Pesticide Use and Health Effects among Nepalese Farmers: A Cross-Sectional Study in Tokha Municipality

Abstract

Background:

Pesticides are essential for agricultural development, but their increased use in developing countries like Nepal poses health risks to farmers.

Methods:

A cross-sectional study was conducted in wards 1, 2, and 3 of the Tokha Municipality in Kathmandu District to identify the health effects of pesticides and associated factors among farmers. The study included 333 respondents who were interviewed between April 26 and June 04, 2022.

Results:

The majority of farmers (36.6%) were aged between 40 and 49 years, with a median (IQR) age of 45.0 (38.0 to 51.0) years. All farmers reported using pesticides, with 100% usage in vegetables. Most respondents (73%) reported experiencing health effects: headache (69.5%), skin irritation (42.8%), and burning eyes (31.3%) were the most common symptoms. Only 8% sought medical care. Additionally, 94.6% of respondents had not received training on integrated pest management, and none of them reported using a complete set of personal protective equipment. The study found that older age groups, females, those who were unable to read and write, and those of the Hindu religion, as well as respondents with longer pesticide use, more frequent spraying, and not detecting wind direction, had significantly higher odds of self-reported health problems (P < 0.05).

Conclusion:

Our findings show that all farmers in the study were using pesticides, and the majority had reported health effects. Therefore, we recommend that farmers receive training on integrated pest management, use a complete set of personal protective equipment, and promptly seek medical care if they experience health issues.

INTRODUCTION

Pesticides are vital for agriculture and public health.[1,2] However, exposure to pesticides can lead to health problems such as respiratory, integumentary, cardiovascular, gastrointestinal, and neurological issues.[1,3] Although the increase in global pesticide use has slowed down since the 1990s, many developing countries still experience significant increases in pesticide use.[4,5] Globally, an estimated 1–41 million people are affected each year, with at least 300,000 deaths, and low- and middle-income countries accounting for 99% of those fatalities.[6]

Pesticide exposure is a common issue among farmers in Nepal, where over 66% of the population is engaged in agriculture.[7,8,9] Pesticide usage is increasing annually at a rate of 10–20%, with an average application of 396 g/ha. Commonly used pesticides in Nepal include organochlorines (such as Benzene Hexachloride and Dieldrin), organophosphates (including ethyl parathion, and methyl parathion), carbamates, and synthetic pyrethroids.[10] Unfortunately, farmers often lack awareness about pesticide types, their toxicity levels, safety precautions, and the risks they pose to human health and the environment.[11,12] Additionally, there is a shortage of personal protective equipment (PPE) and inadequate education on proper PPE use and spraying techniques, further increasing the risk of pesticide exposure for farmers.[3]

Limited research has been conducted in Nepal on pesticide issues, and there is little information available on the country's pesticide poisoning situation. It is concerning that information related to pesticide hazards is not included in the routine national health management and information system.[9,13] Despite numerous published studies on the topic, very little epidemiological data is available to assess the health impacts of pesticides on humans.[11,14] Therefore, our study aims to identify the health effects of pesticides and associated factors among Nepalese farmers.

MATERIALS AND METHODS

Study design and population

A cross-sectional study, based in the community, was conducted among farmers in Ward No. 1, 2, and 3 of Tokha Municipality in Kathmandu District. The study included farmers who were aged 18 years or older.

Sample size and sampling technique

The sample size for the study was determined using the Cochran formula (n = Z²pq/e²). The estimated proportion of farmers experiencing skin problems due to pesticides (p) was determined to be 26.6%.[15] A Z score (Z) of 1.96 was used for a 95% confidence level, and an acceptable sampling error (e) of 5% was chosen. Accounting for a 10% response rate, the final sample size was estimated to be 333. A purposive sampling technique was employed to select all the respondents.

Data collection tools and technique

To collect data, semi-structured questionnaires were used. The questionnaires were self-constructed and included some questions from a previous study conducted by the Nepal Health Research Council.[16] Prior to data collection, the questionnaire was validated by subject experts. The tools were pretested on 10% of the sample population and revised accordingly. Face-to-face interviews were conducted by trained data collectors working under the close supervision of researchers from April 26 to June 04, 2022. The researchers obtained a list of farmers from the local ward office and visited each house of the selected respondents, making multiple attempts if necessary. The interview forms were reviewed daily for completeness and rechecked by the researcher for accuracy. Non-respondents were those who could not be reached after two attempts.

