Developing countries have been experiencing a significant shift in food consumption habits in recent decades. The relative importance of high-value commodities including vegetables is steadily increasing in South Asia in recent years [1
]. Fresh vegetable production in Nepal has increased at an average annual rate of 6.9% between the year 2000 and 2010, with an increased production area by 5% [2
]. Fresh vegetable production in 2014 occupied approximately 254,932 ha area of Nepal with a total vegetable production of 3,421,035 metric tons [3
]. The per capita vegetable consumption of Nepal increased from 60 kg to 105 kg in last two decades [2
]. However, fruit and vegetable consumption in Nepal is still below the WHO recommended level [4
]. Chitwan district is one of the consistent vegetable suppliers for the major vegetable market of the country including the capital city, Kathmandu. The area under vegetable production in Chitwan has increased significantly in recent years. Currently, Chitwan is ranked third among major vegetable producing districts in Nepal, with an annual production of 87,560 metric tons from a 6369 ha area [3
]. With this increase in vegetable production, there is also an increase in the use of production inputs such as chemical fertilizers and other plant nutrients, crop seeds, and pesticides.
Commercial vegetable production in Nepal heavily relies on chemical pesticides [5
]. However, there is neither a comprehensive record of the amount of pesticide import and use in agriculture nor the effect of pesticides on human or environmental health [6
]. A study reported an estimated annual import of 211 metric tons of pesticides, primarily fungicides (51.38%), followed by insecticides (29.19%) and herbicides (7.4%) [7
]. The southern plain region (Terai), also called the ‘food basket’ of the country, uses the highest amount of pesticide per unit area followed by the mid-hills and high-mountains regions [8
]. With the increase in pesticide use, the associated potential risk to human health and the environment is a concern. Repeated use of single or limited pesticide active ingredients (a.i.), use of higher rates of pesticide than needed, and lack of user knowledge on pesticide type and toxicity are some of the current major issues associated with the pesticide use in Nepal [9
]. Several chemical pesticides used in agriculture are known to cause health problems in human, livestock, and produce an adverse impact on plant diversity and environment in both short and long run [6
]. Improper pesticide handling causes accidental poisoning, and even acute or chronic health effects [7
]. In long run, pesticide exposure can cause long-lasting health issues such as dermatosis, cancer, and genotoxic, neurotoxic, and respiratory effects [12
]. In developing countries, the use of outdated, non-patented, more toxic, and environmentally persistent pesticide are the leading causes of higher toxicity [13
]. In addition, farmers in developing countries are exposed to toxic chemicals due to a lack of technical knowledge on toxicity levels of pesticides and safety measures to protect themselves from the exposure [6
]. The improper handling of pesticide occurs mainly at the time of mixing and application, during storage, and during pesticide disposal [7
There have been several studies conducted in past decades which have focused on the use of chemical pesticides in South Asia, and their consequences if handled improperly. One report in China indicated that majority of farmers were unaware of proper disposal of pesticides, and habituated to dispose in sensitive areas such as streams and rivers [18
]. Many farmers in South Asian countries—including Pakistan, India, and Thailand—are using WHO-rated highly toxic and, in some cases, banned pesticides without knowing the consequences to their health and environment [19
]. In Nepal, few studies have been conducted on pesticide use knowledge and practices. According to a household survey in Kavre district [6
], one of the districts with intensive commercial agriculture reported that female members of the family were exposed more to pesticides than male because of their involvement in the vegetable production. In Chitwan, one case study was conducted to test the farmers’ attitudes and knowledge about vegetable production and pest management, however, the study was focused only in one vegetable growing community [5
]. Thus, a comprehensive work representing multiple vegetable production areas in the district is lacking. Our study was focused on evaluating the current status of pesticide use, and to assessing farmer knowledge on safe pesticide handling at six major commercial vegetable producing areas of the district. Such information will help in improving awareness to the farmers and related stakeholders such as agricultural technicians, and extension agents to conduct training or awareness programs for addressing specific needs.
