Pesticide residues in food of plant origin from Southeast Asia – A Nordic project

Natural product osthole can significantly disrupt cell wall integrity and dynamic balance of Fusarium oxysporum

Dendrobium officinale Kimura et Migo is a traditional Chinese herbal medicinal plant. However, the frequent occurrence of soft rot disease (SRD) is one of the most harmful diseases in D. officinale production in recent years, which can seriously affect its yield and quality. In this study, the major pathogenic fungus (SR-1) was isolated from D. officinale with typical symptoms of SRD, and was identified as Fusarium oxysporum through morphological and molecular identification. The biological activities of five natural products were determined against F. oxysporum using a mycelial growth inhibition assay. The results showed that osthole had the highest antifungal activity against F. oxysporum, with an EC50 value of 6.40 mg/L. Scanning electron microscopy (SEM) showed that osthole caused F. oxysporum mycelia to shrink and deform. Transmission electron microscopy (TEM) showed that the organelles were blurred and the cell wall was thickened in the presence of osthole. The sensitivity of F. oxysporum to calcofluor white (CFW) staining was significantly enhanced by osthole. Relative conductivity measurements and propidium iodide (PI) observation revealed that osthole had no significant effect on the cell membrane. Further experiments showed that the activity of chitinase and β-1,3-glucanase were decreased, and expression levels of chitinase and β-1,3-glucanase related genes were significantly down-regulated after treatment with osthole. In conclusion, osthole disrupted the cell wall integrity and dynamic balance of F. oxysporum, thereby inhibiting normal mycelial growth.

Dietary exposure risk assessment of pyrethroids in fruits and vegetables: a national scale investigation

The pyrethroids (PYRs) were extensively used to increase agriculture outputs. However, the cumulative exposures of PYRs would bring about potential risks through food intake. It is an urgent requirement to explore the cumulative exposures on the fruits and vegetables. In this study, a total of 1720 samples incorporating eight primary fruits and vegetables collected around China were investigated to assess the health risk for adults and children from eight PYRs. The relative potency factor (RPF) method was employed to reveal both chronic and acute cumulative exposure. As a result, the hazard index (HI) were 0.004 ~ 0.200% and 11.85 ~ 99.19% for chronic and acute cumulative dietary exposure, respectively. The national wide investigation indicated the cumulative assessments were not hazardous. Besides, the acute intake of pear, grape, and lettuce should be paid on more attention, particularly. This study provides compelling evidence to develop relative policy and regulation to improve the food quality and safety.

Impact of a megacity on the water quality of a tropical estuary assessed by a combination of chemical analysis and in-vitro bioassays

Tropical estuaries are threatened by rapid urbanization, which leads to the spread of thousands of micropollutants and poses an environmental risk to such sensitive aqueous ecosystems. In the present study, a combination of chemical and bioanalytical water characterization was applied to investigate the impact of Ho Chi Minh megacity (HCMC, 9.2 million inhabitants in 2021) on the Saigon River and its estuary and provide a comprehensive water quality assessment. Water samples were collected along a 140-km stretch integrating the river-estuary continuum from upstream HCMC down to the estuary mouth in the East Sea. Additional water samples were collected at the mouth of the four main canals of the city center. Chemical analysis was performed targeting up to 217 micropollutants (pharmaceuticals, plasticizers, PFASs, flame retardants, hormones, pesticides). Bioanalysis was performed using six in-vitro bioassays for hormone receptor-mediated effects, xenobiotic metabolism pathways and oxidative stress response, respectively, all accompanied by cytotoxicity measurement. A total of 120 micropollutants were detected and displayed high variability along the river continuum with total concentration ranging from 0.25 to 78 μg L^-1. Among them, 59 micropollutants were ubiquitous (detection frequency ≥ 80 %). An attenuation was observed in concentration and effect profiles towards the estuary. The urban canals were identified as major sources of micropollutants and bioactivity to the river, and one canal (Bến Nghé) exceeded the effect-based trigger values derived for estrogenicity and xenobiotic metabolism. Iceberg modelling apportioned the contribution of the quantified and the unknown chemicals to the measured effects. Diuron, metolachlor, chlorpyrifos, daidzein, genistein, climbazole, mebendazole and telmisartan were identified as main risk drivers of the oxidative stress response and xenobiotic metabolism pathway activation. Our study reinforced the need for improved wastewater management and deeper evaluations of the occurrence and fate of micropollutants in urbanized tropical estuarine environments.