Data analysis

We conducted a statistical analysis using SPSS version 26. Descriptive statistics were used to analyze demographic information, pesticide practices, safety measures, storage/disposal, and self-reported health effects. The Chi-square test was used to identify factors associated with farmers’ self-reported health effects. Logistic regression analysis was performed to determine predictors of health effects and generated odds ratios (ORs) and adjusted odds ratio (AORs) with 95% CIs. P < 0.05 was considered significant.

Ethical consideration

The study was approved by the institutional Review Committee of Yeti Health Science Academy. Respondents provided written informed consent. Permission to collect data was granted by the ward office, and confidentiality was maintained to protect privacy. No financial incentives were given.

RESULT

Socio-demographic characteristics of the sample

The study included 333 respondents with diverse demographic characteristics. The majority were married (88.3%, n = 294), lived in nuclear families (88.9%, n = 296), and were involved in non-commercial farming (80.8%, n = 269). The median (IQR) age was 45.0 (38.0 to 51.0) years, and 52% (n = 173) were male. Most respondents (62.2%, n = 207) reported being unable to read and write. Janajati group (55.6%, n = 185) was the largest ethnic group, and 97% (n = 323) of the respondents were Hindu [Table S1].

Table S1:

Socio-demographic characteristics of the sample

Variables	Frequency (n)	Percentage (%)
Age (median, interquartile range)	45.0,38.0 to 51.0
Age in years
>20	3	0.9
20-29	16	4.8
30-39	83	24.9
40-49	122	36.6
50-59	83	24.9
60>	26	7.8
Sex
Male	173	52
Female	160	48
Educational Status
Cannot read and write	126	37.8
No-formal education	47	14.1
Basic Level (Grades 1-8)	80	24
Secondary Level (Grades 9-12)	74	22.2
University education	6	1.8
Marital Status
Unmarried	10	3
Married	294	88.3
Widow/widower	29	8.7
Ethnic Group
Brahmin/Chettri	142	42.6
Janajati	185	55.6
Dalit	6	1.8
Religion
Hindu	323	97
Buddhist	10	3
Family Type
Nuclear	296	88.9
Joint	37	11.1
Type of farming
Commercial	64	19.2
Non-commercial	269	80.8

Pesticides use, practices, and safety measures

Most farmers (32.4%, n = 108) had been farming for 1–9 years, with a mean of 17.31 (±12.23) years. Nearly half of the respondents (46.2%, n = 154) had used pesticides for 5–10 years on vegetables, and 49.2% (n = 164) also used pesticides on paddy. Among pesticide users, 83.2% (n = 277) sprayed <3 times per month, and 65.8% (n = 219) checked wind direction before spraying. All respondents (100%) used PPE, with masks (94%, n = 313) being the most common. Full body covering (76.9%) was also frequently used. The majority (94.6%, n = 315) had not received integrated pest management training (IPM) [Table 1].

Table 1:

Pesticides use, practices, and safety measures

Variables	Frequency (n)	Percentage (%)
Mean (years) ± SD	17.31±12.23
Years of working on a farm
1–9	108	32.4
10–19	79	23.7
20–30	105	31.5
<30	41	12.3
Years of using pesticides
1–5 years	133	39.9
5–10 years	154	46.2
10> years	46	13.8
Types of crops on which pesticides are sprayed*
Vegetables	333	100
Paddy	164	49.2
Maize	105	31.5
Number of sprays per month
>3 times	277	83.2
<3 times	56	16.8
Determining wind direction before spraying
Yes	219	65.8
No	114	34.2
Use of PPE*
Spectacles	58	17.4
Mask	313	94
Cap	211	63.4
Gloves	74	22.2
Full body covering	256	76.9
Boots	51	15.3
IPM training
Yes	18	5.4
No	315	94.6

*Multiple responses

Pesticide storage and disposal practices

Significant number of farmers stored their pesticides in locked stores or boxes (40.2%, n = 134), while almost the same proportion (39.3%, n = 131) kept them in areas that were not easily accessible to children. Almost all farmers (97.6%, n = 325) stored their pesticides in their original containers. In terms of pesticide disposal, the majority burned the pesticides (45.9%, n = 153), followed by burying them (29.1%, n = 97), and giving them to garbage collecting trucks (18.6%, n = 62) [Table S2].