2. Materials and Methods
2.1. Study Area and Selection of Vegetable Growers
The study was conducted in six commercial vegetable growing villages in the western Chitwan, Nepal in spring 2016. The study area was approximately 120 km southwest of the capital city, Kathmandu. The six villages are located within the 20-km radius from Rampur (GPS coordinates: 27°39′04.89″ N and 84°20′57.47″ E), the central location of the study area (Figure 1
). The area has tropical monsoon climate with high relative humidity throughout the year. The monsoon season starts in June and ends in September. The average temperatures of the study area during the hottest (May) and coldest (January) months are 29.2 °C and 15.7 °C, respectively. Chitwan district is spread across an area of 223,839 ha and has a population of 472,048. A total number of households in the district is 92,863 with an average household size being five people per family [22
]. Nearly 35% of the total land is agricultural that includes pasture land, and ~31% of the total population is engaged in agriculture [23
]. Six farmer groups representing the six-major vegetable growing villages in western Chitwan were selected for the study. These farmer’s groups (30 households in an individual group) were identified based on grower registration information of District Agriculture Development Office (DADO), Chitwan. All study areas were identified and listed as a pocket area for fresh vegetable production by DADO Chitwan. The vegetable production is seasonal, mainly follows the rice–vegetables–corn cropping rotation. The study area is close to the Agriculture and Forestry University, and highly accessible to all major cities linked to the central transportation system. Crucifers (cabbage, cauliflower), solanaceous (potato, tomato, eggplant, sweet pepper), and cucurbitaceous (cucumber, gourd, melons) crops are major vegetable crops grown in the area.
2.2. Survey Approach and Questionnaire Development
This study is a part of an interdisciplinary project to identify pesticide use knowledge and practices among vegetable grower, and then conduct a training program to address those issues among selected farmers. Of total 180 farmers selected for training, by the Center for Agricultural Research and Development (CARD-Nepal), a total 100 farmers (56% of total study population) were administered with an informed consent questionnaire. The stratified random sampling (16 farmers from each of the first two groups; and 17 from each of the remaining four groups) was used to select respondent households. The key informants’ survey was used for a sampling frame, and survey respondents were selected after a pre-field visit. The majority of respondents had long-standing experience in vegetable production.
The semi-structured questionnaire (also referred to as a mixed questionnaire) consists of both closed and open-ended questions. The closed-ended questions have multiple options as answers and allow respondents to select a single option. The open-ended questions allow the participants to provide their answers without using any structured options. The questionnaire was first pretested with five households, adjusted as needed, and used to understand farmers’ attitudes towards pesticide use, knowledge, and practices. The questionnaire was divided into three broad sections. The first section related to the socio-demographic questions to know the age, education level, income, landholding, purpose of agriculture, source of income, vegetable production experience, and other related information. The second section included current pest management practices and pesticide use patterns. The specific topics covered in this section included pest control methods, rates, and frequencies of pesticide use, decision-making on the selection of pesticide, spray timing, and other considerations. The third section included the technical know-how of farmers about pesticide safety and pesticide exposure issues such as understating the pesticide label, pesticide toxicity label, pesticide mode of action, pesticide residuals, pesticide resistance, and technical knowledge about integrated pest management (IPM).
2.3. Data Analysis
A descriptive statistics and frequency distribution analysis were conducted among all parameters obtained. A Chi-square test was used to determine an association between parameters in socio-demographic characteristics, pesticide use pattern, exposure, and other qualitative variables (p < 0.05). The software ver. 21 SPSS (IBM Corp., Armonk, NY, USA) and Microsoft Excel (Microsoft Corp., Redmond, WA, USA) were used in data analysis.
Insect, pest, and disease management are primary constraints to commercial vegetable production in developing countries such as Nepal. Farmers use chemical pesticide as an effective pest control measure. The current study aimed to assess farmers’ knowledge on pesticide use and handling, and evaluate their current pest management practices in commercial vegetable production. The study found that most of the farmers’ knowledge on several aspects of a pesticide such as its use, types, characteristics, selection, and overall handling is very limited. Improper handling and indiscriminate use of pesticides can increase health-related risks and expenses to both farmers and consumers. Farmers use chemical pesticides without considering insect pest monitoring and economic thresholds, pesticide label instructions, pre-harvest interval requirement, proper use of personal protective equipment and clothing, potential impact on non-targets and the environment, which collectively form the basis of IPM. The influence of the government agricultural extension program on improving farmer’s knowledge on pesticide use appears inadequate, and farmers solely depend on local pesticide retailers for technical guidance. Poor pesticide safety and use situations are attributable to weak pesticide regulatory and enforcement systems. This study also emphasized the importance of understanding farmers’ local situations and educating farmers on several aspects of pesticide use, disposal, and consequences of improper and illegal use. This information will guide policymakers to prioritize their programs and appropriately enforce the sale and use of chemical pesticides to mitigate all environment and health-related consequences. Solving such issues requires a coordinated effort of all stakeholders—farmers, private pesticide retailers, and consultants; government extension agencies at both national and local levels; and other pesticide enforcement agencies.