Small-scale Farmer Pesticide Knowledge and Practice and Impacts on the Environment and Human Health in Ethiopia

Integrated Biomarker Response Emphasizing Neuronal Oxidative Stress and Genotoxicity Induced by Oxamyl in Sprague Dawley Rats: Ameliorative Effect of Ginseng as a Neuroprotective Agent

Climate change has led to increased and varying pest infestation patterns, triggering a rise in pesticide usage and exposure. The effects of oxamyl, a widely used nematicide in Egypt, encompasses typical signs of carbamate intoxication; nevertheless, long-term effects of oxamyl exposure, particularly on the nervous system, require further elucidation. This study systematically investigated the mechanism and manifestations of repeated subacute exposure to sublethal doses of oxamyl in male SD rats. Data showed a dose-dependent genotoxic effect, manifested as increased bone marrow micronuclei and decreased brain expression of key genes involved in neurogenesis and neuronal development. Coincidently, brain histopathology showed dose-dependent neurodegeneration in various regions, associated with a significant increase in GFAP immunoreactivity, indicative of neuroinflammation. Biochemical examination revealed a typical pattern of cholinesterase inhibition by carbamates in serum and brain tissue, as well as increased oxidative stress markers in the brain such as SOD activity reduction, alongside an increase in NO and MDA. The ability of Ginseng at a 100 mg/Kg dose to ameliorate the effects of oxamyl exposure was investigated. Ginseng use, either as a protective or therapeutic regimen, attenuated the observed genotoxic, neuroinflammatory, and biochemical alterations. Our results indicate that repeated exposure to oxamyl triggers an integrative neurotoxic response, driven by genotoxicity, oxidative stress, and neuroinflammation, that could trigger an increase in neurological and cognitive disorders. These findings emphasize the urgent need for confirmatory translational studies in human subjects to assess these changes and inform policy decisions regarding safe levels of usage and appropriate agricultural and public health practices.

Knowledge, attitudes, and perceptions of farmers towards urban agroecology in Malaysia

Adopting agroecological approaches to build resilient urban food systems has recently gained traction around the world, but there is little to no reliable literature on the knowledge, attitudes, and perspectives of urban farmers towards these nature-based solutions in many developing nations, including Malaysia. The present study conducted an online survey to determine the extent to which local urban farmers understand and employ agroecology, as well as to assess their awareness and views on using agroecological practices and sustainable farm management. We found that the majority of respondents are unfamiliar with agroecological principles, with 79 % agreeing or strongly agreeing that implementing sustainable agricultural practices is challenging. However, more than 90 % of respondents are aware of the environmental consequences of excessive input utilisation. Our findings highlight the need for improved initiatives to promote agroecological approaches among farmers by sharing knowledge and best practices. In light of the growing threat posed by urban heat islands and the rapid urbanisation, this study offers novel insights into the knowledge gaps and perceptions about agroecological approaches among urban farmers, challenges that must be addressed to promote sustainable agriculture, and the potential role of farmers in achieving the three fundamental pillars of sustainability-planet, people, and prosperity.

Small-scale market gardeners' knowledge, attitudes and practices regarding the use of chemical pesticides in the Kabare territory (South-Kivu) in Eastern D.R. Congo

Damage caused by pests and diseases is one of constraints on crop production for food security. Based on the use of questionnaire and interviews that were conducted in Kabare territory (South-Kivu), this study was carried out to (i) assess farmers practices, attitudes, and knowledge about pesticides use, and (ii) assess the human health and physical environment effects using pesticides. Data was collected from 300 small-scale farmers in study area. Results showed that majority of our respondents were men (59 %) rather than women (41 %) and local knowledge of pesticide use was low (60 %). Education level had a significant influence (p < 0.01) on level of knowledge about pesticide use, time and dose of treatment, method of control, and persistence time. In addition, education level influence significantly farmers' attitudes before and after pesticide treatment (p < 0.05). Pest management control, time of pesticide application, and packaging management method varied significantly with level of local knowledge (p < 0.01). Pesticides use by small-scale farmers has an effect on water, soil, and air quality. It also causes human pathologies such as vomiting, eye irritation, and even loss of life in event of heavy exposure. Inhalation and dermal exposure are main and most dangerous routes of pesticide exposure in our study area, which lacks protective strategies. Finally, use of pesticides disrupts biodiversity through the disappearance of pollinators, predators, parasitoids, and soil microorganisms. Therefore, broad continuity of this study with integration of other scientific aspects would effectively contribute to the improvement of environmental quality.

