Production and Use of Pesticides in Asia
Chemical pesticides are an essential ally in the farmers' struggle to protect his crops from diseases, insects and weeds. However, there is growing concern about their impact on the environment and human health, including the health of the farmers who use them.
Introduction
The Center has been working with the Asian Productivity Organization (APO) to collect information about the region's pesticide problems and what can be done about them. A survey was carried out by FFTC and APO in 1997 on pesticide production and use in selected countries in Asia.
One of the main findings was the need for better information. For example, some countries lack effective regulations covering pesticide sales and use, including the registration of new pesticides. This means that new products may come onto the market without either the government or farmers having any clear idea how toxic they may be, or what is the safe level of exposure. Sharing information on pesticide policies and regulations would do a great deal to make the region's pesticide use safer and more effective.
In December 1998, FFTC and APO held a meeting in Tokyo to discuss the results of the survey and present in-depth reports on pesticide production and use in 19 countries. There were also keynote papers on particular problems. These are being published by the Center as Extension Bulletins 466-469.
Integrated Pest Management (Ipm)
IPM is now a very popular concept in pest control. It is favored by both government and development agencies throughout the world. Although the concept of IPM is very attractive, in practice IPM programs can be difficult to implement. For the concept to become a reliable set of practical technologies, further study is needed.
The kinds of technology which are integrated into an IPM control package differ from site to site. Also, to apply IPM, farmers need to be well informed, and must coordinate their pesticide use over a wide area. They need good leadership and technical support. Becasue of these difficulties, although there are many IPM programs in the region, in most countries only a small percentage of farmers are involved in them.
Indonesia has been a pioneer in the use of IPM, and its success shows what can be done with this approach. Since 1989, Indonesia has carried out a number of successful IPM programs to control rice pests, and also vegetable pests such as diamondback moth.
Biological Pest Control
Usually the IPM approach includes non-chemical methods such as biological control. The use of natural enemies such as predators and parasitoids is widely accepted. So is the use of insect sex pheromones, and of microbes and fungi which cause diseases in insect pests. More controversial are transgenic crops, which incorporate genes from other species to enhance disease and pest resistance. Transgenic crops are so new that it is too soon to know whether this method causes long-term or indirect damage to human beings or the environment.
At present, most transgenic crops are being produced by large multinational companies. It would be better for Asian countries to develop biological products themselves, rather than be forced to rely on expensive imports. One recommendation from the FFTC/APO meeting was that the development of biopesticides in the Asian and Pacific region should focus on indigenous biological resources, and low-cost, on-farm methods of production.
Trends in Pesticide Use
Rates of pesticide use are still increasing, although they are tending to stabilize in industrialized countries where application rates are highest. During the initial stage of pesticide use, farmers tend to use mainly insecticides. At later stages, there is greater use of herbicides to replace hand weeding.
As we might expect, rates of pesticide use are highest in the region's highly industrialized countries, who make most of the pesticides they use.
Pesticide Policies
There has been a policy shift over the last decade. In the 1970s and 1980s, it was national governments who were mainly responsible for pesticides in the region. Pesticides were produced or imported by government agencies, and were distributed at controlled prices through official channels, often through the national cooperative movement. During the 1990s, the private sector took over this role. In nearly all Asian countries, it is now private companies which manufacture, import and distribute pesticides.
What effect has this had on farmers? It has given them a wider range of products to choose from, although they may have to pay more for them. A major problem in some countries is that most of the information farmers receive about a pesticide comes from the chemical company which makes it.
An important recommendation from the meeting was that training courses should be expanded to include the village level retailers, and that farmers should be able to get more information about pesticides from the mass media. Labeling of products also needs improvement.
Resistance Management
Resistance management is a key concept in efficient pesticide use. Pesticides should be used in such a way that the development of pest resistance is prevented, or at least delayed as long as possible. Farmers should avoid frequent, repeated applications of the same pesticide. Instead, they should alternate different products. In this way, pest populations do not have time to build up resistance to any one product.
There is something of a conflict between commercial interests and the need to avoid pest resistance. By promoting their products, chemical companies are striving to dominate the market. If they succeed, all local farmers will be using the same product. This is exactly the way to promote the development of pest resistance!
Banned and Restricted Pesticides
A major concern is the use of highly toxic and dangerous pesticides. Many of these are imported from Western countries who have banned their own farmers from using them, because they are so dangerous. Participants at the meeting emphasized the value of toxicity data, and hoped that the different countries in the region would find some way of sharing this data.
Of course, chemical companies developing new pesticides carry out toxicity tests before they put them on the market. However, the results are a commercial secret - the companies do not have to make them public. Naturally enough, there tends to be selective disclosure. Companies make public only the data which gives a favorable picture. National governments must carry out their own toxicity tests before a pesticide can be registered. This testing is a heavy burden on countries which have only only limited funds and personnel for testing.
The &Quot;Dirty Dozen&Quot;
Still being sold in the region are many of the 18 very hazardous pesticides popularly known as the "Dirty Dozen". Linked to cancer, birth defects and other health problems, they break down very slowly in the environment and are taken up in the food chain. Among the "Dirty Dozen" are well-known pesticides such as DDT, paraquat, dieldrin and 2,4,5-T.
They have been banned in more than 100 countries, but are still being sold and used in many countries of the region. In spite of their dangers, it is not easy to discontinue their use. DDT and some of the other products are widely used in public health programs e.g. for spraying mosquitoes. Even though they might be banned for agricultural use, it is still easy for farmers to get hold of them if they want them.
The most serious problem is that many farmers prefer them! According to the FFTC/APO survey, a list of the twenty most popular chemical pesticides used by farmers in the region includes a substantial number of the Dirty Dozen. These pesticides are cheap and effective, and farmers don't understand how dangerous they are.
It is important to educate farmers about the risks, as well as the benefits, of pesticides. Also, if pesticides are to be banned, farmers must be given safer alternatives which are as effective, and which cost about the same price.
Conclusion
Asian farmers are showing a growing interest in organic farming and biological control. This is more because of the demand for organic products than because organic farming methods offer a more effective kind of pest control. In the present state of technology, farmers still need to use chemical pesticides, especially in tropical countries
To a large extent, the damage to health and the environment from chemical pesticides is caused, not so much by pesticide use, as by pesticide misuse. For the present, rather than replacing pesticides with biological methods, the most practical goal might be to improve the use chemical pesticides.
Some of the ways to achieve this are better timing of applications, rotating the pesticides used to avoid the development of resistance, and the use of safer formulations. Another important step is improving application technoloy, including the nozzles of sprayers. If the holes in nozzles are blocked or too large, the farmer cannot avoid applying too much pesticide.
The meeting showed the value and import-ance of regional data collection and data sharing. As a regional information center, FFTC hopes to assist in this work. Participants at the meeting were particularly interested in exchanging data about pesticide registration, biological pesticides, banned and resticted pesticide products, toxicity data and pesticide resistance.
Index of Images
Figure 1 Field Trip to Yasato Farmers' Cooperative, Japan, Which Sells Direct to Consumers<BR>
Figure 2 Producers Certificate from the Yasato Farmers' Cooperative. . It Shows What Pesticide (If Any) Was Used on the Crop.
