Fortification Levels Research Articles

Determination and Quantification of Folpet in Barley using HPLC-DAD Analysis

Although rоutinе pesticide analysеs are mostly performed using GC-MS, GC-MS/MS and/or LC-MS/MS, some pesticides especially those with relatively high MRLs and good detector response could also be precisely quantified with less sensitive equipment which gives the opportunity to some laboratories to expand their scope of work. The study focuses on HPLC-DAD method development for detection of folpet in barley grain. QuEChERS method was performed for extraction after which, additional clean-up was performed using PSA and polypropylene filtration. Pesticide separation was achieved using mobile phase of acidified CAN (pH 2.5) and water. The initial mobile phase was 60:40% (v/v), the elution gradient starts from 80:20% (v/v) to 100:0% (v/v) in 7 min and holds 100:0% (v/v) up to 8.5 min at a flow rate of 1 ml/min after which in the next 6.5 min the column was re-equilibrated to 40% phase-B. Calibration was performed using matrix-matched calibration standards. The obtained limits of detection (LOD) and quantification (LOQ) were 0.18 and 0.55 mg/kg, respectively, and the linear regression coefficient was 0.9973. Recovery, repeatability and reproducibility were investigated at three fortification levels (0.1 mg/kg, 0.6 mg/kg, and 1.6 mg/kg) and were found acceptable with relative standard deviation less than 10%. The method was applied for the analysis of three barley grain samples obtained from different producers and showed that folpet was present in one sample below the LOQ. Overall, the developed method is suitable for the determination of folpet in barley grains at levels below the established MRL of 1 mg/kg.

Incorporating ultrashort-chain compounds into the comprehensive analysis of per- and polyfluorinated substances in potable and non-potable waters by LC-MS/MS

Ultrashort-chain (USC) per- and polyfluoroalkyl substances (PFAS) are small and very polar compounds with carbon chain lengths shorter than C4. Their ubiquitous and high levels of occurrence in environmental aquatic systems are emerging as a significant concern, rivaling the well-established issues associated with long-chain PFAS contamination. Therefore, it is important to analyze both USC and long-chain PFAS together in water samples to comprehensively assess and address the full spectrum of PFAS contamination. The high polarity of USC PFAS poses a challenge for standard chromatographic practices in PFAS analysis, primarily due to insufficient chromatographic retention. In this study, a simple and reliable workflow was developed for the simultaneous analysis of C1 to C14 perfluoroalkyl carboxylic and sulfonic acids, along with other groups of PFAS, in both potable and non-potable waters. The chromatographic separation was conducted using a polar-embedded reversed-phase LC column with an inert coating on the hardware. Three different water matrices (tap water, bottled water, sewage treatment wastewater) were chosen for method evaluation to demonstrate the applicability of the developed workflow for measuring 45 PFAS compounds in diverse water samples. A dilute-and-shoot workflow was evaluated by accuracy and precision analysis at five fortification levels, ranging from 2 to 250 ng/L. Eighteen isotopically labeled PFAS, serving as extracted internal standards, were added to the samples at 100 ng/L to validate the accuracy of the entire workflow. Calibration standards were prepared in reverse osmosis water due to its cleanliness for all analytes. The calibration ranges varied among different analytes, spanning from 1 – 1000 ng/L. All analytes and extracted internal standards exhibited recovery values ranging from 70% to 130% of the nominal concentration across all fortification levels. Satisfactory method precision was demonstrated with %RSD values below 20%. Additional potable and non-potable waters collected from various source waters were tested to further demonstrate that the established workflow is suitable for the accurate quantification of targeted PFAS in a wide range of water matrices.

