Vegetable farmers perception of pesticide use practices in Thanh Hoa province, Viet Nam

Hong Duc University Journal of Science, E.5, Vol.10, P (13 - 23), 2019 13 F ac. o f G rad . S tu d ies, M ah id o l U n iv . M . M . (In tern atio n al H o sp itality M an ag em en t) / 1 3 VEGETABLE FARMERS PERCEPTION OF PESTICIDE USE PRACTICES IN THANH HOA PROVINCE, VIETNAM Le Van Cuong, Mai Thanh Luan, Nguyen Thi Mai 1 Received: 12 February 2019/ Accepted: 11 June 2019/ Published: June 2019 ©Hong Duc University (HDU) and Hong Duc University Journal of Science Abstract: Pesticide use practices among smallholder vegetable farmers in Thanh Hoa province were investigated through field surveys, questionnaires, and interviews. This study was carried out to assess the knowledge and perception of vegetable growers regarding the appropriate knowledge on safe handling and proper use of pesticides. The results revealed that farmers’ choices of pesticides was strongly influenced by both authorized pesticide dealers and neighboring farmers. In addition, Over 87% farmers did not read written information on pesticide label before use. Consequently, most farmers applied pesticides in violation of the recommendations: they overused, misused, and abused pesticides for pest control, ignore risks and safety instructions, they did not respect pre-harvest interval and dispose containers unsafely. Improved safety training and provided further information on technical aspects of pesticide use would be a cost-effective solution to raise awareness of vegetable farmers about negative impact of pesticides on population health and the environment. Keywords: Pesticide use, pesticide application, environment, agriculture, Thanh Hoa province. 1. Introduction Pesticides are widely used in agricultural production to control insects, diseases, weeds and other undesirable pests, thus constitute one of the most important inputs in crop production [3], [5], [12]. However, the increased use and misuse of pesticides have negative health effects on farmers, traders and consumers, and threaten the natural environment. Unsafe and indiscriminate use of pesticides is common in tropical agricultural systems of developing countries including Vietnam due to farmers poor knowledge on the hazards of pesticide use, risks of hazardous agrochemicals and ineffective governmental enforcement of pesticides‟ regulations [2], [6]. There are about 80% of Vietnamese farmers using pesticides incorrectly (i.e. violating the „4Rright‟ principles) causing environmental damage and a number of human health effects [11]. Besides, the types of pesticides and the active ingredients (AI) of pesticides of toxic categories II (moderately hazardous), III (slightly hazardous), and U (unlikely to present acute hazard) have increased considerably (7.4-, 5.9- and 9.1-fold, respectively) from 2002 to 2013 in Vietnamese pesticide market [1]. Recently, low-quality pesticides and counterfeit pesticide is also a major problem for farmers, food Le Van Cuong Department of General Administration, Hong Duc University Email: Levancuong@hdu.edu.vn Mai Thanh Luan, Nguyen Thi Mai Faculty of Agriculture, Forestry and Fishery, Hong Duc University Hong Duc University Journal of Science, E.5, Vol.10, P (24 - 31), 2019 14 F ac. o f G rad . S tu d ies, M ah id o l U n iv . M . M . (In tern atio n al H o sp itality M an ag em en t) / 1 4 consumers and the environment. Consequently, more than 7000 cases of pesticides residue poisoning were reported in 2002 in Vietnam [10]. In Thanh Hoa province, where the people living by agriculture account for 85 % of the population, the production areas of vegetable had expanded remarkably to 38762 ha by 2014, leading to a rapidly increase of total quantity of pesticides used for managing insects, weeds and diseases. 