Magnetic dispersive solid-phase extraction of some pesticides from fruit juices using monodisperse nanosorbent combined with dispersive liquid-liquid micro-extraction

In this study, the new synthesized magnetic nanoparticles based on amorphous carbon have been used as a sorbent in magnetic dispersive solid-phase extraction prior to dispersive liquid-liquid micro-extraction. The developed method was applied for analysis of ten pesticides from different fruit juice samples by gas chromatography-flame ionization detection. In this work, a few mg of the sorbent is added into an aqueous solution containing the analytes. Adsorption and desorption of the compounds of interest are accelerated by vortexing and sonication, respectively. To achieve high enrichment factors, a suitable organic solvent (iso-propanol) is used to elute the target analytes from the nanosorbent. The obtained iso-propanol is phased and 1,1,2-trichloroethane are employed as the disperser and extraction solvents, respectively, in the following micro-extraction procedure. The synthesized magnetic nanoparticles were characterized by scanning electron microscope, X-ray diffraction, vibrating sample magnetometer, and Fourier-transform infrared spectrophotometer. To achieve the high extraction efficiency and optimum conditions, all parameters that could affect the extraction yield were investigated. Under optimum conditions, the method had broad linear ranges with a proper linearity (r² ≥ 0.9987). Limits of detection and quantification for analysis of the selected pesticides were found in the ranges of 0.5-1.0 and 1.7-3.3 µg L^-1, respectively. High enrichment factors and extraction recoveries were obtained in the ranges of 321-438 and 64-88%, respectively. To evaluate repeatability of the method, it was performed on two sets of standard solutions at the concentrations of 10 and 50 µg L^-1 (each analyte). Relative standard deviations varied in the ranges of 2-6% and 4-7% for intra- (n = 6) and inter-day (n = 5) precisions, respectively.

Immunohistochemical distribution of Bcl-2 and p53 apoptotic markers in acetamiprid-induced nephrotoxicity

Pesticides, which adversely affect the critical metabolic processes of organisms, disrupt the physiological balance by specifically targeting enzymes and may lead to such consequences that may lead to death. It provides benefits in agricultural activities. The p53 protein antagonizes bcl-2, an anti-apoptotic protein character, and induces apoptosis by causing mitochondrial membrane permeability. This study aims to show the effect of acetamiprid, which is an insecticide from the neonicotinoid class, on bcl-2 and p53 immunoreactivity, which has an important place in the apoptotic mechanism in kidney tissue. A total of four groups including control and three experimental groups (the acetamiprid was administered 5, 10, and 15 mg kg−1) were formed in the study. After acetamiprid was administered via gavage for 14 days, the kidney tissues taken from the mice, which were sacrificed by cervical dislocation, were fixed in 10% formaldehyde solution for histological and immunohistochemical analyses, and as a result of routine tissue follow-up, the sections were blocked in paraffin and stained with haematoxylin–eosin and immunostaining. The histopathological examinations revealed that while the kidney tissue had a normal structure in the control group, degeneration in the distal and proximal tubules, glomerular degeneration, increase in the capsular area, glomerular atrophy, and haemorrhage were determined in the acetamiprid groups at increasing severity and frequency depending on the dose of the applied substance. In the kidney tissue, Bcl-2 and p53 immunoreactivity was observed in glomerular cells, sinusoidal epithelium, and proximal and distal tubule cells. The acetamiprid caused pathological changes in the kidneys in the dose range used. This effect also affects the expression of bcl-2 and p53 genes, which are biomarkers in the apoptotic mechanism. As acetamiprid accumulates in tissues, it increases the expression of p53 from cell death receptors, while suppressing the anti-apoptotic bcl-2 expression.

Risk assessment of carbofuran residues in fruits and vegetables at the Chinese market: A 7-year survey

The United Nations designated 2021 as the International Year of Fruits and Vegetables (IYFV), with the goal of educating populations regarding the role of such produce in nutrition, food safety, and overall health. Carbofuran is a highly toxic insecticide and nematocide, and its use to treat fruit trees, vegetables, tea, and medicinal herbs is thus prohibited. However, carbofuran residues are still detectable via LC-Q-TOF/MS in fruit and vegetable samples collected from 138 sites in 31 regions. In the present study, carbofuran levels were sampled at 1388 sampling sites in 31 regions (provinces, autonomous regions, and municipalities) not including Hong Kong, Macao, or Taiwan. In total, over 36,000 samples (including 12,547 samples of 41 kinds of fruits and 23,785 samples of 83 kinds of vegetables) were randomly collected from supermarkets and farmer's markets. These data were used to conduct a risk assessment pertaining to dietary carbofuran exposure through the consumption of fruits and vegetables. In total, carbofuran residues were detectable in 2.0% of fruits and 2.3% of vegetables. Risk assessments indicated that the intake of fruits and vegetables harboring carbofuran residues did not pose a chronic health risk. However, peaches, grapes, sweet peppers, celery, Chinese chives, leaf lettuce, spinach, small rape, mustard greens, cucumbers, watermelons, Chinese wolfberry leaves, wax gourds, snap beans, bitter melons, green Chinese vegetables, lettuce, shallot, cowpeas, eggplants, tomatoes, tangerines, summer squash, oranges, lemons, Chinese cabbage, peppers, and strawberries were associated with an unacceptable acute risk to both children and adults. Moreover, crown daisies, nectarines, citrus fruits, pitayas, melons, kale, cabbages, milk Chinese cabbage, carrots, and melons were associated with an unacceptable acute risk to children. Substantial acute risk to children and adults was observed for fruits and vegetables from surveyed regions other than Inner Mongolia, Yunnan, Liaoning, Fujian, Xinjiang, and Hubei. Together, these data provide a foundation for future research aimed at the management of carbofuran residues in fruits and vegetables in an effort to better protect consumer health.