Polyphenolic characterization, nutritional and microbiological assessment of newly formulated semolina fresh pasta fortified with grape pomace

The application of an innovative patented technology on grape pomace allowed to obtain a food ingredient no matter the seasonality and with a great shelf-life thanks to its high polyphenolic content. Then, fresh pasta samples fortified with 5 and 10 g/100 g of this innovative ingredient were prepared and their polyphenolic content, nutritional and microbiological assessments were investigated. The two levels of fortification led to an increase of polyphenols content before and after pasta cooking, which resulted in an increased antibacterial activity. Only the fortification with 5 g/100 g of grape pomace powder determined a high level of Slowly Digestible Starch and a low predicted Glycaemic Index, highlighting a possible ‘limit effect’ for the fortification of semolina fresh pasta. Overall, results confirmed that the use of this concentration obtained with the employment of the new technology allowed the production of fresh pasta with better polyphenolic profile and nutritional value even after cooking.

The Potential for Bouillon Fortification to Reduce Dietary Micronutrient Inadequacy: Modeling Analyses Using National Survey Data from Cameroon, Ghana, and Haiti

BackgroundBouillon is commonly consumed in some countries where micronutrient deficiencies are prevalent, but it has not been widely adopted as a micronutrient fortification vehicle. ObjectivesWe modeled the potential impacts of bouillon fortification on dietary micronutrient adequacy to inform future discussions around bouillon fortification programs. MethodsWe analyzed the dietary intake of women of reproductive age (WRA) and 1- to 5-y-old children from a national dietary survey in Cameroon, and “apparent intake” (using the nutrient density approach) of WRA, children, and men from 3 household surveys in Cameroon, Ghana, and Haiti. We examined (apparent) intake of bouillon and simulated the impacts of bouillon fortification with varying levels of vitamin A, folic acid, vitamin B12, iron, and zinc on inadequate intake (below the estimated average requirement) and intake above the tolerable upper intake level (UL). Scenarios accounted for current mandatory fortification programs and different assumptions about iron absorption from bouillon. ResultsBouillon was consumed by >67% of households in Ghana and >90% in Haiti and Cameroon. Median (apparent) consumption ranged from 1.6 to 2.1 g/d for WRA, 0.7 to 1.0 g/d for children, and 1.8 to 2.2 g/d for men. Bouillon fortification at the highest micronutrient concentration modeled was predicted to reduce dietary inadequacy by 21–52 percentage points (pp) for vitamin A; 3–47pp for folic acid, and 4–90pp for vitamin B12, depending on the country and population group. In contrast, predicted impacts for iron were modest (2–17pp reduction) but would increase if absorption of iron from bouillon were enhanced. Simulated zinc fortification reduced inadequacy by 12–50pp, but zinc intake above the UL exceeded 10% among children in almost all scenarios. ConclusionsModeling indicates that bouillon fortification could improve dietary micronutrient adequacy beyond existing fortification programs. Further work is needed to identify fortification levels that meet criteria for nutritional benefit, technical and commercial feasibility, affordability, and cost-effectiveness.

Development of an advanced analytical technique for detecting multiple pesticide residues in vegetables through liquid chromatography tandem mass spectroscopy (LC-MS/MS)

A comprehensive LC-MS/MS method, which employs Positive Electrospray Ionization (PEI) and Multiple Reaction Monitoring (MRM) was developed for the simultaneous determination of 35 pesticides belonging to various chemical classes in tomato, brinjal, chili, and okra samples. Extraction was facilitated using a modified QuEChERS method, which allows efficient sample analysis in a single run. Calibration curves for each pesticide exhibited linearity within the concentration range of 0.0025 to 0.1 µg mL−1, with correlation coefficients ranging from 0.993 to 0.999. Mean recoveries at five fortification levels (0.01 to 0.5 µg kg−1) ranged from 80 to 90%, demonstrating satisfactory precision (RSD < 20%). The matrix effects, mitigated through an optimized cleanup process, were observed within the range of 6.42% to 19.52%. The developed method having the limit of quantification of 0.01 mg kg−1 for all 35 pesticides, proved to be highly sensitive and rapid for multi-residue estimation in diverse vegetable samples. Subsequently, the method was used to analyze the market samples from Varanasi, India, which revealed the presence of pesticides like Chlorpyrifos, Chlorantraniliproleand Indoxacarb in tomato, brinjal, chili and okra. Therefore, the method could be considered as a robust tool for monitoring pesticide residues in vegetables, aiding in quality assessment and regulatory compliance in the agriculture sector.

