Unwanted Residues Research Articles

Analysis of Food Safety Import Notifications and Relevant Standards and Regulations for Aquaculture Products With a Focus on Antimicrobial Residues and Use

The use of antimicrobials is essential for the aquaculture sector; however, their misuse is cause for concern because it could adversely affect the environment and human health. Irresponsible use of antimicrobials can lead to antimicrobial resistance and result in the presence of unwanted residues in aquaculture products. The establishment of maximum residue limits (MRLs) for antimicrobials is of great importance for monitoring their correct use, but the lack of harmonized standards as well as the regulatory gaps for the aquatic products create a challenging situation, as it is reflected in import notifications related to food safety. This paper collects information about current MRLs for antimicrobials in aquatic commodities in the main importing and exporting countries of aquatic products and compares them with each other and with MRLs set by Codex Alimentarius. This analysis highlighted the need for Codex Alimentarius guidance regarding MRLs for nine antimicrobials in aquaculture products (chlortetracycline, doxycycline, enrofloxacin, erythromycin, florfenicol, sulfadimethoxine + ormetoprim, sulfamerazine, tetracycline, and trimethoprim). This paper shows that there is still work to do to implement exhaustive science‐based international standards for residues permitted in aquatic commodities and promote harmonization.

Electrochemistry of copper post-CMP cleaning examined in combination with brush-scrubbing in a malonic acid solution

Post-CMP cleaning (PCMPC) is used in the fabrication of integrated circuits to remove unwanted residues of chemical mechanical planarization (CMP) from wafer surfaces. PCMPC combines (electro)chemical surface reactions in a cleaning solution with mechanical scrubbing by a brush. Using tribo-electrochemical protocols, the present work simultaneously probes the (electro)chemical and mechanical functions of PCMPC and determines the corresponding cleaning efficiency. Employing malonic acid as a cost effective, environmentally compatible cleaning solution for copper, it is demonstrated how this electroanalytical approach can facilitate the tasks of developing and evaluating effective PCMPC solutions. The results indicate that malonic acid in a pH neutral environment removes Cu-oxides and their co-adsorbed organic residues of CMP. A detailed electrochemical procedure is illustrated for quantifying the residue removal efficiency of PCMPC, and the role of brush scrubbing in the overall cleaning process is identified.

A CRISPR/Cas9-based vector system enables the fast breeding of selection-marker-free canola with Rcr1-rendered clubroot resistance.

Breeding for disease resistance in major crops is of crucial importance for global food security and sustainability. However, common biotechnologies such as traditional transgenesis or genome editing do not provide an ideal solution, whereas transgenic crops free of selection markers such as cisgenic/intragenic crops might be suitable. In this study, after cloning and functional verification of the Rcr1 gene for resistance to clubroot (Plasmodiophora brassicae), we confirmed that the genes Rcr1, Rcr2, Rcr4, and CRa from Brassica rapa crops and the resistance gene from B. napus oilseed rape cv. 'Mendel' on chromosome A03 were identical in their coding regions. We also determined that Rcr1 has a wide distribution in Brassica breeding materials and renders potent resistance against multiple representative clubroot strains in Canada. We then modified a CRISPR/Cas9-based cisgenic vector system and found that it enabled the fast breeding of selection-marker-free transgenic crops with add-on traits, with selection-marker-free canola (B. napus) germplasms with Rcr1-rendered stable resistance to clubroot disease being successfully developed within 2 years. In the B. napus background, the intragenic vector system was able to remove unwanted residue sequences from the final product with high editing efficiency, and off-target mutations were not detected. Our study demonstrates the potential of applying this breeding strategy to other crops that can be transformed by Agrobacterium. Following the streamlined working procedure, intragenic germplasms can be developed within two generations, which could significantly reduce the breeding time and labor compared to traditional introgression whilst still achieving comparable or even better breeding results.

