Pesticide Concentrations Research Articles

Технология и качество сушено-вяленой продукции из водных биологических ресурсов поликомпонентного состава

The technology of chips production from aquatic biological resources of a polycomponent composition is considered, the formulations of minced meat and curing mixtures for their production are developed. An assess-ment of the quality of finished products was carried out. Chips were made from crushed tissues of hydrobionts. Recipes for minced meat for chips production were developed. It became possible to manufacture products with high nutritional value. Various salting mixtures were prepared for the processing the minced meat. The functional and technological properties of minced meat were improved. There were obtained products with a variety of or-ganoleptic characteristics. Modes of exposure of minced meat in salted mixtures are substantiated: the ratio of minced meat and salted mixture is 2 : 1, the duration of salting is from 60 to 90 minutes (depending on the recipe of the minced mixture at a temperature of 15 °C). The modes of drying in a convection drying chamber at a tem-perature of 55 °C, air velocity of 0.8 m/s, air humidity of 50%, for 5-6 hours are substantiated. The chemical composition of the finished product was studied: it contained of 51.3-63.7% protein, 1.5-7.2% lipids, 0.4-2.5% carbohydrates, 15.3-19.4% minerals, 16.5-23.2% water depending on the formulation. The energy value of chips was determined: it amounted to 259.40-295.2 kcal. It is substantiated that he shelf life of chips packed in bags of polymeric materials under vacuum and without it does not exceed 6 months. The product was assessed by mi-crobiological parameters and by the content of heavy metals, radionuclides, pesticides, and other chemical pollu-tants in it, which showed its compliance with the requirements and norms of the current technical regulation. The organization's standard for finished products STO 00471515-082-2020 “Dried-cured products from aquatic biological resources” was developed and approved.

Environmental exposure to organophosphate pesticides and effects on cognitive functions in elementary school children in a Middle Eastern area.

Although the fundamental reasons for cognitive function disorders have been well documented, little isknown about the impact of environmental exposures, such as pesticides, on children's cognitive function development. This study investigated the effect of exposure to organophosphate pesticides on children's cognitive function. In order to determine various factors of exposure, hair samples were collected from 114 elementary school children who lived in Boyer-Ahmad County in the province of Kohgiluyeh and Boyer-Ahmad, Iran. A detailed questionnaire was utilized to gather demographic information and exposure profile. Pesticides were detected in hair samples using a gas chromatography-mass spectrometer (GC-MS); also, cognitive function was assessed using the trail-making test (TMT), which was divided into two parts: TMT-part A and TMT-part B. Participants in the study were 10.12 ± 1.440years old on average. Children in rural areas had higher mean total pesticide concentrations (13.612 ± 22.01ng/g) than those who lived in the urban areas (1.801 ± 1.32). The results revealed that boys (46.44s and 92.37s) completed the TMT-part A and part B tests in less time than girls (54.95s and 109.82s), respectively, and showed better performance (2.14) on the cognitive function exam than girls (2.07). Diazinon and TMT-part B were positively correlated (p < 0.05). With the increasein pesticides, there was no discernible difference in cognitive function. Pesticide use throughout a child's development may affect certain cognitive function indicators. In order to assess causal relationships, group studies and case studies are required because the current research was cross-sectional in nature.

Ultra-low esfenvalerate exposure may disrupt interspecific competition

Field and mesocosm studies repeatedly show that higher tier processes reduce the predictive accuracy of toxicity evaluation and thus their value for pesticide risk assessment. Therefore, understanding the influence of ecological complexity on toxicant effects is crucial to improve realism of aquatic risk assessment. Here we investigate the influence of repeated exposure to ecologically realistic concentrations of esfenvalerate on the two similarly sensitive species Daphnia magna and Culex pipiens in a food limited and highly competitive environment. We show that significant perturbations in population development are only present at 100 ng/L (close to the EC50). In contrast, interspecific competition between species is already reduced at 0.1 ng/L (≤ 3 orders of magnitude below the acute lethal EC50). We conclude that extremely low, environmentally relevant concentrations can disrupt species interactions. This toxicant mediated alteration of competitive balances in ecological communities may be the underlying mechanism for shifts in species distribution at ultra-low pesticide concentrations. A realistic risk assessment should therefore consider these processes in order to predict potential pesticide effects on the structure of communities.

