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T. Sahoo et al.
established (Samet and Eradze 2000). On further research reported that nearly 70%
death due to lung cancer among mining people is because of exposure to radon, and
it was also reported that in comparison with other occupation non-smokers, miners
are in more risk zone of lung cancer (Samet 1989). Reports are there stating that
thirty per cent of people who neither smoke nor work in mining are affected by lung
cancer due to exposure to radon. The permissible level of exposure to this gas in many
countries is 200 Becquerel per metre cube, but there are reports showing results of
increase risk of lung cancer due to radon even at the level of 100 Becquerel per metre
cube (Mehra et al. 2006).
7.10.4 Fluoride
Among all the elements, fluorine is most reactive and electronegative and found in
the form of fluoride in nature (Deshmukh et al. 1995). According to Totsche and team
in the year 2000, fluoride washes into the water due to the weathering of fluoride
ion containing minerals (Totsche et al. 2000). Fluoride in small proportion is vital
for the strength of the enamel and providing minerals to bones as reported by Bell
and Ludwig in the year 1970 (Bell and Ludwig 1970). But, overexposure to this
fluoride leads to fluorosis of skeleton and teeth as reported by Sorg and Logsdon
in the year 1978 (Arif et al. 2012). According to Mameri and team in the year
1998, it was reported that the diseases of fluorosis have become common all over
the world apart from India especially in developing countries like New Zealand,
Thailand, Canada, Sri Lanka, Iraq, Kenya, South Africa, Turkey, Libya, Algeria,
USA, Japan, Argentina, etc. (Mameri et al. 1998). The major source for human
consumption of fluoride is groundwater. In groundwater, the prime sources of fluoride
are minerals containing fluoride like hydroxylapatite in rocks, cryolite, fluorapatite
and fluorspar as reported by Farooqi and team in the year 2007 (Prevedouros et al.
2004). Groundwater contamination by fluoride is a major issue as it carries major
health as well as environmental hazard in many areas.
7.10.5 Polycyclic Aromatic Hydrocarbon (PAH)
In the year 2004, Prevedouros and team reported that this substance is a part of the
group of compounds known as POPs, i.e. persistent organic pollutants, that generally exist as complicated mixtures consisting of two or more benzene rings, and the
resultant compound consists of only hydrogen and carbon (Prevedouros et al. 2004).
According to Harvey in the year 1997, there are around sixteen PAHs which are considered as priority pollutants capable of causing risk of cancer reported by United
States Environmental Protection Agency (Krupadam et al. 2010). These substances
are present in natural gas and oil, wood smoke, cigarette smoke, diesel engine, gasoline exhaust, etc., as reported by Li and Chen in the year 2002, Guteirrez-Dabanasnd
T. Sahoo et al.
established (Samet and Eradze 2000). On further research reported that nearly 70%
death due to lung cancer among mining people is because of exposure to radon, and
it was also reported that in comparison with other occupation non-smokers, miners
are in more risk zone of lung cancer (Samet 1989). Reports are there stating that
thirty per cent of people who neither smoke nor work in mining are affected by lung
cancer due to exposure to radon. The permissible level of exposure to this gas in many
countries is 200 Becquerel per metre cube, but there are reports showing results of
increase risk of lung cancer due to radon even at the level of 100 Becquerel per metre
cube (Mehra et al. 2006).
7.10.4 Fluoride
Among all the elements, fluorine is most reactive and electronegative and found in
the form of fluoride in nature (Deshmukh et al. 1995). According to Totsche and team
in the year 2000, fluoride washes into the water due to the weathering of fluoride
ion containing minerals (Totsche et al. 2000). Fluoride in small proportion is vital
for the strength of the enamel and providing minerals to bones as reported by Bell
and Ludwig in the year 1970 (Bell and Ludwig 1970). But, overexposure to this
fluoride leads to fluorosis of skeleton and teeth as reported by Sorg and Logsdon
in the year 1978 (Arif et al. 2012). According to Mameri and team in the year
1998, it was reported that the diseases of fluorosis have become common all over
the world apart from India especially in developing countries like New Zealand,
Thailand, Canada, Sri Lanka, Iraq, Kenya, South Africa, Turkey, Libya, Algeria,
USA, Japan, Argentina, etc. (Mameri et al. 1998). The major source for human
consumption of fluoride is groundwater. In groundwater, the prime sources of fluoride
are minerals containing fluoride like hydroxylapatite in rocks, cryolite, fluorapatite
and fluorspar as reported by Farooqi and team in the year 2007 (Prevedouros et al.
2004). Groundwater contamination by fluoride is a major issue as it carries major
health as well as environmental hazard in many areas.
7.10.5 Polycyclic Aromatic Hydrocarbon (PAH)
In the year 2004, Prevedouros and team reported that this substance is a part of the
group of compounds known as POPs, i.e. persistent organic pollutants, that generally exist as complicated mixtures consisting of two or more benzene rings, and the
resultant compound consists of only hydrogen and carbon (Prevedouros et al. 2004).
According to Harvey in the year 1997, there are around sixteen PAHs which are considered as priority pollutants capable of causing risk of cancer reported by United
States Environmental Protection Agency (Krupadam et al. 2010). These substances
are present in natural gas and oil, wood smoke, cigarette smoke, diesel engine, gasoline exhaust, etc., as reported by Li and Chen in the year 2002, Guteirrez-Dabanasnd