Pesticide Residues and Health Risk Assessment in Tomatoes and Lettuces from Farms of Metropolitan Region Chile

Exploring the dynamic behaviors of five pesticides in lettuce: Implications for consumer health through field and modeling experiments

Lettuce, a globally consumed nutritious vegetable, is often linked to concerns regarding pesticide residues. To address this issue, we conducted field trials and utilized dynamiCROP modeling to examine the uptake, distribution, translocation, and dissipation of five pesticides (λ-cyhalothrin, difenoconazole, acetamiprid, dimethomorph, and β-cypermethrin) commonly detected in lettuce. At harvest, pesticides residues were below the maximum residue limits (MRLs) at 0.05, 0.39, 0.047, 0.72, and 0.072 mg kg-1, respectively. Simulation results elucidated distinct behaviors of the pesticides following application to lettuce foliage across various compartments. However, all pesticides exhibited a common dissipation trend, initially stabilizing or increasing before gradually declining. For all five pesticides, the largest contribution of residues on lettuce leaves came from the leaf surface during the early period after application, and from the soil in the long term. Health risk assessments indicated negligible risks associated with consuming lettuce containing these pesticides, both in the short and long term.

Organophosphorus pesticide contaminants in fruits and vegetables: A meta-analysis

The worldwide demand for organophosphorus pesticides (OPs) in food production has raised concerns about pesticide residues. Meta-analysis, proven effective in assessing contaminants like aflatoxins and organotin compounds, is applied here to comprehensively study OP contamination in fresh fruits and vegetables. Employing Comprehensive Meta-Analysis V3.0 software, we meticulously examined 24 relevant articles encompassing 69,467 data points. Our findings revealed that while the residual concentrations of OPs (such as chlorpyrifos and profenofos) in most fruits and vegetables have typically met international or national safety standards, including Codex Alimentarius Commission, European Union, British, and Chinese standards, there are some instances in which the maximum residue limits have been exceeded, posing safety risks. Therefore, significant efforts are required to maintain residual OP contamination at safe concentrations.

The concentration of pesticides in tomato: a global systematic review, meta-analysis, and health risk assessment

To improve farming productivity, a large number of pesticides have been used worldwide in recent decades, leading to the pollution of soil, agri-products, and water, directly/indirectly affecting human health. In this regard, many studies were conducted in different countries on residual pesticides in the environment. In the current study, residual pesticides including chlorpyrifos, cypermethrin, diazinon, malathion, and metalaxyl in tomatoes were meta-analyzed and health risk of consumers was estimated. For this purpose, based on a systematic review, data from 47 studies were extracted and meta-analyzed, and the health impact of pooled concentrations was assessed via a health risk method. According to the results, metalaxyl had the most concentration followed by malathion, cypermethrin, diazinon, and chlorpyrifos, respectively. The non-carcinogenic risk (n-CR) was calculated from crop consumption also showed that exposure to malathion has the most risk. Among the investigated communities, Iranian consumers were in considerable health risk (THQ > 1). Considering that the potential for the use of pesticides will increase with the need for food in the future, hence, governments must manage the usage by governments via alternative methods such as cultural, biological, physical, and genetic modifications.

Cumulative health risk assessment of pesticide residues in apple products in the Northwest of Iran using Monte Carlo simulation