110 tone of pesticides with 420 different types of pesticides were applied in field to protect crop production in 2015. It has been shown that more and more local vegetable farmers are now applying pesticides intensively to their crops and relying heavily on the use of pesticides in order to improve vegetable production to meet local market and export market demand. These might pose threats to population health, vegetable consumers, and the environment. Thus, the purpose of this study is to investigate into pesticide knowledge, attitudes related the use of pesticide, safety practice pesticides among vegetable farmers in Thanh Hoa province. The study provided information about pesticide use practices including the types of pesticides used, factors that influence pesticide selection and use, ability to read and understand information written on the label and pesticide safety training. This information will be useful for pesticide policy enforcement and development of more sustainable pesticides use practices by vegetable farmers. 2. Material and methods Selection method of research area: Interviews and surveys were conducted in Thanh Hoa province, which is located in the North Central Coast region of Vietnam, in December 2017. We selected 450 vegetable farmers for interviews from 5 districts which represent 3 specific areas, includes: Thieu Hoa and Thanh Hoa city represent the dental region; Hoang Hoa, Tinh Gia represents the coastal region and Tho Xuan represents the mountainous region. Methods of collecting information: Primary data collection: qualitative and quantitative data were collected from vegetable growers through farm survey by face-to-face interviews with vegetable farmers/sprayers, in-depth interviews managers, group discussions Participatory Rural Appraisal (PRA) and field observations. A questionnaire containing structured closed-ended questions was designed based on relevant published literature. Secondary data were collected from the legislation and the provisions of plant protection in Thanh Hoa province. Data were analysed by Microsoft EXCEL and Statistical Package for Social Sciences (SPSS) software 22.0. 3. Results Pesticide use and safety training: The result of table 1 indicates that vegetable crops area is approximately 38432 ha in 2015 in Thanh Hoa province. Pesticide consumption per year continuously reduced by 110 tons in 2015. Likewise, pesticide use per hectare also decreased by 0.27 kg/ha in 2015. However, the number of cases of pesticide poisoning incidents did not significantly reduce from 2013 to 2015 suggesting the main reason causing pesticide poisoning to farmers and consumers in Thanh Hoa province in 2015 which possibly related to pesticide use practices (Table 1). In addition, 25.11% of vegetable growers reported that they did not received any training or technical support on safe pesticide use. Besides, the safety training frequency for farmers differed significantly among regions. 18.33 % of Hong Duc University Journal of Science, E.5, Vol.10, P (13 - 23), 2019 15 F ac. o f G rad . S tu d ies, M ah id o l U n iv . M . M . (In tern atio n al H o sp itality M an ag em en t) / 1 5 vegetable growers in delta areas (n =180) received frequently pesticide safety training while the percentage of farmers coastal areas and attended frequently pesticide safety training were 5% and 4.44% respectively (table 2). In terms of training content, approximately 50% of respondents participated in pesticide products, which mainly focused on advertising and selling pesticides products, but not pesticide use practice (table 2). Table 1. The 2013-2015 report on Pesticide use in Thanh Hoa Item Unit 2013 2014 2015 1. Annual crop area ha 447102 448928 443680 Rice ha 256300 258600 257000 Vegetable ha 38100 38762 38432 2. Pesticide consumption ton 290 146 110 3. Pesticide use per hectare kg/ha 0,648 0,325 0,247 4. Pesticide poisoning incidents Number of cases 17 14 15 Table 2. Training received by farmers on safe pesticide use in studied locations Unit: (%) percentage of household Variable Delta areas (n=180) Coastal areas (n=180) Inland areas (n=90) Mean (n=450) 1. Safety training frequency Frequently 18,33 5,00 4,44 10,22 Sometimes 80,56 63,33 35,56 64,67 Not yet 1,11 31,67 60,00 25,11 2. Training contents Pesticide products 45,56 51,67 56,67 50,22 Pesticide use 54,44 48,33 43,33 49,78 Pesticide use practices: The list of pesticides used by farmers in surveyed locations is showed in Supplementary Table 1. The data show that insecticides (61.81%) are the most used pesticides, follows by fungicides (30.9%) and herbicides (7.2%) usage. There were no pesticides classified as extremely hazardous (Ia) or highly hazardous (Ib) being applied based on the WHO guidelines to classification of pesticides by hazard (2009). However, 28 out of 55 (50.9 %) of pesticides were unregistered for use on vegetables. Moreover, 17 out of 55 (30.9 %) of pesticides classified as moderately hazardous (II) were widely applied in the vegetable production area (Supplementary Table 1) because they found them very effective. Supplementary Table 2 presents the fact of pesticide use practices of vegetable growers in surveyed locations. 