The present study indicates the toxic effects of Copper Sulphate on fish. The sublethal toxicity of Copper Sulphate on protein content in liver, kidney and muscle of fish Mystus vittatus have been studied. The fish exposed to sublethal concentration of 1/20th (low), and 1/10th (high) for the period of 10, 20 and 30 days. The results showed decrease in the protein content and increase in the amino acid content in liver, kidney and muscle of fish Mystus vittatus. The significant reduction in protein content and elevated levels of amino acids is apparently indicative of the toxic effect of Copper Sulphate on biochemical parameter and organism’s response to the toxic stress.

Freshwater systems are exposed to a variety of pollution sources, such as industrial waste, domestic sewage, agricultural disposal and mining processes. Most of the heavy metals entering into the food chain cause physiological damage for aquatic organisms. The toxicological effects of heavy metals are to non-target organisms like freshwater fishes. Lead is the most important heavy metal that causes bio accumulative toxicity in fish and other aquatic organisms. Lead nitrate is one of the heavy metals, that are found in the environment and causes many adverse effects. Oreochromis niloticus is an important species in commercial fisheries in the world. Human consumption of heavy- metal polluted water can have direct or indirect effects on human health. The present study analyzed the accumulation of heavy metals in water, fish Nile tilapia and also conducted a health risk assessment on humans. In the present study, the 96h LC50 values recorded for lead nitrate was 43ppm.The fish Oreochromis niloticus were treated for the sub lethal concentration of 1/10th,1/20/ and 1/30of lead nitrate (Pb (NO3)2) for the period of 30 days to get biochemical variations of different tissues in the Gill, Liver, Muscle and Kidney. The decreased level of Carbohydrate observed in Lead nitrate exposed fish at all the sub lethal concentrations (1/10, 1/20 and 1/30). The level of total protein and Lipid concentrations were decreased in Gill, Liver, Muscle and Kidney of lead nitrate treated fish Oreochromis niloticus. The depletion of protein, lipid, Carbohydrate content in Gill, Liver, Muscle and Kidney tissues of Oreochromis niloticus was due to the toxicant stress caused by Heavy metal Lead nitrate. A questionnaire-based dietary survey was conducted in 1000 healthy humans from the general population at various fish markets in various places of Krishnagiri district, Tamilnadu. Dietary data were collected in detail through face-to-face interview only on tilapia consumption. Intake (g) was computed. Statistical analyses were conducted using SPSS for Windows and all tests were considered significant at p< 0:05

Heavy metals pollution is a great environmental problem in recent years throughout the world. Various activities such as domestic, anthropogenic activities, volcanic eruptions and industrial activities which increase their level of heavy metals concentration into the environment. Copper sulfate is used as an algaecide and fungicide in the fields of agriculture and aquaculture being discharged into water bodies and it can affect the aquatic organisms, especially fishes. The present study deals with the effect of copper sulfate on various hematological parameters of the experimental fish Oreochromis niloticus. Oreochromis niloticus is an important freshwater fish in commercial aquaculture. Fish is a significant food component of human food. Fish are the suitable bio-indicators of heavy metal contamination. Heavy metals are oxidative stress inducers in fish and can reflect aquatic contamination. The Objective of the present study was to analyze the hematological effects of heavy metal CuSO4 on the freshwater fish O.niloticus. The LC50 value of copper sulfate found to be 39.2 mg/L. The fish Oreochromis niloticus were experimented for the different sub lethal concentrations of 1/10, 1/20 and 1/30 of copper sulfate for the period of 30 days to get hematological changes. At the end of the experiment the result shows that the Red Blood Cell (RBC) count and the percentage of hemoglobin (Hb) were significantly decreased as the sub-lethal concentration of heavy metal Copper sulfate increased, while the level of WBC, MCV and MCH significantly increased. The effect of copper sulfate was observed by histopathological investigation of gill and liver of treated fish. The aim of present study is to investigate the hematological and histopathological effects of copper sulfate for the period of 30 days at various sublethal concentration in various tissues of the freshwater fish O. niloticus.Dietary data were collected in detail through face-to-face interview on tilapia O.niloticus consumption. Intake of fish (g) was computed. Statistical analyses were conducted using SPSS software for Windows and all tests were considered significant at p<0:05.

Pollution is now a day has become a threat to living beings. Pollutants in the form of pesticide inhabit a variety of environments which affect the normal vital activities of organisms living. They reach the aquatic environment as a washout from agriculture fields as well as from industrial areas. Pesticide contamination in water may accumulate in the bodies of animals and affect the vital organs which alter the usual activities. Cypermethrin is a synthetic pyrethrum insecticide used in agriculture to control pest in crops such as lettuce and cotton and household pest such as cockroach. To understand the toxic effect of pesticides, it creates a need for histopathological observation of tissues. Present work was carried to evaluate the toxic effect of cypermethrin (25% EC) in liver and gills of tilapia (O.mossambicus). The fish experimented to different sublethal concentration of 1/10th,1/20th and 1/30th level of LC50 (4.5 mg/l) value of cypermethrin for 30 days. Gill exhibited epithelial cell damage, Fusion , Length reduction , Curling and Repturing of secondary gill lamellae, primary gill lamellae Enlargement, Necrosis, Cytoplasmic vacuolization, Damaged red blood corpuscle, Excessive secretion of mucus, whereas liver showed increased vacuolization, Necrosis, Hyperplasia, disintegration of hepatocytes and necrotic nuclei. Aim of the present study is to identify the effect of cypermethrin on organs tissues ( liver, kidney) of   freshwater fish, Oreochromis mossambicus. Keywords: Cypermethrin, Oreochromis mossambicus, Gill, Liver

The toxic effect of Monocrotophos on some biochemical parameters such as Protein and Amino acid in freshwater fish Oreochromis mossambicus were studied. The fishes exposed to 1/10th, 1/20th, and 1/30th sublethal concentration of Monocrotophos for 30 days. The tissue samples of gill, liver were analysed at the end of the 30th day exposure period. A decreased value of Protein and Amino acid were observed in 1/10th, 1/20th, and 1/30th sub lethal concentration of Monocrotophos at the exposure period of 30 days while comparing with the control group. The high variation observed in the 1/10th sublethal level of 30thday exposure. While compare with control group the effects of Monocrotophos on fish found during this experiment showed that the level of protein and amino acid level in various tissues (gill and liver) of Oreochromis mossambicus decreased.