Multiresidue analysis and dietary risk assessment of pesticides in eight minor vegetables from Guizhou, China

Several minor vegetables are widely employed as hot pot dishes and condiments in Southwest China. To gain insight into pesticide exposure risk via the intake of minor vegetables, vegetable samples (400) obtained from different farms in Guizhou were subjected to multiresidue analyses. Gas chromatography-tandem mass spectrometry and high performance liquid chromatography-tandem mass spectrometry were developed to detect and quantify 97 pesticide residues simultaneously in samples using modified QuEChERS methods. The results showed that no pesticides were detected in 248 samples. Pesticides of different levels were detected in 152 samples, of which 69 samples exhibited residue concentrations exceeding maximum residue limit of European Union. The acute and chronic dietary exposure risk of 15 pesticides in eight minor vegetables were accepted. The risk ranking result showed the most samples contained low-risk pesticides. The results will provide a reference for designing future pesticide supervision programs and risk management programs.

Risk Assessment of Pesticide Residues in Chinese Litchis

ABSTRACT

The presence of pesticide residues in fruit has been of extensive concern worldwide. Pesticide residues in 150 litchi samples collected in the People's Republic of China were measured, and the dietary exposure risks to consumers were evaluated. The litchi samples were screened by gas chromatography and ultraperformance liquid chromatography with tandem mass spectrometry for the possible presence of 57 pesticides. Seventeen pesticides were detected, and 70.7% of samples contained residues of one or more pesticides. The most frequently detected pesticide (36% of samples) was diflubenzuron. Carbofuran in one sample exceeded its maximum residue limit by 125%. In dietary exposure assessments, all concentrations below the limit of detection (LOD) were calculated as 0, 0.5 × the LOD, or at the LOD separately, and these assessments indicated that the chronic health risks from these dietary exposures were extremely low. For acute exposures, carbofuran was at 11.08% of the acute reference dose, and all other pesticides were <2% of the acute reference dose. The findings indicated that the presence of pesticide residues in litchis should not be considered a public health problem.

HIGHLIGHTS

Dietary Risk Assessment and Ranking of Multipesticides in Dendrobium officinale

The presence of pesticide residues in Dendrobium officinale (D. officinale), a commonly used herbal medicine, has attracted much attention in recent years. Therefore, this study presents the levels of 141 pesticide residues in forty D. officinale samples, which were measured by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). And we used a deterministic estimate model to assess chronic and acute dietary exposure risk, as well as the cumulative risks for adults, children, and specific groups of consumers. Furthermore, the residual risk of individual pesticides was sorted by adapting the matrix-ranking scheme. In 92.5% of the samples, 43 pesticides were detected, of which difenoconazole had the highest detection frequency. Multiple residues were detected in 85.0% of the samples, and one sample contained even up to 17 pesticides. The chronic hazard quotient (HQc) and the acute hazard quotient (HQa) were far below 100%, and both cumulative chronic and acute hazard indices (HI) did not exceed 100%. The risk scoring scheme showed that four pesticides were considered to pose a comparatively potential high risk, including difenoconazole, carbofuran, fipronil, and emamectin benzoate. The results indicated that the occurrence of pesticide residues in D. officinale could not pose a serious health problem to the public.

Worldwide survey of pesticide residues in citrus-flavored soft drinks

After more than ten years since pesticide residues were detected in citrus-flavored soft drinks, this study reveals that the situation has not changed. A new sensitive multiresidue UHPLC-MS/MS method has been validated for 88 pesticides, which was used to analyze 200 samples manufactured in 67 countries, 80% corresponding to fruit-based soft drinks. The results show that 98% of the samples collected worldwide contained at least one pesticide, and 85% of them contained more than 4 pesticides. 40 out of 88 target compounds were quantified among the screened samples. Europe was the world region with the highest total amount of pesticides, probably due to the higher content of juice concentrate in samples, which may be the main source of the pesticide residues. Nevertheless, residues were also found in samples with no juice, so water quality also plays an important role as the main ingredient of citrus-flavored soft drinks.