Evaluation of the acute toxicity by Artemia salina of hydroxyapatite nanoparticles obtained via sol-gel in an aqueous medium without using additives

Hydroxyapatite (Hap) is one of the most important calcium phosphate bioceramics applied to bone tissue regeneration. Synthesizing Hap nanoparticles from easily accessible and low-cost alternative sources of calcium precursors remains a challenge, as well as defining an ideal and reproducible synthesis route without using additives to control the pH of the reaction and entirely performed at room temperature. This study proposes a route for the synthesis of hydroxyapatite by the sol-gel method without the addition of additives for pH control, carried out at room temperature. The Hap samples were characterized by FTIR, XRD, SEM, and BET. The synthesized Hap presented a spherical morphology without the formation of unwanted phases or residues. Samples calcined at 600 and 750 °C resulted in stoichiometric hydroxyapatite with 100% purity and average particle sizes of 24 and 53 nm, respectively. On the other hand, the samples calcined at 900 and 1050 °C presented a specific content of β-calcium phosphate and average particle sizes of 118 and 732 nm, respectively. Acute toxicity was evaluated by Artemia salina nauplii instar I and II for 24 and 48 h of exposure. The tests were conducted on 10, 100, and 1000 ppm of Hap dissolutions. The highest death rate and more significant morphological alterations were observed in A. salina nauplii instar II, exposed to Hap at a concentration of 1000 ppm for 48 h.

Analytical and numerical characterisation of terminal velocities of Tenebrio molitor larvae in a new, asymmetrical zigzag based separation system

Abstract Separation of Tenebrio molitor larvae from unwanted residues, like frass, feed or exuviae is a key process step for an industrial scale plant. One method to separate larvae from residues is using a zigzag air classifier. For designing and for an efficient operation of a zigzag air classifier, the terminal velocity is a key parameter to separate larvae from different residues with a high separation sensitivity. In this work, the terminal velocities of different larvae sizes are evaluated analytically, numerically and experimentally. For this, the sizes of 3 week to 12 week old larvae were used to calculate and simulate the terminal velocity. To validate the results, an experiment was carried out and compared with the analytical and numerical data. For this, a model for T. molitor larvae was designed to calculate the surface and volume of a larva to produce equivalent spheres with the same physical properties as a real larva. The results are showing similar curves with terminal velocities from 5 m/s for young larvae (3 weeks old) to 12 m/s for older larvae (12 weeks old). The deviations between each method are 1 m/s for smaller larvae and 1.5 m/s for bigger larvae. In further experiments and simulations, approaches with calculation methods for non-spherical particles are necessary to achieve results closer to reality due to the cylindrical shape of T. molitor larvae.

Bioaccumulation of pesticides in fish resulting toxicities in humans through food chain and forensic aspects.

A crucial component for agricultural productivity is pesticide application. Increased usage of pesticides has significantly increased agricultural output, reduced grain losses in storage, and overall enhanced human wellbeing. Globally, every year approximately 3 billion kg of pesticides are used which budgets around 40 billion USD. Pesticide use can leave behind unwanted residues that can contaminate food, the environment, and living tissues. They are known to spread from agricultural regions that have been treated into the wider environment, where they affect non-target creatures. All tiers of biological organisms, directly impacted by this exposure. Pesticides at sub-lethal levels alter every aspect of a fish's physiology, including histology, haematology, defence mechanisms, and behaviour. The same topic of pesticide toxicology is the emphasis of this article, which also addresses some important induced chronic toxicological effects of pesticides in fish and the extent of their bioaccumulation in fish tissues. The data represents the largest bodies of water, such as rivers and lakes, that have been contaminated by pesticides, notably due to pesticide drift. It has been discussed how readily pesticides are absorbed into fish bodies and how this enters the food chain inducing harmful impacts on human health when consumed.

Ready Biodegradability study and insights with ultra-high-performance liquid chromatograph coupled to a quadrupole time of flight of a Metformin-based drug and of Metarecod, a natural substance-based medical device.