Pesticides residues in leafy green vegetables and irrigation waters in Accra, Ghana

Pesticides are used in vegetable farming to control pests and diseases, reduce crop losses and improve yield. The study examined pesticide residues in irrigation waters and leafy green vegetables grown in some farming areas in Accra, Ghana. Three types of irrigation water sources (n = 23) and two exotic and four indigenous Ghanaian leafy vegetables (n = 34) from 10 farming areas in Accra, Ghana were collected and examined for 15 organochlorines, 13 organophosphorus and 9 synthetic pyrethroids pesticide residues using the modified QuEChERS procedure. Pesticide residues were detected on 50% (17/34) of the leafy vegetable and 52% (12/23) of the irrigation water samples analysed. Chlorpyrifos and deltamethrin were the most detected pesticide residues in the vegetables and irrigation water. About 26.5% of the vegetables contained pesticide residues exceeding the EU maximum residue limits, so vegetable farmers should be encouraged to comply with appropriate measures on pesticide use to enhance food safety.

Analyzing Factors Affecting Farmers' Safe Pesticide Handling Practices in Southwest of Ethiopia: Implications for Policy

Background

Pesticides play a crucial role in enhancing agricultural productivity by controlling pests. However, inadequate pesticide handling practices have a considerable adverse impact on human health. Nevertheless, there is limited knowledge regarding the extent of safe pesticide handling practices, particularly in low-income settings like Ethiopia. Hence, this study seeks to evaluate the implementation of safe pesticide handling practices and identify the factors associated with the status of the handling practices in low-income settings in Ethiopia.

Methods

A cross-sectional study was undertaken, involving 468 farmers randomly selected for participation. Data collection was carried out through structured questionnaires and face-to-face interviews. The analysis aimed to assess the proportion of safe pesticide handling practices (SPHP) and investigate the factors associated with SPHP was done using binary logistic regression. Explanatory variables with a P-value <0.25 were included in the final analysis. The factors were determined based on adjusted odds ratios and 95% confidence intervals, P-value <.05. Model fit was evaluated using the Hosmer and Lemeshow tests.

Results

From the findings of our study, only 45.7% of farmers practiced SPHP, with factors such as education, experience, pesticide usage, and attitude toward safe practices influencing their practices. Farmers with education status primary and above were two times more likely to practice good handling of pesticides than those who didn't attend formal education. Farmers with a maximum of 5 years of experience in vegetable farming were 2.4 times more likely to exhibit good handling practices compared to their counterparts. Furthermore, farmers with favorable attitudes toward pesticide handling were 4.2 times more likely to engage in good pesticide handling practices than those with unfavorable attitudes. Therefore, the agricultural sectors, health sectors, and farmer associations should focus on these factors in order to mitigate the health risks associated with poor pesticide handling.

Risk perception and use of personal protective equipment (PPE) in pesticide use: does risk shape farmers' safety behavior?

Risk perception and use of personal protective equipment (PPE) in pesticide use were studied in 109 farmers of northern Greece. Farmers differed in the levels of pesticide risk perception, with 26.6% showing very low and low levels, 34.9% showing moderate levels, and 38.5% showing high and very high levels. Pesticide risk perception was positively correlated with education and large cultivated area, but negatively with age and non-farming as a main profession. Most farmers (82.6%) showed adequate use of PPE (mostly face mask and gloves). The use of PPE was positively correlated with education and risk perception, but negatively with age and non-farming as a main profession. Farmers with high levels of risk perception used 1.3 and 2.6 times more PPE items than those with moderate and low levels of risk perception, respectively. High education was a positive predictor, whereas main profession other than farming was a negative predictor of PPE use.

Organochlorine, organophosphorus, and carbamate pesticide residues in an Ethiopian Rift Valley Lake Hawassa: occurrences and possible ecological risks

Currently, pesticide production and use are on the rise globally. This trend is certain to continue in the coming decades with residues posing risks to the environment and human health even at low levels. Although various aspects of pesticides and their possible implications have widely been studied, such studies have mostly been carried out in developed countries leaving the rest of the world with little scientific information. We present here the results of a study on the occurrences, concentrations, and ecological risks of 30 pesticide residues (PRs) in water and sediment samples from a tropical freshwater Lake Hawassa in the Ethiopian Rift Valley. A total of 54 composite samples of water and sediment were collected from three sampling sites on three occasions. The samples were prepared by quick, easy, cheap, effective, rugged, and safe (QuEChERS) technique, and analyzed using GC-MS at Bless Agri Food Laboratory Service located in Addis Ababa, Ethiopia. The study applied the risk quotient (RQ) method to scrutinize the risks posed to aquatic biota by the detected PRs. The results showed occurrences of 18 and 20 PRs in the water and sediment samples, respectively. The majority, 78 and 75% of the detected PRs in water and sediment samples, respectively represent the organochlorine chemical class. Concentrations of heptachlor epoxide were significantly (p ≤ 0.001) higher than those of the remaining pesticides in both matrices. Of the pesticides detected, 77% were present in water and 83% in sediment samples and pose a serious risk (RQ ≥ 1) to the Lake Hawassa biota. This calls for further research to investigate the risks to human health posed by the PRs. The findings of this study can contribute to the development of global protocols, as they support the concerns raised about the ecological and public health impacts of PRs on a global level.

