Investigating the Impacts of Pesticide Use in the Mekong Delta
Catherine Wheeler
The Mekong Delta of Viet Nam is one of Asia's most fertile rice growing
areas. Economic incentives, improved rice strains, greater market
access, and technological innovations now enable the region to produce
up to three crops per year  depending on land and irrigation
conditions  versus one to two annual crops in the past.
But this productivity increase has been accompanied by a dramatic
increase in the use of pesticides per hectare of farm land. Vietnamese
farmers believe that the more pesticides they use, the higher their
rice yield will be. In fact, pesticide overuse results in unnecessary
expenditures, while increasing the exposure of both humans and the
environment to potentially harmful levels of agrochemicals. Possible
environmental impacts include the destruction of rice/fish culture
(farmers raise fish in the flooded paddy fields to augment their diet
and income); the killing of beneficial animals that prey on rice pests;
and air and water pollution.
Economic and health impacts
A recent study by Nguyen Huu Dung, coordinator of the Environmental
Economics Unit at Viet Nam National University, explored the economic
and health impacts of prolonged pesticide use in the Mekong Delta. The
study involved 180 farmers, who were surveyed during the 1996
winter/spring rice growing season. It was financially supported by the
Economy and Environment Program for South East Asia (EEPSEA), which is
sponsored by the International Development Research Centre and eight
other donors.
Mr Dung found that more than 90% of farmers in the Mekong Delta use
pesticides (such as insecticides, herbicides, fungicides, and other
chemicals), including several products that have either been banned or
restricted because of their toxicity. Although approximately 65% of the
surveyed group are able to read instruction labels, just 39% actually
understand and follow the directions. As a result, most farmers do not
wear protective equipment such as rubber boots, face masks, and long
sleeves, preferring to work in traditional shorts and singlets
(sleeveless t-shirts). More people would wear protective gear, however,
if it was comfortable and freely available.
The study revealed that more than half of those surveyed were very
concerned about the effects of pesticide exposure on their health. Out
of the 180 farmers, 41.8% had experienced headaches, 26.2% had
experienced dizziness, and 31.4% had experienced skin irritation. Other
frequent symptoms included eye irritation, fatigue, and trouble
Integrated pest management
Mr Dung also examined differences in pesticide application between
Vietnamese farmers who practice integrated pest management (IPM) and
those who do not. In 1992, Viet Nam's Plant Protection Department, part
of the Ministry of Agriculture and Rural Development, launched an IPM
training program to help farmers combine natural and chemical pest
control methods. The study found that the training program has had a
significant impact on pesticide use. For example, the proportion of
farmers using banned pesticides, such as methyl parathion, has declined
from 36% in the 1994 dry season planting to 4.5% today.
Other results showed that farmers without IPM training use an average
of 1,081 grams of the active ingredient of pesticide per hectare. By
comparison, IPM-trained farmers use significantly less pesticide (884
grams of active ingredient), choose safer pesticides, and reap larger
harvests at the end of the season. In addition, IPM-trained farmers are
more likely to wear protective equipment when spraying pesticides and
suffer fewer symptoms. "It's very important for Viet Nam to continue
expanding the IPM program," Mr Dung concludes. "IPM is an effective
tool for changing farmers' perceptions and decreasing pesticide use in
rice production."
Reducing pesticide use
To further reduce unnecessary pesticide use in the Mekong Delta, he
recommends that pesticide retailers be trained and licensed to dispense
only the least hazardous pesticides  and that older, extremely
hazardous stocks be phased out. Mr Dung also advocates a tax on
pesticides, along with other disincentives.
"If the price of pesticide goes up, farmers will use it less often and
perhaps more strategically," he explains. "Although [rice yields] will
be somewhat lower, they will actually benefit from using less pesticide
by saving substantially on labour, health, pesticide, and fertilizer
Catherine Wheeler is a freelance writer and editor based in Singapore.
[Photo: C. Andrew, CIDA]
Resource Person:
Nguyen Huu Dung, Coordinator, Environmental Economics Unit, Viet Nam
National University, 01 Bis Hoang Dieu Street, Phu Nhuan District, Ho
Chi Minh City;
Tel: (848) 844-8222 or 862-6229; Fax (848) 824-1186; E-mail:
[email protected]
February 20, 1998
BBC, 6/2/01 - Pesticide use has risen alongside agricultural expansion
By Owen Bennet-Jones in Hanoi
Hospitals in Vietnam are reporting large numbers of poisoning cases
caused by a misuse of pesticides.
Doctors say they treat hundreds of pesticide-related cases each year
and that some patients die as a result of pesticide poisoning.
A hospital in Ho Chi Minh city says that last year it dealt with nearly
50 fatalities, mostly of farmers who have misused weed and insect
With the introduction of market mechanisms over the last 10 years,
agricultural production in Vietnam has sharply increased and the
country is now a significant exporter of rice and coffee.
The agricultural boom has been accompanied by a huge increase in the
use of pesticides.
Smuggling clampdown
But many farmers ignore the instructions that come with pesticides and
believe that if they use more of the chemicals then the effect will be
In addition they often ignore warnings about the need for protective
clothing when using pesticides.
According to Vietnamese newspapers the government has tried to regulate
the pesticide industry and in particular to clamp down on the use of
illegal pesticides, many of which are smuggled into Vietnam from China.
Despite the official efforts to control the situation the newspapers
regularly carry reports of pesticides being misused.
In the Mekong Delta, for example, it's feared that the over use of
chemicals to kill a plague of snails has led to widespread pollution
and damage to the water supply.
Doctors say that some of the victims of pesticide poisoning are
consumers who've eaten fruit and vegetables with too many chemicals on
them but most cases involve the farmers who actually work with the
* Vietnamese farmers suffer from pesticide poisoning
BBC, 6/2/01 - Hospitals in Vietnam are reporting a growing number of
poisoning cases caused by a misuse of pesticides.
Doctors say they treat hundreds of patients each year.
Most of the victims are farmers who've misused weed and insect killers.
Patients experience vomiting and low blood pressure and in more serious
cases die from the poisoning.
The BBC Hanoi correspondent says the introduction of market mechanisms
over the last ten years in Vietnam has led to an agricultural boom
which has been accompanied by a huge increase in the use of pesticides.
He says many farmers ignore the instructions that come with the
chemicals and often disregard warnings about the need for protective
clothing when using them.
[email protected]