Drugs are indispensable products with incontrovertible benefits to human health and lifestyle. However, due to their overuse and improper disposal, unwanted residues of active pharmaceutical ingredients (APIs) have been found in different compartments of the environment and now are considered as contaminants of emerging concern (CECs). Therefore, they are very likely to have a boomerang effect on human health, because they can enter into the food cycle. In the current legislation framework, one of the tests first used to evaluate biodegradation of APIs as well as chemical compounds is the ready biodegradability test (RBT). This test can be performed according to a series of protocols prepared by Organization for Economic Co-operation and Development (OECD) and usually is carried out on pure compounds. RBTs, largely used due to their relatively low cost, perceived standardization, and straightforward implementation and interpretation, are known to have a number of well-documented limitations. In this work, following a recently reported approach, we propose to improve the evaluation of the RBT results applying advanced analytical techniques based on mass spectrometry, not only to the APIs but also to complex formulated products, as the biodegradability can potentially be affected by the formulation. We evaluated the ready biodegradability of two therapeutic products, Product A-a drug based on Metformin-and Product B-Metarecod a natural substance-based medical device-through the acquisition of the fingerprint by ultra-high-performance chromatograph coupled to a quadrupole time of flight (UHPLC-qToF) of samples coming from the RBT OECD 301F. Untargeted and targeted evaluation confirmed the different behavior of the two products during the respirometry-manometric test, which showed a difficulty of the Metformin-based drug to come back in the life cycle, whereas Metarecod resulted ready biodegradable. The positive results of this research will hopefully be useful in the future for a better evaluation of the risk/benefit ratio of APIs extended to the environment.

Colorimetric mercury detection with enhanced sensitivity using magnetic-Au hybrid nanoparticles.

Due to the neural toxicity of mercury, there is a need for the development of on-site detection systems for Hg2+ monitoring. To this end, a new colorimetric mercury detection probe, Fe3O4@SiO2@Au (magnetic-Au; Mag-Au) hybrid nanoparticles, has been developed. The Au on the surface of Mag-Au is an indicator of Hg2+, which forms an AuHg alloy (amalgam) on their surface (Mag-Au@Hg), with excellent peroxidase-like activity. The oxidation of 3,3',5,5'-tetramethylbenzidine by Mag-Au@Hg resulted in a color change of the indicator solution, which was enhanced with increasing Hg2+ concentration. Mag-Au can be used to detect Hg2+ at nanomolar concentrations. Additionally, magnetic separation can be used to easily purify and concentrate the Mag-Au@Hg from samples, and thus avoid interference from unwanted residues or colored samples. The feasibility of Mag-Au for Hg2+ detection was tested with an artificial urine solution and it can be used to detect Hg2+ in various real samples, such as river water, seawater, food, and biological samples.

Automated path selection technique while incorporating multiple assay operations and cross-contamination avoidance in cross-referencing DMFBs

Digital Microfluidic Biochips (DMFBs) perform many biochemical reactions requiring relatively less cost and very less amount of space. DMFBs that use cross-referencing addressing requires less number of pins, therefore, less manufacturing cost. However, it suffers from a problem called electrode interference, i.e., unwanted droplet operation because of an extra activated cell. DMFBs also suffer from a problem called cross-contamination, i.e., mixing of droplets with unwanted residues of droplets containing different chemicals which results in incorrect diagnosis. In this article, our objective is whether a cross-referencing DMFB with an efficient module placement design can be declared as a multifunctional chip or not. We propose a chip design which incorporates parallelism for enhancing performance in terms of assay completion time while performing multiple types of bioassays. We also propose a novel method, which automatically selects a new cross-contamination free path while routing from the source to the sink. We have included an on-chip washing scheme. The whole method ensures no Electrode Interference.