Development and quality evaluation of a fermented dessert made from donkey milk fortified with oat flour, wheat germ oil, and pomegranate extract

The dairy sector is constantly innovating in response to the critical issues connected to sustainability and healthiness and to the increasing consumer demand for products with nutritional benefits. This study aimed to develop an innovative fermented dessert made from donkey milk (FDMD) added with oat flour (OF) and wheat germ oil (WGO). Different concentrations of OF and WGO (8, 10, and 12, and 3, 5, and 7 % w/w) were tested to optimize texture and, for this purpose, D-optimal mixture design was used. The best structural formulation obtained (11.5% w/w of OF and 3.5% w/w of WGO) was fortified with two further ingredients including dark chocolate 3% w/w, and pomegranate extract rich in ellagic acid (0.5 w/w, FDMD-A, and 1% w/w, FDMD-B) for improving flavor and nutritional properties. The quality and safety characteristics of the product during 30 days of storage were evaluated. The application of the Design of Experiment (DoE) proved successful in achieving the desired structural characteristics using 11.5% w/w OF and 3.5% w/w WGO. The addition of pomegranate extract did not negatively influence the textural and rheological characteristics of the samples, instead acting positively on the stability of the product during storage. Moreover, it had an impact on total polyphenol content and antioxidant activity, showing better results at 1% level of fortification (FDMD-B). The shelf-life study demonstrated that both formulations were microbiologically safe and stable and were appreciated by the panel involved in the sensory analysis. Finally, poor proteolysis took place during the 30-day storage period, indicating that the two samples did not significantly change over the 30 days of storage.

Current Trends in Food Processing By-Products as Sources of High Value-Added Compounds in Food Fortification.

Along the food production chain of animal, fish, and vegetable products, a huge amount of by-products are generated every year. Major nutritional, financial, and environmental advantages can be achieved by transforming them into functional ingredients for food formulation and fortification. In this review, we investigated various conventional and emerging treatments recently employed to obtain functional ingredients rich in proteins, fibers, and bioactive compounds from vegetables, fish, meat, and dairy by-products. The optimal enrichment level in food as well as the nutritional, techno-functional, and sensory properties of the final food were also discussed. Novel technologies such as ultrasounds, microwaves, and high pressure have been successfully adopted to enhance the extraction of target compounds. The functional ingredients, added both in liquid or powder form, were able to improve the nutritional quality and antioxidant potential of food, although high levels of fortification may cause undesired changes in texture and flavor. This review provides important considerations for further industrial scale-up.

Colorimetric detection of Cr(VI) in water using tetramethyl benzidine (TMB) as an indicator

Hexavalent chromium (CrVI) poses a serious risk to both human and environment health. Hence, a simple, robust, and efficient analytical method must be developed to monitor the presence of Cr(VI) in the environment. The current investigation concentrated on the colorimetric detection of Cr(VI) using TMB as indicator in the presence of H2O2. The study found that Cr(VI) reacts with H2O2 to generate hydroxyl radicals which oxidize TMB in a concentration dependent manner. Under optimized conditions, the method obtained a good linearity range (0.025–0.5 mg/L, r2 = 0.9944) with LOD and LOQ of 0.009 mg/L and 0.029 mg/L, respectively. The technique was further improved by the addition of EDTA in the sample preparation protocol to reduce the false positive result by the presence of ions like Cu2+, Fe3+, etc. The study recorded improved Cr(VI) recoveries (81.73–111.40 %) at different fortification levels (0.1–0.5 mg/L). Under optimized conditions, the EDTA added method obtained a good linear response (r2 = 0.9952) with a detection limit of 0.023 mg/L which is less than the prescribed limits by WHO (0.05 mg/L) and US EPA (0.1 mg/L) for drinking water. The developed analytical method is very simple without use of any nanomaterial and the results with natural water samples show that it has the potential for real-time detection of Cr(VI) in the environment.

