Effect of ultrasound assisted cleaning on pesticide removal and quality characteristics of Vitis vinifera leaves

The fingerprint of pesticides in agricultural used polyethylene

The widespread use of polyethylene (PE) materials in agriculture through mulch films, tunnels, greenhouse covers, irrigation pipes and tying tapes has been instrumental in increasing crop productivity and reducing water demand. However, it raised concerns regarding the interaction between PE and pesticides sprayed on crops. This research strives to study the fingerprint of pesticides in agricultural PE by analyzing new items, end-of-life agricultural plastics and a range of samples corresponding to the recycling of aged PE, from sized and washed flakes to second-hand pellets and plant protection tubes elaborated from recycled plastic. Total concentrations determined for a selection of fungicides and insecticides in the abovementioned materials varied between 4.7 ng g-1 and 4179 ng g-1, with the fungicides cyprodinil and difenoconazole showing the highest concentrations. Furthermore, transformation products of pesticides phased out more than 40 years ago, e.g., p,p'-DDE, were found in some PE items. The survival of pesticides at temperatures above the melting point of this polymer was confirmed in laboratory-scale melting experiments, as well as through the analysis of second-hand pellets. Experiments carried out using pesticide-polluted dripline pipes confirmed the migration of these compounds from PE to flowing water.

Integrating processing factors and large-scale cabbage cultivation to understand the fate tendency and health risks of tolfenpyrad using deterministic and probabilistic models

Understanding the negative effects of agrochemicals on the environment and human health is indispensable for achieving green agriculture. In this study, the optimized UHPLC-MS/MS method achieved a highly sensitive quantification of tolfenpyrad in cabbage within 4.04 min. The occurrence, dissipation, and concentration variation of tolfenpyrad were reflected by the initial deposition of 0.250-2.045 mg/kg, half-lives (T1/2) of 2.4-10.2 d, and terminal magnitudes within 1.134 mg/kg. Furthermore, the fates of tolfenpyrad during processing were elucidated, with processing factors (Pfs) of 0.561-1.282. Among the different processing procedures, soaking in tap water (25 °C) for 5 min removed 43.9 % of tolfenpyrad and was recommended for initial processing. The multidimensional dietary assessment revealed unacceptable levels of short-term risks from tolfenpyrad in children (%ARfD, 160.519-688.725 %) using deterministic and probabilistic models. Fortunately, the risks were minimized to negligible levels (%ARfD, 69.665-98.719 %) through washing and heat processing. Despite the long-term risks (%ADI, 3.310-9.371 %) being within the safety threshold, the cumulative effect of tolfenpyrad in multiple crops (%ADIt, 46.407-121.472 %) and regional differences (p < 0.05) should be emphasized. Our investigation shed light on the fates of tolfenpyrad in raw to processed cabbage with the aim of achieving sustainable agriculture and alerting to the agricultural pollutant's danger to children.

Balancing Health and Sustainability: Assessing the Benefits of Plant-Based Diets and the Risk of Pesticide Residues

The increased consumption of fruit and vegetables is essential for moving towards a healthier and more sustainable diet. Vegetarian diets are gaining in popularity due to their environmental and health implications; however, there is a need for additional research investigating pesticide residues in these foods. It is increasingly recognized that the global food system must prioritize nutritional quality, health, and environmental impact over quantity. Food contaminants, including pesticides, mycotoxins, and heavy metals, pose a substantial threat to food safety due to their persistent nature and harmful effects. We conducted a literature search utilizing four distinct databases (PubMed, Google Scholar, NIH, ScienceDirect) and several combinations of keywords (pesticides, food, vegetarian diet, toxicity, sustainable, removal). Consequently, we selected recent and relevant studies for the proposed topic. We have incorporated articles that discuss pesticide residues in food items, particularly in plant-based products. This study rigorously analyzes the harmful environmental impacts of pesticides and ultimately provides sustainable solutions for their elimination or reduction, along with environmentally sound alternatives to pesticide use. This study concludes that the transition towards sustainable agriculture and food production is essential for reducing pesticide residues in food, thereby protecting human health, wildlife populations, and the environment. This paper argues for the urgent need to transform global food systems to prioritize health and sustainability.