33.78% of vegetable farmers selected pesticides according to neighbour‟s recommendation. Over 60% of farmers were directly influenced by authorized dealer recommendations, while 30.89% followed extension worker‟s recommendation. For pesticide application timing, spraying in the afternoon was the most common (45.33%). 10.44% of farmers sprayed pesticide in early morning while 8.44% of those applied pesticide at any time of the day. Most farmers applied pesticide was based on noticing crop damage Hong Duc University Journal of Science, E.5, Vol.10, P (24 - 31), 2019 16 F ac. o f G rad . S tu d ies, M ah id o l U n iv . M . M . (In tern atio n al H o sp itality M an ag em en t) / 1 6 (43.33%) and neighbour‟s recommendation (45.56%). Few (11.11%) farmers followed extension worker‟s recommendation to apply pesticide at right time in their crop. 80.22% of farmers interviewed in surveyed areas applied pesticide at higher rate (from 1.5 to 2 times) than permitted by the label on the pesticide product. They assumed that applying pesticide at higher dose would achieve greater effectiveness to control pests and diseases in their crop, without considering the effects on their health, vegetable consumers and the environment. For pesticide spraying techniques in the field, the results of Supplementary Table 2 shows that 24.67% of farmers sprayed pesticides with the wind direction to minimize their exposure to toxic pesticide, while 6.22% did not consider wind direction when spraying pesticide. Over 87% of the farmers did not read written information on pesticide label before use, including the direction on how to mix, apply in the field, because they were unable to read and understand the meaning of the label. Few (12.44%) farmers read and understood pesticide labels correctly. Besides, often two or more pesticides were mixed together in the sprayer tank without consideration of pesticide compatibility or effects on workers. Those famers reasoned that mixtures would result in higher effectiveness of pest control and control more than one pest with the same application. According to Ngowi et al. (2007), mixing more than two different types of pesticides possibly causes interactions between fungicides, insecticides and water mineral content, resulting in reduction of pesticide efficacy, the mixture could be less effective to pests, more toxic to sprayers and the environment. For pre-harvest interval (PHI), 51.78% of interviewed vegetable growers still harvested vegetables before the pre-harvest interval written on the label expires due to their economic profit, 7.78 % of respondents did not check the label of pesticide products for pre-harvest interval. For protective measures during spraying, 90.44% of respondents used mask, gloves (11.78%), boots (25.33%), hat (69.11%), and raincoat or safety clothes (7.11%). Farmers’ attitudes toward effect of pesticides on the environment: The most common way of disposing of leftover pesticides were spraying until no pesticide left (91.56%). For disposal empty pesticide containers after use, 48.44% of vegetable growers reported to throw them in the field. Alternatively, 47.78% gathered and kept in safe places. Most farmers (86.89%) cleaned pesticide application equipment after use, including spray tanks, valves, booms, nozzles in the field without concerning about contamination of water by rinse water and the remains of pesticide. 