Application of near-infrared spectroscopy as at line method for the evaluation of histamine in tuna fish (Thunnus albacares)

The assessment of histamine levels in fishery products has emerged as a paramount issue in the context of global food safety, given its profound implications for human health and the consequential impact on food quality and trade. Histamine intoxication, stemming from the ingestion of foods containing heightened histamine levels, results from the bacterial decarboxylation of histidine under conditions of improper handling, processing, or storage. This study endeavors to provide a thorough examination of histamine contamination in frozen-thawed tuna (Thunnus albacares) samples, employing an integrated approach that combines near-infrared spectroscopy (NIRS) with advanced machine learning techniques. One hundred and one samples were considered, and a systematic fortification process was applied to obtain samples with 4 histamine concentrations (0; 50; 150; 250 mg/kg); the fortification levels were confirmed by the LC-MS/MS analysis. Subsequently, NIRS spectra were collected and chemometric analyses, including modified partial least squares regression (MPLS) and support vector machine (SVM), were employed for quantitative and qualitative evaluation, respectively. Histamine quantification through MPLS utilizing the full spectrum exhibited good predictive performance in cross-validation and in hold-out validation (R2CV = 0.88; R2P = 0.74, respectively), confirming the potential of NIRS for estimating histamine levels in tuna. SVM classification models, both binary (presence/absence) and multiclass (four levels), demonstrated high accuracy (100% and 93%, respectively). The study highlights the effectiveness of NIRS combined with machine learning for rapid and accurate histamine detection in frozen-thawed tuna, offering a non-destructive, environmentally friendly alternative to traditional methods. This approach holds significant promise for food business operators and regulatory authorities, enhancing product safety, quality control, and decision-making processes related to histamine contamination in the seafood industry.

Bibliometric Analysis and a Call for Increased Rigor in Citing Scientific Literature: Folic Acid Fortification and Neural Tube Defect Risk as an Example.

The health benefits of vitamin B9 (folate) are well documented, particularly in regard to neural tube defects during pregnancy; however, much remains to be learned regarding the health effects and risks of consuming folic acid supplements and foods fortified with folic acid. In 2020, our laboratory conducted a population-based analysis of the Food Fortification Initiative (FFI) dataset to determine the strength of the evidence regarding the prevalence of neural tube defects (NTD) at the national level in response to mandatory fortification of cereal grains with folic acid. We found a very weak correlation between the prevalence of NTDs and the level of folic acid fortification irrespective of the cereal grain fortified (wheat, maize, or rice). We found a strong linear relationship between reduced NTDs and higher socioeconomic status (SES). Our paper incited a debate on the proper statistics to employ for population-level data. Subsequently, there has been a large number of erroneous citations to our original work. The objective here was to conduct a bibliometric analysis to quantitate the accuracy of citations to Murphy and Westmark's publication entitled, "Folic Acid Fortification and Neural Tube Defect Risk: Analysis of the Food Fortification Initiative Dataset". We found a 70% inaccuracy rate. These findings highlight the dire need for increased rigor in citing scientific literature, particularly in regard to biomedical research that directly impacts public health policy.

