Frequently Asked Questions About Pesticides
A poison used to kill a plant or animal which some humans consider a pest. Pesticides are sometimes classified according to what they kill - insects (insecticides), plants (herbicides), moulds (fungicides), and so on.
More than one pound (0.453592 kg) of pesticide is manufactured each year for every man, woman and child on the planet. And the amount used is increasing rapidly. The global agrochemical sales for 1997 was US$ 29,540 million, increased to US$ 31,000 million in 1998 and totalled up to US$ 30,070 in 1999.
Yes, but:
Acute toxicity occurs when the poisonous effects of the pesticide are felt right away. Whereas chronic toxicity occurs when the poisonous effects of the pesticides on the health are delayed. That is, they take a long time to develop and these long-term effects may not occur until after months or years of exposure to the pesticide.
Local acute effects are those that affect only the parts of the body the pesticides comes in direct contact with. Local acute effects can be irritant effects such as dryness, burning, redness, and itching of the eyes, nose, throat and skin; watering of the eyes, and cough. Or they can be skin problems, such as redness, itching, burning, rashes, blisters and discolouration. A common symptom of pesticide poisoning is when fingernails and toenails turn black or blue. In bad cases, the nails will even fall off.
Systemic effects of pesticide poisoning occur when the pesticide gets inside the body and affects the whole system. The blood carries the pesticide to all the parts of the body and can affect the eyes. heart, lungs, stomach, intestines, liver, kidneys, muscles, brain and nerves.
Because it is ethically unacceptable to test pesticides on humans, animals such as rats and mice are used. The effects on these animals are not always the same as on humans. Sometime they are affected more, sometime less. In the case of the drug thalidomide, test animals were unaffected, whereas humans suffered tragic birth abnormalities. Chemicals causing cancer in animals are not always men, with the possible exception of arsenic, also do so in experimental animals, generally rodents.
For most of us, the primary exposure is what we eat and drink. Maximum Residue Levels (MRL) and Acceptable Daily Intake (ADI) are measures set by governments to assure us that human exposure to pesticides is limited. But there is no fool-proof way to ensure a safe universal ADI, because of the diversity of foods we eat and because some people are more vulnerable than others - especially young children and the malnourished, MRLs and ADIs also do not take into account the effects of combinations of pesticides or of pesticide breakdown products.
Often food is not tested before consumption. In December 1987, 116 people were poisoned in Hong Kong when they ate spinach contaminated by methamidophos. And hundreds of people in California, U.S. became ill after eating watermelon grown in fields illegally treated with aldicarb.
Some pesticides, especially DDT have been useful in controlling mosquitoes carrying malaria. But overuse of insecticides in farming has caused mosquitoes to develop resistance, leading to a resurgence of malaria in many parts of the world. In Sri Lanka during the 1960's public health programmes using pesticides helped bring about a drop in malaria cases from 3 million to 25. By the early 1970s, however, DDT-resistant mosquitoes started to push infection levels to new levels.
Ironically, pesticides may now be a more serious health concern than malaria in some countries. Malaria did not cause a single death in 1978 in Sri Lanka, yet at least a thousand people died from pesticide poisoning.
For long-term control, non-chemical methods may well be more effective than the `quick fix' use of pesticides. Sri Lanka's self-help Sarvodaya movement has had considerable success mobilising villagers to identify breeding sites of malaria?bearing mosquitoes and then drain, fill, or apply oil films to the breeding sites.
Pesticides can become concentrated, perhaps to toxic levels, via the food chain. Thus, an insect feeding on plant sprayed with pesticides might be eaten by another insect which might then be eaten by a bird. This is especially a problem with pesticides that are fat-soluble and highly persistent, including DDT and other organochlorines.
Traces of pesticides too small to kill the targeted pest can accumulate to levels high enough to harm species further on up the food chain. In the early 1970s, hundreds of people in South India - all poor and of low caste ? were afflicted with a mysterious, painfully crippling disease. Investigations finally determined that the condition was caused by eating pesticide-contaminated crabs scavenged from sprayed rice fields.
