Pesticide Residues in Coastal Tropical Ecosystems: Distribution, fate and effects - Chapter 6 ppsx

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Pesticide Residues in Coastal Tropical Ecosystems: Distribution, fate and effects - Chapter 6 ppsx

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Pesticides in Bangladesh 137Chapter 6 Pesticides in Bangladesh M. A. Matin INTRODUCTION Bangladesh is a south Asian country of 144,000 km 2 with 120 million inhabitants and a population growth rate of 2.2 percent per annum. Topographically it is a vast riverine delta, situated at the apex of the Bay of Bengal with a coastal plain of >3,400 km 2 and a coastline of 710 km (Matin, 1995). Bangladesh’s economy is agriculture-based with 10 M ha under cultivation. Arable land per capita (<0.13 ha) is the world’s lowest with a cropping intensity of 159 percent (i.e. land produces 1.59 crops per year), equivalent to >15 M ha cultivated. Agriculture contributes 35 percent to GDP and is growing at an annual rate of 1.9 percent. Obviously fallow land that can be brought under cultivation is minimal in Bangladesh (less than 2 percent), and that small amount is in jeopardy due to pressure from population growth. Rice Oryza sativa L. (Gramineae) is the principal food crop in Bangladesh as it is in other South and Southeast Asian countries (Abdullah et al., 1997). Rice accounts for about 75 percent of the total cropped area, with about 4 M ha of HYV and about 6.7 M ha of local varieties. The country is almost self-sufficient in production of cereals but has a shortfall in many other food crops. Priority at the state level is given to enhancing food production, especially of cereals and pulses (seed-bearing leguminous crops, e.g. beans, peas, lentils), by utilizing all available means including HYV of rice and intensive fanning practices like irrigation, improved seed, chemical fertilizer, and pesticide application. These agricultural practices have had a positive impact on farm productivity. Bangladesh’s food grain production rose to 19.5 M T in 1993 compared with 9.7 M T in 1967 (Rahman et al., 1995). The country is striving for further boosts in agricultural production based on improved manage- ment of the entire agricultural sector. With respect to environmental management and agrochemical control practices and policies in Bangladesh, the current status is disappointing with inadequate and ineffective legislation and enforcement mechanisms. There is a lack of coordination among the various agencies involved in the protection of the environment; however, several national and international agencies have conducted evaluations and put forward recommendations to the government for improvement © 2003 Milton D. Taylor, Stephen J. Klaine, Fernando P. Carvalho, Damia Barcelo and Jan Everaarts 138 M. A. Matin (Coastal Environment Management, 1985; Environmental profile: Bangladesh, 1989; Environment Strategy Review, 1991; National Environment Management Plan, 1991). PESTICIDE REGULATION History of early pesticide legislation Synthetic pesticides, which play an essential role as crop protection agents in modern agricultural systems, began to be used in Bangladesh (then, East Pakistan) in the early 1950s. Marketing of commercial pesticides, mainly OC and OP insecticides, was administered through government agencies and departments. Under the ‘Pesticide Management Rules of Pakistan’ crop protection chemicals were distrib- uted free of cost (fully subsidized), with spraying services and equipment, during the years 1950 through 1971. The Pesticide Control System in Pakistan charged the Agriculture Extension Department with responsibility for pesticide registration and issuing licences. Guidelines for registration and the requisite enforcement mechanisms were not well developed. Current pesticide regulations Bangladesh was founded in 1971 when East Pakistan split away from Pakistan. The Pesticide Ordinance, 1971, of Bangladesh was its first law regulating uses of pesticides (Government of the People’s Republic of Bangladesh, Ministry of Law and Justice, 1984). In its original form the ordinance is a virtual copy of the old Pakistan Pesticide Rules. The Pesticide Ordinance was modified at various times through 1984 to accommodate new pesticides. Subsequently