EMERGING ISSUE BRIEF Pesticides WHY IS IT AN EMERGING ISSUE? According to a resent article from Inter Press Service News Agency “Pollution, not disease, is the biggest killer in the world, taking the lives of more than 8.4 million people each year, a new analysis shows. That’s almost three times the deaths caused by malaria and fourteen times those caused by HIV/AIDs. However, pollution receives a fraction of the interest from the global community” (1). PESTICIDES Pesticides are responsible for millions of human poisonings and hundreds of thousands deaths each year. By Erik Jørs One of the major polluters is pesticides responsible for millions of human poisonings and hundreds of thousands deaths each year. More than 95% of them take place in lowand middle-income countries which only use 40% of the global production of pesticides. Regulations are lacking, toxic pesticides are easily available and kept unlocked at home. This makes them an easy suicide method and intoxications due to accidents and unsafe handling are very common. WHAT ARE PESTICIDES? Pesticides are poisons meant to kill different kinds of pests and are used by farmers to protect their crops and harvest. Erik Jørs Pesticides are also used in private homes and public health Occupational Health Physician, MIH, Clinic of Occupational and Environmental Medicine, OUH programs to control the spread of vector borne diseases like Layout: designtogo.dk August 2014 malaria, dengue, yellow fever and others. !1 EMERGING ISSUE BRIEF Pesticides Approximately 2.4 billion kg of pesticides were used worldwide in 2007, primarily in agriculture. China is now the country that both uses and produces the largest amounts of pesticides (2). The use of pesticides is a double-edged sword as it has improved agricultural yields and prevented many deaths through minimizing starvation and vector borne diseases, but at the same time it is responsible for TONS OF PESTICIDES IMPORTED TO BOLIVIA 2004-10 (SOURCE: SENASAG 2012) The following figure of pesticide imports during the last decade in Bolivia reflects the boom in pesticide use in most low- and middle-income countries as they boost their agriculture to become self-sustaining and increase exports of agricultural products. millions of people being poisoned each year (2). In some low-income countries, 1/3 of the used pesticides come through illegal import and sale. Stockpiles of obsolete pesticides create a danger for severe human poisonings and environmental pollution (2). CLASSIFICATION OF PESTICIDES Pesticides are classified according to their toxicity, chemical class or target organism. WHO classifies pesticides as belonging to toxic class Ia, Ib, II, III, U or O, where Ia is the most toxic class and U is unlikely to cause any harm. The common chemical classes are organophosphates, organochlorates, carbamates and pyrethroids. The organophosphates and carbamates are acute toxic pesticides, while organochlorates are environmental persistent and travel long distances while accumulating from plants, to herbivores and to carnivores. This is why DDT (an organochlorate) has been found in breast milk among lactating women in Greenland, even though DDT has never been used there. Pyrethroids are not that toxic but might still present problems for health and environment. Finally, the pesticides can be subdivided into insecticides, fungicides, August 2014 !2 EMERGING ISSUE BRIEF Pesticides herbicides, rodenticides and bactericides according to their target organism. HUMAN POISONINGS In 1990, WHO estimated that there at the world level were about 3.000.000 serious intoxications by pesticides per year of which 300.000-400.000 were deadly (3). These are minimum figures due to the boom in pesticide consumption in the last decade in low- and middle-income countries, but good estimates are difficult to obtain due to a lack of reliable registers in low-income countries (2,4,5). The serious acute poisonings are often self-inflicted. For example, in South India self-poisoning with pesticides is responsible for more than 50% of the deaths among 10-19 year old young women (2,5). Suicide attempts are also the main reason behind the comparably few pesticide poisonings in the high-income countries (2). The main reason for the many intentional poisonings by pesticides is the easy availability. Pesticides are often kept unlocked and can be purchased by everyone, including minors in shops or on marketplaces (6). Efficient regulations of imports and sale of pesticides are lacking in most low-income countries making ingestion of pesticides a widely used suicidal method (6). Top: Sale of toxic Class I and II pesticides in Bolivia Bottom: In La Paz you can buy banned pesticides such as e.g. methylparathione. Occupational pesticide poisonings are seen among pesticide factory workers, farmers handling pesticides or entering a newly sprayed field and spray men in public health vector programs. Important reasons behind the many occupational poisonings are the use of very toxic pesticides, banned in most high-income countries, a lack of personal protective equipment and hygienic practices when mixing or spraying pesticides (5,7). These shortcomings are due to poverty and insufficient knowledge of pesticide toxicity and proper handling in low-income countries (5,7). August 2014 !3 EMERGING ISSUE BRIEF Pesticides Accidental poisonings happen when consumers are eating contaminated