In silico analysis of quercetin, gallic acid, oleanolic acid, and ursolic acid on diabetes mellitus

Objective: Diabetes is a disease that occurs due to pancreatic β cells failing to produce enough insulin or the inability to use the produced insulin effectively in the body. According to the data of the IDF diabetes atlas, it has been reported that there are 537 million diabetic patients aged 20-79 worldwide in 2021 and this number is expected to reach 643 million in 2030 and 783 million in 2045. To control diabetes at such a severe level, scientists are trying to find various treatment methods. One of them is natural treatments. In this study, the affinity values of quercetin, gallic acid, oleanolic acid and ursolic acid, which have antidiabetic properties, to diabetes-related renin, cathepsin-d, T-PA, leptin, MASP-2, FABP4 proteins were investigated. Methods: For molecular docking analysis, unwanted residues and chains were deleted from the proteins with UCSF Chimera 1.15 software and prepared for docking by adding polar hydrogen atoms. Next, quercetin, gallic acid, oleanolic acid and ursolic acid used as ligands were brought to minimum energy conformation. Protein and ligands prepared for molecular docking were analyzed with Autodock Tools 1.5.6 software. Molecular docking results were viewed with BIOVIA Discovery Studio and protein plus software. Moreover, pkCSM software was used for ADME analysis. Conclusion: As a result, quercetin was found to be more effective than the other three flavonoids.

APLIKASI MULTI BANK SAMPAH BERBASIS WEB

Material waste is unwanted residue after the end of a process. Waste reduction activities aim to make all levels of society, including the government, the business world and the wider community able to carry out activities to reduce, reuse, recycle (3R) through smart, efficient and programmatic efforts. The best solution to this problem is a waste bank. Waste Bank is a place for sorting and collecting waste that can be recycled and reused which has economic value. Waste bank work mechanisms such as sorting waste, submitting waste to waste banks, weighing waste, recording, selling the delivered waste are entered into a savings book and revenue sharing for the sale of waste between savers and implementers.The multi waste bank information system can help the waste bank work.The multi waste bank information system can be used by the waste bank for the publication of the location of the waste bank, data collection of waste bank customers, recording and archiving customer transaction data and helping the waste bank to find customers with the online customer registration feature. The multi waste bank information system is built on a web basis using the laravel framework. The method applied in the development of a multi bank waste information system uses the waterfall model. The multi waste bank information system has been successfully built by testing the system's functionality using black box testing and expert judgement. The results that the system can function according to user expectations and needs.

Hormones residues in bovine animals: Sampling, analysis and health risk assessment

The use of hormones for breeding animal livestock has been banned since 1981 under the Council Directive 81/602/EC. So far, each country should monitor the use of anabolic hormones in animal production to protect the consumer's health against these unwanted residues. This paper presents the research results on steroid and non-steroid hormones residues carried out in Lebanon from 2018 to 2020. Using a newly developed and validated LC-MS/MS method, the detection and the quantification of hormones in bovine matrices were done. The targeted matrices were muscle, liver, kidney, and bile. A total of two-hundred and forty-seven samples were collected from different slaughterhouses located in six different cities in Lebanon. Interestingly, only four hormones were found: testosterone, progesterone, epitestosterone, and 6 propyl 2thiouracil. Based on the obtained data, the estimated daily intake, hazard quotient, and hazard index were calculated to evaluate an exposure assessment.

ELETROCOAGULAÇÃO/ELETROFLOCULAÇÃO PARA TRATAMENTO DE ÁGUAS RESIDUÁRIAS: ELETRODOS NÃO CONVENCIONAIS E ACOPLAMENTO DE TÉCNICAS

ELECTROCOAGULATION/ELECTROFLOCULATION FOR WASTEWATER TREATMENT: NON-CONVENTIONAL ELECTRODES AND COUPLING OF TECHNIQUES. Electrocoagulation-electroflotation (EC) technology is a well-known wastewater treatment process that consists of applying electric current to remove contaminants without requiring the addition of chemicals that can generate secondary pollutants. Once they are the most widely used, iron and aluminum electrodes are considered conventional, however they leave unwanted residues, which will give a yellowish-brown color to the treated water, in the case of iron electrodes, and are associated with potential risks to human health, in the case of aluminum electrodes. In this regard, the study of non-conventional electrodes capable of circumventing those problems is essential for the development of more effective wastewater treatments. In this review article, a brief presentation will be made of the history of electrofloculation followed by a brief discussion of conventional electrodes and the mechanisms that govern the processes of removing contaminants by the electrocoagulation process. Subsequently, the non-conventional electrodes reported in the literature up to the present moment will be presented, as well as their potential, applications and performance when applied in water treatment. Finally, will be discussed the coupling of the electroflotation with other water treatment techniques towards achieving a better-quality reuse water.