Pesticide residues in fruits and vegetables cause serious health issues, especially among children. This research was carried out to monitor and evaluate the risks of organophosphate pesticide residues in Maragheh County apple products from 2020. The Monte Carlo Simulation approach (MCS) was used to evaluate the non-cancerous effects of exposure to pesticide residues in adults and children. Apple samples were taken every two weeks at the Maragheh central market during the summer and fall months. In this study, seventeen pesticide residues in 30 apple samples were estimated using a modified QuECheRS extraction technique coupled with GC/MS. Of the seventeen organophosphate pesticides, thirteen were identified as pesticide residues (76.47%). The highest concentration found in the apple samples was associated with chlorpyrifos pesticide at 1.05 mg/kg. Pesticide residues exceeding the maximum residue limits (MRLs) were found in 100% of apple specimens, and more than 75% of the samples contained ten or more pesticide residues. Approximately 45%-80% of pesticide residues on apple samples were removed after washing and peeling. Chlorpyrifos pesticide had the highest health quotient (HQ) for men, women, and children with values of 0.046, 0.054, and 0.23, respectively. Cumulative risk assessment (CRA) of non-carcinogenic effects indicates that there is no significant health risk in the adult age group from apple consumption (HI < 1). Nevertheless, children are at high non-cancer risk from eating unwashed apples (HI = 1.3). This finding shows that high levels of pesticide residues in apple samples, especially unwashed apples, can be a serious concern for the health of children. To better protect consumer health, continuous and regular monitoring, strict regulations, training, and awareness of farmers, especially control pre-harvest interval (PHI) is recommended.

Experimental Design and Multiple Response Optimization for the Extraction and Quantitation of Thirty-Four Priority Organic Micropollutants in Tomatoes through the QuEChERS Approach

The chemical contamination in fruit and vegetables represents a challenging analytical issue, with tomatoes deserving to be investigated as they are fundamental components of the Mediterranean diet. Polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs) and nitro-PAHs contamination is of serious concern, due to particulate deposition and to uptake from contaminated soils and water. However, time-consuming, non-simultaneous and/or non-eco-friendly extraction procedures are typically used to investigate organic contamination in tomatoes, with nitro-PAHs that have not yet been studied. Based on these premises, this work reports the development of a QuEChERS-based approach, coupled with gas chromatography/mass spectrometry, for the simultaneous determination of 16 PAHs, 14 PCBs and 4 nitro-PAHs in three tomato cultivars. The effect of dichloromethane, cyclohexane and acetone, as well as of four clean-up phases were studied through the advanced combination of full factorial experimental design and multiple response optimization approaches. The final protocol, based on cyclohexane extraction followed by a double purification step with primary secondary amine and octadecyl silica and a sulfuric acid oxidation, led to 60–120% recoveries (RSD% < 15%). Good repeatability (inter-day precision <15%) and negligible matrix effect (<16%) were confirmed and the protocol was applied to the analysis of real tomato samples purchased in a local market.

Efficacy of some washing solutions for removal of pesticide residues in lettuce

Background

When previous studies were examined, it was reported that a wide variety of pesticide residues were detected in lettuce (Bakırcı et al. in Food Chem 160:379–392, 2014; Balkan and Yılmaz in Food Chem 384:132516, 2022; Qin et al. in Food Res Int 72:161–167, 2015; Selim et al. in Res J Environ Sci 5:248–258, 2011). In addition, pesticide-contaminated lettuce poses a risk to consumers as it is a fresh food that is eaten raw. Therefore, pesticide removal processes must be applied before consumption. Some pesticide removal process, such as storage and heat treatment cannot be applied to lettuce because of unshelled, no long shelf life and consuming as fresh. Different practical methods are needed for the removal of pesticides process. The recommendations of suitable methods for cleaning salad materials in ready-to-eat sector, hotels, restaurants and homes are very important. It is important to reduce pesticide residues in vegetables and fruits that are consumed raw by washing them with non-toxic solutions. These approaches aim to protect public health. The study conducted in 2021 determined the effect of various washing treatments. For this purpose, before the washing trials, QuEChERS method was validated for determination of 7 pesticides in lettuce, by liquid chromatography–tandem mass spectrometry (LC–MS/MS). Lettuce plants were grown in the greenhouse for the study. Lettuces were brought to the laboratory 24 h after pesticides were applied in the greenhouse. The samples were kept in 2 L washing solution for pesticide analysis.

Results

The processing factor values of all washing applications were found below 1. This result shows that the residue level was reduced by washing solutions. Among the washing solution treatments, the rice vinegar washing solution was found to be most effective in reducing the pesticide residues which was due to the high degree in the pesticide degradation. Washing with filtered rice water also exhibited equivalent reduction capability similar to rice vinegar.

