Spatial distribution, source, and fate of per- and polyfluoroalkyl substances in the surrounding environment of closed and converted fluorochemical factories in Fujian, China.

Following the closure of perfluorooctanesulfonic acid (PFOS) production to comply with the Stockholm Convention regulations or restrictions, manufacturers have shifted to developing short-chain alternatives like perfluorobutane sulfonic acid (PFBS). However, limited research has been conducted to evaluate the impact of this transition on the surrounding environment. This study focused on the spatial distribution, source, and fate of 18 per- and polyfluoroalkyl substances (PFAS) in the surrounding environment of the closure and transformation of two PFAS manufacturing plants in Fujian, China. The total concentrations of PFAS in surface water, sediment, and fish were within the range of 48.9-72,400 ng/L, 0.930-57.6 ng/g dw, and 3.33-1245 ng/g dw, respectively. The predominant compounds were PFBS, PFOS, and perfluorooctanoic acid (PFOA) among the three matrices. Principal component analysis highlighted significant differences in PFAS profiles across different regions of the Futun River, suggesting diverse sources of PFAS. Source apportionment indicated that despite being closed or converted for almost three years, the two factories still significantly impacted the surrounding environment. The shutdown factory mainly released PFAS characterized by perfluoroalkyl sulfonic acids. In contrast, the PFAS were released from conversion plant with the fingerprint being PFBS and perfluoroalkyl carboxylic acids. The conversion of the factories has resulted in the coexistence of long-chain and short-chain PFAS, which has complicated the composition of PFAS in the environment. As sewage treatment plant could not effectively remove PFBS and perfluorobutanoic acid (PFBA) in wastewater, and due to their strong migration ability, these chemicals had a wider impact range, increasing the difficulty of environmental restoration and management. Risk assessment showed that PFAS downstream of the two factories posed high or moderate ecological risks. Specifically, PFBS, PFOS, and PFOA displayed the highest risk quotients and should be paid further attention.

Trace the origin of yak meat in Xizang based on stable isotope combined with multivariate statistics.

In this study, the feasibility of tracing the origin of yak meat in Xizang Autonomous Region based on stable isotope combined with multivariable statistics was researched. The δ13C, δ15N, δ2H and δ18O in yak meat were determined by stable isotope ratio mass spectrometry, and the data were analyzed by analysis of variance, fisher discriminant analysis (FDA), back propagation (BP) neural network and orthogonal partial least squares discrimination analysis (OPLS-DA). The results showed that the δ13C, δ15N, δ2H and δ18O had significant differences among different origins (P < 0.05). The overall original correct discrimination rate of fisher discriminant analysis was 89.7 %, and the correct discrimination rate of cross validation was 88.2 %. The correct classification rate of BP neural network based on training set was 93.38 %, and the correct classification rate of BP neural network based on test set was 89.83 %. The OPLS-DA model interpretation rate parameter R2Y was 0.67, the model prediction rate parameter Q2 was 0.409, which could distinguish yak meat from seven different producing areas in Xizang Autonomous Region. The results showed that the origin of yak meat in Xizang Autonomous Region can be traced based on stable isotope combined with multivariate statistics.

Rapid analysis technologies with chemometrics for food authenticity field: A review.

In recent years, the problem of food adulteration has become increasingly rampant, seriously hindering the development of food production, consumption, and management. The common analytical methods used to determine food authenticity present challenges, such as complicated analysis processes and time-consuming procedures, necessitating the development of rapid, efficient analysis technology for food authentication. Spectroscopic techniques, ambient ionization mass spectrometry (AIMS), electronic sensors, and DNA-based technology have gradually been applied for food authentication due to advantages such as rapid analysis and simple operation. This paper summarizes the current research on rapid food authenticity analysis technology from three perspectives, including breeds or species determination, quality fraud detection, and geographical origin identification, and introduces chemometrics method adapted to rapid analysis techniques. It aims to promote the development of rapid analysis technology in the food authenticity field.

Rapid authenticity assessment of PGI Hongyuan yak milk based on SICRIT-QTOF MS.

Hongyuan (HY) yaks live in a pollution-free environment, making HY yak milk a green food, but their short milk production period and low milk yield make yak milk precious and expensive. The phenomenon of counterfeiting HY yak milk with ordinary milk from other origins has already occurred, so the authenticity assessment of HY yak milk is necessary. This study developed a rapid soft ionisation by chemical reaction in transfer quadrupole time-of-flight mass spectrometry (SICRIT-QTOF MS) for HY yak milk differences assessment. Principal component analysis and orthogonal least squares discriminant analysis showed differences between HY milk and the other three origins. Twenty-eight differential compounds were screened out by variable importance in projection, fold change, P-value, and database matching. Furthermore, six characteristic compounds (proline, 2-hydroxy-3-methylbutyric acid, and l-isoleucine, etc.) of HY samples were putatively identified. The study demonstrated that SICRIT-QTOF MS has great potential for rapidly distinguishing the milk origin.