Performance of a pesticide fate model for predicting multi-year surface runoff contamination in a Mediterranean vineyard

Characterization of the risk of water contamination by pesticide runoff is an essential issue in the assessment of the environmental impact of pesticide use in agriculture. Models are valuable tools for this purpose. However, the use of pesticide runoff models implies that they can simulate the intra- and interannual variations in runoff contamination with a sufficient accuracy. In this study, we aimed to assess the performance of a modelling approach coupling Richards and convection-dispersion equations with the uniform mixing cell concept and an overland flow routine to predict the between- and within-year variability of the pesticide concentration in runoff water at the outlet of an agricultural field within a Mediterranean context. The model performance was evaluated by calibrating and validating model predictions to observed concentrations of two herbicides, diuron and glyphosate. The temporal structure of the model performance was analysed over 10 and 9 years for diuron and glyphosate, respectively. The results showed a favourable average model performance for runoff pesticide concentration prediction over approximately ten years. However, the annual performance largely varied, suggesting that at least 3 years of data are required to obtain reasonably precise runoff pesticides estimates in terms of the Nash–Sutcliffe efficiency in a Mediterranean climate. Although limited differences in the prediction performance were found between the two compounds, the within-year fluctuation of the predictions was more accurate for glyphosate than for diuron. This is interpreted by ageing effects that affect diuron sorption but not glyphosate sorption. Furthermore, the study results indicated that the parameters critical to precise estimation depend on the simulation objectives. The main parameter values to be determined include the pesticide half-life time when estimating chronic exposure to pesticide runoff and the sorption coefficient and mixing depth when predicting the maximum observed concentration during a given season.

Using machine learning to predict the efficiency of biochar in pesticide remediation

Pesticides have remarkably contributed to protecting crop production and increase food production. Despite the improved food availability, the unavoidable ubiquity of pesticides in the aqueous media has significantly threatened human microbiomes and biodiversity. The use of biochar to remediate pesticides in soil water offers a sustainable waste management option for agriculture. The optimal conditions for efficient pesticide treatment via biochar are aqueous-matrix specific and differ amongst studies. Here, we use a literature database on biochar applications for aqueous environments contaminated with pesticides and employ ensemble machine learning models (i.e., CatBoost, LightGBM, and RF) to predict the adsorption behavior of pesticides. The results reveal that the textural properties of biochar, pesticide concentration, and dosage were the significant parameters affecting pesticide removal from water. The data-driven modeling intervention offers an empirical perspective toward the balanced design and optimized usage of biochar for capturing emerging micro-pollutants from water in agricultural systems.

Method optimisation for large scope pesticide multiresidue analysis in bee pollen: A pilot monitoring study

Pesticide contamination in emerging foods and supplements is currently a topic of great interest. This study focused on the evaluation of pesticide residues in commercial bee pollen samples to evaluate the risk associated with their consumption. To this end, an automated clean-up method for the pesticide extracts of bee pollen was developed. An LC-MS/MS and a GC-MS/MS method were validated for the analysis of 353 pesticides in 80 bee pollen samples purchased from different countries. The results showed the presence of 77 different pesticide residues in bee pollen, including plant protection chemicals and veterinary treatments. 85 % of the samples were contaminated with pesticides and no relevant differences were found between conventional and organic samples. Pesticide concentrations exceeding the imposed MRL were found in 40 % of the samples, but the risk assessment showed that consumers are not exposed to an unacceptable risk when consuming the evaluated bee pollen.