Determination of pentachlorophenol and its sodium salt residue in eggs using d-SPE method coupled with UPLC-MS/MS

ABSTRACT A method, improved d-SPE extration couple with ultra performance liquid chromatography tandem-mass spectrometry (UPLC-MS/MS), was developed for the determination of pentachlorophenol and its sodium salt residue in eggs. The sodium pentachlorophenol in the eggs was converted firstly into pentachlorophenol under acidic conditions, extracted by 1.5% (v/v) acetic acid/acetonitril, and the extraction solution was purified finally by disperse solid phase extraction. The composition of dispersive sorbents was optimized based on the recoveries and matrix effects. The recoveries at fortification levels of 0.5, 5 and 50.0 μg/kg in eggs ranged from 72.2% to 89.8% with the relative standard deviations of 0.2%~0.8%. The limits of quantification (LOQ) was 0.5 μg/kg. Market samples were quantified, and PCP residues were found, but all the detection levels were below the method LOQ. We demonstrated that UPLC – MS/MS in combination with modified d-SPE can be used to routinely monitor PCP residues in egg samples.

Study on the relevant parameters of direct economic loss assessment of reinforced concrete structure buildings considering seismic fortification and use function

The main cost and decoration cost of the building are the key parameters in the evaluation of the direct economic loss of the building. In the Earthquake Site Work Part 4 : Direct Loss Assessment of Disasters ( GB / T 18208.4-2011 ), considering factors such as economic development level, structural type, and building use, based on expert experience and engineering cost data, a grading index was developed and a corresponding correction coefficient was given to more accurately and reasonably assess the loss of the main building and the loss of decoration. In view of the rapid development of China 's economy and the acceleration of urbanization in the past ten years, the original grading indicators and coefficients need to be adjusted to adapt to the reality. This paper focuses on the reinforced concrete structure with various functions and wide distribution. By collecting a large number of corresponding building main body and decoration cost data, and combining with expert experience data, this paper analyzes the influence of seismic fortification level on the main body cost, as well as the influence of economic development level, decoration grade, use function and other factors on the decoration cost. The research results of this paper aim to provide reference for the update and refinement of several key parameters in the specification.

Determination and risk assessment of UV filters and benzotriazole UV stabilizers in wastewater from a wastewater treatment plant in Lüneburg, Germany

UV filters and benzotriazole UV stabilizers are considered emerging contaminants in the environment. LC–MS/MS and GC–MS methods, involving a single solid phase extraction protocol, were developed and validated to determine eight UV filters and seven UV stabilizers, respectively in wastewater from a wastewater treatment plant (WWTP) in Lüneburg, Germany. The LC–MS/MS method exhibited extraction recoveries of ≥ 71% at six different fortification levels with limits of detection (LODs) range of 0.02 ng mL−1 – 0.09 ng mL−1. Extraction recoveries of 47 to 119% at six different fortification levels were obtained for the GC–MS method with LODs range of 0.01 – 0.09 ng mL−1. Among the UV filters, the highest mean concentration was determined for octocrylene (OCR) in influent (3.49 ng mL−1) while the highest mean concentration was measured for 2-hydroxy-4-octyloxybenzophenone (UV 531) in influent (0.44 ng mL−1) among the UV stabilizers. Potential risk to aquatic organisms was assessed by the risk quotient approach. Only OCR presented a high risk to aquatic invertebrates whereas 2-ethylhexyl 4-methoxycinnamate (EHMC) and 2-ethylhexyl salicylate (EHS) posed high risks to algae. Benzotriazole UV stabilizers presented negligible risks to aquatic invertebrates and fish. This work reports the detection of rarely studied 4-aminobenzoic acid (PABA) and UV 531 in WWTP influent and effluent. The occurrence and risk assessment of target benzotriazole UV stabilizers in wastewater from a German WWTP was demonstrated for the first time.

The potential contributions of bouillon fortification to meeting micronutrient requirements among women and preschool children in Senegal: A modeling study using household consumption and expenditure survey data.