A New and Effective Method to Trace Tibetan Chicken by Amino Acid Profiling.

As a "rare bird on the plateau", the Tibetan chicken is rich in nutrition and has high medicinal value. In order to quickly and effectively identify the source of food safety problems and to label fraud regarding this animal, it is necessary to identify the geographical traceability of the Tibetan chicken. In this study, Tibetan chicken samples from four different cities in Tibet, China were analyzed. The amino acid profiles of Tibetan chicken samples were characterized and further subjected to chemometric analyses, including orthogonal least squares discriminant analysis, hierarchical cluster analysis, and linear discriminant analysis. The original discrimination rate was 94.4%, and the cross-validation rate was 93.3%. Moreover, the correlation between amino acid concentrations and altitudes in Tibetan chicken was studied. With the increase in altitude, all amino acid contents showed a normal distribution. For the first time, amino acid profiling has been comprehensively applied to trace the origin of plateau animal food with satisfactory accuracy.

Effects of Fertilizer on the Quality and Traceability of Tibet highland Barley (Hordeum vulgare L.): A Diagnosis Using Nutrients and Mineral Elements.

Production areas influence the quality of highland barley (Hordeum vulgare L.), and fertilization levels may be associated with the origin traceability of highland barley. As the main object of the study, a collection of highland barley was planted in different areas in Tibet, China, to explore the effect of fertilizer on the quality and traceability of highland barley. We carried out field experiments with and without fertilizer treatment (using urea and diamine phosphate). Highland barley was distinguished by nutrient and mineral element contents in combination with chemometric methods. The results indicated that fertilizer treatment significantly affected some mineral element contents in highland barley and improved the accuracy of highland barley traceability. The combination of nutrients and mineral elements could distinguish highland barley from those raised in other areas due to influence of growing environment. P, K, Fe, and Cu provided a great contribution to the classification of highland barley. Thus, the combination of nutrients and mineral elements can be used as a powerful tool to track highland barley, indicating that fertilization treatment should be considered when tracing highland barley.

Direct analysis in real time high-resolution mass spectrometry for authenticity assessment of lamb.

In comparison to more traditional methods of determining food authenticity, such as gas chromatography analysis, the primary advantages of DART-HRMS include its high speed and throughput of analysis. This study used a non-targeted metabolomics method based on real-time high-resolution mass spectrometry combined with chemometric analysis to distinguish lamb samples from four regions. Orthogonal least squares-discriminant analysis revealed a distinct difference between these four lamb regions. The potential markers were chosen based on the variable's importance in projection values, variance, and fold change. A total of 79 markers were identified using the matching chemistry database. These markers differed significantly between lambs in four regions according to heatmap analysis. The linear discriminatory analysis model had an initial classification rate of 100.0% and a cross-validation accuracy of 82.50% on the identified markers. The research demonstrates that DART-HRMS can perform a rapid authentication evaluation of lamb samples.

Study of the occurrence of toxic alkaloids in forage grass by liquid chromatography tandem mass spectrometry.

The toxic alkaloids in forage grass present a serious health hazard to humans and livestock, especially ergot alkaloids (EAs), pyrrolizidine alkaloids (PAs) and tropane alkaloids (TAs). Hence, there is a need for a simultaneous method that allows these dangerous plant toxins to be determined. A simple and effective method was developed to determine fifteen toxic alkaloids (EAs, PAs and TAs) in forage grass using the QuEChERS method and liquid chromatography tandem mass spectrometry (LC-MS/MS). The developed method was validated with average recoveries ranging from 63.10 to 102.10%, and relative standard deviations lower than or equal to 6.39% were obtained. Good linearity over the concentration range of 10-600 µg/kg dry matter (DM) was observed for the target alkaloids. The determination coefficients R2 calculated for each of the matrix calibration curves were greater than 0.99. The limits of detection and quantification were 5 µg/kg DM and 10 µg/kg DM, respectively. The reproducibility of the method was verified in three laboratories: all of the mean recoveries of 15 alkaloids were higher than 60%, and the relative standard deviations in alkaloids between laboratories were all less than 14.24%. The proposed method was applied to analyse 134 forage grass samples from the meadow steppe of Inner Mongolia to monitor toxic alkaloids. A significant difference in the frequency of contamination was found between different herbage species and different regions.