Estimating the Jordanian population dietary exposure to pesticides residues: An exploratory deterministic approach.

The Jordanian population's exposure to pesticides may have never been estimated. This study uses a deterministic approach as a screening method to determine the population's likelihood of daily dietary exposure to pesticide residues and identify pesticides that require further investigation. We investigated the data from surveillance programs to assess pesticide contamination in food. We also obtained data about the population's estimated consumption of different food items. The daily exposure to pesticide residues through food was estimated with two scenarios (Lu et al., 2006): the lower bound (LB) scenario and (Luo and Zhang, 2009) the upper bound (UB) scenario. The data provided the concentration of pesticides in 8085 food samples. In 15.7% of the samples, 134 pesticides were identified. The levels of quantified pesticides exceeded MRL in 41.7% of the samples. Under the LB, mean estimated daily exposures were higher than the acceptable daily intakes (ADIs) for 27 investigated residues. Using the UB scenario, which tends to overestimate exposure, the mean estimated daily exposures were above the ADIs for 111 residues. The study concludes that the population's dietary exposure to pesticide residues is noteworthy and provides a list of pesticides that could be consumed at levels higher than the relevant ADI value and thus require further assessment.

Quantification, distribution and cancer risk assessment of pesticides in mango orchards of Kerala, India

ABSTRACT Muthalamada in the Western Ghats has been a prominent mango-cultivating region of Asia for the last three decades. In the present study, soil samples from Muthalamada mango orchards were analysed for pesticide contents and estimated associated cancer risk indices. Sixteen pesticides, including organochlorines, organophosphates, synthetic pyrethroids, and carbamates were detected in the region. The concentration of chlorpyrifos (2.05–720.27 mg/kg) was the highest level reported from any agroecosystem in India. Community health risk assessment indicates high carcinogenic risk and greater susceptibility in children. The study demonstrates the need for immediate interventions to reduce the ecological and human cancer risks in the mango orchards.

ORGANOCHLORINE PESTICIDES POLLUTION OF THE BOTTOM SEDIMENTS OF NAKHODKA BAY AND PARTIZANSKAYA RIVER

Link for citation: Mazlova E.A., Blinovskaya Ya.Yu., Sokolova L.I., Tursunova G.Sh. Organochlorine pesticides pollution of the bottom sediments of Nakhodka bay and Partizanskaya river. Bulletin of the Tomsk Polytechnic University. Geo Аssets Engineering, 2023, vol. 334, no. 9, рр. 25-35. In Rus. Relevance. The new data on the organochlorine pesticides pollution of the bottom sediments of Nakhodka bay and Partizanskaya river were obtained in 2020–2021. The objective of the article is to report the organochlorine pesticides pollution level of the bottom sediments and to define the possible sources of organochlorine pesticides in the marine environment. Techniques: sample collection of bottom sediments, Gas Chromatography Mass Spectrometry analysis of samples, Gas-liquid Chromatography method with electronic capture detector, statistical processing, assessment of the organochlorine pesticides contamination of sediments. Results. The new data were obtained on the organochlorine pesticides concentrations in Nakhodka bay in 2020–2021. The previous data on the studied area are described. The concentration of HCH pesticides (α- , β- and γ-HCH), DDT and its metabolites was analyzed. It was found that the concentration of α- , β- HCCH and DDT in bottom sediments increased in 2021.To determine the quality of bottom sediments, the average annual values of organochlorine pesticides concentrations in the bottom sediments gathered during the field works were compared with the quality guidelines. There are no approved quality guidelines for maximum permissible concentrations of pollutants in bottom sediments in the Russian Federation. For this reason, we used the quality guidelines applied in foreign countries («Dutch sheets» (Neue Niederlandische Liste. NNL) and Canadian quality standards for marine and estuarine bottom sediments (Canadian Sediment Quality Guidelines, CSQGs). Possible sources of organochlorine pesticides in the marine environment were analyzed. The results of this work showed that despite the ban on the use of these substances, these pesticides are included in the multiple compounds used in different industries and continue to enter and accumulate in the marine environment.