To reduce micronutrient deficiencies, Senegal mandates the fortification of refined oil with vitamin A and wheat flour with iron and folic acid. Expanding Senegal's large-scale food fortification programs to include fortified bouillon could help fill the remaining gaps in dietary micronutrient requirements. Using 7-day household food consumption data collected between 2018 and 2019, we assessed the potential contributions of bouillon fortified with vitamin A (40-250μg/g bouillon), folic acid (20-120μg/g), vitamin B12 (0.2-2μg/g), iron (0.6-5mg/g), and zinc (0.6-5mg/g) for meeting micronutrient requirements of women of reproductive age (WRA; 15-49 years old) and children (6-59 months old). Most households (90%) reported consuming bouillon, including poor and rural households. At modeled fortification levels, bouillon fortification reduced the national prevalence of inadequacy by up to ∼20 percentage points (pp) for vitamin A, 34 pp (WRA) and 20 pp (children) for folate, 20 pp for vitamin B12, 38 pp (WRA) and 30 pp (children) for zinc, and ∼8 pp for iron. Predicted reductions in inadequacy were generally larger among poor and rural populations, especially for vitamins A and B12. Our modeling suggests that bouillon fortification has the potential to substantially reduce dietary inadequacy of multiple micronutrients and could also help address inequities in dietary micronutrient inadequacies in Senegal.

Fortification of durum wheat fresh pasta with red chicory by-product powder: Effects on technological, nutritional, and sensory properties

The fortification of staple foods and the exploitation of agri-food by-products are the goals of modern food technologies. In this study, we prepared fortified pasta by replacing semolina flour with 5%, 10%, and 15% dried red chicory by-product powder (RCP), rich in fiber (27%) and healthy bioactive compounds (4.3%). The UHPLC-DAD-HRMS indicated hydroxycinnamic acids (HA), flavonoids (F), anthocyanins (A), and sesquiterpene lactones (SL) as the main bioactive compounds of RCP. The extraction recoveries of phenolic-fortified pasta (ranging from 0.2 to 13% for HAs to 5–28% for Fs and < 0.2% for As) suggest a high affinity with the semolina components, likely gluten or starch. The addition of RCP influenced (p < 0.05) the pasta's technological properties by inducing an increase in cooking loss, fully cooked time, and a decrease in the swelling index. The texture analysis showed that firmness and adhesiveness increased in the fortified sample. The sensory characterization showed a greater perception of vegetable and bitter flavor with increasing fortification levels. The RC15 sample had optimal technological, nutritional, and sensory characteristics. In conclusion, RCP could be an ingredient used to produce pasta with high fiber and bioactive compounds.

The Impact of Chlorella vulgaris Fortification on the Nutritional Composition and Quality Characteristics of Beef Burgers.

Chlorella vulgaris (C.V) is known for its high protein and nutrient contents and has been touted as a potential functional ingredient in food products. For this study, beef burgers were formulated with varying levels of Chlorella vulgaris fortification (0%, 0.5%, 1%, and 1.5% by weight). The nutritional composition, including proximate analysis and mineral content, was determined for each treatment group. The quality characteristics evaluated included thiobarbituric acid (TBA), total volatile base nitrogen (TVBN), pH, and total acidity. The study included extracting the active substances from Chlorella vulgaris using three solvents, 50% ethanol, 95% ethanol, and water, to evaluate the effect on the antimicrobial and antioxidant activity. The results showed that the water extract had the highest total phenolic content (183.5 mg gallic acid equivalent per gram) and the highest flavonoid content (54 mg quercetin per gram). The aqueous extract had the highest content of total antioxidants, followed by the 95% ethanol and 50% ethanol extracts. Meanwhile, the 50% ethanol extract showed the best antimicrobial activity, while the aqueous extract had less of an effect on Gram-positive bacteria and no effect on E. coli. For the burger treatments, at the end of the storage period, it was observed that the microbial load of the treatments decreased compared to the control, and there was a high stability in the total volatile base nitrogen (TVBN) values for the treatments compared to the control, reaching a value of 22.4 at month 5, which is well above the acceptable limit, indicating spoilage. The pH values were higher for all of the treatments, with a lower total acidity for all of the treatments compared to the control. In conclusion, utilizing Chlorella vulgaris algae as a natural preservative to extend the freshness of burgers is a sustainable and innovative approach to food preservation. By harnessing the power of this green superfood, we not only enhance the shelf life of our food products but also contribute to a healthier and more environmentally friendly food industry.