the Pesticide Rules, 1985, was enacted and published in the Bangladesh Gazette-Extraordinary on 16 November 1985, in exercise of powers conferred under section 29 of the Pesticide Ordinance, 1971 (Bangladesh Gazette, 1985). These laws form the legal framework for regulating pesticide uses and associated affairs in Bangladesh. Under the provisions of the Pesticide Ordinance, 1971 and the Pesticide Rules, 1985, a technical advisory committee advises the government on technical matters arising out of the administration of these laws and performs any other functions assigned to it by law. The committee consists of a chairman and a number of members including government officers and representatives of the pesticide industry. The Pesticide Rules Director, in the Plant Protection wing of the Department of Agriculture Extension, or any person authorized by him in writing, constitutes the Pesticide Registration Authority, and also functions as the Pesticide Licensing Authority. An analytical laboratory, still poorly organized and staffed, is also located in the Plant Protection wing of the Department of Agriculture Extension and provides technical services for testing commercial formulations and technical pesticide products. Field tests and efficiency trials may be required in certain cases. © 2003 Milton D. Taylor, Stephen J. Klaine, Fernando P. Carvalho, Damia Barcelo and Jan Everaarts Pesticides in Bangladesh 139 Government subsidization, provided during the East Pakistan period, continued during the early years of the Bangladesh government. Changing circumstances and economic considerations led the Bangladesh government to withdraw subsidies beginning in 1974, and ending them in 1979. At that time pesticide marketing was turned over to the private sector. As a consequence of the subsidy withdrawal, there was a sharp decline in consumption of pesticides. However, pesticide uses continued to be controlled by the government. Then in the early 1980s, agricultural use of pesticides gradually increased. Regulatory provisions describe pesticide registration licensing formalities, although how closely the regulatory mandate is adhered to is a matter of debate. Regulatory provisions are clearly inadequate and need amendment in the areas of use, labeling, and residues. The system of regulation places emphasis on control mechanisms, which are regrettably very poorly enforced. Ideally to ensure safe and effective use of pesticides, use application and application instructions should be evaluated by an independent scientific panel. They should consider data collected by the manufactures’ own research laboratories and other available data concerning toxicity, persistence behavior, and the sensitivity of analytical techniques with respect to formulated products and residues. Bangladesh’s regulatory mechanisms are inadequate in this area. Additionally some control must be exercised over residue levels permitted on foodstuffs. Because it is impossible to test all farm produce, this approach requires establishment of regulations setting residue limits. If exceeded in marketed foods, legal action can be taken against the offending farmer and the condemned produce destroyed. Such regulations are meaningless unless the government employs trustworthy inspectors and analysts with an adequate laboratory infrastructure. Neither the present regulatory framework nor the enforce- ment mechanisms are currently exercised. This situation must improve to ensure safe use of crop protection chemicals. Under the regulatory provisions, the registration of a pesticide remains valid for a period of three years (until 30 June of the third year following the year of registration). However, the government may cancel the registration following a hearing if it believes the registration was secured fraudulently; the pesticide is ineffective; or the pesticide is hazardous to vegetation (other than weeds), humans, or animal life. A license may be issued by the licensing authority to any person or business intending to import, manufacture, formulate, repack, sell, offer for sale, hold in stock for sale, engage in a pest control operation on a commercial basis, or advertise any brand of registered pesticide. A license, unless suspended or canceled, remains valid for a