Promoting Food Safety in Local Value Chains: The Case of Vegetables in Vietnam

Background: Food quality and safety concerns in low- and middle-income countries are often addressed using stringent standards and formal contracts between farmers and buyers. Many studies have investigated the welfare implications of these control mechanisms for small-scale farmers in modern value chains, including exports and supermarkets. Conversely, few studies have focused on the potential of certification and contracts to tackle food safety issues within local traditional value chains. Methods: This study uses a discrete choice experiment to explore the preferences of vegetable farmers (n = 301) in northern Vietnam for different types of certification schemes–including third-party certification and participatory guarantee systems–and contracts. Results: Farmers are willing to accept a 49% lower price per kilogram for their vegetables to enter into a contract with a buyer, provided that pesticide use restrictions are feasible and the buyer is fully committed and trustworthy. However, they are strongly averse to organic farming, as they would require a 40% premium per kilogram to produce organically. They would also request a 21% premium to accept selling to an unknown buyer. Farmers highly value contracts that entail large purchase quantities, long duration and pesticide provision. Although the estimated willingness-to-accept values may seem very large, they make sense in the context of highly perishable produce. Conclusion: Our findings urge both policy makers and researchers to not only focus on modern value chains but also on local traditional value chains to tackle food safety issues in low- and middle-income countries, as we show that farmers are willing to produce safe vegetables for the local market when trading with buyers under beneficial conditions.

Human health risk assessment of pesticide residues in honeysuckle samples from different planting bases in China

The buds and initial flowers of honeysuckle (Lonicera japonica Thunb.) are most widely used in traditional Chinese medicines (TCMs). In recent years, the problem of pesticide residues in honeysuckle has attracted much attention. This research aimed to study pesticide residual situation of honeysuckle in China and estimate the potential health risks for consumers using the HQ (hazard quotient) and HI (hazard index) methods. A reliable and robust method was established to determine and quantify 137 pesticide residues simultaneously by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) for 151 honeysuckle samples from different planting bases in China in 2017 and 2018. Fifty-four pesticides were detected in total, including 10 unauthorized pesticides (chlorpyrifos, fipronil, carbofuran, omethoate, isofenphos-methyl, triazophos, methomyl, dimethoate, methidathion, and methamidophos). One hundred and fifty (99.3%) samples contained at least 1 and up to 31 pesticides and/or their metabolites, with concentrations ranging from 0.001 to 3.087 mg/kg. Carbendazim, chlorbenzuron, imidacloprid, chlorpyrifos, and acetamiprid were the most frequently detected pesticides in 2017 and 2018, and the corresponding detection rates were 95.31%, 64.06%, 65.63%, 53.13%, 57.81%, and 98.85%, 88.51%, 70.11%, 77.01%, 57.47%, respectively. The acute hazard quotient (HQ_a) of carbofuran was 1.54 for specific population (fetus, infants, and pregnant or nursing women), which indicated that it posed a potential acute health risk. In the cumulative risk assessment, the acute hazard index (HI_a) of insecticides in honesuckle for children and the specific population were 1.34 and 3.36, respectively, suggesting that they posed potential acute cumulative health risks. These results were of theoretical and practical value for evaluating the safety of honeysuckle and improving its quality and safety.

Waveguide-Based Fluorescent Immunosensor for the Simultaneous Detection of Carbofuran and 3-Hydroxy-Carbofuran

Carbofuran (CBF) is an efficient and broad-spectrum insecticide. As testing indicators for water quality and agricultural products, CBF and its metabolite 3-hydroxy-carbofuran (3-OH-CBF) are regulated by many countries. The detection of CBF and 3-OH-CBF is of great importance for the environment and human health. However, an immunosensor detection method for the simultaneous analysis of CBF and 3-OH-CBF remains unavailable. Herein, we report a waveguide-based fluorescent immunosensor for detecting CBF and 3-OH-CBF, synchronously. The immunosensor is based on a broad-spectrum monoclonal antibody with high binding affinity against CBF and 3-OH-CBF. The linear detection ranges for CBF and 3-OH-CBF are 0.29-2.69 and 0.12-4.59 μg/L, with limits of detection of 0.13 μg/L for CBF and 0.06 μg/L for 3-OH-CBF, respectively. The whole detection process for each cycle is approximately 30 min. The results show a good application prospect for the rapid detection of CBF and 3-OH-CBF in water or agricultural products.

Resolving the twin human and environmental health hazards of a plant-based diet

Food can be health-giving. A global transition towards plant-based diets may equally help curb carbon emissions, slow land-system change and conserve finite resources. Yet, projected benefits of such 'planetary health' diets imperfectly capture the environmental or societal health outcomes tied to food production. Here, we examine pesticide-related hazards of fruit and vegetable consumption, and list proven management alternatives per commodity, geography and chemical compound. Across countries, pesticide use in these alleged healthful foods is extensive with up to 97% food items containing residues and up to 42% posing dietary risks to consumers. Multiple residues are present in 70-92% of US- and China-grown stone fruit while 58% US cauliflower is tainted with neonicotinoid insecticides. Science-based alternatives and decision-support frameworks can help food producers reduce risks and potential harm by deliberately abstaining from pesticide use. As such, opportunities abound to advance 'win-win' diets that simultaneously nurture human health and conserve global biodiversity.