Conclusions

The effectiveness of washing solutions was different for boscalid, deltamethrin, fluopcolide, fluopyram, pyrimethanil, pyraclostrobin and sulfoxaflor. However, when the average removal of these pesticides was evaluated, the most effective solutions were rice vinegar, filtered rice water, carbonated water, NaCl + grape vinegar, hot tap water (40 °C), grape vinegar (6% acetic acid), grape vinegar + water, cold tap water (20 °C), lemon juice, baking soda water, grape vinegar (8% acetic acid), filtered mint water and grape vinegar (4% acetic acid), respectively. It was concluded that some of the solutions used in this study can significantly reduce exposure to pesticides for consumers.

Toxic effects of fludioxonil on the growth, photosynthetic activity, oxidative stress, cell morphology, apoptosis, and metabolism of Chlorella vulgaris

Fludioxonil is widely used in the control of crop diseases because of its broad spectrum and high activity, but its presence is now common in waterways proximate to treated areas. This study examined the toxic effects and mechanisms of fludioxonil on the microalgal taxa Chlorella vulgaris. The results showed that fludioxonil limited the growth of C. vulgaris and the median inhibitory concentration at 96 h was 1.87 mg/L. Concentrations of 0.75 and 3 mg/L fludioxonil reduced the content of photosynthetic pigments in algal cells to different degrees. Fludioxonil induced oxidative damage by altering C. vulgaris antioxidant enzyme activities and increasing reactive oxygen species levels. Fludioxonil at 0.75 mg/L significantly increased the activity of antioxidant enzymes. The highest level of activity was 1.60 times that of the control group. Both fludioxonil treatment groups significantly increased ROS levels, with the highest increase being 1.90 times that of the control group. Transmission electron microscope showed that treatment with 3 mg/L fludioxonil for 96 h disrupted cell integrity and changed cell morphology, and flow cytometer analysis showed that fludioxonil induced apoptosis. Changes in endogenous substances indicated that fludioxonil negatively affects C. vulgaris via altered energy metabolism, biosynthesis of amino acids, and unsaturated fatty acids. This study elucidates the effects of fludioxonil on microalgae and the biological mechanisms of its toxicity, providing insights into the importance of the proper management of this fungicide.

A Cheminformatics Study Regarding the Human Health Risks Assessment of the Stereoisomers of Difenoconazole

Difenoconazole is a chemical entity containing two chiral centers and having four stereoisomers: (2R,4R)-, (2R,4S)-, (2S,4R)- and (2S,4S)-difenoconazole, the marketed product containing a mixture of these isomers. Residues of difenoconazole have been identified in many agricultural products and drinking water. A computational approach has been used to evaluate the toxicological effects of the difenoconazole stereoisomers on humans. It integrates predictions of absorption, distribution, metabolism, excretion and toxicity (ADMET) profiles, prediction of metabolism sites, and assessment of the interactions of the difenoconazole stereoisomers with human cytochromes, nuclear receptors and plasma proteins by molecular docking. Several toxicological effects have been identified for all the difenoconazole stereoisomers: high plasma protein binding, inhibition of cytochromes, possible hepatotoxicity, neurotoxicity, mutagenicity, skin sensitization potential, moderate potential to produce endocrine disrupting effects. There were small differences in the predicted probabilities of producing various biological effects between the distinct stereoisomers of difenoconazole. Furthermore, there were significant differences between the interacting energies of the difenoconazole stereoisomers with plasma proteins and human cytochromes, the spectra of the hydrogen bonds and aromatic donor-acceptor interactions being quite distinct. Some distinguishing results have been obtained for the (2S,4S)-difenoconazole: it registered the highest value for clearance, exposed reasonable probabilities to produce cardiotoxicity and carcinogenicity and negatively affected numerous nuclear receptors.