period of two years from the date of issue and, on payment of such fees as may be prescribed, may be renewed for a like period. Regulations regarding adulteration of pesticides are provided in the legal mandate. Any pesticide found to be adulterated; incorrectly or misleadingly tagged, labeled, or named; or its sale contravenes any provision of the Rules or Ordinance may be prohibited from further importation by publication of a notice to that effect in the official Gazette (Bangladesh Gazette, 1985). © 2003 Milton D. Taylor, Stephen J. Klaine, Fernando P. Carvalho, Damia Barcelo and Jan Everaarts 140 M. A. Matin PAST AND CURRENT PESTICIDE USAGE PATTERNS Until recently, rice accounted for more than 80 percent of the quantity of pesticides consumed in Bangladesh. Tea, sugarcane, and potato were next in importance, but with limited use. The use of pesticides has now been extended to vegetables, oilseeds, fruits, tobacco, and other crops. Synthetic pesticides were distributed free of cost along with spraying services and equipment by the Agriculture Department during the l950s and 1960s. Figure 6.1 shows pesticide consumption for granular and conventional products since 1972 and 1973. With the lifting of subsidies beginning in 1974 and ending in 1979, there was a sharp decline in the consumption of pesticides. Subsequently use of pesticides increased gradually. During subsidies the consumption of liquid and other conventional products were three times greater than granular products. Withdrawal of the subsidy resulted in reduced consumption of liquid products and higher usage of granular formulations. High consumption of liquid pesticide formulations in the early years of plant protection activities was primarily because there was free distribution of products, lending of spray equipment, and sharing of responsibility for application by the Plant Protection wing of the Department of Agriculture Extension. During epidemics of specific pests, e.g. the rice ear- cutting caterpillar Mythimna separata Walk. (Lepidoptera: Noctuidae) or rice hispa Dicladispa armigera Olivier (Coleoptera: Chrysomelidae), government applicators conducted aerial spraying. With the introduction of HYV, use of pesticides increased Figure 6.1 Pesticide consumption in Bangladesh from 1973–95 0 2 4 6 8 10 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 Year Tonnes (× 1,000) Conventional Granular © 2003 Milton D. Taylor, Stephen J. Klaine, Fernando P. Carvalho, Damia Barcelo and Jan Everaarts Pesticides in Bangladesh 141 beginning in the early 1980s. The ‘Grow More Food’ campaign, beginning in the early 1980s, also promoted increased consumption of pesticides. Currently there is increased use of granular insecticides. The reasons include ensured efficacy, a longer protection period, the scarcity of workable spray equip- ment, and ‘ready to use’ formulations. About 6,000 T of granular products were used in 1994 compared with 1,220 T liquid (EC or emulsifiable concentrate) formulations and less than 100 T soluble (SP) or wettable powder (WP) formulations. A review of the consumption of insecticides, herbicides, and fungicides finds that Bangladesh is predominantly an insecticide market (Figure 6.2). However, fungicides and herbicides are steadily gaining market share. By 1994, 500 T of fungicides and herbicides were used annually in Bangladesh. Fungicides are primarily used for cash crops such as potato, but fungicide use has also expanded in rice production. During 1990 to 1995, the average increase in consumption of 1 percent, 22 percent and 3 percent for insecticides, fungicides, and herbicides, respectively, was mostly due to increased awareness of losses from diseases in field crops. From Figure 6.2, it is evident that OP and carbamate pesticides constitute about 90 percent of the market, while OCs and other types of crop protection chemicals make up the remainder. Pesticides are used on <10 percent of cropped land with approximately 100 gm a.i. being applied per ha. Pesticides are considered crucial for improving agricultural productivity and to prevent crop loss both pre- and post-harvest. The annual consumption of formulated pesticides for agriculture in Bangladesh is gradually increasing (Matin, 1995; Rahman et al., 1995). Consumption has risen