A case study of pesticide pollution in India
One of the most terrifying effects of pesticide
contamination of ground water came to light
when pesticide residues were found in bottled
water. Between July and December 2002, the
Pollution Monitoring Laboratory of the New
Delhi based Center for Science and Environment
(CSE) analysed 17 brands of bottled water both
packaged drinking water and packaged natural
mineral water commonly sold in areas that fall
within the national capital region of Delhi. Pesticide
residues of organochlorine and organophosphorus
pesticides which are most
commonly used in India were found in all the
samples. Among organochlorines, gammahexachlorocyclohexane
(lindane) and DDT were
Chapter5.p65 153 4/9/2004, 5:09 PM
154 Environmental Studies for Undergraduate Courses
prevalent while among organophosphorus pesticides,
Malathion and Chlorpyrifos were most
common. All these were present above permissible
limits specified by the European Economic
Community, which is the norm, used all over
Europe.
One may wonder as to how these pesticide residues
get into bottled water that is manufactured
by several big companies. This can be
traced to several facts. There is no regulation
that the bottled water industry must be located
in ‘clean’ zones. Currently the manufacturing
plants of most brands are situated in the dirtiest
industrial estates or in the midst of agricultural
fields. Most companies use bore wells to pump
out water from the ground from depths varying
from 24m to even 152 m below the ground.
The raw water samples collected from the plants
also reveled the presence of pesticide residues.
This clearly indicated that the source of pesticide
residues in the polluted groundwater are
used to manufacture the bottled water. This is
despite the fact that all bottled water plants use
a range of purification methods. Thus obviously
the fault lies in the treatment methods used.
These plants use the membrane technology
where the water is filtered using membranes
with ultra-small pores to remove fine suspended
solids and all bacteria and protozoa and even
viruses. While nanofiltration can remove insecticides
and herbicides it is expensive and thus
rarely used. Most industries also use an activated
charcoal adsorption process, which is effective
in removing organic pesticides but not heavy
metals. To remove pesticides the plants use reverse
osmosis and granular activated charcoal
methods. Thus even though manufacturers
claim to use these process the presence of pesticide
residues points to the fact that either
manufacturers do not use the treatment process
effectively or only treat a part of the raw
water.
The low concentration of pesticide residues in
bottled water do not cause acute or immediate
effect. However repeated exposure even to extremely
miniscule amounts can result in chronic
effects like cancer, liver and kidney damage,
disorders of the nervous system, damage to the
immune system and birth defects.
Similarly six months after CSE reported pesticide
residues in bottled water it also found these
pesticides in popular cold drink brands sold
across the country. This is because the main ingredient
in a cold drink or a carbonated nonalcoholic
beverage is water and there are no
standards specified for water to be used in these
beverages in India.
There were no standards for bottled water in
India till on September 29, 2000 the Union Ministry
of Health and Family Welfare issued a notification
(no759(E)) amending the Prevention of
Food Adulteration Rules, 1954. The BIS (Bureau
of Indian Standards) certification mark became
mandatory for bottled water from March 29,
2001. However the parameters for pesticide
residues remained ambiguous. Following the
report published by CSE in Down to Earth, Vol
11, no. 18, a series of Committees were established
and eventually on 18th July 2003 amendments
were made in the Prevention of Food
Adulteration Rules stating that pesticide residues
considered individually should not exceed
0.0001mg.lit and the total pesticide residues will
not be more than 0.0005 mg/lit that the analysis
shall be conducted by using internationally
established test methods meeting the residue
limits specified herein. This notification came into
force from January 1, 2004.
A case study of river pollution in India
Almost all the rivers in India are polluted. The
causes of pollution may also be more or less similar.
This is a case study of the river Damodar as
reported in Down to Earth. The 563 km long
Chapter5.p65 154 4/9/2004, 5:09 PM
Pollution 155
Damodar river originates near Chandwa village
in the Chhotanagpur hills in Bihar’s Palamau
district. It flows through one of the richest mineral
belts in the world before draining into the
Hooghly, about 50 km south of Calcutta. Indian
industry depends heavily on this region as
60 percent of the coal consumed in our country
comes from the Chhotanagpur belt. Coal based
industries of all types dot the area because of
locational advantages and the easy availability
of water and power. In addition various industries
such as the steel, cement, fertilizer and
explosive plants are also located here. The river
Damodar is polluted with minerals, mine rejects
and toxic effluents. Both its water and its sand
are infested by coal dust and waste from these
industries. There are seven thermal power plants
in the Damodar valley. The states of Bihar and
West Bengal depend almost entirely on this area
for their power requirements. These power
plants not only consume a lot of water but also
dump ash in the valley.
Mining
As underground mines cannot keep pace with
the rising demand, 60 percent of the coal extracted
from the area comes from open cast
mines which are responsible for serious land
degradation. The disposal of rock and soil extracted
along with the coal only adds to the
problem.
Industries
The industries in the area do not have proper
effluent treatment plants. Among the big coal
based industries the washeries account for the
bulk of the pollution in terms of the total suspended
solids (TSS), oil and grease. About 20
percent of the coal handled goes out in the form
of slurry which is deposited in the ponds outside.
After the slurry settles, coalfine (the sediment)
is collected manually. Due to inadequate
retrieval methods very often the water discharges
into the river from the pond carries high
amounts of fine coal particles and oil thus polluting
the river. The other major coal based polluters
are the coke oven plants that heat coal to
temperatures as high as 1100o
C in the absence
of oxygen to prepare it for use in blast furnaces
and foundries. The volatile components in the
coal are removed, leaving hot, non-volatile coke
in the oven which is washed with huge quantities
of water. This water that contains oil and
suspended particles is then discharged into the
river.
Flyash from the thermal power plants
Only one of the thermal power plants has an
electrostatic precipitator to collect the fly ash
while the other just make do with mechanical
dust collectors. As most of these plants are located
on the banks of the river the fly ash eventually
finds its way into the river. The bottom
ash from the boilers is mixed with water to form
a slurry which is then drained into ash ponds.
Most of the ponds are full and in several cases
the drainage pipes are choked. The slurry is
therefore directly discharged into the river.
Effects
The river and its tributaries are the largest source
of drinking water for the huge population that
lives in the valley. On April 2, 1990 about
200,000 litres of furnace oil spilled into the river
from the Bokaro Steel Plant. This oil traveled
150 km downstream to Durgapur. For a week
after the incident five million people drank contaminated
water in which the oil levels were 40
to 80 times higher than the permissible value of
0.03 mg/l.
The Damodar Action Plan an end-of-the pipe
pollution treatment scheme seeks to tackle effluents.
One viable option could be to switch to
less polluting industries and cleaner technology.
This would need strong Government initiative
and also a mass movement by people.
A case study of pesticide pollution in India
Reviewed by শ্রী শ্রী সত্যনারায়ণ নমঃ
on
November 09, 2018
Rating:
No comments: