Concentration and health risk assessment of 16 rare earth elements in six types of tea in China.

Rare Earth Elements (REEs) have been implicated in potential health effects. However, the health risk of REE exposure among tea drinkers in China remains poorly understood. This study aimed to characterize the concentration of REEs in different tea categories and evaluate the associated health risks for tea consumers in China. By analyzing the content of 16 REEs in 4326 tea samples from China, the exposure level of REEs to the general population was estimated. The content of these 16 REEs was similar across six types of tea, with oolong tea exhibiting the highest levels. The concentration of light rare earth elements (LREEs) in six types of tea was higher than that of heavy rare earth elements (HREEs). The daily mean and 95th percentile (P95) exposure to REEs from tea for the general population in China were 0.0328 µg/kg BW and 0.1283 µg/kg BW, respectively, which are significantly lower than the temporary acceptable daily dose (tADI). Our findings suggest that REEs from tea do not pose a known health risk to Chinese consumers.

Macrophage polarization as a novel endpoint for assessing combined risk of phthalate esters.

Combined exposure to phthalate esters (PAEs) has garnered increasing attention due to potential synergistic effects on human health. This study aimed to develop an in vitro model using human macrophages to evaluate the combined toxicity of PAEs and explore the underlying mechanisms. A high-throughput screening system was engineered by expressing a PPRE-eGFP reporter in THP-1 monocytes to monitor macrophage polarization upon PAEs exposure. Individual PAEs exhibited varied inhibitory effects on M2 macrophage polarization, with mono(2-ethylhexyl) phthalate (MEHP) being the most potent. Isobologram analysis revealed additive interactions when MEHP was combined with other PAEs, resulting in more pronounced suppression of M2 markers compared to individual compounds. Mechanistic studies suggested PAEs may exert effects by modulating PPARγ activity to inhibit M2 polarization. Notably, an equimolar mixture of six PAEs showed additive inhibition of M2 markers. In vivo experiments corroborated the combined hepatotoxic effects, with mice exposed to a PAEs mixture exhibiting reduced liver weight, dyslipidemia, and decreased hepatic M2 macrophages compared to DEHP alone. Transcriptome analysis highlighted disruptions in PPAR signaling, and distinct pathway alterations on cholesterol metabolism in the mixture group. Collectively, these findings underscore the importance of evaluating mixture effects and provide a novel approach for hazard assessment of combined PAEs exposure with implications for environmental health risk assessment.

Identification of Active Components for Sports Supplements: Machine Learning-Driven Classification and Cell-Based Validation.

The identification of active components is critical for the development of sports supplements. However, high-throughput screening of active components remains a challenge. This study sought to construct prediction models to screen active components from herbal medicines via machine learning and validate the screening by using cell-based assays. The six constructed models had an accuracy of >0.88. Twelve randomly selected active components from the screening were tested for their active potency on C2C12 cells, and 11 components induced a significant increase in myotube diameters and protein synthesis. The effect and mechanism of luteolin among the 11 active components as potential sports supplements were then investigated by using immunofluorescence staining and high-content imaging analysis. It showed that luteolin increased the skeletal muscle performance via the activation of PGC-1α and MAPK signaling pathways. Thus, high-throughput prediction models can be effectively used to screen active components as sports supplements.

Advancing food safety risk assessment in China: development of new approach methodologies (NAMs).

Novel techniques and methodologies are being developed to advance food safety risk assessment into the next-generation. Considering the shortcomings of traditional animal testing, new approach methodologies (NAMs) will be the main tools for the next-generation risk assessment (NGRA), using non-animal methodologies such as in vitro and in silico approaches. The United States Environmental Protection Agency and the European Food Safety Authority have established work plans to encourage the development and application of NAMs in NGRA. Currently, NAMs are more commonly used in research than in regulatory risk assessment. China is also developing NAMs for NGRA but without a comprehensive review of the current work. This review summarizes major NAM-related research articles from China and highlights the China National Center for Food Safety Risk Assessment (CFSA) as the primary institution leading the implementation of NAMs in NGRA in China. The projects of CFSA on NAMs such as the Food Toxicology Program and the strategies for implementing NAMs in NGRA are outlined. Key issues and recommendations, such as discipline development and team building, are also presented to promote NAMs development in China and worldwide.

