BIOSORPTION OF Pb2+, Cd2+, & Ni2+ FROM WATERS BY ...

ecome evident. Nickel sensitive people can have asthma attacks, but not common
and some of them give a reaction consuming food or water containning nickel or
breathing dust containing it. Chronic bronchits and reduced lung function problems
are the consequences for the people who work in nickel refineries or nickel-
processing plants. Together with these problems, workers who drank water containing
higher concentration of nickel have stomach ache and suffered adverse effects to their
blood and kidneys (Agency for Toxic Substances and Disease Registry 2008). Nasal
cancer among workers in Ni refineries was reported in the 1930s, and conclusive
evidence of an increased risk of lung and nasal cancer in this group of people was
presented in the 1960s (Ebdon, et al. 2001). Nickel sulfide (Ni2S3) is considered to be
one of the most carcinogenic Ni compounds, as shown in experiments with animals
and in human lymphocytes (Ebdon, et al. 2001).
Nickel is an essential element for microorganisms and plants to carry out the
reactions which is vital response. By the way, the urease that is an nickel containig
enzyme assists in the hydrolysis of urea (Wikipedia 2008).
According to the EPA recommendations, drinking water should contain less
than 0.1 mg nickel/L (Environmental Protection Agency 2008).
1.3. Heavy Metal Pollution
Heavy metal pollution is a quickly growing problem for our oceans, lakes, and
rivers. It has started to influence our lives by its growing , so it can be emphasized
that it has to be awared of the problems due to heavy metals. It can be concluded that
the solution for the heavy metal pollution is demanding immediate actions. Since
heavy metals has an ability not to decay unlike organic pollutants, hence it is the
cause of challenge for remediation. It can be thought that the main cause of heavy
metal pollution is due to the industralization and its outcomes, and this brings to
threaten to human health, animals, plants, and the planet itself. Fertilizers and sewage
also are the another source of heavy metal pollutants, however, the pollution is
primarily based on the industralization.
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