International Journal of Science and Research (IJSR) ISSN (Online): 2319-7064 Index Copernicus Value (2015): 78.96 | Impact Factor (2015): 6.391 Volume 6 Issue 1, January 2017 www.ijsr.net Licensed Under Creative Commons Attribution CC BY Toxicity of Heavy Metals and their Effects on Freshwater Fish Cyprinus Carpio in River Bhavani P. Ranganayaki 1 , Dr. Y. Thangam 2 , Dr. M. Rabeeth 3 Chinna Arts and Science College, Department of Zoology, Tiruppur Dt, Tamilnadu, India PG and research department of Zoology, J.K.K.Nataraja College of Arts and Science, Kumarapalayam, Mamakkal Dt, Tamilnadu, India Abstract: The environment is everything that surrounds us and gives us life and health. The aim of the study is to determine the accumulation of heavy metals in fish Cyprinus carpio in river Bhavani. The accumulation of metals in water were observed and bioaccumulations of heavy metals like Cd, Cr, Cu, Fe, Pb, Zn, Mg, in fresh water fish were evaluated. The evaluations were calculated in percentage. Toxic pollution arrives from heavy metals, such as cadmium, chromium, copper, iron, lead, zinc, magnesium. These metals pollute the surface water and ground water. It affects the fish and human beings. The accumulation of metals in tissues like gill, liver, intestine, kidney and muscle were observed and evaluated. The changes in river and fish were noted. Keywords: Cyprinus carpio, Bhavani river, metals- Cd, Cr, Cu, Fe, Pb, Zn, Mg, Accumulation, Bioaccumulation. 1. Introduction Over two thirds of Earth's surface is covered by water, less than a third is taken up by land. As Earth's population continues to grow, people are disposing ever-increasing pressure on the planet's water resources. Pollution is a human problem because it is a relatively recent development in the planet's history. Before the 19th century Industrial Revolution, people lived more in harmony with their immediate environment. As industrialization has spread around the globe, the problem of pollution has spread with it. When Earth's population was much smaller, no one believed pollution would ever present a serious problem. It was once popularly believed that the oceans were far too big to pollute. Today, with around 7 billion people on the planet, it has become apparent that there are limits. Pollution is one of the signs that humans have exceeded those limits. Pollution from toxic chemicals threatens life on this planet. Every ocean and every continent, from the tropics to the once-pristine polar regions, is contaminated." Water pollution can be defined in many ways. Usually, it means one or more substances have built up in water to such an extent that they cause problems for animals or people. Oceans, lakes, rivers, and other inland waters can naturally clean up a certain amount of pollution by dispersing it harmlessly. The chemicals, metals, fertilizers have an effect on the quality of the water. This, in turn, could affect the health of all the plants, animals, and humans whose lives depend on the river. (Chris Woodford, 2016). Water pollution depends on the quantities, how much of a polluting substance is released and how big a volume of water it is released into. A small quantity of a toxic chemical may have little impact if it is spilled into the ocean from a ship. But the same amount of the same chemical can have a much bigger impact pumped into a lake or river, where there is less clean water to disperse it. Water pollution almost always means that some damage has been done to an ocean, river, lake, or other water source. A 1969 United Nations report defined pollution as: When we think of Earth's water resources, we think of huge oceans, lakes, and rivers. Water resources like these are called surface waters. The most obvious type of water pollution affects surface waters. A spill from an oil tanker creates an oil slick that can affect a vast area of the ocean. Not all of Earth's water sits on its surface, however a great deal of water is held in underground rock structures known as aquifers, which we cannot see and seldom think about. Water stored underground in aquifers is known as groundwater. Aquifers feed our rivers and supply much of our drinking water. They too can become polluted, for example, when weed killers used in people's gardens drain into the ground. Groundwater pollution is much less obvious than surface-water pollution, but is no less of a problem. In 1996, a study in Iowa in the United States found that over half the state's groundwater wells were contaminated with weed killers (Dana Koplin, 1997). Surface waters and groundwater are the two types of water resources that are affected by pollution. There are also two different ways in which pollution can occur. If pollution comes from a single location, such as a discharge pipe attached to a factory, it is known as point-source pollution. Other examples of point source pollution include an oil spill from a tanker, a discharge from a smoke stack (factory chimney), or pouring oil from car down a drain. A great deal of water pollution happens not from one single source but from many different scattered sources. This is called nonpoint-source pollution. Most water pollution doesn't begin in the water itself. Take the oceans: around 80 percent of ocean pollution enters our seas from the land. Virtually any human activity can have an effect on the quality of our water environment. When farmers fertilize the fields, the chemicals they use are gradually washed by rain into the groundwater or surface waters nearby. Sometimes the causes of water pollution are quite surprising. Chemicals released by smokestacks (chimneys) can enter the atmosphere and then fall back to earth as rain, entering seas, rivers, and lakes and causing water pollution. That's called atmospheric deposition. Water pollution has many different causes and this is one of the reasons why it is such a difficult problem to solve. Paper ID: 4011702 1218