The occurrence and probabilistic risk assessment of 3-MCPDEs and GEs in infant formulas from Chinese market employing Monte Carlo simulation technique.

3-monochloropropane-1,2-diol esters (3-MCPDEs) and glycidyl esters (GEs) are food contaminants and have arisen continuous attention due to their toxicity, especially towards infants. Current risk assessment of these contaminants was mostly employing deterministic approaches, lacking quantitative characterization of the likelihood, incidence, or severity of the risks involved. Herein, 3-MCPDE and GE levels in 46 representative infant formulas (IFs) from Chinese market were determined by GC-MS/MS. Then, combining the occurrence data and consumption data from China National Food Consumption Survey, the Monte Carlo simulation-based probabilistic model for risk assessment of 3-MCPDEs and GEs in IFs from Chinese market was established. The results showed that all P90 (90th percentiles) hazard quotient values were below 1, demonstrating 3-MCPDEs didn't pose health risks to most populations aged 0-36 months old. However, for 0-12 months old groups, P10 (10th percentiles) margin of exposure values were all below 25000, indicating GEs may pose potential risks to 10% of this group. Uncertainty analysis revealed that the probabilistic model had considered uncertainties of model input and distribution, and realized refined assessment. This study is the first report on probabilistic assessment of 3-MCPDEs and GEs in IFs, which also provided references for the formulation of related regulatory limits in China.

Impact of food matrices on the characteristics and cellular toxicities of ingested nanoplastics in a simulated digestive tract.

Microplastic and nanoplastic (MNP) pollution has become a major global food safety concern. MNPs can interact with food matrices, and their passage through the gastrointestinal tract can modify their properties. To explore whether and how food matrices influence MNP toxicity, we investigated the interactions between polystyrene nanoplastics (PS-NPs) and food matrices, using an in vitro gastrointestinal digestion model. Then, we tested cell viability, particle uptake and cellular toxicities induced by PS-NPs with food matrices in Caco-2 cells. The results showed that PS-NPs were aggregated, both with and without food matrices, after in vitro gastrointestinal digestion. Glyceryl trioleate exerted greater ability to stabilize digestas and to disperse PS-NPs than starch and bovine serum albumin. The protein corona's protein composition on PS-NPs varied when it interacted with different food matrices. Moreover, when combined with food matrices, the PS-NPs' uptake was enhanced, thus aggravating cellular inflammation, stress, and apoptosis levels. Finally, through co-exposure to a mixture of food matrices, we found a combined negative effect of PS-NPs and cadmium on cellular inflammation, stress, and apoptosis levels. This is the first study to compare the impact of various food matrices on the characteristics and cellular toxicities of ingested NPs in a simulated digestive tract.

Monosodium Glutamate Intake and Risk Assessment in China Nationwide, and a Comparative Analysis Worldwide.

The sixth Total Diet Study (TDS) of China included a countrywide study to assess the health effects of MSG (monosodium glutamate). MSG detection, consumption analysis, and risk assessment were conducted on 168 samples from seven food categories of the most typical Chinese daily diet. The highest value of MSG in the daily diet of the Chinese population was 8.63 g/kg. An MSG intake of 17.63 mg/kg bw/d for the general population of China was obtained from content measurements combined with food consumption, while the data from the apparent consumption survey alone gave 40.20 mg/kg bw/d. The apparent consumption did not consider the loss of MSG during food cooking, resulting in an overestimate. To offer a global perspective, MSG content, food category contributions, and ingestion levels across nations were summarized and thoroughly investigated. A realistic, logical, and precise risk assessment protocol for MSG daily intake was developed in this article.