4. Discussion Pesticide use practices and pesticide knowledge among smallholder vegetable farmers in Thanh Hoa province were surveyed. This study indicated that most of vegetable farmers apply pesticides indiscriminately in violation of the recommendations: they still relied heavily on and overused pesticides, moderate hazardous (II) pesticides were still used widely in the vegetable production area, used unregistered pesticides for use on vegetables, ignore risks and safety instructions and did not use protective devices when applying pesticides. These problems can be possibly attributed to farmers‟ lack of pesticide knowledge and pesticide safety training. Similarly, the study of Mengistie et al. (2017) revealed that training on safe pesticide use significantly influences on the knowledge, attitudes, and practices concerning pesticide use of vegetable farmers. Lack of technical pesticide knowledge, the Hong Duc University Journal of Science, E.5, Vol.10, P (13 - 23), 2019 17 F ac. o f G rad . S tu d ies, M ah id o l U n iv . M . M . (In tern atio n al H o sp itality M an ag em en t) / 1 7 absence of extension services and lack of pesticide safety training results in pesticide misuse (abuse and overuse) by farmers. On the other hand, Nguyen et al. (2018) reported that though a high number of vegetable farmers receive training on pesticide use, most of them still violated pesticide recommendations, applied widely moderate hazardous (II) and unregistered pesticides for vegetable production that affect the safety of vegetables for consumption. Our study shows that the choice of pesticides to be used by vegetable growers was strongly influenced by both authorized pesticide dealers and neighboring farmers. This is also common in developing countries including Ethiopia central rift valley [6]. Farmers generally use a higher dosage of pesticides than recommended in their crops because they want to reduce spraying frequency and eliminate pests at once. Excessive pesticides use may lead to high residue levels on plants, which may be toxic to vegetable consumers and the environment [14]. Mengistie et al. (2017) reported that 87% of famers mix two pesticides without considering undesirable interactions between pesticides in mixture which may lead to reducing active ingredient effectiveness or adverse effects to the pests, damaging their health or the environment [6], [7], [13]. Our survey showed that many vegetable farmers did not use protective equipment such as gloves, boots, hat and safety clothes during spraying due to lack of availability and affordability. The use of protective equipment makes farmers feel uncomfortable under local hot and humid climates and cumbersome during working, while some consider it too expensive to access [9], [6]. Most of farmers in surveyed location did not read the pesticide label carefully before applying. Consequently, they did not follow pre-harvested interval written on the pesticide label or consider pre-harvest interval when they applied pesticides. Another reason mentioned for not respecting recommended pre-harvested interval was economic profit in which harvest time was almost determined by vegetable dealers and market demand. The study of Nguyen et al. (2017) also showed that 98% of farmers were aware of recommended pre-harvested interval written on pesticide label, but they did not always follow it. According to Jeyanthi and Kombairaju (2005), the level of pesticide residues still greatly remained on vegetable products before with holding period. 5. Conclusion The study revealed that vegetable farmers in surveyed location including 5 districts (Hoang Hoa, Thieu Hoa, Tinh Gia, Tho Xuan and Thanh Hoa city) in Thanh Hoa province apply pesticides indiscriminately in violation of the recommendations. They often overuse, misuse, abuse pesticides for pest control in their crops without considering potential threats to their health, vegetable consumers and the environment. The farmers‟ choices of pesticides was strongly influenced by both authorized pesticide dealers and neighboring farmers, and most of the farmers did not read written information on pesticide label before use was possibly an important reason for indiscriminate use and improper application of pesticides by vegetable farmers. Providing further information and safety training courses on the economic, scientific, legal and technical aspects of pesticides could be feasible solutions for raising awareness among vegetable growers about potential hazards of pesticides to their health, consumers and the environment. Hong Duc University Journal of Science, E.5, Vol.10, P (24 - 31), 2019 18 F ac. o f G rad . S tu d ies, M ah id o l U n iv . M . M . (In tern atio n al H o sp itality M an ag em en t) / 1 8 Supplementary Table 1. List of pesticides used by farmers in vegetable production in Thanh Hoa province, Vietnam Types of Pesticides