from 2,510 T in 1982 to 1983 and 5,150 T in 1988 to 1989 (Rahman et al., 1995) to 7,800 T in 1993 and just over 8,000 T in 1995 (Matin, 1995). The value of these agrochemicals was 1 billion taka (40 taka = US$1) or US$25 M in 1993. Insecticides Fungicides Herbicides Others Others Pyrethroids Carbamates OPs OCs Figure 6.2 Distribution of pesticides classified by function and insecticides by chemical group © 2003 Milton D. Taylor, Stephen J. Klaine, Fernando P. Carvalho, Damia Barcelo and Jan Everaarts 142 M. A. Matin Crop protection chemicals have had a positive impact on the increased production of rice (Rahman et al., 1995). However, consumption of pesticides is still low compared to other countries in the region. The real problem with pesticide use may be weak control mechanisms, which may result in widespread misuse and excess application. Thus, there is considerable concern about the misuse of pesticides in Bangladesh. Rice paddies, especially those planted with HYV, require strict pest management through the application of pesticides. HYV rice is vulnerable to various insect pests (Table 6.1) including rice hispa, stem borers Scirpophaga sp. and Chilo sp. (Lepidoptera: Pyralidae), plant hoppers Pyrilla perilla perpusilla Wlk. (Homoptera: Fulgoridae) and leafhoppers (Hemiptera: Cicadellidae), the rice ear- cutting caterpillar, rice case worm Nymphula depuunctalis Guen. (Lepidoptera: Pyralidae), and the rice army worm Spodoptera mauritia Boisd. (Lepidoptera: Noctuidae) among others. Consequently with such a broad array of potential insect pests to attack the HYV rice, pesticides are required for adequate control (Howlader and Matin, 1988). Per hectare consumption of crop protectants (as formulated products) has gradually increased from 0.35 kg ha –1 in 1984 to 0.60 kg ha –1 in 1989 and an estimated 0.8 kg ha –1 in 1995. Generally insecticide is applied once during the growing season (primarily during the winter season from December to March), but repeated applications may be required to control pest outbreaks and to increase the growing season of the crop. The population of Bangladesh is estimated to reach 223 million by 2030 with little additional land available to boost food production. Presently over 10 M ha of agricultural land are used for rice cultivation, mostly by small farmers. Rice production, which was 9.7 M T in 1967, increased to about 20 M T in 1994 through intensive farming techniques and the use of HYV rice (Matin, 1995). Table 6.2 lists the active ingredients of pesticides registered for use in Bangladesh. Of 39 listed insecticides, 24 are labeled for rice. Table 6.3 sets forth the pesticides that are used for rice cultivation in Bangladesh and their application rates. It is apparent from the table that most rice pesticides, none of which are OCs, are insecticides with only a few being fungicides. While not registered, some persistent OCs are illegally applied because of weak regulatory controls and inadequate surveillance programs. Heptachlor, however, is registered in Bangladesh for other agricultural purposes (sugarcane cultivation). OPs constitute the greater part of insecticides (60 percent); carbamates (28 percent); and pyrethroids, OCs, and others (12 percent). Of the commonly used rice insecticides, diazinon, carbofuran, malathion, chlorpyrifos, fenthion, fenitrothion, carbaryl, dimethoate, dichlorvos, and fenvelarate find wider application in rice field ecosystems. Herbicides are not generally used for the rice paddy field although they are used for other crops such as tea. Of the 21 fungicides and 10 herbicides registered for use in Bangladesh only three fungicides find application in the rice paddy field. Geographically Bangladesh is divided into five regions, Dhaka, Chittagong, Rajshahi, Khulna, and Barisal. Pesticide consumption for each region from four time periods is shown in Table 6.4. For the country, per ha consumption of pesticides gradually increased from 0.35 kg ha –1 in 1984 to 0.60 kg ha –1 in 1989 and was estimated as 0.80 kg ha –1 in 1995. Annual consumption (kg ha –1 yr –1 ) of pesticides © 2003 Milton D. Taylor, Stephen J. Klaine, Fernando P. Carvalho, Damia Barcelo and Jan Everaarts Pesticides in Bangladesh 143 was highest in Chittagong (having a higher population density and