Dietary Exposure to Glutamates of 2- to 5-Year-Old Toddlers in China Using the Duplicate Diet Method.

A duplicate diet collection method was used to estimate dietary exposure to glutamates in children aged 2-5 years in selected provinces of China. Daily duplicate diet samples were collected from 86 healthy toddlers over three consecutive days. Glutamates were analyzed using ultra-high-pressure liquid chromatography-MS/MS (UHPLC-MS/MS). Results showed that the highest glutamates content was found in mixed meals, at 5.12 mg/kg, followed by powdered formula (3.89 mg/kg), and milk and dairy products (2.29 mg/kg). The total mean daily dietary exposure for subjects was 0.20 mg/kg BW, and P95 daily dietary exposure was 0.44 mg/kg BW, both below the acceptable daily intake (ADI) (120 mg/kg BW) recommended by the Joint (FAO/WHO) Expert Committee on Food Additives (JECFA) and the ADI (30 mg/kg BW) set by the European Food Safety Authority (EFSA). Hence it can be considered that glutamates exposure would cause low risk in this group.

Risk assessment of eighteen elements leaching from ceramic tableware in China.

Ceramic products are among the most frequently used food contact materials. Health risks associated with ceramic tableware usually arise from the migration of heavy metals. In this study, 767 pieces of ceramic tableware of different shapes and types were collected across China, and the migration levels of 18 elements were determined using inductively coupled plasma mass spectrometry. Migration tests were conducted according to the Chinese National Food Safety Standard - Ceramic Ware (GB 4806.4) with microwaveable and non-microwavable samples under different conditions. The food consumption of consumers via different shapes of ceramic tableware was obtained through a self-reported web-based survey, and the estimated dietary intakes of the studied elements were calculated accordingly. The exposure assessment showed that certain metals leached from the ceramic tableware at levels of concern. In addition, the applicability of the migration experiment conditions for microwaveable ceramic ware in GB 4806.4 needs to be further investigated.

Investigation of Microplastics (≥10 µm) in Meconium by Fourier Transform Infrared Microspectroscopy.

Microplastics are prevalent emerging pollutants with widespread distribution in air, land and water. They have been detected in human stool, blood, lungs, and placentas. However, human fetal microplastic exposure remains largely under-studied. To assess fetal microplastic exposure, we investigated microplastics using 16 meconium samples. We used hydrogen peroxide (H2O2), nitric acid (HNO3) and a combination of Fenton's reagent and HNO3 pretreatment methods respectively to digest the meconium sample. We analyzed 16 pretreated meconium samples with an ultra-depth three-dimensional microscope and Fourier transform infrared microspectroscopy. The result showed that H2O2, HNO3 and Fenton's reagent combined with HNO3 pretreatment methods could not digest our meconium samples completely. Alternatively, we developed a novel approach with high digestion efficiency using petroleum ether and alcohol (4:1, v/v), HNO3 and H2O2. This pretreatment method had good recovery and non-destructive advantages. We found no microplastics (≥10 µm) in our meconium samples, indicating that microplastic pollution levels in the fetal living environment are miniscule. Different results between previous studies' and ours underscore that comprehensive and strict quality control are necessary for further studies on microplastic exposure using human bio-samples.

Trends of caffeine intake from food and beverage among Chinese adults: 2004-2018.