Determinants of pesticides use among tomato farmers in the Bono and Ahafo regions of Ghana

Tomato production plays a crucial role in the livelihoods of farmers and agricultural households in the forest savanna transitional belt of Ghana. However, the success of tomato cultivation is hindered by the presence of insect pests and diseases, necessitating the use of agricultural inputs. This study aimed to identify the pesticides used in tomato farming, assess their World Health Organization (WHO) active ingredient hazard class, determine the precautionary behaviour associated with pesticide use by tomato farmers, and elucidate the socio-economic factors influencing pesticide usage in the Bono and Ahafo regions of Ghana. A multistage sampling procedure was employed to select 1009 respondents, who were administered a structured questionnaire. Descriptive statistics and logistic regression models were used to analyse the collected data. The results revealed that tomato farmers utilized 15 types of insecticides (e.g., lambda and chlorpyrifos ethyl based), 8 types of fungicides (e.g., mancozeb and sulphur + copper based), and 6 types of weedicides (mostly glyphosate based) on their crops. Notably, four insecticides and two fungicides types were found to be unregistered products. Lambda-cyhalothrin-based insecticides and mancozeb-based fungicides were predominantly used by the farmers. The assessed pesticides exhibited varying levels of hazard, ranging from slight to moderate. The study found that farmer training was a significant driver influencing insecticide use, while the educational level of farmers and average yield played important roles in determining fungicide use. Socio-economic factors such as being the head of the household, employing farm workers, the cultivated tomato variety, and farmer training influenced weedicide use. The type of tomato variety cultivated emerged as the primary socio-economic driver of pesticide use. The study recommended the establishment and implementation of a systematic monitoring regime for pesticide product marketing and use, with the aim of reducing the utilization of unregistered products by farmers. Implementing these measures supports sustainable tomato farming in the Bono and Ahafo regions of Ghana.

Pesticides in Ethiopian surface waters: A meta-analytic based ecological risk assessment

In most developing countries, including Ethiopia, a conspicuous gap exists in understanding risk of pesticides and establishing robust regulatory frameworks for their effective management. In this context, we present a detailed assessment of pesticide risks within Ethiopian aquatic ecosystems in at least 18 distinct surface water bodies, including 46 unique sample locations. Measured environmental concentrations (MECs; n = 388) of current-use pesticides (n = 52), sourced from existing field studies, were compared against their respective regulatory threshold levels (RTLs). The results indicated a scarcity of pesticide exposure data across the majority of Ethiopian water bodies situated within agricultural watersheds. Importantly, surface water pesticide concentrations ranged from 0.0001 to 142.66 μg/L, with a median concentration of 0.415 μg/L. The available dataset revealed that 142 out of 356 MECs (approximately 40 %) of the identified pesticides entail significant acute risks to aquatic ecosystems, with the highest RTL exceedances up to a factor of 8695. Among the pesticide use groups, insecticides exhibited the highest exceedance rate, while this was rarer for fungicides and herbicides. Furthermore, a species-specific insecticide risk assessment indicated aquatic invertebrates (54.4 %) and fishes (38.4 %) are more exposed to pesticide risks, attributable to pyrethroids and organophosphates. In conclusion, our findings demonstrate that the presently registered pesticides in Ethiopia carry elevated risks towards aquatic environments under real-world settings. This challenges the notion that pesticides approved through Ethiopian pesticide regulatory risk assessment entail minimal environmental hazards. Consequently, we advocate for the adoption of more refined risk assessment strategies, a post-registration reevaluation process, and, if deemed necessary, the imposition of bans or restrictions on highly toxic pesticides.