Cytoprotective and Antigenotoxic Properties of Organic vs. Conventional Tomato Puree: Evidence in Zebrafish Model

In this in vivo study, we investigated cytoprotective and antigenotoxic effects of commercial tomato puree obtained from conventional vs. organic farming systems (pesticides vs. pesticide-free agriculture, respectively). This is relevant as pesticides are widely used in agriculture to prevent pests, weeds, and the spread of plant pathogens. By exposing zebrafish to tomato puree alone and in combination with H2O2 (a well-known genotoxic agent), we analyzed the percentage of fish survival, cell viability, intracellular concentration of reactive oxygen species (ROS), DNA fragmentation index (DFI%), and genomic template stability (GTS%). Fish exposed to organic puree showed higher fish survival and cellular viability, lower DFI% and ROS, and improved GTS%. Our results suggest a higher cytoprotective and antigenotoxic effect of organic pesticide-free tomatoes, probably because the activity of natural phytochemicals is not affected by the presence of toxic residues, which are otherwise produced by pesticides used in conventional farming systems. Our study points out the importance of considering alternative strategies in agriculture to minimize the genotoxic impact of chemical pesticides.

An assessment of health risks posed by consumption of pesticide residues in fruits and vegetables among residents in the Kampala Metropolitan Area in Uganda

Background

Pesticide use for fruits and vegetable production in Uganda may result in presence of residues on produce which may pose health risks to consumers. Uganda does not have an established system for monitoring pesticide residues in fruits and vegetables and assessing potential health risks. This research aimed to conduct a health risk assessment of presence of pesticide residues in fruits and vegetables in the Kampala Metropolitan Area in Uganda.

Method

Pesticides were measured in 160 fruits and vegetables samples collected at farms, markets, street vendors, restaurants and homes; and analysed using liquid chromatography-tandem mass spectrometry and gas chromatography-mass spectrometry. Fruit and vegetable consumption information was collected from 2177 people. Pesticide concentrations were compared with European Union maximum residual limits (MRLs). Mean values of pesticide concentration residues found in the sample of fruits and vegetables; and fruits and vegetables intake and body weight were used to calculate the estimated daily intake (EDI) of pesticide residues. EDI values were compared with acceptable daily intakes (ADI) to calculate the hazard quotient by age group, and stage at which consumption happens along the chain.

Results

Overall, 57 pesticides were detected in fruits and vegetables from farm to fork. Of the 57, 39 pesticides were detected in all the fruits and vegetables studied. Concentrations of fonofos, fenitrothion and fenhexamid were above the European Union MRLs in some samples. Hazard quotients based on dietary ingestion scenarios for 18 pesticides, including dichlorvos (444) alanycarb (314), fonofos (68), fenitrothion (62), dioxacarb (55) and benfuracarb (24) and others, were above 1, indicating the possibility of chronic health risk to consumers. Chronic health risk decreased with age but was stable for stage at which consumption happens along the food chain. The number of pesticides with EDI greater than the ADI decreased with increase in age; with 18, 13, 9, 11, 8, 9, and 9 pesticides for age groups < 5, 5-12, 13-19, 20-25, 36-49 and ≥ 50 respectively.

Conclusion

Chronic dietary pesticide exposures to Ugandans are likely common, and for some pesticides result in exposure exceeding health-based benchmarks. Risks were highest for younger participants. There is an urgent need to increase monitoring and regulation of pesticides in fruits and vegetables in order to protect consumers, especially the children who are vulnerable to the adverse effects of pesticides.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40550-022-00090-9.

Revisiting pesticide pollution: The case of fluorinated pesticides

Fluorinated pesticides acquired a significant market share in the agrochemical sector due to the surge of new fluoroorganic ingredients approved in the last two decades. This growing trend has not been accompanied by a comprehensive scientific and regulatory framework entailing all their potential negative impacts for the environment, especially when considering the hazardous properties that may result from the incorporation of fluorine into organic molecules. This review aims to address the safe/hazardous dichotomy associated with fluorinated pesticides by providing an updated outlook on their relevancy in the agrochemical sector and how it leads to their role as environmental pollutants. Specifically, the environmental fate and distribution of these pesticides in the ecosystems is discussed, while also analysing their potential to act as toxic substances for non-target organisms.