Consistent effect of Nile tilapia (Oreochromis niloticus) fortification in biscuit on nutritional composition, consumer perception and shelf life properties

Fish can be regarded as a promising protein ingredient for food fortification and enrichment. This study aimed to investigate the potential application of Nile tilapia fish as a dietary supplement. Fish powder was fortified in 0 (control), 5, 10 and 15% levels in dry ingredients by replacing wheat flour and other ingredients were kept constant. Then, biscuits were prepared and the proximate composition, physical and texture properties were determined, as well as sensory acceptance. The addition of fish had a statistically significant (p &lt; 0.05) effect on moisture, ash, fat, protein, carbohydrate, total energy, color, water activity, hardness and sensory acceptance. The protein content increased as much as 2.4-4.6 times as more fish was added. Results show that up to 5% fortification level, the biscuits were acceptable with improved functional properties compared to the control. There were significant changes in physical transformation in the biscuits packaged with polyethylene and aluminum foil at 25°C and 35°C, respectively. Fortification of fish powder could be used in the production of high-protein biscuits.

Development and validation of LC-MS/MS method for trace analysis of acrylamide, acrylic acid and N, N-methylene bis acrylamide in sandy loam soil

Acrylamide and N, N-methylene bis acrylamide are most commonly used monomer and crosslinker compounds employed in synthesis of super absorbent hydrogels. When applied as soil conditioners, there are apprehensions that these hydrogels degrade over time and thus may release the toxic monomers in the soil. A method was thus developed using Liquid Chromatography tandem mass spectrometry (LC-MS/MS) for the trace level quantification of acrylamide (AD), acrylic acid (AA) and N,N-methylene-bis-acrylamide (MBA) in sandy loam soil amended by two test hydrogels the Pusa Hydrogel and SPG 1118 hydrogel prepared using AD and MBA. The MRM (multiple reaction monitoring) transitions were optimized for both the compounds. Soil samples were extracted using dispersive solid-phase extraction (dSPE) with a modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) technique, employing acetonitrile. All analytes were quantified at trace levels within a five-minute run using UHPLC equipped with a C-18 column.Single laboratory validation of the developed method in soil matrix was conducted based on specificity, linearity, sensitivity, accuracy, precision, matrix effect and measurement of uncertainty. LC-MS/MS exhibited a linear response in the concentration range of 0.001 to 1 µg mL−1, with correlation coefficient >+0.99. Acceptable recovery (within 70–120 %) with repeatability (%RSD ≤20 %) was obtained at 0.01 to 1 µg g–1 fortification levels. LOQ (Limit of quantification) of the method for AD, AA and MBA in soil matrix were 0.05, 1 and 0.01 µg g–1, respectively. Both intra-laboratory repeatability and intermediate precision at LOQ suggested well acceptable precise (HorRat≈ 0.3) method for quantification. Matrix enhancement effect was observed in the order: AA>AD>MBA. The Expanded Uncertainty (EU) in soil matrix at LOQ was 21.64 %, 28 % and 19 % for AD, AA and MBA respectively. Groundnut and wheat grown with application of the hydrogels showed no detectable residues of monomers in soil samples (total n = 60) near the root zone at the time of crop harvesting.