Trade name Active ingredients (Ai) Registered for use on Toxic class (by WHO*) Original pesticides In se ct ic id e (6 1 .8 1 % ) Acdinosin 50WP Nitenpyram; Fipronil; Dinotefuran Rice III Synthetic pesticide Amico 10EC Imidacloprid Rice III Synthetic pesticide Anvado 100WP Imidacloprid Rice II Synthetic pesticide Bafurit 5WG Emamectin benzoate Rice, vegetables, tea III Bio-pesticide Bemab 52WG Emamectin benzoate Rice, vegetables II Bio-pesticide Bestox 5EC Alpha_cypermethrin Rice, soybean II Synthetic pesticide Binova 45WP Acetamiprid; Buprofezin Rice II Synthetic pesticide Blugent 75SC Fipronil; Indoxacarb Rice II Synthetic pesticide Calira 555WP Imidacloprid; Acetamiprid; Buprotezin Rice III Synthetic pesticide Checsura 500WP Chlorpyrifos Ethyl; Acetamiprid Rice II Synthetic pesticide Conphai 15 WG Imidacloprid Rice, coffee II Synthetic pesticide Dofaben 100WG Emamectin benzoate Rice, vegetables II Bio-pesticide Dylan 2EC Emamectin benzoate Rice, vegetables, fruits III Synthetic pesticide Ema aici 50WG Emamectin benzoate Rice, vegetables III Bio-pesticide Fm- Tox25EC Alpha cypermethrin Rice, vegetables, coffee II Synthetic pesticide Goldra25 0WG Thlamethoxam; Acetamiprid Rice, sugarcane II Synthetic pesticide Golnitor 50WDG Emamectin benzoate Rice, vegetables, fruits III Bio-pesticide Goltoc 250EC Quinalphos; Fipronil Rice II Synthetic pesticide Hong Duc University Journal of Science, E.5, Vol.10, P (13 - 23), 2019 19 F ac. o f G rad . 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(In tern atio n al H o sp itality M an ag em en t) / 1 9 Types of Pesticides Trade name Active ingredients (Ai) Registered for use on Toxic class (by WHO*) Original pesticides Marshal 200SC Carbosulfan Various crops II Synthetic pesticide Motsuper 36.0WG Acetamiprid Rice, vegetables II Synthetic pesticide Peran 50 EC permethrin Rice, vegetables II Synthetic pesticide Picmec 666 EC Chlorpyrifos Ethyl; Alpha -Cypermethrin ; Quinalphos Rice II Synthetic pesticide Regent 800WP Fipronil; Rice II Synthetic pesticide Rholam Super 50SG Emamectin benzoate; Matrine Rice, vegetables III Bio-pesticide Sieufatoc 36EC Abamectin; Emamectin benzoate Rice, vegetables, fruits II Synthetic pesticide Sokupi 0,5SL Martrine Rice, vegetables IV Bio-pesticide Spaceloft 595EC Alpha_cypermethrin; Chlorpyrifos Ethyl; Imidacloprid Various crops II Synthetic pesticide Scorpion 36EC Abamectin; Fipronil Rice, vegetables II Synthetic pesticide TaSieu 5WG Emamectin benzoate Rice, vegetables III Synthetic pesticide Tomuki 50 EC Hexy thiazox Flowers, vegetables IV Synthetic pesticide Tungent 5SC Fipronil Various crops II Synthetic pesticide Clothion 55EC Chlorpyrifos Ethy; Cypermethrin Rice, vegetable II Synthetic pesticide V.K 16WP Bacillus thuringiensis Vegatable, cotton IV Bio-pesticide Virtako 40WG Cholrantraniliprole; thiamethoxam Rice, vegetables, maize IV Synthetic pesticide F u n g ic id e (3 0 .9 % ) Agofast 80WP Fosetyl aluminium Various crops IV Synthetic pesticide Aliette Sosetil aluminium Rice, vegetables III Synthetic pesticide Carozate 72WP Mancozeb; cymoxanil Rice, vegetables III Synthetic pesticide Hong Duc University Journal of Science, E.5, Vol.10, P (24 - 31), 2019 20 F ac. o f G rad . 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(In tern atio n al H o sp itality M an ag em en t) / 2 0 Types of Pesticides Trade name Active ingredients (Ai) Registered for use on Toxic class (by WHO*) Original pesticides Cythala 75WP cymoxanil; Chlorothalonil Rice, water melon IV Synthetic pesticide Daconil 40WG Chlorothalonil Rice, vegetables III Synthetic pesticide Kasumin 2SL Kasugamycin Rice, vegetables, fruits IV Synthetic pesticide Mexyl MZ 72WP Metalaxyl; Mancozeb Rice, fruits IV Synthetic pesticide Ricide 72WP Metalaxyl; Mancozeb Fruits IV Synthetic pesticide Rido Xanil 750WP Cymoxanil; Mancozeb Rice, vegetables III Synthetic pesticide Score 250EC Difenoconazole Vegetables, fruits III Synthetic pesticide Strepa 150WP Streptomycinsulfate Rice, vegetables IV Synthetic pesticide Topsin M 70WP Thiophanate Methyl Rice, vegetables, fruits III Synthetic pesticide Totan 200 WP Bronopol Rice III Synthetic pesticide Validan 3SL Validamycin A Rice, vegetables IV Synthetic pesticide Validacin 5L Validamycin A Rice, vegetables IV Synthetic pesticide ZIMVIL 720 WP MEtalaxyl; Mancozeb Rice, vegetables, fruits