Atlas of the microbial degradation of fluorinated pesticides

Fluorine-based agrochemicals have been benchmarked as the golden standard in pesticide development, prompting their widespread use in agriculture. As a result, fluorinated pesticides can now be found in the environment, entailing serious ecological implications due to their harmfulness and persistence. Microbial degradation might be an option to mitigate these impacts, though environmental microorganisms are not expected to easily cope with these fluoroaromatics due to their recalcitrance. Here, we provide an outlook on the microbial metabolism of fluorinated pesticides by analyzing the degradation pathways and biochemical processes involved, while also highlighting the central role of enzymatic defluorination in their productive metabolism. Finally, the potential contribution of these microbial processes for the dissipation of fluorinated pesticides from the environment is also discussed.

Analysis of Multi-Pesticide Residues and Dietary Risk Assessment in Fresh Tomatoes (Lycopersicum esculentum) from Local Supermarkets of the Metropolitan Region, Chile

In recent years, the official authorities in Chile have reported transgressions in the maximum residue levels of pesticides in fresh vegetables. There is no official information about traceability, pesticide levels, and potential health risks. The aim of this study was to analyse pesticide residues and their corresponding dietary risk assessments in tomatoes from supermarkets in the Metropolitan Region. Pesticides were extracted using the Quick, Easy, Cheap, Effective, Rugged and Safe, QuEChERS method, and their concentrations were determined by using chromatography with HPLC-FL/UV and GC-MS/ECD/NPD, following the Analytical Quality Control and Method Validation Procedures for Pesticides Residues Analysis in Food and Feed, SANTE guide and ISO 17025:2017 standard. In addition, a dietary risk assessment was carried out by comparing Chilean data to international references. The results reported that 9% of the samples had pesticide residue levels above the maximum residue levels permitted in Chile. All the scenarios evaluated revealed the highest estimated daily intake and hazard quotients for methamidophos and chlorpyrifos. Both the active substances used were acetylcholinesterase inhibitors and were neurotoxic under chronic risk assessment. The results showed the highest chronic hazard index in the Chilean scenario for all age groups and genders. The evidence obtained revealed that methamidophos, methomyl, and chlorpyrifos should be restricted for their use in Chilean agriculture.

Quantification of field-incurred residues of cyantraniliprole and IN-J9Z38 in cabbage/soil using QuEChERS/HPLC-PDA and dietary risk assessment

Cyantraniliprole is an anthranilic diamide insecticide used for the effective management of diamondback moth in cabbage. Dietary risk assessment of pesticides in food is a major concern now. This study developed a QuEChERS/HPLC-PDA-based highly efficient and reliable method, registering 89.80-100.11% recoveries of cyantraniliprole and its metabolite IN-J9Z38 from cabbage and soil with a relative standard deviation of 0.43-5.77%. Field experiment was conducted to study the residue dissipation of cyantraniliprole in cabbage and soil. Two foliar treatments of 10.26% formulation (Benevia) at 60 (T₁ ) and 120 (T₂ ) gram active ingredient/hectare were applied. The dissipation half-lives of cyantraniliprole in cabbage and soil were determined to be 3.5-4.2 and 3.8-5.3 days at T₁ and 3.9-4.8 and 4.1-4.7 days at T₂ , respectively. The maximum concentrations of IN-J9Z38 at T₁ and T₂ were 0.819 and 1.061 mg/kg, respectively, on the fifth day. A risk quotient value of <1 indicates no dietary risk to the consumers. The residues in the harvested cabbage were below the tolerance level of 2.0 mg/kg established by the regulatory body in India.