Development of an ice cream recipe using mare's milk and polysaccharides

The use of mare's milk in mass nutrition is due to its medicinal and dietary properties. The ice cream recipe created as a result of research has included mare's milk, sugar, vanillin, pasteurized chicken yolks, and polysaccharides. The test samples have contained polysaccharides from 0.1 to 1.0 %: guarana; locust bean gum; gum arabic; xanthan gum; apple pectin; bamboo fibers; apple fibers. Based on the organoleptic evaluation, the best samples of ice cream with xanthan gum at the concentration of 0.1 % and bamboo fibers at the concentration of 0.4 % have been selected. In the course of studying the physicochemical and microbiological parameters of a new dairy product, it has been found that ice cream with the addition of polysaccharides in terms of the content of toxic elements, pesticides and radionuclides meets the food safety standards. The developed ice cream can be recommended to all segments of the population as a source of calcium, phosphorus and iron. The results of the analysis of physicochemical and microbiological parameters contribute to the formation of a theoretical basis for studying the properties of polysaccharides – xanthan gum and bamboo fibers. The use of these polysaccharides in mare's milk ice cream opens up prospects for their further use in the food industry.

Cottonseed Glyceride and Hydrogenated Cottonseed Glyceride.

The Expert Panel for Cosmetic Ingredient Safety reviewed newly available studies since their original assessment in 2001, along with updated information regarding product types and concentrations of use, and confirmed that Cottonseed Glyceride and Hydrogenated Cottonseed Glyceride are safe as cosmetic ingredients in the practices of use and concentration as described in this report, provided that established and imposed limits on gossypol, heavy metals, and pesticide concentrations are not exceeded.

A systematic review on the current situation of emerging pollutants in Mexico: A perspective on policies, regulation, detection, and elimination in water and wastewater

Emerging pollutants (EPs) emerged as a group of new compounds whose presence in the environment has been widely detected in Mexico. In this country, different concentrations of pharmaceutical compounds, pesticides, dyes, and microplastics have been reported, which vary depending on the region and the analyzed matrix (i.e., wastewater, surface water, groundwater). The evidence of the EPs' presence focuses on the detection of them, but there is a gap in information regarding is biomonitoring and their effects in health in Mexico. The presence of these pollutants in the country associated with lack of proper regulations in the discharge and disposal of EPs. Therefore, this review aims to provide a comprehensive view of the current environmental status, policies, and frameworks regarding Mexico's situation. The review also highlights the lack of information about biomonitoring since EPs are present in water even after their treatment, leading to a critical situation, which is high exposure to humans and animals. Although, technologies to efficiently eliminate EPs are available, their application has been reported only at a laboratory scale thus far. Here, an overview of health and environmental impacts and a summary of the research works reported in Mexico from 2014 to 2023 were presented. This review concludes with a concrete point of view and perspective on the status of the EPs' research in Mexico as an alert for government entities about the necessity of measures to control the EPs disposal and treatment.

The Consequences and Challenges Associated with Amphibian Toxicology Regarding Pesticides

Amphibian populations worldwide are experiencing a decline due to a combination of abiotic and biotic factors. Climate change, habitat loss, pollution, and disease outbreaks all contribute to this decline. Many amphibian species are listed as vulnerable or near extinct (43% of the species described nowadays) on the IUCN Red List. Anthropogenic contaminants, particularly pesticides, can be incredibly harmful to these populations. Pesticides can come from different sources, in particular from agriculture. Contamination of animals can occur through ingestion of contaminated feed, air, drift, secondary poisoning, spillage into local water bodies, contaminated plants and sediments, or groundwater contamination. Higher concentrations of pesticides in the environment can have acute toxic effects with high mortality rates, or long-term exposure can lead to reproductive abnormalities, infertility, and malformations. Several papers have implicated pesticides in the amphibian population decline. The primary objective of the research was to establish a link between the use of pesticides and the decline of amphibian populations, focusing on documented cases in the wild where these chemicals have been identified as the primary cause of mortality among these species and assessing their broader ecological impacts. Additionally, the study aimed to highlight the main challenges encountered in conducting ecotoxicological research on amphibians and to explore potential avenues for future research and mitigation efforts.