food, children are mistakenly ingesting pesticides or people are using pesticides as medicine for curing skin infections. PESTICIDES SYMPTOMS AND EFFECTS • Millions of people are poisoned each year by pesticides especially in low and middle income countries. Pesticides enter the body through skin contamination, • In some areas pesticide poisoning is the leading cause of dead in younger age classes outnumbering traditional diseases. carbamates are inhibitors of the cholinesterase enzymes • Severe acute poisonings are due to self harm and accidents, while the most numerous but less severe are occupational poisonings in farming. muscarinic and nicotinic receptors producing symptoms like • Easy access, little knowledge on pesticide handling and protection, lack of control with exports, imports and sale of pesticides are important reasons for poisonings. Other pesticides cause acute pulmonary problems, • To prevent poisonings enforcement of laws and regulations on pesticides; education and awareness rising among users and consumers, and less use of toxic pesticides is needed. • The responsibility to prevent human intoxications and environmental pollution must be taken on by the pesticide industry, the UN and local governments. respiration of droplets and by ingestion. Most pesticides are nerve toxins and the widely used organophosphates and leading to accumulation of acetylcholine in the nerves synaptic cleft (8). This causes excessive stimulation of headache, dizziness, bradycardia, vomiting, diarrhea, dyspnea, ataxia, paralysis and in worst case death (8). bleeding, fever and skin irritation, the latter being very common (8). The acute symptoms of intoxication are rather non-specific and can cause problems diagnosing and treating unless the patient report about resent pesticide exposure. Long-term exposure to pesticides might cause chronic health problems such as neurotoxic, reprotoxic, fetotoxic and carcinogenic effects among others (9). PREVENTION Eliminating or lowering exposure to pesticides is the best way to prevent pesticide poisonings. Banning the use of the most toxic pesticides has proven effective to lower the number of suicides. (5,6) Safe use concepts with a personal protective equipment and improved hygiene are promoted as preventive measures to reduce the numerous occupational poisonings. This has a positive effect, although personal protective equipment might be too expensive for small scale farmers and too hot to use in tropical conditions (10). A broader concept of farmers education is done through Farmers Fields Schools, where Integrated Pest August 2014 !4 EMERGING ISSUE BRIEF Pesticides Management with minimum pesticide use and ecological alternatives have been shown to be able to reduce pesticide use, improve yields, and lower the number of poisonings (10). International treaties are elaborated and promoted by UN organizations to restrict export and sale of the most toxic and persistent pesticides. Many countries have signed them but too often they are not implemented. Local efforts with improved control of imports and sale must be implemented to a much larger degree. CONCLUSION Pesticide use is increasing and pesticides poisonings are now a major and increasing public health issue in many low- and middleincome countries worldwide affecting millions of people. Efforts to band the use of the most toxic pesticides, to teach users about personal protection, hygiene and safe storage as well as control with Farmers teaching farmers on Integrated Pest Management on farmers field schools. the marked must be strengthened to prevent acute and chronic poisonings and environmental disasters. The pesticide industry, local governments and the UN play a major role in implementation of these preventive measures. ! FOR MORE INFORMATION See Fact Sheets 1-5 on http://icoeph.com/materialsicoeph.html and videos on http:// www.youtube.com/results?search_query=Plagbol ! August 2014 !5 EMERGING ISSUE BRIEF Pesticides REFERENCES 1. http://www.ipsnews.net/2014/06/in-developing-world-pollution-killsmore-than-disease/ 2. http://www.pan-germany.org/download/Vergift_EN-201112-web.pdf 3. Jeyaratnam J. Acute pesticide poisoning: a major global health problem. World Health Stat Q 1990;43:139–44. 4. Gunnell C, Eddleston M. Suicide by intentional ingestion of pesticides: a continuing tragedy in developing countries. Int Journ Epidem 2003; 32:902-9. 5. Konradsen F. Acute pesticide poisoning - a global public health problem. Dan Med Bull 2007;54:58–9. 6. Eddleston M, Karalliedde L, Buckley N, Fernando R, Hutchinson G, Isbister G, et al. Pesticide poisoning in the developing world—a minimum pesticides list. The Lancet. 2002;360 7. Jørs E, Morant RC, Concarco GC, Huici O, Lander F, et al. Occupational pesticide poisonings among farmers in Bolivia: a cross-sectional study. Environ Health 2006; 5:10. 8. Thundiyil JG, Stober J, Besbelli B, Pronczuk J: Acute pesticide poisoning: a proposed classification tool. http://www.who.int/bulletin/volumes/86/3/07-041814/en/ 9. Mostafalou S, Abdollahi M. Pesticides and human chronic diseases: evidences, mechanisms, and perspectives. Toxicol Appl Pharmacol. 2013 Apr 15;268(2):157-77. 10. Van den Berg H., Jiggins, J: Investing in Farmers—The Impacts of Farmer Field Schools in Relation to Integrated Pest Management. World Dev 2007, 35:663-686.s Farmer mixing and spraying pesticides with his simple equipment August 2014 !6