Comprehensive assessment for the residual characteristics and degradation kinetics of pesticides in Panax notoginseng and planting soil

Incorrect and excess usage of pesticides during crop cultivation poses a serious threat to human health and ecosystems. In this study, we tested for the presence of 201 pesticide residues in 90 batches of Panax notoginseng (P. notoginseng) and 10 batches of planting soil. Pesticide residue characteristics and the relationship between pesticides present in P. notoginseng and the soil were discussed. Twenty-nine pesticides were detected in P. notoginseng samples and 15 pesticides were found in the soil samples. In P. notoginseng samples, the 68.9% of the identified pesticides were fungicides, and six fungicides (procymidone, iprodione, pyrimethanil, propiconazole, dimethomorph and tebuconazole) were found in >90% of the samples. Nine insecticides were found, with one insecticide, chlorpyrifos, detected in 93.3% of the P. notoginseng samples. The residual concentrations of 17 pesticides were found at levels exceeded the "non-Chinese" maximum residue levels (MRLs) for Ginseng and 17 pesticides were found at levels exceeding the MRLs set by China for "pollution-free" P. notoginseng. We observed no significant differences in pesticide residues were found on P. notoginseng from different cultivation areas. We also analyzed the degradation kinetics of pesticides in the soil, as well as their bioconcentration factors (BCFs), and found that the fungicides iprodione and myclobutanil displayed strong uptake from the soil to the root of P. notoginseng. Together, our data suggest that fungicides should be considered as key monitoring substances in P. notoginseng and planting soil.

Supercritical Fluid Extraction of Pesticides and Insecticides from Food Samples and Plant Materials

The principal intention of this study is presenting the attempts carried out for extracting, separating, and determining of the pesticide and insecticide residues existing in food and plant samples. In this regard, a set of content, including the explanations about the supercritical fluid extraction (SFE), supercritical fluid chromatography, and various types of pesticides are indicated. Besides, the parameters affecting the pesticides extraction composed of temperature, pressure, modifier, drying agent, and so on are discussed. Also, examples of insecticides extraction by SFE technique as an important subset of pesticides are indicated. Along with these items, some interesting works, concerning the innovations implemented in the field of SFE of pesticide and insecticide residues from foodstuff and plants are depicted.

In vitro exposure to thiacloprid-based insecticide formulation promotes oxidative stress, apoptosis and genetic instability in bovine lymphocytes

A proprietary thiacloprid-based neonicotinoid insecticide formulation is widely used in agriculture to protect vegetables and fruit against various pests. However, its effect on animal cells has not been fully elucidated. In this study, bovine peripheral lymphocytes were incubated with different concentrations of this formulation (10; 30; 60; 120 and 240 μg.mL^-1) for 4 h to address the potential cytotoxic and genotoxic effects of the insecticide. Insecticide formulation treatment resulted in decreased cell viability and proliferation, p53-mediated cell cycle arrest at the G₀/G₁ phase, and apoptosis induction accompanied by elevated levels of mitochondrial superoxide and protein carbonylation. Oxidant-based DNA damage and DNA damage response (DDR) were also observed, namely the formation of micronuclei, DNA double-strand breaks and slightly elevated recruitment of p53 binding protein (53BP1) foci. Our results contribute to the elucidation of insecticide effects on animal lymphocyte cultures after short-term exposure. Due to increased application of neonicotinoids worldwide, resulting in both higher yields and adverse effects on non-target animals and humans, further in vivo and in vitro experiments should be performed to confirm their cytotoxic and genotoxic activities during short-term exposure.

Residue levels and health risk of pesticide residues in bell pepper in Shandong

The purpose of this study was to investigate pesticide residues in bell peppers from Shandong Province, China. A total of 299 samples were collected from 17 cities in 2016. The concentrations of 26 pesticide residues were determined by gas chromatography with mass spectrometry (GC-MS). The results showed that there were 25 pesticides (15 OPs, 7 PYs, 3 CBs) found in 86 bell pepper samples, and the total number of positives was 120. The total frequency was 28.76%. The detection frequency for OPs, PYs and CBs was 16.39%, 12.37% and 3.01%, respectively. The most frequently detected pesticide was bifenthrin, with the frequency of 5.02%. 5.35% of samples contained pesticide residues above the maximum residue limits (MRLs) set by China. 7.36% of samples contained more than one pesticide. The values of %ADI were below 100, while the %ARfD of carbofuran and methidathion exceeded 100 for children. The cumulative risk was highest for OPs. From the public health point of view, the levels of pesticide residues in bell peppers do not pose a serious health risk to adults, but the acute health risk to children should be paid more attention.