Integration of ultrashort-chain compounds into the biomonitoring of per- and polyfluorinated substances in human plasma and serum

Ultrashort-chain (USC) per- and polyfluoroalkyl substances (PFAS) are small and very polar compounds with carbon chain lengths of shorter than C4. Their ubiquitous and high levels of occurrence in environmental aquatic systems have raised significant concern in conjunction with long-chain PFAS contamination. Measuring USC PFAS in blood can not only monitor human exposure but also serves as a valuable tool for studying the potential risks associated with USC PFAS exposure. The high polarity of USC PFAS poses a challenge to current analytical practices based on the reversed-phase liquid chromatography, primarily due to insufficient chromatographic retention. In this study, a simple and reliable workflow was developed for the simultaneous analysis of C1 to C10 perfluoroalkyl carboxylic and sulfonic acids, along with four alternative PFAS, in human plasma and serum. The chromatographic analysis was conducted using a polar-embedded reversed-phase LC column. Fetal bovine serum (FBS) was chosen for method validation due to its absence of all analytes, except for trifluoroacetic acid (TFA). Subsequently, a TFA isotope, 13C-TFA, was employed as a surrogate to assess the method accuracy for TFA in FBS. A single-step sample preparation procedure, conducted by mixing 100 µL of FBS with 200 µL of methanol, was demonstrated to be effective for the accurate and precise analysis of fortified FBS samples. Ten isotopes of C3 to C10 PFAS, serving as extracted internal standards, were added to the samples at 1 ppb to validate the accuracy of the entire workflow. Calibration standards were prepared in reverse osmosis water due to its cleanliness for all analytes. Phosphate-buffered saline was incorporated into the calibration standard solution to achieve similar chromatographic performance between standard and sample solutions. The calibration ranges varied among different analytes, spanning from 0.05 – 40 ppb, 0.1 – 40 ppb, 0.25 – 40 ppb, and 0.5 – 40 ppb. Method accuracy and precision were evaluated at three fortification levels, ranging from 0.4 to 30 ppb. All analytes and extracted internal standards exhibited recovery values within 20 % of the nominal concentration across all fortification levels. Satisfactory method precision was demonstrated with%RSD values <12 %. The validated method was applied to measure PFAS in NIST 1950 and 1957 standard reference human plasma and serum, affirming the established workflow is suitable for accurate quantification of C1 to C10 PFAS in human plasma and serum matrices.

Land Use Sustainability: Assessment of the Dynamic Response of Typical Bedrock-Buried-Hill Earth Fissure Sites in the Su-Xi-Chang Area

Disaster prevention and the mitigation of earth fissures is a key issue in the sustainable development of urban land. Structures directly avoiding earth fissures are not conducive to the rational planning and efficient utilization of urban construction. The Su-Xi-Chang area, which consists of the cities of Suzhou, Wuxi, and Changzhou, surrounded by Taihu Lake, has developed bedrock buried-hill earth fissures that are rare in the rest of the country. Existing research results have identified the genesis mechanisms, distribution patterns, and developmental characteristics of this type of fissure. Not only does the slow-variable activity of earth fissures cause direct damage to surface and underground structures, but in addition, when an earthquake occurs, the presence of earth fissures may cause the seismic response of the site to be altered or even strengthened, leading to unknown damage or the possible destruction of structures near the fissures. However, no studies have been conducted to assess the dynamic effects of bedrock-buried-hill earth fissure sites. Therefore, in this research, based on six typical bedrock-buried-hill-type earth fissures in the Su-Xi-Chang area, and in order to accurately reveal the dynamic amplification effect law of the earth fissure sites, systematic spectral analyses and comparisons of the microtremor signals were carried out by using the linear analysis method (Direct Fourier Transform Analysis) and the nonlinear analysis method (Hilbert–Huang Transform). The results show that bedrock-buried-hill-type earth fissures have a significant amplification effect on the dynamic response of the site; the amplification effect of bedrock-buried-hill fissure sites follows the same attenuation pattern, and the furthest range of the dynamic response on the site is about 25 m, beyond which the original seismic fortification level can be maintained; the extreme value of the amplification factor of the two sides of this type of site, as derived from the Fourier and HHT methods, is about double, and the nearest earth fissure region should be considered to have a raised seismic fortification intensity of more than double the original. The Hilbert–Huang transform method has good applicability for processing microtremor data, and nonlinear signal analysis methods can be considered comprehensive for future microtremor signal processing.