Health Hazards, Environmental Effects
and Externalities of Pesticide Use in Pakistan
1. Introduction
PESTICIDES
have played an important in enhancing crop yields through
insect pest control. However, their improper and excessive use
has been the cause of serious health hazards. It was in 1962,
when Ms Rachel Carson in her classic book “Silent Spring”
highlighted the harmful effects of pesticides on environment.
The subject has assumed greater importance today than ever
before because of pesticides hazards to human health and
environment. Only recently government was in the process of
disposal of 2,000 tones of expired toxic pesticides, many of
them banned worldwide, imported by the Ministry of Agriculture
about four decades ago.
Pesticide use began in Pakistan in the 1950s for locust
control. In 1954, the government imported formulated
pesticides amounting to 254 tones (Habib, 1996). This was the
beginning of the pesticide business in the country. Until
1980, the Plant Protection Department was responsible for
pesticide imports and their distribution in the country
through the national agricultural extension network. Most of
the pesticide imports were used for aerial spraying to control
locust, pests of sugarcane, cotton, rice, tobacco and fruit
crops. The cost of pesticides was subsidized and aerial
spraying was free of charge.
Pesticides were privatized in 1980 and since then there has
been a steady increase in pesticides import and consumption.
As a result, consumption of pesticides in Pakistan has
increased from 665 tones in 1980 to 14,773 tunes in 1990 and
61,229 tones in 2000 worth about 7.7 billion rupees (Ahmad et
al, 2002). Unfortunately, the widespread use of pesticides has
resulted in complicating pests’ problems. Excessive and
inappropriate pesticide use has disturbed the agro-ecosystem
and killed non-target and environment-friendly organisms,
including and environment-friendly organisms, including birds.
Besides this, the excessive inappropriate use has induced pest
resistance and resurgence. Studies show that the populations
of natural enemies in cotton growing areas have declined as
much as 90 percent during the last decade (Husnain, 1999). It
is therefore high time that the use of pesticides be
rationalized and alternative approaches promoted.
2. Pesticide Use in Cotton Production
While insect pests damage almost all crops, cotton is much
more susceptible to their attack and successful cotton
production is largely dependent on the use of pesticides. In
recent years, cotton leaf curl virus, created havoc and
resulted into cotton failure, while white fly (Bemesia tabaci)
and American bollworm (H. armigera) took the epidemic forms in
1996 and 1997-1998, respectively.
Further, more than 50 percent of all pesticides are used on
cotton in Pakistan and their indiscriminate use has provoked
outbreak of secondary pests. The average number of
applications with insecticides in cotton has increased
significantly since the 1990’s. It has reached a level that
may be uneconomical given the only moderate yield levels. Five
to six applications of pesticides in Punjab constitute, about
40 percent of the total variable cost of cotton production
(Ahmad et al, 2002).
3. Health Hazards of Pesticides
Pesticides enter the human body through three routes: the
skin, lungs and the digestive system. Poisoning can be acute
or chronic depending on the intensity and duration of
exposure.
The
effects of chronic exposure include various forms of cancer,
adverse reproductive outcomes, impaired immune functions
neuropathies, neurobehavioral disorders and allergic
sensitisation reactions, particularly of the skin (Repetto and
Baliga, 1996). Chronic pesticide poisoning can be measured
either by Cholinesterase levels in the blood or pesticide
residues in blood, fatty tissues and mother’s milk.
3.1 Health Hazards for Women Cotton Pickers
The gender implications of health hazards associated with
pesticide use are far from neutral. Traditionally women carry
out Cotton harvesting in Pakistan. As production has grown
more pesticide intensive, these women are increasingly exposed
to large amounts of highly toxic chemicals. Cotton is sprayed
heavily during the season and in a number of cases immediately
before harvesting. The cotton-picking season starts in the
middle of October and extends to the end of December. Fear of
pests such as White fly and American Bollworm prompt farmers
to use pesticides even during the cotton-picking period. While
these late sprays are largely wasted in terms of improving the
quality of the crop or increasing yields (Orphal 2001); late
sprays also have serious implications for cotton pickers.
Table 1: Quantitative Evidence
of Pesticide Health Hazards
Exposure during application at farm level
1) |
-
Households affected per season
-
Work days lost per crop season
-
Health treatment costs (Rs/year)
-
Number of deaths |
63%
2-90
100-3000
1/8000
households |
Exposure during cotton harvest
2) |
-
Pickers experienced sickness
-
Average work days lost per crop season
-
Treatment costs (Mill.Rs.)