Novel three-Dimensional molecularly imprinted polymer-coated carbon nanotubes (3D-CNTs@MIP) for selective detection of profenofos in food

A new and facile method for selective measurement of profenofos (PFF) using a simple flow-injection system with a molecularly-imprinted-polymer-coated carbon nanotube (3D-CNTs@MIP) amperometric sensor is proposed. The 3D-CNTs@MIP was synthesized by successively coating the surface of carboxylated CNTs with SiO₂ and vinyl end groups, then terminating with molecularly imprinted polymer (MIP) shells. MIP was grafted to the CNT cores using methacrylic acid (MAA) monomer, ethylene glycol dimethacrylate (EGDMA) as cross linker, and 2,2'-azobisisobutyronitrile (AIBN) as initiator. We constructed the PFF sensor by coating the surface of a glassy carbon electrode (GCE) with 3D-CNTs@MIP and removed the imprinting template by solvent extraction. Morphological and structural characterization reveal that blending of the MIP on the CNT surface significantly increases the selective surface area, leading to greater numbers of imprinting sites for improved sensitivity and electron transfer. The 3D-CNTs@MIP sensor exhibits a fast response with good recognition when applied to PFF detection by cyclic voltammetry and amperometry. The PFF oxidation current signal appears at +0.7 V vs Ag/AgCl using 0.1 M phosphate buffer (pH 7.0) as the carrier solution. The designed 3D-imprinted sensor provides a linear response over the range 0.01-200 μM (r² = 0.995) with a low detection limit of 0.002 μM (3σ). The sensor was successfully applied to detection of PFF in vegetable samples.

Environmental characterization of 4,4'-dichlorobenzophenone in surface waters from Macao and Hong Kong coastal areas (Pearl River Delta) and its toxicity on two biological models: Artemia salina and Daphnia magna

The Pearl River Delta (PRD) is one of the areas with higher environmental concentration of organochlorine pesticides (OCPs), being DDT one of the most abundant. In this work, 4,4'-dichlorobenzophenone (4,4'-DCBP), a common metabolite of dicofol (DDT related) and DDT, was quantified in surface waters of Hong Kong and Macao, together with the analysis of physicochemical and nutrients parameters. Hong Kong presented higher 4,4'-DCBP mean levels (12.50 ng/L) than Macao (4.05 ng/L), which may be due to the use of dicofol as a pesticide and DDT as antifouling-paint for ships. The region presented a possible eutrophication state due to the high nutrients' concentration. For the first time, toxicity evaluation of this metabolite in Artemia salina and Daphnia magna was done, in order to compute valid EC₅₀s and theoretically evaluate the risk in the PRD. The toxicity results (EC₅₀ = 0.27 mg/L for A. salina; and EC₅₀ = 0.17 mg/L and LC₅₀ = 0.26 mg/L for D. magna), together with the 4,4'-DCBP levels quantified, indicated a low environmental risk.

Risk Of Human Dietary Exposure To Organochlorine Pesticide Residues In Fruits From Ghana

The objectives of this present study were to assess the level of organochlorine pesticide (OCP) residues in fruits and to determine the potential health risks associated with the exposure to these pesticides. A total of 120 fruits (watermelon, pineapple, and banana) were collected from five communities and a local market within the Mampong Municipality and analyzed for organochlorine pesticide residues. The results showed that the concentrations ranged from not detectable (ND)-48.22 ng/g for DDTs, ND-19.03 ng/g for HCHs, ND-4.10 ng/g for CHLs, ND-22.84 ng/g for Aldrin, and ND-11.53 ng/g for other OCPs. Levels of methoxychlor, Aldrin and gamma-hexachlorocyclohexane (HCH) exceeded the maximum residue limits in watermelon. Estimated health risk revealed that Aldrin in watermelon could pose potential toxicity to the consumer. Estimated average daily intake for Aldrin was above the acceptable average daily intake.

Estimating acute and chronic exposure of children and adults to chlorpyrifos in fruit and vegetables based on the new, lower toxicology data

This paper presents, for the first time, results for chlorpyrifos (CHLP) in Polish fruits and vegetables over the course of a long period of research, 2007-2016, with toxicological aspects. The challenge of this study was to re-evaluate the impact of chlorpyrifos residues in fruit and vegetables on health risk assessed via acute and chronic exposure based on old and new, lower, established values of: Average Daily Intakes (ADIs)/Acute Reference Doses (ARfDs) and Maximum Residue Levels (MRLs). A total of 3 530 samples were collected, and CHLP in the range of 0.005-1.514 mg/kg was present in 10.2% of all samples. The MRL was exceeded in 0.7% of all samples (MRL established in 2009-2015), and recalculation yielded a much greater number of violations for the new MRL (2016), which exceeded 2.9% of all samples. Acute exposure to CHLP calculated according to the old, higher toxicological data (0.10 mg/kg bw/day), does not exceed 14% of its respective ARfDs for adults and both groups of children, but when calculated for incidental cases according to the current value (ARfD 0.005 mg/kg bw) for infants and toddlers, was above 100% of its respective ARfDs in: white cabbage (263.65% and 108.24%), broccoli (216.80% and 194.72%) and apples (153.20% and 167.70%). The chronic exposure calculated for both newly established ADI values (0.001 mg/kg bw/day and 0.100 mg/kg bw/day) appears to be relatively low for adults and children.