Many pesticides do break down rapidly in the environment, but others - like DDT and dieldrin - can remain toxic for 20 years or longer, continuing to kill insects and harm other organisms. The breakdown products of some pesticides - aldicarb and malathion, for instance ? can be more toxic than the parent compound.
Under the hot and humid conditions found in many Third World countries, persistent pesticides apparently break down more quickly, but bioaccumulation can still take place.
Until pesticide residues started turning up in drinking water wells, most people believed groundwater was protected from contamination by soil and rock formations. By 1986, a total of 19 different pesticides applied in agriculture had been detected in groundwater in 24 out of the U.S.'s 50 states. Some towns must bring in bottled water from other sources because their communities drinking well is contaminated.
No, pesticide particles can be carried thousands of miles via wind, rain, snow, or surface water. Today virtually all human beings contain some organochlorine pesticide residues in the fatty tissues of their bodies. Even seals in the Antarctic - thousands of miles from where pesticides are used - have DDT residues in their bodies.
No. The world currently produces more than enough food for everyone on the planet. The problem is not insufficient production, but that poor and hungry people lack the means to pay for or to grow the food they need. Agricultural chemicals cannot solve that problem.
The Green Revolution did dramatically increase yields but only with costly combinations of high?yielding seeds, fertilisers, pesticides and irrigation. Wealthier farmers - able to buy in volume and with greater access to credit - benefit more from its technologies than small peasant farmers, who cannot afford the required inputs. Ten years after the Green Revolution came to a Philippines rice-growing village dominated by a few large landowners, the farms had grown by 50 percent, displacing many smaller farmers. Furthermore, most pesticides used in the Third World(70 percent, says one study) are applied on luxury crops grown for export to the U.S., Europe and Japan and not on basic foods for hungry people.
Farmers have always sought better methods of controlling the insects, diseases and weeds that threaten their crops. Many turn to pesticides as an `easy solution' to an age-old problem, and discarded traditional pest control technique. The pesticide industry and government agricultural ministries aggressively promoted this move as modern and `better', neglecting to inform users about the hazards and drawbacks of chemical pest control.
Today many farmers in the Third World, the U.S. and Europe are disillusioned with chemical pest control. They are growing crops with little or no pesticides. Their success at maintaining high crop yields and increasing profits shows that pesticides are not the 'best' pest control method.
At first, chemical pest control seems cheap and effective, but pesticides tend not to work in the long run. Pest inevitably develop resistance to the very chemicals aimed at them. Because the natural enemies that once kept the pest under control are usually destroyed as well, the pest multiply to become threats - a phenomenon known as resurgence. In addition, insects never before considered a problem because natural enemies kept their numbers at low levels may emerge as pests.
To combat resurgence and resistance, farmers then apply larger quantities of more powerful (and often more costly) chemicals, beginning an addiction or `treadmill' from which escape is difficult.
While pesticides may provide farmers with short-term against pest damage, the pesticide addiction can also increase farmers' costs beyond the point of profitability. On the other hand, farmers using no pesticide through integrated pest management (IPM) techniques earned almost 50 percent more than farmers spraying on fixed calendar schedules. Thus anyone who advocates economically viable alternatives to chemical pesticides is decidedly pro-farmer.
In the long term we have no choice but to stop using chemical pesticides. Pests are developing resistance to new chemicals faster than ever. In 1944, only 44 insect species were known to be related to insecticides. By 1984, at lease 447 insect species, 100 plant pathogens, and 48 species of weeds had evolved pesticide resistance. In order to keep chemical pesticides effective for future emergency pest control situations, we should greatly reduce their use today.
And alternatives to pesticides are just as effective as pesticides. We need only look to the experiences of the many thousands of farmers in industrialised and developing countries who have freed themselves from dependency on chemicals. They are showing that alternatives like IPM can be put into place immediately, reducing pesticide use by 50 to 70 percent or more with no decrease in crop yields.
IPM has many definitions. At its best, IPM is a scientifically superior means of pest control integrating all available pest control methods, including biological controls and cultivation techniques. Under IPM, populations of pests are carefully monitored. Chemicals are used only when population reach a, threshold where damage to the crop is possible and non?chemical methods will not work in time.