Microbial Community Response to Various Types of Exogenous Organic Matter Applied to Soil.

Recycling of solid biowaste and manure would reduce the dependence of agriculture on synthetic products. Most of the available studies on the effects of exogenous organic matter (EOM) application to soil were focused on nutrients and crop yield, with much less attention to microbiological processes in soil, especially using modern molecular methods. The aim of this study was to evaluate the effects of various types of manure, sewage sludge and bottom sediment on the biochemical activity and biodiversity of soil and plant yield in a pot experiment. The soil was treated with a range of EOM types: six types of manure (cattle, pig, goat, poultry, rabbit and horse manure; two bottom sediments (from urban and rural systems); and two types of municipal sewage sludge. All EOMs stimulated dehydrogenases activity at a rate of 20 t ha-1. Alkaline phosphatase was mostly stimulated by poultry manure and one of the sludges. In general, the two-fold greater rate of EOMs did not further accelerate the soil enzymes. The functional diversity of the soil microbiome was stimulated the most by cattle and goat manure. EOMs produce a shift in distribution of the most abundant bacterial phyla and additionally introduce exogenous bacterial genera to soil. Poultry and horse manure introduced the greatest number of new genera that were able to survive the strong competition in soil. EOMs differentiated plant growth in our study, which was correlated to the rate of nitrate release to soil. The detailed impacts of particular amendments were EOM-specific, but in general, no harm for microbial parameters was observed for manure and sludge application, regardless of their type. There was also no proof that the PAH and pesticide contents measured in manure or sludge had any effect on microbial activity and diversity.

Enhancement of photocatalytic activity of Ba-doped CoO for degradation of Emamectin benzoate in aqueous solution.

The present study was focused on the preparation of cobalt oxide (CoO) and barium-doped cobalt oxide (Ba-doped CoO) by following the co-precipitation method for the degradation of Emamectin benzoate pesticide in the aqueous medium. The prepared catalysts were characterized using SEM, EDX, and XRD to confirm the formation of catalysts and to observe the variation in the composition of catalysts during the degradation study. It can be suggested from the results of SEM, EDX, XRD, and FTIR analyses that Ba atom has successfully incorporated in the crystalline structure of CoO. The degradation of Emamectin benzoate pesticide was studied under the influence of different factors like solution pH, the dose of catalyst, contact time, temperature, and initial concentration of pesticide. It was observed that solution pH affects the degradation of the pesticide, and maximum degradation (23% and 54%) was found at pH 5.0 and 6.0 using CoO and Ba-doped CoO, respectively. The degradation of pesticides was found to be increased continuously (27-35% in case of CoO while 47-58% in case Ba-doped CoO) with the time of contact. However, the degradation was found to be decreased (23-3% in case of CoO while 47-44% in case Ba-doped CoO) with an increase in temperature. Likewise, in the beginning, degradation was observed to be increased up to some extent with the dose of catalyst and initial concentration of pesticide but started to decrease with further augmentation in the dose of catalyst and initial concentration of pesticide. It may be concluded from this study that doping of Ba considerably enhanced the photocatalytic ability of CoO for Emamectin benzoate pesticide.