Simultaneous analysis of multiple pesticide residues in minor fruits by ultrahigh-performance liquid chromatography/hybrid quadrupole time-of-fight mass spectrometry

An ultrahigh-performance liquid chromatography/hybrid quadrupole time-of-fight mass spectrometry (UPLC/QTOF-MS) method for the simultaneous identification and quantification of 50 multi-class pesticides in minor fruits is reported. The method consists of a sample extraction step, followed by analysis of the pesticides by UPLC/QTOF-MS. Satisfactory chromatographic separation was achieved over a 20min runtime. The pesticides were identified by the accurate mass measurements of the protonated molecules ([M+H]⁺) and their main fragment ions, isotopic pattern analysis and retention time matching. The mass accuracy obtained was below 2ppm error for all the pesticides analysed. The method was validated by spiking starfruit with the 50 analytes. Satisfactory results regarding sensitivity and linearity were obtained. The method was successfully applied to the analysis of 87 real-world starfruit and Indian jujube samples, demonstrating its applicability for the routine analysis of multiple pesticide residues in minor tropical fruits.

Too much to handle? Pesticide dependence of smallholder vegetable farmers in Southeast Asia

This study aimed to understand farmers' knowledge, attitudes, and practices regarding agricultural pest management and synthetic pesticide use in Southeast Asia. Data were used from 900 farm households producing leaf mustard (Brassica juncea (L.) Czern. et Coss.) and yard-long bean (Vigna unguiculata subsp. sesquipedalis (L.) Verdc.) in Cambodia, Laos and Vietnam. Farmers heavily depended on synthetic pesticides as their main method of pest control. Most farmers were aware of the adverse health effects associated with pesticide use and covered body parts while spraying, but also considered pesticides to be highly effective and indispensable farm inputs. Farmers were largely unable to distinguish between common beneficial and harmful arthropods. Greater knowledge about this was associated with less pesticide use while greater awareness of pesticide health risks was associated with fewer observed poisoning symptoms. For the average farm and while controlling for other factors, farmers who sought advice from friends and neighbors used 45% less pesticide, but those who sought advice from pesticide shopkeepers used 251% more pesticide. Pesticide use was 42% less when a woman was in charge of pest management and 31% less when farmers had adopted biopesticides. These findings suggest relevant entry points for interventions aimed at reducing pesticide dependence.

Pesticide residues in nut-planted soils of China and their relationship between nut/soil

Twenty-nine pesticide residues in nut-planted soils from China were investigated. One organophosphate (chlorpyrifos) was detected in 5.3% soils, and the residue levels of 7.2 μg/kg to 77.2 μg/kg. The concentrations of six organochlorines (DDT, HCH, endosulfan, quintozene, aldrin and dieldrin) detected in 78.9% soils were 0.6 μg/kg to 90.1 μg/kg. The residue levels of six pyrethroids (bifenthrin, fenpropathrin, cyhalothrin, cypermethrin, fenvalerate and deltamethrin) detected in 65.8% soils were 1.5 μg/kg to 884.3 μg/kg. Triadimefon and buprofezin were found in 71.1% and 52.6% samples, respectively, with the corresponding concentrations of 9.8 μg/kg to 193.7 μg/kg and 87.9 μg/kg to 807.4 μg/kg. The multiple residues were found in 76.3% soils. A significant correlation between pesticide residues in nuts and soils was observed, with the correlation coefficient (r) 0.83 (P < 0.001). In addition, the bioconcentration factor (BCF) values for the explanation of pesticides from soils into nuts were ranged from 0.8 to 16.5. The results showed that some pesticides could accumulate in nut by the uptake effect from soil.

Pesticide analysis using nanoceria-coated paper-based devices as a detection platform

We report the first use of a paper-based device coated with nanoceria as a simple, low-cost and rapid detection platform for the analysis of organophosphate (OP) pesticides using an enzyme inhibition assay with acetylcholinesterase (AChE) and choline oxidase (ChOX). In the presence of acetylcholine, AChE and ChOX catalyze the formation of H2O2, which is detected colorimetrically by a nanoceria-coated device resulting in the formation of a yellow color. After incubation with OP pesticides, the AChE activity was inhibited, producing less H2O2, and a reduction in the yellow intensity. The assay is able to analyze OP pesticides without the use of sophisticated instruments and gives detection limits of 18 ng mL(-1) and 5.3 ng mL(-1) for methyl-paraoxon and chlorpyrifos-oxon, respectively. The developed method was successfully applied to detect methyl-paraoxon in spiked vegetables (cabbage) and a dried seafood product (dried green mussel), obtaining ∼95% recovery values for both sample types. The spiked samples were also analyzed using LC-MS/MS as a comparison to the developed method and similar values were obtained, indicating that the developed method gives accurate results and is suitable for OP analysis in real samples.

