Some heavy metals are essentials for the metabolism of our body. But too high concentration of the metals can lead to poisoning on the body system too. When talked about the danger of heavy metals, we are talking about the bioaccumulation that heavy metals can do to human tissues. Ojovan and Lee (2005) said that lack of care when dealing with heavy metals could demonstrate the seriousness of high level exposure Bioaccumulation happens when there is an increase in the chemical concentration in an organism. Toxic metals compounds will accumulate in the body any time they are taken up and were stored faster than they are metabolized or excreted.
Other source can include unsafe or excess application of pesticides, fungicides and fertilisers (Zhen-Guo et al., 2002). Additional potential sources of heavy metals include irrigation water contaminated by sewage and industrial effluent leading to contaminated soils and vegetables (Bridge
Natural aquatic bodies are being polluted due to untreated effluents released from agricultural, industrial and sewage waste waters. These pollutants are harmfully affecting the aquatic life, including fish (Gagnaire et al., 2004). Among aquatic pollutants, there exist organic and inorganic compounds such as combustible substances, petroleum products, phenol, textile dyes and heavy metals. Among inorganic contaminants, heavy metals are the prominent ones (Jadhavet al., 2010). Fish are more susceptible to the harmful impacts of pollutants and serve as an excellent tool for understanding the health status of aquatic ecosystem (Donohue et al., 2006).
Pollution is the cause of many health risks to both humans and animals and is continuing to spread. Each type of pollution comes in various forms and has many effects, all of which can cause harm to the environment and the people who live in it. As long as humans are on Earth there will be pollution, but the actions one makes every day have the ability to drastically reduce the
Some of these food crops are sold in the markets or consumed in the home. There is increased awareness that heavy metals present in soil and food may have negative implications on human health and on the environment (Abraham, 2002; Selinus et al., 2005). From the environmental point of view, all heavy metals are largely immobile in the soil system, so they tend to accumulate and persist in agricultural soils for a long time. The most frequently reported heavy metals with potential hazards in soils are Copper, Cadmium, Chromium, Lead and zinc (Alloway, 1995). The concentration of these toxic elements in soils may increase from various sources
Heavy metals had taken a great attention in scientific studies throughout the past years. In this generation, the amount of toxic materials found in land and water as well as in air has increased drastically. Constant development on modern technology depends on usage of heavy metals. Incorporated with this, heavy metals have major disadvantages of being toxic and having a long half-life. ( Godt, Scheidig, and Grosse-Siestrup et al, 2006; Gunduz and Akman, 2012; WHO, 1995; WHO, 2004) Cadmium, chromium and lead, among other heavy metals are known to be dangerous pollutants in our environment.
The environmental pollution has been a major area of concern worldwide. The increasing of concentration of toxicants like heavy metals in the environment is due to the industrial and agricultural process. As a result the amount of concentration of toxicants being taken up by plants or animals into their system and cause further distribution to the environment. For examples in the case of cow’s milk in liquid or powder form that is being consumed by humans, it will affect the human health due to the contamination of toxicant in the product. Milk can be contaminated with heavy metals through exposure of lactating cow to pollution or consumption of feeding stuffs and water with toxicants.
However, due to natural causes but mainly pollution, the concentration of the trace elements (also considered to be heavy metals) in the soil has been increased thereby leading to heavy metal pollution. The heavy metal pollution not only affect the soil and plants, but also human
The pollution of aquatic environment with heavy metals constitutes a public health hazard during recent years. Untreated municipal and industrial wastes, together with inputs from the atmosphere, are the primary sources of heavy metal pollution of fish. Moreover, fresh water fishes are more sensitive to heavy metals than marine species specially lead (Pb), cadmium (Cd) and mercury (Hg) which are among the most dangerous heavy metals (Sorensen, 1991). Methyl mercury poisoning may be occurred among populations where fish were the major dietary stable. The signs and symptoms of chronic methyl mercury poisoning depend on the amount and duration of exposure, the age of the patient and individual sensitivity.
Heavy metals concentrations in aquatic ecosystems are usually monitored by measuring their concentrations in water, sediments, and biota (Oguzie, 2003). Pollution by heavy metals is a serious problem due to their toxicity and ability to accumulate in the biota (Islam and Tanaka, 2004). Metal pollution has a harmful effect on biological systems and does not undergo biodegradation and accumulated in living organisms, thus causing various diseases and disorders even in relatively lower concentrations (Pehlivan et al., 2009). A substantial level of heavy metals causes the major hazard to the environment and accumulates in the ecosystem through two major paths; the first path