Photocatalytic degradation of the pesticide pyridaben: Identification of degradation pathways using SERS and GC-MS

Degradation pathways of the pesticide pyridaben in tea caused by ultraviolet photocatalytic degradation were identified using SERS and GC-MS. Pyridaben in tea decreased from 4.50 mg/kg to 3.46 mg/kg after 2 h and to 0.62 mg/kg after 5 h, with a degradation rate of 86.22 % and a recovery rate of 90.00 %. The pyridaben degradation process involved C-S cleavage, with a SERS band of ν(C-S) at 710 cm-1 disappearing in the first hour. This was followed by cleavage of the N atom and the attached tert butyl group, resulting in the cleavage of the C-N bond in the ring, causing ring opening degradation. The presence of residual pyridaben was not necessarily related to the content of tea polyphenols; however, the UV light significantly reduced the content of theobromine, EGC, EC, and ECG but increased the content of EGCG. Ultraviolet irradiation slightly reduced the moisture content of oolong tea samples and did not significantly affect the total ash content. The content of water extract increaseing irradiation time due to the influence of moisture. UV irradiation time at the range of 60-360 min could degrade pyridaben while reducing its impact on tea quality.

Pesticide pollution: toxicity, sources and advanced remediation approaches

The Food and Agricultural Organization of the United Nations (FAO) estimates that food production must rise by 70% to meet the demands of an additional 2.3 billion people by 2050. This forecast underscores the persistent reliance on pesticides, making it essential to assess their toxicity and develop effective remediation strategies. Given the widespread utilisation of pesticides, it requires an urgent need to evaluate their toxicity and explore feasible remediation approaches for their removal. Hence, this review provides an overview of the latest information on the presence, distribution, sources, fate, and trends of pesticides in global environmental matrices, emphasizing the ecological and health risks posed by pesticide pollution. Currently, the dominant remediation techniques encompass physical, chemical, and biological methods, yet studies focusing on advanced remediation techniques remain limited. This review critically evaluates both newer and traditional approaches to pesticide removal, offering a descriptive and analytical comparison of various methods. The selection of the appropriate treatment method depends largely on the nature of the pesticide and the effectiveness of the chosen technique. In many cases, technologies such as membrane bioreactors and the fenton process could be integrated with biological technologies to enhance performance and overcome limitations. The study concludes that a hybrid approach combining various remediation strategies offers the most effective and sustainable solution for pesticide removal. Finally, the review underscores the need for further scientific investigation into the most viable technologies while discussing the challenges and prospects of developing safe, reliable, cost-effective, and eco-friendly methods for removing pesticides from the environment.

Prandtl and Ohnesorge numbers dependent of ultrasonic horn energy in Newtonian liquid under batch and continuous flow

The level of knowledge on the non-thermal contribution of ultrasonic wave's energy to perform physico-chemical phenomena is one of the bottlenecks for the commercialization purposes. Under constant nominal power of transducer (Pn), the input electrical power (Pin) is less and sensitive to the medium's physical properties. This study attempts to assess the conversion of acoustic to thermal power experimentally and numerically using COMSOL Multiphysis@ for a 24 kHz horn-type sonicator through a medium without any sono-chemical effect. Single- and homogeneous two-phase Newtonian mixtures of sunflower oil and water (o/w) with a relatively wide range of density (914-998 kg/m3) and viscosity (0.5-63.5 mPa.s) were irradiated in a lab-scale vessel (1 L) under batch and continuous flow configuration. The direct influence of Pn (80-400 W) and o/w ratio (0-1) on temperature rise and subsequent thermo-physical properties of liquid and the indirect influence on Pin and thermal energy conversion (TEC) were investigated employing calorimetric method. A new engineering concept including a power factor correlation was proposed and validated for prediction of Pin as a function of liquid space velocity (ϑ), temperature, Prandtl (Pr) and Ohnesorge (Oh) dimensionless groups. The results showed that under constant temperature and Pn, increasing Pr and Oh increased Pin with a similar trend for both modes of operation. An increase in temperature directly led to a decrease in Pin with a power factor closed to "-1". The Pin in continuous flow was higher compared to batch configuration at similar temperature, liquid properties, and Pn. This effect was more significant with increasing ϑ. An increase in ϑ at constant Pn led to a decrease in the inlet/outlet temperature difference in continuous flow and an increase in Pin. Increasing Pn resulted in higher TEC for both configurations; however, TEC was relatively lower in continuous flow than batch configuration indicating more efficient sonication in continuous flow.