Self-reported health effects of pesticides among cotton farmers from the Central-West region in Burkina Faso

Pesticides are chemicals used to control pests with sometime harmful effects on human health. This paper presents results of self-reported health effects experienced by cotton farmers in the Central-West region of Burkina Faso. It was a cross-sectional survey conducted from October to December 2021 among 585 consenting conventional and organic cotton farmers. Data collected included pesticides used, they use conditions, farming practices, experienced health effects. Binary logistic regression was used to find relationships between self-reported health effects and the type of cotton produced. Results showed that all conventional cotton farmers (100%) reported using synthetic pesticides compared to organic ones who using only natural insecticides. Both conventional and organic farmers reported health effects that occurred at least once since they started using pesticides, involving skin effects (85.27% conventional, 65.52% organic), nervous (88.95% conventional, 48,71% organic), respiratory (88.10% conventional, 67.67% organic) systems. 99.72% of conventional farmers vs 46.98% of organic ones reported skin irritation following pesticide use. 69.97% of conventional vs 35.34% of organic cotton farmers reported acute signs such as severe headaches. In univariate and multivariate logistic regressions, severe headaches, dizziness, skin, and ocular effects were significantly associated with conventional farmers compared to organic ones (p < 0.05). There was a significant relationship between vomiting (p = 0.014), diarrhea (p = 0.003) and experience in synthetic pesticide use among conventional farmers. Among organic farmers, there was no significant relationship between health effects reported and experience in organic insecticides use. there was a significant relationship between severe headaches (p = 0.01), rhinitis (p = 0.006), cough (p = 0.0001), skin and ocular irritations (p = 0.007) and the frequency of synthetic insecticides use per year by conventional farmers. Study showed that conventional and organic cotton producers experience the same types of health effects. However, these health effects were significantly associated with conventional farmers compared to organic ones.

Air, Dermal, and Urinary Metabolite Levels of Backpack and Tractor Sprayers Using the Herbicide Acetochlor in Thailand

Acetochlor is a chloroacetanilide selective pre-emergent herbicide used for controlling grass and broadleaf weeds in crops. This study compared the acetochlor exposures of backpack and tractor sprayers and assessed whether dermal or air exposures were more important contributors to the overall body burden as measured by urinary metabolites. Sixty sugarcane farmers in Nakhonsawan province, Thailand participated in the study, and breathing zone air and dermal patch samples were collected during spraying. Urine samples were collected before spraying, at the end of the spraying task, and on the day after spraying. For backpack and tractor sprayers, there was no significant difference in their breathing zone air concentrations, total body dermal samples, or urinary 2-methy-6-methyaniline (EMA) concentrations on the day after spraying. In addition, although most backpack and tractor sprayers wore long pants and long sleeve shirts, they were still exposed to acetochlor, as evidenced by a significant increase in the urinary EMA from before spraying (GM = 11.5 µg/g creatinine) to after spraying (GM = 88.5 µg/g creatinine) to the next day (GM = 111.0 µg/g creatinine). Breathing zone air samples were significantly correlated with those of total body dermal patch samples and with urinary EMA concentrations after spraying. This suggests that both air and dermal exposure contribute to urinary EMA levels.

Field validated biomarker (ValidBIO) based assessment of impacts of various pollutants in water

The sensitivity of fish towards pollutants serves as an excellent tool for the analysis of water pollution. The effluents generated from various anthropogenic activities may contain heavy metals, pesticides, microplastics, and persistent organic pollutants (POPs) and ultimately find its way to aquatic environment. The enzymatic activities of fish collected from water bodies near major cities, oil spillage sites, agricultural land, and intensively industrialized areas have been reported to be significantly impacted in various field studies. These significant alterations in enzymatic activities act as a biomarker for monitoring purposes. The use of biomarkers not only helps in the identification of known and unknown pollutants and their detrimental health impacts, but also identifies the interaction between pollutants and organisms. The conventional method majorly used is physicochemical analysis, which is recognized as the backbone of the system for monitoring water quality. In physicochemical monitoring, major problems exist in assessing or predicting biological effects from chemical or physical data. Xenobiotic-induced enzymatic changes in fish may serve as an intuitive and efficient biomarker for determining contaminants in water bodies. Therefore, field validated biomarker (ValidBIO) approach needs to be integrated in water quality monitoring program for environmental health risk assessment of aquatic life impacted due to various point and non-point sources of water pollution.