A Fluorescent Benzothiazole Probe for the Detection of Carboxylesterase and Carbamate Pesticides

AbstractA benzothiazole fluorescent probe (probe 1) was developed for the determination of carboxylesterase and carbamate pesticides. The probe used benzothiazole as the fluorescent group and chlorophenyl acetate as the recognition group. The recognition mechanism of probe 1 for carboxylesterase was based on the enzymatic hydrolysis of chlorophenyl acetate by carboxylesterase. The solution of probe 1 gradually changed from light blue to dark blue as the concentration of carbamate pesticide increased. Probe 1 could detect the concentration of carbamate pesticide based on the linear functional relationship between the R/B*G (red, blue, green) value of the probe 1 solution photo and the concentration of carbaryl without professional personnel and equipment. Additionally, probe 1 was successfully used to detect the concentration of carbaryl in actual samples based on the curve function relationship between the fluorescence intensity of probe 1 at 434 nm and the concentration of carbaryl.

Time-dependent mortality and behavioral response of Odontotermes obesus (Blattodea: Termitidae) against different dose rates of pesticides for sustainable forest management

Termites have become a global concern, and their effective management has remained a challenge since time immemorial. Certain microbial and botanical agents have been used for their management, but their efficacy has been compromised, particularly in field conditions. Hence, the current study was designed to check the efficacy of low doses of different pesticides, such as chlorpyrifos, fipronil, bifenthrin, and chlorantraniliprole, against mortality and behavioral responses of Odontotermes obesus at two different temperatures (16 ± 1 and 26 ± 1°C). The discrete behavioral symptoms included intoxication, ataxia, moribundity, and death. Laboratory-maintained termite workers were exposed to different concentrations of pesticides through a filter paper bioassay. All tested pesticides and their concentrations differed significantly regarding their lethal time (LT50) values compared to the mortality of termite workers. Moreover, the LT50 values of pesticides gradually decreased with increased pesticidal concentrations. Temperature also had a significant effect on the efficacy of tested pesticides as all pesticides showed better results at higher temperatures. At both tested temperatures, chlorantraniliprole (5 ppm) proved to be the most effective pesticide against termite workers. Similarly, the behavioral symptoms also varied depending on pesticides and their administered concentrations and existed for a relatively longer time span at lower temperatures. In most cases, the order of responses was moribundity, followed by intoxication and ataxia. Moribundity and intoxication were the most frequently observed symptoms for chlorpyriphos and bifenthrin-treated termite workers. In the case of fipronil, intoxication was the most pronounced symptom. Similarly, the maximum value of ataxia was recorded in the case of chlorantraniliprole. However, moribund symptoms lasted longer in all tested concentrations of chlorantraniliprole, followed by ataxia and intoxication. The overall order of toxicity was chlorantraniliprole &amp;gt; bifenthrin &amp;gt; fipronil &amp;gt; chlorpyrifos. These pesticides, at their low doses, did not exhibit any repellent action and were not detected by the foraging termite workers. Moreover, their slow action mechanism makes them a suitable candidate for infecting whole colonies away from treated surfaces. Therefore, these pesticides can be successfully incorporated into different integrated termite management programs to keep the plantation free from threatening underground pests.

Risk Assessment of Residual Pesticides of Phaseolus vulgaris L. Consumed in Port Harcourt, Rivers State, Nigeria