Non-Occupational Exposure to Pesticides: Experimental Approaches and Analytical Techniques (from 2019)

BACKGROUND

Pesticide residues are a threat to the health of the global population, not only to farmers, applicators, and other pesticide professionals. Humans are exposed through various routes such as food, skin, and inhalation. This study summarizes the different methods to assess and/or estimate human exposure to pesticide residues of the global population.

METHODS

A systematic search was carried out on Scopus and web of science databases of studies on human exposure to pesticide residues since 2019.

RESULTS

The methods to estimate human health risk can be categorized as direct (determining the exposure through specific biomarkers in human matrices) or indirect (determining the levels in the environment and food and estimating the occurrence). The role that analytical techniques play was analyzed. In both cases, the application of generic solvent extraction and solid-phase extraction (SPE) clean-up, followed by liquid or gas chromatography coupled to mass spectrometry, is decisive. Advances within the analytical techniques have played an unquestionable role.

CONCLUSIONS

All these studies have contributed to an important advance in the knowledge of analytical techniques for the detection of pesticide levels and the subsequent assessment of nonoccupational human exposure.

Pesticide residues and health risk appraisal of tomato cultivated in greenhouse from the Mediterranean region of Turkey

This research aims at assessing the health risks associated with pesticide residues in greenhouse grown tomato production in the Mediterranean Region of Turkey. A multiresidue method based on modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) was used for sample preparation that is applied for pesticide detection from extraction of tomato samples in the methodology generated by The Association of Official Analytical Chemists (AOAC) Official Method. The restrain of the quantification varied from 0.002 to 0.009 mg kg-1. The validated data exposed both adequate recoveries, repeatability and reproducibility, including accomplished all other requirements of the European DG SANTE/12682/2019 Guideline. This study divulges that tomatoes cultivated in greenhouse demonstrate 61.5% of samples with one or various pesticide residues. The maximum permitted residue level of above the EU DG Guideline was in 12.2% of the samples. The main determined pesticide residues on the tomatoes cultivated in greenhouse were identified as chlorpyrifos methyl, cyfluthrin, deltamethrin, and acetamiprid. Chlorpyrifos methyl (9.5%), cyfluthrin (6.6%), deltamethrin (5.5%), and acetamiprid (3.2%) were recognized as the most conducing residues to the hazard index (HI). The HI was 9.5% for adults and 11.02% for children (3 to <10 years). The major contributor of the HI was chlorpyrifos in both.

Dynamics of the Degradation of Acetyl-CoA Carboxylase Herbicides in Vegetables

(1) Background: Aryloxyphenoxy-propionates and cyclohexanediones are herbicides most widely used in dicot crops worldwide. The main objective of the study was to determine the dynamics of herbicide residues in carrot, lettuce, cauliflower, and onion in order to suggest a low level of residues in harvested vegetables. (2) Methods: Small plot field trials were carried out in four vegetables in the Czech Republic. The samples of vegetables were collected continuously during the growing season. Multiresidue methods for the determination of herbicide residues by LC-MS/MS were used. Non-linear models of degradation of individual herbicides in vegetables were calculated using the exponential decay formula. Action GAP pre-harvest intervals for the 25% and 50% maximum residue limit (MRL) and 10 µg kg⁻¹ limit (baby food) were established for all tested herbicides. (3) Results: The degradation dynamics of fluazifop in carrot, onion, and cauliflower was significantly slower compared to quizalofop and haloxyfop. The highest amount (2796 µg kg⁻¹) of fluazifop residues was detected in cauliflower 11 days after application. No residue of propaquizafop and cycloxydim was detected in any vegetable samples. (4) Conclusions: Aryloxyphenoxy-propionate herbicide (except propaquizafop) could contaminate vegetables easily, especially vegetables with a short growing season. Vegetables treated with fluazifop are not suitable for baby food. Lettuce and cauliflower treated by quizalofop are not suitable for baby food, but in onion and carrot, quizalofop could be used. Propaquizafop and cycloxydim are prospective herbicides for non-residual (baby food) vegetable production.