When applied to plots of rice in the Philippines, IPM cut total pest control costs in half, with no loss in yields. Unfortunately, the pesticides industry now uses the term IPM to continue selling pesticides as the `best' method of pest control, retaining only the notion of monitoring to determine when to spray.
Today people working for chemical-free pest control recognised the need for an entirely new perspective, and the concept which is emerging is called `sustainability' . Sustainable pest control recognises that nature is self?regulating, if there is diversity of species. Instead of directly intervening with chemicals, the goal is to enable nature to solve the problem internally.
Sustainable agricultural system are designed as closed resource cycles, beginning with recycling organic matter to build healthy soils. Many traditional land?use systems - like raising fish and edible aquatic weeds in rice paddies - are fertile source of experience and wisdom in achieving sustainability in agriculture.
Perhaps, but only as a last resort. Alternative strategies should be put into place first, and the short and long term effects of any proposed pesticide use fully considered. And al information about the decision should be published for the press and public to review.
Not if current trends continue. Some of the most advanced research in biotechnology is being carried out by the large transnational chemical corporations (TNCs'), with profit as the goal. While some companies are trying to engineer disease and pesticide-resistant crops, others are making crops more pesticide-resistant.
For instance, one of the main 'problem' with herbicides is that they not only kill weeds, but can damage the very crops they are supposed to protect. Because this limits the use (and sale) of herbicides, at least 28 TNCs have launched over 65 research programmes to engineer herbicide?resistant crop varieties. The giant TNC, Monsanto, expects to have cotton varieties resistant to its herbicide 'Roundup' on the market by 1989, and Ciba-Geigy scientist have already identified the gene that will protect crops against one of its most widely sold herbicides, `Atrazine'.
Compared to the potential for profits in commercial crop improvements, TNCs often have little economic intensive to develop pest resistance in the basic food crops needed to feed the world's hungry ? even though this would benefit society more.
Because the chemical industry makes more profits from pesticides than from alternative pest control methods. While profit in itself is not bad, there is cause for concern when the search for more profitable products, and not health or the environment, drives most new agricultural research.
Sustainable pest control not only makes more sense for health or environmental reasons, but because it gives us - as consumers, farmers, or simply concerned citizens - more control over the basic technology that affects our lives today.
The Pesticides Industry is the group of companies that produces and/or sells pesticides. Some of them are giant companies with headquarters in the North. Some are local companies with smaller operations. The largest pesticide companies are very wealthy and very powerful. The top 10 pesticide companies control 85% of all pesticide sales in the world.
The big pesticide companies are Transnational Corporations (TNCs). TNCs are giant companies that have business interests and investments around the world. Some have more wealth than whole countries.
Much of agriculture's current dependency came about because industry's aggressive promotion of pesticides as 'modern' and 'safe' create demand. With European and North American markets approaching saturation, the pesticide industry is now promoting its products heavily to Third World farmers and governments.
In its drive to expand global sales, the pesticide industry has sometimes been shockingly irresponsible. When government of industrialised countries banned some pesticides as too dangerous, the manufacturers simply 'dumped' the chemicals by exporting them to developing countries with less stringent regulations. Particularly atrocious were experiments carried out by Ciba-Geigy in 1975, in which chlordimeform (a carcinogen) was sprayed on Egyptian children in an effort to persuade the Egyptian government to register the pesticide!
The pesticide industry itself has most of the information about the risks of a given pesticide as well as the resources to prevent most misuse and abuse. But without public pressure, they make little effort to do so. Pesticides are still being sold with dangerously inadequate labels and packing, and by poorly trained sales personnel who are keen to sell and therefore give misleading advice.
Yes, in some places. But such training enhance the notion that chemicals are the only effective method of pest control, an approach which promotes industry products. Alternative methods of pest control are seldom on the curriculums.
Pesticide production is capital?intensive, and so is pesticide use. That means that less rather than more people are employed when agriculture becomes chemical-dependent. Where there is a surplus of labour, as is the case in most Third Worlds countries, it simply does not make sense to eliminate jobs by turning to chemicals for pest control.
In contrast, alternative pest control strategies like integrated pest management (IPM) depend more on human expertise and labour.