Residue levels and risk assessment of pesticides in nuts of China

The pesticide residue levels of three nuts (chestnut, walnut, pinenut) collected from seven main producing areas of China were investigated. Twenty-nine pesticides, including organophosphates (OPs), organochlorines (OCs), pyrethroids (PYs) and two fungicides (triadimefon and buprofezin) were analyzed by gas chromatography (GC). Four OPs (acephate, dimethoate, chlorpyrifos and parathion-methyl) were found in 11.4% samples, with the concentrations of 19.0 µg kg(-1) to 74.0 µg kg(-1). Six OCs (DDT, HCH, endosulfan, quintozene, aldrin and dieldrin) were found in 18.2% samples, with the concentrations of 2.0 µg kg(-1) to 65.7 µg kg(-1). Among OCs, p,p-DDE and α-HCH were the dominant isomer for DDT and HCH. Five PYs (fenpropathrin, fenvalerate, cypermethrin, bifenthrin and cyhalothrin) were found in 15.9% samples, with the concentrations of 2.5 µg kg(-1) to 433.0 µg kg(-1). Fenpropathrin was the most frequently detected pesticide. In addition, triadimefon and buprofezin were detected only in two samples. For the tested nuts, 25.0% samples with multiple residues (containing more than two pesticides) were noted, even up to 9.1% samples with five pesticide residues. The residue of 15.9% samples was higher than the maximum residue limits (MRLs) of China. The short-term risks for the tested nuts were below 1.2%, and the highest long-term risk was 12.58%. The cumulative risk (cHI) for the tested pesticides were 8.43% (OPs), 0.42% (OCs), 12.82% (PYs) and 0.15% (fungicides), respectively. The total cHI was 21.82%. There was no significant health risk for consumers via nuts consumption.

Pesticides in persimmons, jujubes and soil from China: Residue levels, risk assessment and relationship between fruits and soils

Extreme and uncontrolled usage of pesticides produces a number of problems for vegetation and human health. In this study, the existence of organophosphates (OPs), organochlorines (OCs), pyrethroids (PYs) and fungicides (FUs) were investigated in persimmons/jujubes and their planted soils, which were collected from China. One OP (dimethoate), three OCs (DDT, quintozene and aldrin), six PYs (bifenthrin, fenpropathrin, cyhalothrin, cypermethrin, fenvalerate and deltamethrin) and two FUs (triadimefon and buprofezin) were found in 36.4% of persimmons and 70.8% of jujubes, with concentrations from 1.0 μg/kg to 2945.0 μg/kg. The most frequently detected pesticides in the two fruits were fenpropathrin in persimmons and cypermethrin in jujubes, with the detection frequencies of 30.0% and 22.7%, respectively. The residues of 4.5% (persimmon) and 25.0% (jujube) of samples were higher than the maximum residue limits (MRLs) of China. Compared with the fruits, more types of pesticides and higher residues were observed in their planted soils. The most frequently detected pesticides were HCH in persimmon soil and DDT in jujube soil, with the detection frequencies of 10.9% and 12.7%, respectively. For the tested samples, 39.1% of fruit samples and 63.0% of soil samples with multiple residues (containing more than two pesticides) were noted, even up to 8 residues in fruits and 14 residues in soils. Except for cyhalothrin, the other short-term risks for the tested pesticides in the fruits were below 10%, and the highest long-term risk was 14.13% for aldrin and dieldrin. There was no significant health risk for consumers via consumption of the two fruits.

Multiresidue pesticide analysis in nutraceuticals from green tea extracts by comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry

A new analytical method was developed and validated for simultaneous analysis of 423 pesticides, isomers, and pesticide metabolites in nutraceutical products obtained from green tea (Camellia sinensis) extract. Response surface methodology was employed to optimize a generic extraction method. The automated extraction procedure was achieved in a simple disposable pipet extraction. Comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry was used for the separation and detection of all the analytes. The method was validated by taking into consideration the guidelines specified in European SANCO/12571/2013 Guideline 2013 and Commission Decision 2002/657/EC. The extraction recoveries were in a range of 81.6-113.0%, with coefficient of variation <6.4%. The limits of decision for the analytes are in the range 0.04-4.15μgkg(-1). The detection capabilities for the analytes are in the range 0.07-6.92μgkg(-1). The 423 compounds behave dynamic in the range 0.1-200μgkg(-1) concentration, with correlation coefficient >0.99. This validated method has been successfully applied on screening of pesticide residues in one hundred and twenty-four different commercial nutraceutical products from green tea extract, and methamidophos, resmethrin, propoxur, tridemorph, ethiofencarb, flamprop isopropyl, furalaxyl, bifenthrin and fenpropathrin were detected in a few samples tested in this study.

A rapid immunomagnetic-bead-based immunoassay for triazophos analysis

Schematic illustration of a direct competitive immunomagnetic-bead-based enzyme-linked immunosorbent assay (IMB-ELISA) to detect the triazophos pesticides.