From field to table: Ensuring food safety by reducing pesticide residues in food

The present review addresses the significance of lowering pesticide residue levels in food items because of their harmful impacts on human health, wildlife populations, and the environment. It draws attention to the possible health risks-acute and chronic poisoning, cancer, unfavorable effects on reproduction, and harm to the brain or immunological systems-that come with pesticide exposure. Numerous traditional and cutting-edge methods, such as washing, blanching, peeling, thermal treatments, alkaline electrolyzed water washing, cold plasma, ultrasonic cleaning, ozone treatment, and enzymatic treatment, have been proposed to reduce pesticide residues in food products. It highlights the necessity of a paradigm change in crop protection and agri-food production on a global scale. It offers opportunities to guarantee food safety through the mitigation of pesticide residues in food. The review concludes that the first step in reducing worries about the negative effects of pesticides is to implement regulatory measures to regulate their use. In order to lower the exposure to dietary pesticides, the present review also emphasizes the significance of precision agricultural practices and integrated pest management techniques. The advanced approaches covered in this review present viable options along with traditional methods and possess the potential to lower pesticide residues in food items without sacrificing quality. It can be concluded from the present review that a paradigm shift towards sustainable agriculture and food production is essential to minimize pesticide residues in food, safeguarding human health, wildlife populations, and the environment. Furthermore, there is a need to refine the conventional methods of pesticide removal from food items along with the development of modern techniques.

Exploring viscosity influence mechanisms on coating removal: Insights from single cavitation bubble behaviours in low-frequency ultrasonic settings

The role of acoustic cavitation in various surface cleaning disciplines is important. However, the physical mechanisms underlying acoustic cavitation-induced surface cleansing are poorly understood. This is due to the combination of microscopic and ultrashort timescales associated with the dynamics of acoustic cavitation bubbles. Here, we have precisely controlled single-bubble cavitation in both space and time. Ultrasonic excitation leads to the cavitation of generated single bubbles. A synchronous ultrafast photomicrographic system simultaneously records the dynamics of single acoustic cavitation bubbles (SACBs) and the cleaning process of the nearby surface in liquids with varying viscosities. Finally, we analysed the correlation between bubble dynamics and surface cleaning situations. The differences in the typical dynamic characteristics of the bubbles during collapse in liquids with varying viscosities reveal two main mechanisms underlying surface cleaning by acoustic cavitation, which are respective the Laplace pressure during the bubble's movement and liquid jets during bubble collapse. Our study provides a better physical understanding of the ultrasonic cleaning process based on acoustic cavitation, and will help to optimize and facilitate the applications of surface cleaning, especially for the cleaning of substrates with tightly attached dirt.

Sono-processes: Emerging systems and their applicability within the (bio-)medical field

Sonochemistry, although established in various fields, is still an emerging field finding new effects of ultrasound on chemical systems and are of particular interest for the biomedical field. This interdisciplinary area of research explores the use of acoustic waves with frequencies ranging from 20 kHz to 1 MHz to induce physical and chemical changes. By subjecting liquids to ultrasonic waves, sonochemistry has demonstrated the ability to accelerate reaction rates, alter chemical reaction pathways, and change physical properties of the system while operating under mild reaction conditions. It has found its way into diverse industries including food processing, pharmaceuticals, material science, and environmental remediation. This review provides an overview of the principles, advancements, and applications of sonochemistry with a particular focus on the domain of (bio-)medicine. Despite the numerous benefits sonochemistry has to offer, most of the research in the (bio-)medical field remains in the laboratory stage. Translation of these systems into clinical practice is complex as parameters used for medical ultrasound are limited and toxic side effects must be minimized in order to meet regulatory approval. However, directing attention towards the applicability of the system in clinical practice from the early stages of research holds significant potential to further amplify the role of sonochemistry in clinical applications.