Occupational and environmental pesticide exposure and associated health risks among pesticide applicators and non-applicator residents in rural Ethiopia

Intensive pesticide use increased concern about the potential acute and chronic health effects of pesticides in general and among applicators in particular. This study aims to explore occupational and environmental pesticide exposure and health risks among pesticide applicators and residents. A community-based cross-sectional study was conducted involving 1,073 individuals. We examined the health effects potentially attributable to pesticide exposure using regression to estimate prevalence ratios (PR). A higher proportion of good knowledge of pesticides [75 vs. 14%; APR = 1.542 (1.358-1.752), p < 0.001] and a higher mean score of perceived health risk of pesticide use [4.21 vs. 3.90; APR = 1.079 (1.004-1.159), p < 0.05] were observed among applicators than residents. A significantly higher proportion of applicators experienced health effects presumably related to pesticide exposure among themselves (36%) than residents (16%), and a higher proportion of them used prescribed drugs in the past 12 months [51 vs. 32%; APR = 1.140 (1.003-1.295), p < 0.05]. Skin irritation, shortness of breath, cough, and dizziness were more likely reported by applicators than residents. Perceived toxicity of currently applied pesticide products, mix pesticides without gloves, regularly maintain and wash sprayer tank after application, occurrence of an incidental splash during mixing and application, and using home-based care after experiencing a symptom presumably due to pesticide exposure were significantly associated with health effects among applicators. Use of face mask and visiting health facility when experiencing a symptom presumably due to pesticide exposure were significantly positively correlated with attending training on the health risks and use of pesticides. A substantial proportion of applicators reported improper use of preventive measures and methods of pesticide waste disposal. These observations point out that applicators can face high health risks of occupational pesticide exposure in Ethiopia. Even trained applicators pursued poor preventive practices; hence, comprehensive practice-oriented in-depth training focusing on safety precautions and proper use of personal protective equipment, and provision of adequate pesticide waste disposal means are crucial interventions.

Levels and Trophic Transfer of Selected Pesticides in the Lake Ziway Ecosystem

The levels of 30 selected pesticides and trophic biomagnification of DDT were investigated in biota samples of the Lake Ziway in the Rift valley region, Ethiopia. Carbon source and trophic position were calculated by using ¹³C and ¹⁵N stable isotopes, individually, and trophic magnification factors (TMFs) were inferred. Only DDT and its metabolites were quantified in all samples analyzed. The most prominent metabolite was p,p'-DDE with mean concentration ranging from the 0.82-33.69 ng g^-1 lipid weight. Moreover, the ratio of DDT/DDD + DDE in all the biota samples was less than 1 signifying historical DDT application. Regression of log [ΣDDT] vs TL (trophic level) among all biota species showed a significant correlation, indicating that DDTs are biomagnifying along with the food web of Lake Ziway with an estimated TMF of 2.75. The concentrations of DDTs and other organochlorine pesticides found in biota from Lake Ziway were, in general, lower than studies found in previous studies carried out in the same lake.

Pesticide residue levels in surface water, using a passive sampler and in the sediment along the littoral zone of Lake Ziway at selected sites

Diaion® HP-20 resin passive samplers deployed in water and sediment samples collected from Lake Ziway were analyzed for 30 organochlorine, organophosphorus, carboxamide, and pyrethroid pesticide residues. The samples were collected from purposely selected sampling stations in five sites on Lake Ziway. Levels of selected pesticides were determined by GC–MS/MS in all samples. p,p′DDE and boscalid residues were the only detected pesticides in sediment samples. Similarly, only metalaxyl and boscalid residues were recovered from HP-20 resins. The concentration of p,p′DDE and boscalid in sediment ranged from 0.66–7.23 and 0.1–15.26 ng g−1 dry weight respectively. The presence of p,p′DDE but no other metabolites of DDT in all sediment samples indicated that DDT residues in Ziway Lake were aged and probably originated from the weathered agricultural soils of the surrounding region. The highest level of boscalid was recorded at Site 2 (near the floriculture enterprises) both in sediment and in HP-20 resins with a mean concentration of 11.8 ng g−1 dw and 39.6 ng g−1 disk respectively. However, the concertation of metalaxyl was the highest in the HP-20 resins deployed at Site1 and Site 4 (near the intensive small-scale vegetable farm) with a mean concentration of 54.7 ng g−1 disk and 54.3 ng g−1 disk respectively. Generally, most sampling sites of p,p′DDE were found to have a moderate ecological risk based on levels specified in the sediment quality standards. Moreover, the relatively high boscalid and metalaxyl levels in HP-20 deployed in Lake Ziway would be the result of recent intensive pesticide use by floriculture enterprises and small-scale vegetable farmers in the region. A spatial variation on the accumulation of detected pesticides among the sampling sites depends on the anthropogenic activities, around the lake from the point and non-point sources. Although most of the analyzed pesticides were below the detectable limit, further studies and continued monitoring of currently used pesticide residues in the Lake are highly recommended.