more extensive farming practices) and lowest in Dhaka (land much more devoted to industrial enterprises). Because there is little additional land to boost food production for an expanding population, multiple cropping or intensive farming practices, involving HYV use, are necessary, thus increasing pesticide consumption from multiple applications of crop protection chemicals. Table 6.1 Principal pests of important crops in Bangladesh Name of the crop Common name of the pest Scientific name Rice Rice hispa Dicladispa armigera Olivier Gold-fringed borer Chilo auricilius Dudgeon White rice borer Tryporyza innotata Walker Pink borer Seasamia inferens Walker Stem borer Chilo partellus Swinhoe Yellow stem borer Scirpophaga incertulas Walker Pale headed stripped rice borer Chilo suppresalis Walker Rice case worm Nymphula depuunctalis Guenée Rice ear-cutting caterpillar Mythimna separata Walker Rice army worm Spodoptera mauritia Boisduval Wheat Termite Microtermes anandi Holmgr. Wheat aphid Rhopalosiphumn rufiabdominali Sasaki Tea Red spider mite Oligonychus coffeae Nietner Shoot-hole borer Xyleborus sp. Trank borer Heterobostrychus aequalis Waterhouse Tea mosquito bug Helopeltis sp. Jute Jute hairy caterpillar Diacrsia obliqua Walker Jute semi-looper Anomis sabulifera Guenée Jute stem weevil Apion corchori Marshall Sugar cane Top shoot borer Scirpophaga monostigmata Zeller Stem borer Scirpophaga exerptralis Walker Sugar cane top shoot borer Scirpophaga auriflua Zeller Sugar cane stem borer Chilo tumidicostalis Hampson Leafhopper Pyrilla perilla perpusilla Walker Pulses Pod weevil Bruchus pisorum L. Pod beetle Pachymerus chinensis L. Leaf caterpillar Chaetochema cohcicpennis Bally Gram weevil Alcides colloris P. Azuki bean weevil Callosobruchus chinensis L. Pulse beetle Gonocephalum elongatum Fabricius Stored grains Rice weevil Sitophilus oryzae L. (rice and wheat) Angoumois grain moth Sitotroga cerealella Olivier Red flour beetle Tribolium castaneum Herbst Grain weevil Sitophilus granarius L. Depressed flour beetle Palorus subdepressus Wollaston © 2003 Milton D. Taylor, Stephen J. Klaine, Fernando P. Carvalho, Damia Barcelo and Jan Everaarts 144 M. A. Matin PESTICIDE RESIDUES IN BIOTA AND ABIOTIC MATRICES Pesticide residues originate from application of the formulated a.i.(s) to crop fields and may be transported offsite through spray drift and runoff aided by rain, floods, tidal surge etc. (Hassall, 1990). Consequently contamination of canals, ponds, Table 6.2 List of registered pesticides (a.i.) in Bangladesh Acaricides Bromopropylate Sulphur Dicofol Propargite Ethion Tetradifon Fenbutatin oxide (Hexakis) Fungicides Chinomethionate (Oxythioquinox) Triadimefon Carbendazim Triadimenol Carboxin + Thiram Thiophanate-methyl Edifenphos Thiabendazole Copper oxychloride Aluminum phosphide Iprodione Methyl bromide Mancozeb Cufraneb Methacrifos Propineb Metiram Propiconazole Primiphos-methyl Metalaxyl Tridemorph Rodenticides Flocoumafen Coumatetralyl Brodifacoum Zinc phosphide Bromadiolone Herbicides Glyphosate Dazomet Terbuthylazine Diuron Glufosinate-ammonium Paraquat 2,4-D Propanil Dalapon Na Oxadiazon Insecticides BPMC (fenobucarb) Fenitrothion Carbaryl Fenvalerate Carbofuran Esfenvalerate Carbosulfan Formothion Cartap Isazofos Chlordane Heptachlor Chlorpyrifos Malathion Chlorpyrifos methyl Monocrotophos Cypermethrin Methamidophos Cyfluthrin Phenthoate Fenpropathrin Pirimicarb Deltamethrin Quinalphos Diazinon Tetrachlorvinphos Dichlorvos Trichlorfon Dimethoate Isoprocarb Endosulfan Methyl demeton Etofenprox Phosalone Fenthion Phosphamidon © 2003 Milton D. Taylor, Stephen J. Klaine, Fernando P. Carvalho, Damia Barcelo and Jan Everaarts Pesticides in Bangladesh 145 rivers, and other waterways with residues of the parent compounds or their degrada- tion products is possible (Rahman, 1995). Furthermore, food harvested from the application sites and elsewhere may be contaminated with residues (Rahman, 1995). Fish cultured or living in the fields or nearby and fish in downstream waterways can be affected by toxic residues (Abdullah et al., 1997). Fish are the major non- target species adversely affected by application of hazardous pesticides (Abdullah et al., 1997). Populations of both flora and fauna have been reported to be Table 6.3 