Impact of the insecticide 14C-chlorfenvinphos in a terrestrial ecosystem

Pesticides are an essential component of agricultural production. The increased use of pesticides greatly aided agricultural production, reduced stored grain losses, and improved human well-being in general. However, the use of pesticides may lead to unwanted residues such as traces of pollutants from food, the environment and living tissues. The environmental fate of 14C- chlorfenvinphos was studied using an agricultural ecosystem that included soil, plants, beetles, earthworms and one type of common bird in Egypt (Asfour Baladi). This study was conducted on a restricted field area that was cultivated with maize plants as target crop and soybean plants as an alternate crop. The residue level in soybean seeds was almost 6 times higher than in dry maize seeds. The high concentration of 14C- residues in beetles (1.28µg/g) was observed on day 26 after spraying 14C- chlorfenvinphos and decreased thereafter. The earthworms, on the other hand, showed a progressive increase with time and its maximum residue was detected after 75 days (3.25µg/g) .The dead birds showed the highest concentration of residues in the brain, liver and heart as compared with alive birds in the ecosystem. The chromatographic analysis indicated the presence of the parent compound in addition to three degradation products especially in dry seeds and soil.

(Invited) CMP Market and Technology Trends for 2021

The technology of chemical mechanical polishing (CMP) continues to evolve in multiple dimensions. As one of the key enabling processes for advanced digital devices, such as microprocessors and high-speed memory, CMP is expected to deliver surfaces that are planarized flat and smooth to insanely small dimensions (below 3 nm) while also avoiding even the smallest micro-scratches and without leaving a trace of unwanted residue. These applications also involve tuning the selectivity between two or more different materials to enable topography control at the nanoscale level. CMP also plays a key role in many other emerging markets, such as certain MEMS devices, SiC substrates for power devices, and many more. Examples and information from numerous sources will be combined to provide a wide view of the CMP market and to highlight several trends which have both technical and commercial implications for the near future.

Thermal plasma activation and UV/H2O2 oxidative degradation of pharmaceutical residues

The aquatic environment becomes increasingly contaminated by anthropogenic pollutants such as pharmaceutical residues. Due to poor biodegradation and continuous discharge of persistent compounds in sewage water samples, pharmaceutical residues might end up in surface waters when not removed. To minimize this pollution, onsite wastewater treatment techniques might complement conventional waste water treatment plants (WWTPs). Advanced oxidation processes are useful techniques, since reactive oxygen species (ROS) are used for the degradation of unwanted medicine residues. In this paper we have studied the advanced oxidation in a controlled laboratory setting using thermal plasma and UV/H2O2 treatment. Five different matrices, Milli-Q water, tap water, synthetic urine, diluted urine and synthetic sewage water were spiked with 14 pharmaceuticals with a concentration of 5 μg/L. All compounds were reduced or completely decomposed by both 150 W thermal plasma and UV/H2O2 treatment. Additionally, also hospital sewage water was tested. First the concentrations of 10 pharmaceutical residues were determined by liquid chromatography mass spectrometry (LC-MS/MS). The pharmaceutical concentration ranged from 0.08 up to 2400 μg/L. With the application of 150 W thermal plasma or UV/H2O2, it was found that overall pharmaceutical degradation in hospital sewage water were nearly equivalent to the results obtained in the synthetic sewage water. However, based on the chemical abatement kinetics it was demonstrated that the degree of degradation decreases with increasing matrix complexity. Since reactive oxygen and nitrogen species (RONS) are continuously produced, thermal plasma treatment has the advantage over UV/H2O2 treatment.