Pesticides are important and necessary in reducing the loss caused by insect infestation on grains. However, its toxicity and persistence in the environment is of health concern. Beans (Phaseolus vulgaris L.) preserved with insecticide are considered to be good for consumption if its content of insecticide is not higher than the maximum residue limits (MRLs). The aim of this research was to quantify the residue of pesticide in four beans samples and determine the health risk associated with consuming these foods by residents of Port Harcourt, Rivers State, Nigeria. Pesticides content of beans samples were analyzed using Gas Chromatography (GC). The results of the study showed the presence of 17 different pesticide residues in all samples of beans. 2,4-Dichlorophenoxyacetic acid (2,4-D) and 2,2-dichlorovinyl dimethyl phosphate (DDVP) were detected in all samples of beans and at levels above European Union’s (EU's) MRL except in iron beans samples. Glyphosate was detected in all the samples at concentration above EU’s MRL. However, pesticides in Raw iron beans such as carbofuran (0.43±0.03 mg/kg), Endosulphan (0.18±0.01 mg/kg), HCB (0.62±0.10 mg/kg) Profenos (0.55±0.04 mg/kg) and t-nonachlor (0.32±0.00 mg/kg) decreased significantly to 0.23±0.10 mg/kg, 0.09±0.01 mg/kg, 0.31±0.01 mg/kg, 0.38±0.01 mg/kg, and 0.22±0.00 mg/kg respectively in Parboiled iron beans. This indicates reduced Health Risk Index (HRI) to pesticides of parboiled beans samples. Similar results were also recorded in other raw and parboiled beans varieties studied. This calls for the attention of regulatory agencies in foods and food products to effectively monitor the use and application of pesticides on foodstuff and also encourage parboiling before cooking to eat.

Incorporating the benefits of vegetative filter strips into risk assessment and risk management of pesticides.

The pesticide registration process in North America, including the USA and Canada, involves conducting a risk assessment based on relatively conservative modeling to predict pesticide concentrations in receiving waterbodies. The modeling framework does not consider some commonly adopted best management practices that can reduce the amount of pesticide that may reach a waterbody, such as vegetative filter strips (VFS). Currently, VFS are being used by growers as an effective way to reduce off-site movement of pesticides, and they are being required or recommended on pesticide labels as a mitigation measure. Given the regulatory need, a pair of multistakeholder workshops were held in Raleigh, North Carolina, to discuss how to incorporate VFS into pesticide risk assessment and risk management procedures within the North American regulatory framework. Because the risk assessment process depends heavily on modeling, one key question was how to quantitatively incorporate VFS into the existing modeling approach. Key outcomes from the workshops include the following: VFS have proven effective in reducing pesticide runoff to surface waterbodies when properly located, designed, implemented, and maintained; Vegetative Filter Strip Modeling System (VFSMOD), a science-based and widely validated mechanistic model, is suitable for further vetting as a quantitative simulation approach to pesticide mitigation with VFS in current regulatory settings; and VFSMOD parametrization rules need to be developed for the North American aquatic exposure assessment. Integr Environ Assess Manag 2024;20:454-464. © 2023 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

Photocatalytic degradation and removal of type II pyrethroid pesticide (lambda-cyhalothrin) residue from wastewater using nanoceria for agricultural runoff application

Synthetic chemical pesticides' nature, mode of action, and persistence have brought about debates regarding whether the end justifies the means. Lambda-cyhalothrin is an important insecticide for farmers and households, with great accessibility and excellent action against pests and disease-carrying insects. Like other pyrethroid pesticides, Lambda-cyhalothrin targets the nervous system of insects or pests. However, its fate in the environment, especially in water and living systems, has made it crucial to explore methods of treating or degrading its residues in the environment. The present study aimed to develop a suitable method for the photocatalytic degradation and removal of Lambda-cyhalothrin (LCY) from wastewater and agricultural runoff. The nanoceria were used under natural solar irradiation without applying any scavenger chemical or buffer. This was synthesized using a simple co-precipitation method using cerium nitrate hexahydrate as a precursor. The synthesized nanoceria were characterized using X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS), Fourier Transform Infrared spectroscopy (FTIR) and particle size analysis. The average size of the particle was 27 nm. The photocatalytic degradation was conducted in batches with various pesticide concentrations exposed to different amounts of nanoceria. The initial and final concentrations of the LCY at each level were determined using Shimadzu UV spectroscopy. At optimum conditions, nanoceria was found to degrade and remove more than 63% of the initial pesticide concentration. This method can be suitable for degrading and removing pesticide residue from agricultural runoff (at source) and industrial effluents from synthetic pesticide industries.