IV Synthetic pesticide Zithane Z 80 WP Zinneb Tomato, grape III Synthetic pesticide H er b ic id e (7 .2 % ) Fansipan 200SL Paraquat ion Various crops II Synthetic pesticide Gfaxone 20 SL Paraquat ion Various crops II Synthetic pesticide Power up 275 SL Paraquat Dichloride Rice II Synthetic pesticide Vocal 276 SL Paraquat Dichloride Various crops II Synthetic pesticide *WHO: World Health Organization; II – moderately hazardous; III – slightly hazardous; IV-unlikely to present acute hazard in normal use. Hong Duc University Journal of Science, E.5, Vol.10, P (13 - 23), 2019 21 F ac. o f G rad . S tu d ies, M ah id o l U n iv . M . M . (In tern atio n al H o sp itality M an ag em en t) / 2 1 Supplementary Table 2. Pesticide use practices of vegetable growers in studied locations Unit: (%) percentage of household Survey question Delta areas (n=180) Coastal areas (n=180) Inland areas (n=90) Mean (n=450) 1. Selecting a pesticide Extension workers‟ recommendation 34,44 27,78 30,00 30,89 Neighbours‟ recommendation 36,11 18,89 58,89 33,78 Authorized dealer 56,67 63,33 76,67 63,33 Personal experience 78,89 45,00 53,33 60,22 2. Pesticide application timing Early morning 13,33 11,67 2,22 10,44 Moring 36,11 35,00 36,67 35,78 Afternoon 41,11 44,44 55,56 45,33 Other 9,44 8,89 5,56 8,44 3. Decision to apply pesticide Extension worker‟s recommendation 13,33 10,00 8,89 11,11 Noticing crop damage 39,44 41,67 54,44 43,33 Neighbour‟s recommendation 47,22 48,33 36,67 45,56 4. Apply pesticide at higher rate than permitted by the label Yes 77,78 81,01 83,33 80,22 No 22,22 18,99 16,67 19,78 5. Pesticide spraying techniques in the field Spray with the wind direction 27,22 23,33 22,22 24,67 Spray with zig zag model 69,44 68,33 70,00 69,11 Other 3,33 8,33 7,78 6,22 6. Read pesticide label carefully before mixing and applying Yes 21,11 6,11 7,78 12,44 No 78,89 93,89 92,22 87,56 7. Respect the recommended pre- harvested interval written on package label unnoticed 6,67 8,33 8,89 7,78 No 47,78 51,11 61,11 51,78 Yes 45,56 40,56 30,00 40,45 8. Protective measures during spraying 8.1. Mask Never 1,11 0,00 0,00 0,44 Hong Duc University Journal of Science, E.5, Vol.10, P (24 - 31), 2019 22 F ac. o f G rad . S tu d ies, M ah id o l U n iv . M . M . (In tern atio n al H o sp itality M an ag em en t) / 2 2 Rarely 2,22 2,78 2,22 2,44 Occasionally 6,11 6,11 8,89 6,67 Regularly 90,56 91,11 88,89 90,44 8.2. Gloves Never 22,22 21,11 16,67 20,67 Rarely 30,56 31,11 25,56 29,78 Occasionally 39,44 33,89 42,22 37,78 Regularly 7,78 13,89 15,56 11,78 8.3. Boots Never 2,78 21,11 12,22 12,00 Rarely 10,00 50,00 23,33 28,67 Occasionally 34,44 25,56 50,00 34,00 Regularly 52,78 3,33 14,44 25,33 8.4. Hat Never 7,22 5,56 3,33 5,78 Rarely 10,00 7,78 5,56 8,22 Occasionally 20,00 16,11 12,22 16,89 Regularly 62,78 70,56 78,89 69,11 8.5. Raincoat or safety clothes Never 21,11 24,44 26,67 23,56 Rarely 50,00 43,33 42,22 45,78 Occasionally 21,11 23,33 28,89 23,56 Regularly 7,78 8,89 2,22 7,11 9. Leftover pesticides Spray until no pesticide left 88,89 94,44 91,11 91,56 Dump in the field 8,89 5,56 1,11 6,00 Spray other crops 2,22 0,00 7,78 2,44 10. Disposal empty pesticide containers are Kept in safe place 62,78 38,89 35,56 47,78 Left in field 37,22 55,56 56,67 48,44 other 0,00 5,56 7,78 3,78 11. Cleaning pesticide application equipment In field 75,00 97,22 90,00 86,89 In safe place 21,11 2,78 6,67 10,89 House 3,89 0,00 3,33 2,22 Hong Duc University Journal of Science, E.5, Vol.10, P (13 - 23), 2019 23 F ac. o f G rad . S tu d ies, M ah id o l U n iv . M . M . (In tern atio n al H o sp itality M an ag em en t) / 2 3 References [1] Hoi P.V., et al. (2016), Pesticide use in Vietnamese vegetable production: a 10-year study. International Journal of Agricultural Sustainability, 14: 325-338. [2] Hurtig A.K., et al. (2003), Pesticide use among farmers in the Amazon basin of Ecuador. Archives of Environmental Health, 58: 223-228. [3] Jansen, H. C. & Harmsen, J. (2011), Pesticide monitoring in the Central Rift Valley 2009- 2010: Ecosystems for water in Ethiopia. Wageningen, Alterra, Alterra-rapport 2083. [4] Jeyanthi H., Kombairaju S. (2005), Pesticide use in vegetable crops: frequency, intensity and determinant factors. Agricultural Economics Research Review, 18: 209-221. 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