Table S2:

Pesticide Storage and Disposal Practices

Variables	Frequency (n)	Percentage (%)
Place of pesticide storage
Locked in store/box	134	40.2
Out of children reach	131	39.3
Buy and use immediately	71	21.3
Containers used for pesticide storage
Original box	325	97.6
Other containers	8	2.4
Disposal of used pesticide containers or packets
Burning	153	45.9
Burial	97	29.1
Rag pickers	35	10.5
Garbage collecting truck	62	18.6

Self-reported health effects of pesticides

After pesticide spraying, 73% of respondents (n = 243) reported experiencing health problems within a month. The most common symptoms reported by the 243 respondents were headaches (69.5%, n = 169), skin irritation (42.8%, n = 104), burning eyes (31.3%, n = 76), dizziness (22.6%, n = 55), and extreme tiredness/excessive sweating (21.85%, n = 53). 92.6% of the respondents (n = 225) sought help immediately after experiencing symptoms, with 99.6% of them (n = 224) preferring to rest and only 8% (n = 18) seeking medical treatment at a healthcare facility [Table 2].

Table 2:

Self-reported health effects of pesticides

Variables	Frequency (n)	Percentage (%)
Feelings of illness in the last month after spraying pesticides
Yes	243	73
No	90	27
If yes, reported symptoms (n=243)*
Headache	169	69.5
Skin irritation	104	42.8
Burning eyes	76	31.3
Dizziness	55	22.6
Extreme tiredness	53	21.8
Excessive sweating	53	21.8
Health-seeking behaviors (n=243)
Yes	225	92.6
No	18	7.4
If yes, the types of health-seeking behaviors used to follow (n=225)*
Self-medication	68	30.2
Health institution visit	18	8
Resting	224	99.6

*Multiple responses

Factors associated with the health effects of pesticide use

Logistic regression analysis was used to identify variables significantly associated with health effects. The models used were found to be adequately fit, as demonstrated by Omnibus Tests of Model Coefficients (χ² = 42.811, P < 0.001) and Hosmer and Lemeshow Test (χ² = 8.757, P > 0.05). The results of the analysis showed that older age groups, particularly those aged 65 and above, had higher odds of experiencing health effects (AOR = 27.5, 95% CI 2.15–350.10, P = 0.011), as well as females (AOR = 3.2, 95% CI 1.81–5.69, P < 0.001), illiterate individuals (AOR = 2.8, 95% CI 1.58–4.87, P < 0.001), those with no-formal education (AOR = 3.4, 95% CI 1.42–8.07, P = 0.006), and those who identified as Hindu (AOR = 5.0, 95% CI 1.29–19.17, P = 0.020) [Table 3].

Table 3:

Association between selected variables and health effect among farmers: Crude and adjusted odds ratios

Variables	Health effect n (%)	Crude OR			Adjusted OR**
		OR	95% CI	P	AOR	95% CI	P
Age
15–24 (Ref.)	4 (50.0)	1.0	-	-	1.0	-	-
25–64	229 (72.9)	2.7	0.66–11.01	0.168	4.3	0.97–18.85	0.055
65>	10 (90.9)	10.0	0.84–119.32	0.069	27.5	2.15–350.10	0.011*
Sex
Male (Ref.)	108 (62.4)	1.0	-	-	1.0	-	-
Female	135 (84.4)	3.0	1.71–5.31	<0.001*	3.2	1.81–5.69	<0.001*
Education
Formal Education (Ref.)	99 (61.9)	1.0	-	-	1.0	-	-
Cannot read and write	104 (82.5)	2.9	1.66–5.10	<0.001*	2.8	1.58–4.87	<0.001*
Non-formal education	40 (85.1)	3.5	1.48–8.35	0.004*	3.4	1.42–8.07	0.006*
Religion
Buddhist (Ref.)	4 (40.0)	1.0	-	-	1.0	-	-
Hindu	239 (74.0)	5.1	1.34–19.80	0.017	5.0	1.29–19.17	0.020*
Years of working as farmer
1–9 Years (Ref.)	66 (61.1)	1.0	-	-	1.0	-	-
10–19 years	58 (73.4)	1.8	0.94–3.31	0.080	1.7	0.89–3.33	0.107
20–30 years	85 (81.0)	2.7	1.45–5.03	0.002*	2.6	1.18–5.64	0.018*
<30	34 (82.9)	3.1	1.26–7.61	0.014*	2.8	0.81–9.87	0.103
Years of using pesticides
1–5 (Ref.)	83 (62.4) 1	1.0	-	-	1.0	-	-
5–10	121 (78.6)	1.8	1.03–3.31	0.040*	1.7	0.95–3.12	0.071
<10	39 (84.8)	3.0	1.10–8.00	0.032*	2.8	1.04–7.67	0.042
Number of sprays per month
>3 times (Ref.)	198 (71.5)	1.0	-	-	1.0	-	-
<3 times	45 (80.4)	1.9	0.80–4.42	0.148	2.7	1.06–6.62	0.037*
Determining wind direction before spraying
Yes (Ref.)	151 (68.9)	1.0	-	-	1.0	-	-
No	92 (80.7)	1.9	1.10–3.25	0.023*	1.9	1.10–3.42	0.025*
Use of spectacles
Yes (Ref.)	33 (56.9)	1.0	-	-	1.0	-	-
No	210 (76.4)	2.9	1.36–6.16	0.006*	3.1	1.43–6.56	0.004*