Pixel domain multi-resolution minimum variance in-painting of CMB maps

This work introduces an unbiased minimum variance in-painting of the pixel domain CMB maps for both the missing and available sky regions. In the missing region, it generates CMB realizations that have identical statistical properties to the expected CMB signal; and in the available region, it significantly alleviate the unwanted residuals, e.g., the residual of EB-leakage. The time cost of this method follows ∼ O(Nside3) (Nside is the map resolution parameter), which is similar to the fast spherical harmonic transforms and is much better than the traditional minimum variance method that follows ∼O(Nside6). This method is the basis of a series of minimum variance estimations for analyzing CMB datasets, and more works based on it will follow in the future.

Microalgae in a global world: New solutions for old problems?

The human population blast has brought several problems related with the overconsumption of a wide range of feedstocks and natural resources conducting to their risk of depletion. The consumption of fossil fuels is an example, with increasing levels of exploitation and negative impacts caused by their use. Anthropogenic activities have triggered the over accumulation of many hazardous substances and wastes which are regarded to be detrimental to life in the Earth and to the various planet ecosystems. There is an urgent need to restore natural resources and unwanted residues and wastes to levels prior the demographic explosion. Microalgal biotechnology appears to be pivotal to achieve this goal in a near future to come. This review presents the current resource problems affecting the Earth and how microalgae are expected to be an important part of the solution, discussing how the production of renewable energy from microalgae can help in an integrated way to mitigate different environmental problems. Microalgae are able to convert wastewaters, CO2 and organic residues in marketable biomass for different uses, including biofuels, converting waste in value. An inventory of current microalgal-based biorefineries in operation as well as a directory of companies, products and applications are also presented.

Ülkemizde yetiştirilen bazı fasulye çeşitlerinin Pseudocercospora griseola (Sacc.) Crous & U. Braun’dan kaynaklanan Fasulye köşeli yaprak lekesi hastalığına karşı reaksiyonları

Vegetable bean production as mid-season crops in greenhouses has increased in two provinces, Bartın and Zonguldak, in the Western Black Sea region. Green bean is sown in about half of the total area of 510.000 da in this region. Angular leaf spot disease caused by Pseudocercospora griseola has been a serious disease for the last five years and it is so widespread in the region, showing almost 100% incidence. Since the beans are used for fresh consumption and are harvested continuously, fungicide use is restricted due to unwanted residues. Because of the farmers in the region widely use two local cultivars susceptible to the disease, providing resistant cultivars for farmers was the aim of this study. Although the causal agent has great pathogenic variation, determination of pathotypes of the P. griseola was not succeed since the three of the differential cultivars did not produced seed in two tested regions of Turkey. For this reason seventeen common bean cultivars in Turkey were selected and their reactions against ten randomly selected the most aggressive isolates of P. griseola were used for screening resistance. Two bush type bean cultivars, Bourgondia and Yalova 17, out of nine showed resistant reaction against all of ten isolates while three climbing types, Fabio, Burayşe and Selvi, out of eight were found resistant against all of the isolates of P. griseola. All of these resistant cultivars have good culinary characteristics.

Evaluation of Pesticide Residue Dynamics in Lettuce, Onion, Leek, Carrot and Parsley.

The dynamics of 32 active substances contained in pesticide formulations (15 fungicides and 17 insecticides) were analyzed in iceberg lettuce, onion, leek, carrot, and parsley. Pesticide residues were monitored from the time of application until harvest. In total, 114 mathematical models of residue dissipation were developed using a first-order kinetic equation. Based on these models, it was possible to predict the action pre-harvest interval (the time between the last pesticide application and crop harvest) needed to attain a targeted action threshold (value significantly lower than the maximum limit) for low-residue vegetable production. In addition, it was possible to determine an action pre-harvest interval based on an action threshold of 0.01 mg kg−1 to produce vegetables intended for zero-residue production. The highest amount of pesticide residues were found in carrot and parsley leaves several days after treatment, and pesticide dissipation was generally slow. Lower amounts were found in leeks and lettuce, but pesticide dissipation was faster in lettuce. According to our findings, it seems feasible to apply reduced pesticide amounts to stay below unwanted residue levels. However, understanding the effectivity of reduced pesticide application for controlling relevant pest organisms requires further research.