Pesticides recommended (registered) for rice fields in Bangladesh with application rates a Common name Concentration/formulation b Rate (ha –1 ) Insecticides BPMC (fenobucarb) 50 EC 1.0 L Carbaryl 85 WP 1.4 kg Carbofuran 3 G 16.7 kg Carbosulfan 20 EC 1.5 L Cartap 10 G 16.8 kg Chlorpyrifos 20 EC 1 L Diazinon 10 G 16.8 kg 60 EC 1.5 L 14 G 13.5 kg Dichlorvos 100 EC 560 ml 50 EC 1 L Dimethoate 40 EC 1.2 L Etofenprox 10 EC 0.5 L Fenthion 50 EC 1.5 L Fenitrothion 50 EC 1.12 L Fenvalarate 20 EC 250 ml Isazofos 3 G 16.8 kg Formothion 25 EC 1.12 L Malathion 57 EC 1.12 L Monocrotophos 40 WSC 1.5 L Isoprocarb 75 WP 1.5 L Phosalone 35 EC 1.0 L Phosphamidon 100 SL 0.5 L Quinalphos 5 G 16.3 kg 25 EC 1.5 L Tetrachlorvinphos 75 WP 1.12 L Primiphos methyl 50 EC 1.0 L Fungicides Edifenphos 50 EC 840 ml Pyroquilon 50 WP 600 g Thiophanate methyl 70 WP 2.4 kg Notes: a Adapted from Plant Protection Wing, Department of Agriculture Extension, Khamar Bari, Farmgate, Dhaka, Bangladesh. b Formulation abbreviations are as follows: G, granular; WSC, water soluble concentrate; SL, slurry. © 2003 Milton D. Taylor, Stephen J. Klaine, Fernando P. Carvalho, Damia Barcelo and Jan Everaarts 146 M. A. Matin experiencing significant declines due to application of pesticides in Bangladesh and elsewhere (Hassall, 1990). Many other undesirable side-effects may appear in the aftermath of repeated pesticide application (Hassall, 1990; Rahman, 1995). Organochlorine and pyrethroid insecticides, in general, may cause damage to fish and other non target species (Hassall, 1990). In Bangladesh a complete risk assessment of the use of pesticides, especially in the rice paddy ecosystem, has yet to be made. Scattered published reports coupled with some preliminary findings (since 1992) by the Institute of Food and Radiation Biology of the Bangladesh Atomic Energy Commission suggest misuses of crop protection chemicals in Bangladesh. This is due to a lack of or inadequate enforcement of regulatory measures. Unregistered compounds find application in agriculture due to poor enforcement of the relevant law by authorities (Matin et al., 1995). Unlawful use of DDT to treat pest infestations in dried fish has been detected and residue levels were found to be high (IAEA, 1995; Matin et al., 1995). In subsequent studies using dried fish treated with 14 C- DDT, Matin et al. (1996) found that, luckily for consumers, most of the applied DDT remains on the surface of the sun-dried fish and also that most of the residue could be eliminated during pre-cooking processing using traditional household preparation techniques (Figure 6.3). Table 6.4 shows the range of pesticide residues (including toxic metabolites) measured in food and environmental samples from Bangladesh. Although OC insecticides are not registered, residues are found in different components of the 0 10 20 30 40 50 0 15 30 45 60 75 90 105 120 135 150 165 180 Storage time (d) Elimination of DDT (as % of applied activit y Figure 6.3 Removal of DDT by water washing of dried fish treated with 14 C-DDT © 2003 Milton D. Taylor, Stephen J. Klaine, Fernando P. Carvalho, Damia Barcelo and Jan Everaarts [...]... for pesticides may lead to various effects in plant and animal species under cultivation and in the wild The aquatic environment including marine coastal and estuarine waters support the growth of fish and other biota that may be affected by pesticide residues transported into both inland waterways and coastal waters through flooding, rainfall, and runoff Fish migrate to crop fields during flooding and. .. 1993 p,p´-DDT o,p´-DDT p,p´-DDE Lindane Water (paddy 1994–95 Dieldrin field, irrigation p,p´-DDT canal, adjoining p,p´-DDE river and ponds) p,p´-DDD o,p´-DDT Lindane Heptachlor Vegetables 1993 p,p´-DDT (leafy vegetables), p,p´-DDE cabbage, beans, o,p´-DDT brinjal, peas Fruits 1993 o,p´-DDT p,p´-DDT p,p´-DDE Pulses 1993 p,p´-DDT o,p´-DDT p,p´-DDE 4.12–2 76. 