*Factors with P<0.05 were considered statistically significant **Adjusted for age and sex

Furthermore, the study found that respondents with 20–30 years of farming experience (AOR = 2.6, 95% CI 1.18–5.64, P = 0.018), using pesticides for over 10 years (AOR = 2.8, 95% CI 1.04–7.67, P = 0.037), spraying more than three times per month (AOR = 2.7, 95% CI 1.06–6.62, P = 0.037), not checking wind direction before spraying (AOR = 1.9, 95% CI 1.10–3.42, P = 0.025), and not wearing protective spectacles while spraying pesticides (AOR = 3.1, 95% CI 1.43–6.56, P = 0.004) were significantly associated with experiencing health effects [Table 3].

DISCUSSION

This study found that the majority of participants were male, illiterate, with a mean age of 44.78 years, which is consistent with similar studies in Nepal and Iran.[8,17] All the farmers in our study used pesticides, which is consistent with previous literature.[18] Our analysis revealed that 46.2% of the farmers had been using pesticides for 5–10 years, which is consistent with findings from previous studies conducted in Nigeria,[19] and study by Rostami et al.[20] However, our study found that most farmers applied pesticides <3 times per month, unlike a study in Chitwan,[21] Nepal where farmers applied pesticides up to four times per month.

Our study found that all respondents used PPE, but not in its complete set, consistent with Joko et al.’s findings.[22] In contrast, a study conducted in Ghana reported that only 30.9% of workers used PPE,[23] and Bhattrai et al.[24] found that almost 12% of participants did not use any PPE while applying pesticides, suggesting variations in study areas and sample sizes. Masks were the most commonly used PPE in our study, aligning with Khanal and Singh's finding.[21] The majority of farmers in our study lacked IPM training, which corresponds with prior research indicating that most farmers lack sufficient knowledge and training in safe pesticide handling.[8]

Our study found that farmers stored pesticides in a secure storage box in a separate room, consistent with a study in Pakistan.[25] In contrast, other studies by Bhattrai et al.,[24] and Sharma,[26] reported that most people stored pesticides in their homes without restrictions, in accessible locations, and only a small percentage stored pesticides in closed containers or stores.

Most participants in our study burned used pesticide containers, consistent with an earlier study.[27] However, many people dispose of containers improperly, such as in water channels, canals, or near their houses, or even use them for storing food or throw them in open fields.[21,25,28] The majority of farmers experienced health effects within the last month after using pesticides, similar to previous studies.[8,29,30] Similar to our findings, previous studies have shown that headaches, skin irritation, burning eyes, excessive tiredness, and dizziness were the most frequently reported symptoms.[31,32] However, only 8% of farmers sought medical treatment for these health effects, similar Lekei et al.'s findings,[33] which reported that 79% of farmers did not seek medical attention despite experiencing health issues.

Similar to a study in southwest Iran,[34] we found that older adults (65+) had higher odds of self-reported health effects. Illiterate respondents also had higher odds of health effects, as in an Indian study.[35] Farmers who sprayed pesticides more than three times per month had a significantly higher risk of health problems, as in a study in rural western Iran.[30] Other factors associated with health problems included spraying without checking wind direction and having 20–30 years of farm experience.[8] Not using PPE, especially spectacles, also increased the risk of health problems, consistent with studies from India[35] and Northern Tanzania.[36]

This study was conducted among 333 farmers in three municipal wards, which may limit the generalizability of the findings due to the small sample size and limited study area. Additionally, the self-reported health effects and purposive sampling technique used may introduce informational and selection bias.

CONCLUSION

Based on our study, we found that all participants used pesticides, and the majority experienced health problems. Seeking medical care was also neglected. Few received IPM training, and PPE use was inadequate. Socio-demographic characteristics and pesticide exposure level raised the risk of health problems. However, no significant association was found between training or PPE use, except for spectacles, and health effects. Further research is needed. We suggest IPM training for all farmers, complete PPE use, immediate medical attention if a health problem arises, free or low-cost IPM training, farmer education, accessible PPE, and regular health screenings organized by the municipality.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.