Abebaw Abaineh

This study aimed to analyze pesticide residues in the sediments and soils of Fogera District, Ethiopia, to evaluate the risks posed to organisms that dwell in these environments. A total of 7 sediments from rivers, canals and ponds, and 13 soil samples from irrigated farmlands were collected from April to June 2023 using a cross-sectional study design. The samples were collected from 0-8 cm depth in both sediments and soils using scoops and spoons. Analytes were prepared following the buffered procedures, extracted following the Quick, Effective, Cheap, Rugged, and Safe (QuEChERS) method and extracts were analyzed using the triple quad gas chromatography-mass spectrometry technique. Twenty-seven pesticides were identified and quantified both in the sediment and soil samples. More than 85% of the pesticide residues in the sediment and soil samples were organochlorines and organophosphates. The concentrations of the organochlorine and organophosphate pesticides in sediments ranged from ND to 9.94 µg/kg and ND to 12.12 µg/kg, respectively. Similarly, the concentration of the organochlorine and organophosphate pesticides in the soil samples ranged from ND to 13.69 µg/kg and ND to 10.70 µg/kg, respectively. Though the mean concentration difference between the pesticide residues in the sediment and soil samples was insignificant (t (18) = -0.871, p = 0.395), the risks of pesticide residues in sediments to aquatic biota were much higher than those in the soil biota. Of the 27 pesticides detected in sediments, 24 of them pose a higher risk and 1 moderate risk to aquatic biota. The risk quotients of Endrin aldehyde and Endrin ketone in sediments were not calculated due to the lack of endpoint concentrations. In a general case scenario, the risk quotients of the pesticides ranged from 0.80 (Para-methyl) to 21086.43 (Deltamethrin) in sediments and from 0.001 (Malathion) to 17.689 (Profenofos) in soils. The pesticide residues in sediments and soils might pose adverse effects on the biota of aquatic and terrestrial ecosystems. Therefore, a transparent pesticide supply chain and deploying qualified experts to monitor and inspect the types of pesticides in use and the pesticide application practices, detail studies on the level of toxicities of the commonly applied pesticides to the biota of aquatic and terrestrial ecosystems, and enforcing the pesticide laws are required to reduce the adverse effects of pesticides.

Pesticides have posed health risks to consumers and the ecosystems in different parts of the world, including Ethiopia, and researchers recommend continual assessments of pesticide residues in food items and ecosystems to know the level of risks. This study aimed to quantify the pesticide residues in samples of cabbage and fish and their risks to humans and the ecosystems. The cabbage samples were collected from April to May 2023 from 3 market centers, and the fish samples were collected in June 2023 from two fish ponds of Fogera District of Ethiopia using appropriate sampling procedures, extracted using the modified QuEChERS methods, and analyzed using a triple quadrupole GC/MS technique to quantify the pesticide residues and level the risks to humans and the ecosystems. The findings of the present study confirmed that all the samples of cabbage and fish were contaminated with pesticide residues. More than 44% and 37% of pesticide residues detected in both cabbage and fish samples were organochlorine and organophosphate pesticides, respectively. Furthermore, 92.86% of the pesticide residues and 96.43% of the maximum pesticide residues in cabbage exceeded the MRL and the TQ set by the Codex Alimentarius Commission. The sum total hazard indices of the pesticide residues in the cabbage (22.320) and fish (43.071) were much higher than the threshold value. Though Fogera District is a potential area for fish production in ponds, agricultural pesticides are a threat to the sector. Establishing an efficient system of monitoring for the pesticide supply chain and application procedures, choosing the appropriate pesticide types, timing in spraying, and establishing pesticide-free buffer zones are crucial steps in mitigating the negative effects of pesticides in the area.

Despite their significance in food security, pesticides have the potential to seriously harm both the environment and human health. It may lower the rates of egg hatching, offspring growth, vision, illness resistance, predator avoidance, and overall population survival. Nevertheless, over 75% of Ethiopian farmers lack the literacy to read pesticide labels and comprehend the consequences of pesticide residues on the environment. Pesticides are mixed and applied in close proximity to bodies of water, including sources of drinkable water. Farmers in the country overuse and misuse the pesticides without worrying about its negative effects. Ethiopia failed to adequately enforce its environmental protection laws to reduce the harmful effects of pesticide residues. The aim of this review is to summarize the trends of pesticide use, the effects of pesticide residues on aquatic ecosystems, the pesticide application practices, and the level of enforcement of pesticide laws in the country. The literature search was done using different search engines. Disagreement among policies, absence of liability for overlooking duties, negligence of the pesticide effects on human health and the environment, and a strong commitment to short-term economic growth are reasons for ineffective law enforcement. Regular supply chain inspections, management of pesticide use, and widespread awareness campaigns are crucial steps to reduce the harmful effects of pesticides on the environment, living things, and humans. Establishing pesticide-free buffer zones for water bodies, replacing the contradictory sectorial policies with integrated development policy, and executing the policy objectives are also crucial steps that need to be taken.

Pesticides are chemicals used to control different types of pests. Though pesticides played a role in improving the quantity and quality of production, they have been threatening ecosystems and posed effects on humans in different parts of the world. Unfortunately, there were no studies made about the effects of pesticide residues on ecosystems and consumers in the Fogera District of Amhara Region, Ethiopia. Hence, the main objective of this study was to understand the knowledge, attitude, and practices of respondents about the effects of pesticide residues on ecosystems and consumers. A cross-sectional survey complemented by focus group discussions and field observations was used to gather the required data for the study. The close-ended data were analyzed using descriptive statistics, logistic regressions, and independent t-test, and data from open-ended questions were grouped and summarized based on their similarities. The findings of the study confirmed that there was significant knowledge, attitude, and practices difference between farmers and consumers about the effects of pesticide residues on ecosystems and humans. Farmers used highly toxic pesticides to control pests and improve the glossiness of vegetables and khat. Though they didn’t use the sprayed vegetables for their home consumption, some of the farmers deliberately supplied pesticide-sprayed vegetables without worrying about the negative effects of the pesticides on the consumers. There were also fishing practices from rivers after intoxicating the fish using the pesticide sprayed feed. This, in turn, might poison individuals who consume the fish. In general, pesticide application practices and consumption of pesticide-sprayed foodstuffs and surface water might pose serious health risks to ecosystems and humans. To minimize the negative effects of pesticides, rigorous awareness-raising on the effects and management of pesticides, enforcement of laws, delineation of the pesticide free buffer zone for waters, the establishment of a clear pesticide supply chain to the end users, ecosystem assessment and food safety monitoring schemes are highly required.