The Bhopal disaster which left more than 2,000 persons dead and 100,000 injured for life destroyed the myth that the chemical industry claims to have a good safety record. Major accidents in West Virgina, U.S., and in Switzerland shortly thereafter reinforced the fact that pesticide production facilities in industrialised countries are also vulnerable.
The chemical processes needed to produce the active ingredients in pesticides are often highly complex. Unexpected runaway chemical reactions, as at Bhopal, are ever present risk. This risk is compounded by the reluctance of chemical companies to keep surrounding communities fully informed about the hazardous chemicals and process in their midst.
The pesticide industry uses risk/benefit arguments to defend pesticide use. Yet we still do not know about all the way in which pesticides cause harm, partly because industry still controls and withholds much health and safe data. In the light of this uncertainty, shouldn't we err on the side of caution and use fewer rather than more chemicals in our lives?
And we should ask who bears the risk and who really benefits. With any technological change, risks and benefits are distributed according to prevailing social and economic conditions. In the case of pesticides, the rural poor of the Third World are hit hardest by accidental and occupational poisoning (aggravated by lack of basic medical care), contamination of the environment (source of their food and water), and other costs. In contrast, those who benefits are usually already better off, like the large landowners and, of course, the pesticide industry.
While the high yields of chemical-intensive monocultures are impressive, traditional methods of inter-cropping can be just as productive. In the Philippines, for instance, the high yields of Green Revolution rice should be compared to the total amount of nutrition ? fish, crabs, prawns, frogs and edible weeds as well as rice ? available from traditional rice paddies.
And, though pesticides can be effective in the short term, extensive use of agricultural chemicals may be reducing the long-term productivity of the earth. Pesticides and fertilisers can kill soil?building organisms important for soil fertility. Populations of earthworms, for example, are dramatically reduced by most carbamate pesticides.
The pesticide industry can apply great pressure on governments. When several Brazilian states prohibited imports of pesticides banned inn their countries of origin, the industry mounted a massive legal attack until Brazil's highest court declare the laws unconstitutional. Fortunately, the national government stepped in with a constitutionally sound ban.
The same government officials who regulate often have vested financial or political interests in maintaining a strong agrochemical industry. And in some countries, including Mexico and India, the government itself is a pesticide manufacturer, importer and/or exporter ? as welt as regulator.
No. Regulatory schemes commonly require that pesticides be registered or licensed before they can be sold within the country. In making licensing decisions, governments use industry-supplied health and safety data to evaluate a pesticide's potential to cause harm. A major scandal broke out in 1983, when the U.S. government revealed that 212 pesticides on the market had been registered with invalid data. A private laboratory, Industrial Bio-Test (IBT) Laboratories, had falsified data or used sloppy lab techniques on two thirds of its safety testing for pesticide companies. At least 25 percent of all pesticide registrations in Canada had also relied on the invalid data, and in many developing countries the percentages are far higher.
All governments should act to protect their citizens from dangerous and inappropriate technologies. But many countries are run by local elites who do not have the interests of the majority of people in mind. And many Third World governments simply do not have the financial resources or trained staff to implement and enforce pesticide controls.
The TNCs and governments of industrialised countries which export pesticides have far greater scientific and financial resources for testing and licensing pesticide use than do their counterparts in developing countries. There is no excuse for the current double standard, which allows pesticides too dangerous for unrestricted use to be exported to developing countries, with minimal notification, if any.
As a first step, all governments should bring their pesticide regulations up to the minimum standards of FAO's International Code of Conduct on the Distribution and Use of Pesticides, unanimously adopted by the 158 member nations of the UN Food and Agriculture Organization (FAO). Exporting counties should implement the principle of 'prior informed consent', which means not allowing a banned, restricted or untested pesticide to be exported without the importing country government's consent.
Governments should also enact 'right to know' laws guaranteeing the right people and communities exposed to pesticides to have full information about those chemicals. And they can ensure access to other vital information by establishing national pesticide poisoning centres and mandatory reporting of poisonings, and by carrying out public education campaigns about pesticide hazards.
Perhaps most important of all, governments can help wean their citizens from pesticide dependency by making a national commitment to sustainable development. Such a commitment would include elimination any subsidies of agricultural chemicals, promoting non-chemical methods of pest control, and fostering the development of sustainable agricultural systems.