-
Value of Work lost (Mill.Rs.) |
87%
5
105
660
|
Exposure at local pesticide refilling
facilities 3) |
-
Labourers experiencing sickness
-
Work days lost (per year)
-
Treatment cost (Mill.Rs.)
-
Value of Work lost (Mill.Rs.) |
50%
6
0.46
0.09 |
1) Estimated for 217 million
households of 9 major cotton districts in Punjab.
2) Estimated for 5127 thousand tons of cotton picked by 2.6
million women
3) Estimated for 1000 labourers working at 25 plants in Multan
City
Source: UNDP
2001
Women farm workers are not only engaged in some of the highest
risk tasks, but they also have less access to information
regarding the dangers of exposure to pesticides. Jabbar and
Mohsin (1992) report that 68% of female pickers are not aware
of the health effects of pesticides and 95% do not take any
precautionary measures. Male farm workers, by way of contrast,
were apparently more aware of the risks and also more likely
to protect themselves: 86% of men surveyed seemingly
understood the health impact of pesticides and 82% considered
themselves to be actively taking precautionary measures when
using pesticides or working in sprayed fields.
About 2.6
million women pick cotton from the 9 major cotton-growing
districts of Pakistan. Studies on health hazards to women
cotton pickers show that in Pakistan about 2.23 million women
annually may get sick from exposure to pesticides. Measured in
terms of mitigation costs the amount they spend on treatments
to restore their health is substantial relative to their low
income. An estimated average of five days work loss per worker
per year for the 2.23 million-pickers results in an
accumulated 11 million days of work lost, amounting to Rs. 660
million. Adding up health treatment costs and lost labour days
amount to a total of Rs. 765 million health externalities
(table 1).
3.2
Pesticide Applicators
Although many
farmers in principle know about the potential hazards from
pesticides their actual behaviour in handling and spraying is
not always in conformity with their knowledge. Their
inadequate response in terms of protective measures undertaken
precisely reveals this notion which shows their restricted
understanding of the pathways by which pesticide contamination
can occur. Therefore, farmers who apply pesticides are also
affected by serious health hazards.
. About 63% of farm workers get sick every year with workdays
lost per crop season per person range from 2-90 with treatment
cost ranging from Rs. 100-3000 per year.
The evidence
from hospitals and survey results shows the occurrence of
quite a large number of acute poisoning cases in the cotton
zone of Punjab. The result shows that about every second
household has reported pesticide-related sickness (UNDP 2001).
Organophosphorous compounds will most likely continue to be
the most heavily used insecticides used in developing
countries. Unless appropriate policies are being put in place
the use of chemical pesticides will probably more than double
over the next 10 years. Despite the prevalence of these highly
toxic chemicals there is still no regular program for
monitoring the health of the workers involved in handling
pesticides in Pakistan (Inayatullah and Haseeb, 1996).
4.
Pesticide Residues in Food and the Environment
Although
monitoring of residues in domestically consumed food products
is rather irregular the few available analyses provide a cause
for concern
In one recent
study (Ahad et al, 2001) samples were taken of four different
vegetables: okra (Hibiscus esculentus), brinjal (Solanum
melongena), gourd (Citrullus vulgaris) and bitter
gourd (Momordica charantia) (table 2). Not
surprisingly, pesticide residues were found in all vegetable
samples. In 60% of the samples contamination exceeded the
respective maximum residue limits (MRL). Pesticides found to
be above their MRL values were carbofuran, dichlorvos,
methyl-parathion, fenitrothion and azinphos-methyl. However,
pyrethroids such as deltamethrin and cypermethrin recommended
for use on cotton were not detected in any sample.
Table 2
:Pesticide Residues in Food Chain
Type of
Sample |
% of
samples contaminated |
% of
samples >MRL |
Vegetables (Brinjal, okra,
bitter gourd, gourd) |
100 |
60 |
Fruits
(apples) |
100 |
60 |
Cotton
seed oil |
100 |
65 |
Cotton
seed cake |
100 |
65 |
Shallow
ground water |
100 |
30 |
Source: Ahad
et al, 2001
Increased
pesticide resistance in pest populations resulted in
additional applications of pesticides to maintain expected
cotton crop yields. This becomes more obvious during pest
outbreaks, which results in serious set back to crop
production, for example, the case of cotton in 1992 or 1996
(Ahmad 1999). The consequences are lower yields and higher
production costs in cotton with far-reaching effects on
Pakistan's economy, reducing economic growth.