Discrimination of mutton from different sources (regions, feeding patterns and species) by mineral elements in Inner Mongolia, China.

The traceability of mineral element fingerprints to mutton in a small area of China was studied. The element data of 104 sheep and 24 goat samples from Inner Mongolia were measured, and the data were analyzed by multivariate statistical analysis from different origins, species and feeding patterns. The results shows that 11 elements (Mg, Al, K, Ca, Mn, Fe, Cu, Zn, Rb, Sr, Ba) in sheep meat had significant differences between different regions (P < 0.05), and the results of linear discriminant analysis (LDA) showed that the accuracy of the original classification rate was 95.2%, and the cross-validation rate was 85.9%. Goat meat and sheep meat samples from Alxa League were also clearly identified with LDA results showing that the cross-validation accuracy of the two species was 70.2%. Then the feeding patterns of sheep meat were effectively classified. The results showed that the multi-element analysis has certain potential as a method to distinguish mutton in a small area.

Study on the origin traceability of Tibet highland barley (Hordeum vulgare L.) based on its nutrients and mineral elements.

The potential of traceability by nutrients and mineral elements in highland barley (Hordeum vulgare L.) from five cities in Tibet were investigated. The results showed that there were significant differences in nutrients and mineral elements in highland barley from different regions (P < 0.05). The original classification accuracy of linear discriminant analysis (LDA) was 78.3%, and the discrimination accuracy of training set samples based on partial least-squares discriminant analysis (PLS-DA) model was over 65%. The results of correlation analysis show that five elements (Fe, Zn, K, Mn and P) in highland barley are related to the concentration of elements in soil, while three elements (Ca, Cu and Mg) in highland barley have no obvious correlation with soil, because the special natural environment in Tibet affecting the growth of highland barley. This indicates that the origin traceability of highland barley can be achieved by measuring its nutrients and mineral elements.

Authentication of organic pork and identification of geographical origins of pork in four regions of China by combined analysis of stable isotopes and multi-elements.

The purpose of this study was to verify that the organic status of pork purchased in the markets from four different regions of China can be authenticated by the combined analysis of stable isotopes and multiple elements. Four stable isotope ratios (δ13C, δ15N, δ2H and δ18O) and the concentrations of seven elements (K, Na, Mg, Ca, Fe, Cu and Se) were determined in organic and conventional pork samples from four locations of China. Principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) were used to analyze stable isotope ratios and multi-element concentrations in pork. Based on the limited database of analytical values, the methodology would be potentially able to confirm whether a sample of pork came from the region and organic status it claimed. These results provide a possibility for authenticity of organic agricultural products from a large scope such as a province even a country.

Rapid simultaneous determination of 160 drugs in urine and blood of livestock and poultry by ultra-high-performance liquid chromatography-tandem mass spectrometry.

In order to address the specific question of food safety in livestock and poultry, it is imperative to monitor veterinary drugs at every moment in the process of livestock and poultry breeding. Thus, multi-residue analysis of a wide variety of drugs using ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) has become a tool of critical significance, especially for veterinary drug monitoring programs. A total of 160 compounds, belonging to 17 different families of veterinary drugs, were investigated in the urine and blood of livestock and poultry. Drug samples were extracted using a slightly acidic acetonitrile solution. The QuEChERS (quick, easy, cheap, effective, rugged, and safe) preparation method, combined with dispersive solid phase extraction (d-SPE) was compared with the approach of solid phase extraction (SPE). In the end, the QuEChERS extraction procedure was selected to reduce matrix effects and efficiently extract target veterinary drugs, and d-SPE was applied as a cleanup step. Electrospray ionization coupled with positive dynamic multiple reaction monitoring (dMRM) was utilized for the analysis of 160 different drugs in a single chromatographic run of 24 min. The efficiency of this method was evaluated using 7 matrices (pig blood, cattle blood, sheep blood, chicken blood, pig urine, cattle urine, and sheep urine). Good linearity was obtained for the analytes in a concentration range of 1-100 ng/mL, with correlation coefficients higher than 0.990. Most of the 160 drugs studied gave estimated limits of detection (LOQs) of 1 ng/mL, with some LOQs reaching as much as 5 ng/mL. The mean recoveries at four spike-in levels of 1, 5, 10, and 50 ng/mL, ranged from 60% to 120%. The intra-day precision measurements had coefficients of variation (n = 6) <15%, and the inter-day precision measurements were below 25%. Our method was applied in real samples and proved to be adequate for routine analysis. The proposed method proved to be simple, rapid and reliable for monitoring 160 drugs in the urine and blood of livestock and poultry, and can also be used for food safety monitoring.