29 mg kg–1 0.45–1.80 mg kg–1 2.19–7 .62 mg kg–1... plants (submerged and emergent portions), fish, and grain samples was measured (Islam, 19 96) Extractable and bound activity in soil was determined using LSC and BO The highest residues were found in soil on day 16 after pesticide application In catfish, residues were again higher in the viscera (1 .66 µg g–1) than that in muscle but in rice the highest residue concentrations were found in the submerged... farming problems, especially pests and diseases IPM implementation for rice and vegetable crops in Asia has resulted in dramatic drops in the use of insecticides and fungicides in recent years, lowering use by more than 35 percent in the Philippines, 49 percent in Indonesia, 15 percent in China, 14 percent in Vietnam, and 29 percent in India (Ramaswamy, 1995) Labor costs have likewise dropped in all... M.S and Rahman, M 1995 DDT residues in dried fish of Bangladesh Nucl Sci Appl 4(1) :61 Matin, M.A., Khatoon, J., Rahman, M and Mian, A.J 19 96 Influence of pre-cooking processing and storage on reduction of DDT residues from dried fish treated with 14CDDT Nucl Sci Appl (1–2):17– 26 Matin, M.A, Amin, M.R., Rahman, S., Khatoon, J., Malek, M.A., Rahman, M and Mian, A.J 1997a Studies on pesticide residues in. .. by IPM Master Trainers (who have received in- depth IPM training both in Bangladesh and abroad) from the Department of Agriculture Extension in Dhaka and the FAO Inter-country IPM Project So far, 91 farmers’ IPM field schools have been established in 74 Thanas in 39 districts Using the field schools as the training ground, senior extension officers in the eight regions and from all the 64 districts were... collaboration, and expert guidance in devising practical steps for the control of pesticides They are assisting in maximizing pesticides’ beneficial role while minimizing risks associated with undesirable levels of residues in food chains and untoward effects on non-target organisms in the environment (Ambrush, 1997) Two new and vital control systems are expected to be implemented as far as possible in Bangladesh... levels However, no report of residues from the predominantly used pesticides (OPs and carbamates) was found despite detection of persistent OCs in many samples From Table 6. 5, among the DDT family, p,p´DDT, p,p´-DDE, and p,p´-DDD were most often observed in various food and environmental samples and, in some cases, lindane in sediment samples, and endosulfan and dieldrin in fish samples were detected... DDT, lindane, aldrin, dieldrin, endrin, heptachlor, © 2003 Milton D Taylor, Stephen J Klaine, Fernando P Carvalho, Damia Barcelo and Jan Everaarts Pesticides in Bangladesh 149 Table 6. 5 Pesticide residues in food and the environment in Bangladesh Location Sample/ components Year Compounds detected Concentrations (range/mean value) Tangail/Sirajganj FAP embankment Rice-field fish 1992 p,p´-DDT p,p´-DDE... p,p´-DDD Endosulfan p,p´-DDT o,p´-DDT p,p´-DDE 1.10–24.9 mg kg–1 0.75–12.0 mg kg–1 0.05 mg kg–1 Trace–281.88 mg kg–1 7. 86 142 .66 mg kg–1 1. 76 38.00 mg kg–1 9 .60 –101.12 mg kg–1 River, ponds, Fish major rice growing fields rice field runoff Dhaka (Narshindi) Rice Chittagong Mymensingh Narsinghdi (paddy field) Major rice growing regions Dhaka (Savar, Manikganj) 1993 1993 p,p´-DDT o,p´-DDT p,p´-DDE p,p´-DDD . consumption for granular and conventional products since 1972 and 1973. With the lifting of subsidies beginning in 1974 and ending in 1979, there was a sharp decline in the consumption of pesticides. Subsequently use. p,p - DDT, p,p´-DDE, and p,p´-DDD were most often observed in various food and environmental samples and, in some cases, lindane in sediment samples, and endo- sulfan and dieldrin in fish samples. Dieldrin 0 .64 mg L –1 growing regions field, irrigation p,p´-DDT 0. 06 19 .60 mg L –1 canal, adjoining p,p´-DDE 0.01–2.51 mg L –1 river and ponds) p,p´-DDD 0.01–0.37 mg L –1 o,p´-DDT 0.01–0. 26 mg

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  • Table of Contents

  • Chapter 6: Pesticides in Bangladesh

    • INTRODUCTION

    • PESTICIDE REGULATION

      • History of early pesticide legislation

      • Current pesticide regulations

      • PAST AND CURRENT PESTICIDE USAGE PATTERNS

      • PESTICIDE RESIDUES IN BIOTA AND ABIOTIC MATRICES

      • ECOTOXICOLOGY OF PESTICIDES

      • DISTRIBUTION AND FATE OF PESTICIDES IN MODEL MICRO-ECOSYSTEMS

      • SUSTAINABLE PEST CONTROL THROUGH IPM

      • APPROACHES FOR PESTICIDE MANAGEMENT

      • REFERENCES

      • Appendix: Listing of all presticides mentioned, identification numbers and activities

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