heavy metals accumulate in tissues and body of aquatic organisms in higher concentration than concentrations in water and biomagnified in food chain that cause physiological damages at higher trophic levels and in human consumers. Human beingtakes Cd mainly through food. Foodmaterialscontains higher Cd can significantly increase the Cd concentration in human bodies. The food materials that contain higher Cd are;fish liver, shellfish,mushrooms, dried seaweed etc. In start Cdtransported to liver through the blood where it bond to proteins to form complexes that are transported to kidneys where it harms the purifying mechanisms. In results, this causes the excretion of sugars and essential proteins from the body and further damage kidneys. It takes time before Cd that accumulated in kidneys and excreted from human body. Other related health effects caused by cadmium are:  Diarrhea  Vomiting  Stomach problems  Fractures in bone  Damage to DNA  Failure in reproduction and fertility  Cause damage to nervous system  Damage to immune system  Cause cancer Effects of Zinc on Fish Zinc can accumulate in the bodies of fish, when they live in Zn contaminated water courses. When zinc enters into the bodies of these fishes, it results inbio magnify up the food chain. The Zn concentrations in fish tissue decreased meaningfully with increasing length of the fish, is regarded as a controversial subject [8],Zinc, an essential element, is one of the most common heavy metal pollutants. The sources of zinc and other heavy metals in natural waters may be from geological rock weathering or from human activities such as industrial and domestic wastes water discharges and animals where it forms constituent functions in maintaining cytoplasmic veracity [14]. However at higher concentrations, Znproduced adverse effects in fish by structural damages, which affects the growth, improvement and survival of fish. Zinc accumulates in the gills of fish and this designates a depressing effect on tissue respiration leading tohypoxia which results in death. Zinc pollution also tempts changes in ventilator and heart physiology[5]. Sub-lethal levels of zinc have been known to unfavorably affect hatchability, existence and hematological strictures of fish. Zinc could cause sub-acute effects that change fish behaviors. Such observed behaviors include deficiency of balance since most fins are stationary in the affected fish, restless swimming, air guzzling, periods of dormancy and death. [42]The Zn danger is taken as very serious because of itsalmost unlimited persistence in the environment because it just transformed from one oxidation state or organic complex to another and cannot be destroyed biologically. Zinc is a potential toxicant to fish [4] which causes disturbances of acid-base and ion regulation, disruption of gill tissue and hypoxia [43]. Effects of Zinc on Humans by Intake of Fish Its need of time to define the concentrations of heavy metals in commercial fish and shrimps in order to determine the possible risk of human consumption. Accumulation of heavy metals in tissues mainly depends upon concentration of metals in water and exposure period; although some other environmental factors such as salinity, pH, hardness and temperature play significant roles in metal accumulation [44]. Zinc isunique element that is little essential for human health. When people exposed to little Zn they can experiencedecrease in sense of taste and smell,loss of appetite, slow wound healing and skin sores while Zn deficiencies can even cause birth defects. Although humans’beings can manage large concentrations of Zn, too much Zn can cause prominent health problems such as skin annoyances, such as stomach cramps, anemia, vomiting and nausea. High levels of Zn damages the pancreas and disturb the protein metabolism, and cause arteriosclerosis. Extensive exposure to Zn chloride can cause respiratory disorders. However, it is worth mentioning that some of the researchers are of the view that adverse effects of the fish are neutralized in the process of cooking. Moreover, such negative effects are further reduced while p7r4àcking the fish for human feasting. Effects of Lead in Fish When accumulation reaches a substantially high level, accumulated heavy metals in the tissues of aquatic animals and may become toxic [45]. Aquatic organisms exposed to a higher concentration of heavy metals


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in water may take up substantial quantities of these metals. Bio-magnification of a pollutant may lead to toxic levels in species high up in the trophic chain and in freshwater systems. Lead (Pb) is as a potent environmental pollutant. Lead toxicity has become very important due to its great concern for human health [46, 47, 48]. Fish are usually among the top consumers. [41]. Fish and people are primarily exposed to Pb by food ingestion and breathing. Lead accumulates in the muscles, bones, blood and fat. Newborns and young children are especially delicate to even low levels of lead. [49]  Effects organs - Pbseverely damage to liver, kidneys, brain, nerves and other organs. Exposure to Pb may also lead to reproductive disorders osteoporosis (brittle bone disease) and  Affects the blood and heart - Pb exposure causes increases in heart disease, high blood pressure, especially in men. Pb also causes anemia.  Affects the nerves and brain - Extensive exposure to Pb causes memory problems appropriations, behavioral disorders, mental retardation while lesser levels of Pb damage the nerves and brain in fetuses and young children, resulting inlowered IQ and learning deficits.  Effects on Fish - Lead enters in water systems through runoff, industrial and sewage waste streams. Increasing levels of Pb in the water can cause generative damage in some aquatic life and cause blood and nervous changes in animals and fish and other [50, 51,52] CONCLUSION Heavy metals likecadmium (Cd), nickel (Ni), chromium (Cr)and lead (Pb) were tested in different organs like gills, livers, kidneys and flesh tissues of the control fish enduring in natural water system. And most of the metals are present in edible portion of fish. Humans are also affected by eating fish and can cause a few of health problems.The levels of toxic elements in different fishes depend on the fish sex,age, season and place. The pollution of waterways with anthropogenic activities are the major cause of aquatic loss and imbalanced food chain. To eliminate and avoided the aquatic life loss there is need to use the advanced technologies generating less heavy metal pollution to environment. REFERENCE 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17.

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CITATION OF THIS PAPER Sehar Afshan, Shafaqat Ali, Uzma Shaista Ameen, Mujahid Farid, Saima Aslam Bharwana, Fakhir Hannan, Rehan Ahmad. Effect of Different Heavy Metal Pollution on Fish. Res. J. Chem. Env. Sci., Volume 2 [1] 2014: 74-79


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