Beside
resistance, a growing concern of pesticide use is their impact
on biodiversity. Pearce and Tinch, (1998) indicate that yet
this is the subject about which least appears to be known. For
instance pollinator damage is relatively better understood
than depletion in soil fauna due to pesticide overuse. The
idea of biodiversity and its economic value has not been
addressed adequately in the literature. The analysis of
biodiversity externalities from the standpoint of economic
analyses is also unsatisfactory and need rigorous analyses.
5. Externalities of
Pesticide Use and Cost to the Society
A comprehensive study by UNDP
(2001) provides an assessment of the effects of pesticides on
human health, natural resources and the environment (table 3).
The total cost of pesticide-related externalities in Pakistan
is almost Rs. 12 billion per annum for nine districts of
cotton. Thus, pursuing a rational pesticide policy is not just
the right to do for the heath of Pakistanis and for the heath
of Pakistanis and for cleaner environment: but it is also
makes economic sense. The monetary value of the adverse
effects of pesticide on human, natural resources, food chain,
production losses and domestic animal poisoning suggests that
the costs of pesticides to the Pakistani economy and society
are substantial.
Table 3:
Summary of external Costs of Pesticide Use in Pakistan
Externality Category |
Rs
Millions |
Health:
Applicators
Pickers
Industry
Distribution |
833
42
765
0,6
25 |
Pesticide Residues: |
110 |
Production:
Pesticide
Resistance
Animal
Loss
Wild
Honeybee loss |
7034
5667
1304
63 |
Biodiversity Loss |
3745 |
Health
Environmental Monitoring : Residue Analysis (6) |
6 |
Public
Awareness: Extension, Media, NGOs |
14 |
Total Externality (million Rupees per year) |
11,742 |
Source: Ahmad
2002
6. Building Consensus for Action
In view of the pesticide hazards,
there is an urgent need to disseminate information on the
hazards of pesticides, on their proper and rational use, and
how to protect individuals, families and communities from
their hazards. Besides, integrated pest management practices
should be widely promoted. For this purpose there is need to
train extension workers and farmers in IPM. This will help in
creating a cleaner, safe environment for future generations.
7. References
Ahad,
K., Hayat, Y., and Ahmad, I. (2001). Capillary Chromatographic
Determination of Pesticide Residues in Multan Division. The
Nucleus 38(2):145-149.
Ahmad, I., Khan, M.A., Soomro, M.H. and Waibel,
H. (2002). Pesticides hazards for health and environment.
Farming Outlook October-December 2002, pp.14-16.
Habib, N.
(1996): Invisible Farmers: A Study on the Role of Woman in
Agriculture and Impact of Pesticides on Them, Khoj Research
and Publication Centre, Lahore, Pakistan, pp.129
Hasnain, T. (1999): Pesticide Use and its
Impact on Crop Ecologies: Issues and Options. SDPI Working
Paper Series, SDPI, Islamabad, pp.73
Inayatullah, C. and Haseeb, M. (1996):
Poisoning by Pesticides, Pakistan Journal of Medical Research,
35(20): 57-58
Orphal, J (2001): Economics of Pesticide Use in
Cotton Production in Pakistan, Diploma Thesis, University of
Hannover, Germany
Pearce, D. and Tinch, R. (1998): The true Price
of Pesticides. In. Vorley, W. and D. Keeney (eds. 1998: bugs
in the System- Redesigning the Pesticide Industry for
sustainable Agriculture, Earthscan, London, pp.51-93
Repetto, R. and Baliga, S.S. (1996): Pesticides
and the Immune System: The public Health Risks, New York,
World Resources Institute, USA
UNDP 2001: Policy and Strategy for the rational
Use of Pesticides in Pakistan, Building Consensus for Action,
UNDP / FAO Paper, Rome, Italy.
Dr. Iftikhar Ahmad, Deputy Director General/National IPM
Coordinator, Institute of Plant and Environmental Protection,
National Agricultural Research Centre, Islamabad, Pakistan
Dr. Shazia Iram, Assistant Professor, Department of Mycology
and Plant Pathology, University of the Punjab, Lahore,
Pakistan
Dr. Muhammad Azeem Khan, National IPM Programme, NARC,
Institute of Plant and Environmental Protection, National
Agricultural Research Centre, Islamabad, Pakistan
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