Caffeine is a kind of psychostimulant that naturally exist in foods. The benefits and risks of caffeine depend on the dose. Moreover, the intake of caffeine from dietary sources in China has seldom been assessed. We calculated the dietary caffeine intake of Chinese adult consumers from 2004 to 2018 and analyzed its consumption trends by using data from the China Health and Nutrition Survey and the National Food and Beverage Consumption Survey. Caffeine contents in different dietary items were determined by HPLC. Monte Carlo simulations were applied to estimate caffeine intake. Mann-Kendall trend test and linear regression were used to analyze the trend of caffeine consumption. Among 79,173 individuals, 3972 (5%) of the adult Chinese population consumed caffeine between 2004 and 2018. The average caffeine intake was 123 mg/day for male consumers and 116 mg/day for female consumers. The median and P75 caffeine intake raised over the 14 years. Traditional tea leaves, coffee and sodas are the main sources of caffeine intake. Our findings indicate that most Chinese adults consumed caffeine within the safe level (400 mg/day), but the caffeine consumption has shown an increasing trend in recent 14 years.

Study of the evolution of 3-MCPDEs and GEs in the infant formula production chain employing a modified indirect method based on magnetic solid phase extraction.

Herein, a modified indirect method was established for the determination of 3-monochloropropane-1,2-diol esters (3-MCPDEs) and glycidyl esters (GEs), employing magnetic solid phase extraction by boronic acid-functionalized magnetic nanoparticles to replace the traditional clean-up procedure. Compared with routine methods, it has been proved to be more sensitive with limits of detection in the range of 0.02-1.5 µg/kg and less susceptible to contamination of phenylboronic acid derivatives and fatty acid methyl esters. The proposed method was applied to analyze 42 samples covering the entire infant formula (IF) production chain. Results revealed that homogenization process contributed 79-91 % of the total growth of the contaminants due to the vegetable oil addition, while the following evaporation and spray-drying processes contributed 9-21 % of the total growth owing to involved heat treatment. The GE levels in final IF products exceeded the maximum level set by EU regulation 2020/1322, indicating quality safety concerns in the production chain.

Dietary Exposure Assessment of Rare Earth Elements in the Chinese Population.

Rare earth elements (REEs) are widely found in foods. A high intake of REEs may have associations with adverse effects on human health. This study aimed to investigate the concentrations of REEs in foods in China and to assess the risk of dietary REEs exposure in the Chinese population. The mean concentrations of the total REEs in 27,457 food samples from 11 food categories ranged from 0.04 to 1.41 mg/kg. The daily mean dietary exposure of the total REEs was 1.62 µg/kg BW in the general Chinese population and ranged from 1.61 to 2.80 µg/kg BW in different sex-age groups. The high consumer exposure (95th percentile, P95) was 4.83 µg/kg BW, 9.38% of the temporary ADI (tADI) of REEs (51.5 µg/kg BW). None of the P95 exposure exceeded the tADI in all of the sub-groups. Lanthanum, cerium, and yttrium accounted for approximately 63% of the total exposure of the 16 REEs. The hazard index of 16 REEs was far below 1. Therefore, the health risk of dietary REEs exposure in the general Chinese population was low. No cumulative risk was found for the 16 REEs in China. The results indicate there was no need to stipulate the limits of REEs in foods.

Brain single-nucleus transcriptomics highlights that polystyrene nanoplastics potentially induce Parkinson's disease-like neurodegeneration by causing energy metabolism disorders in mice.

With the prevalence of nanoplastics in daily life, human exposure is inevitable. However, whether and how nanoplastics cause neurotoxicity in humans remains obscure. Herein, we conducted a 28-day repeated dose oral toxicity study in C57BL/6 J mice exposed to 0.25-250 mg/kg body weight (BW) polystyrene nanoplastics (PS-NPs, 50 nm). We revealed that PS-NP-caused Parkinson's disease (PD)-like neurodegeneration in mice by multiple approaches. Furthermore, a single-nucleus RNA sequencing of 62,843 brain nuclei unearthed PS-NP-induced cell-specific responses in the mouse brains. These disturbed responses among various brain cells were primarily linked with energy metabolism disorder and mitochondrial dysfunction in all brain cells, and especially in excitatory neurons, accompanied by inflammatory turbulence in astrocytes and microglia, dysfunction of proteostasis and synaptic-function regulation in astrocytes, oligodendrocytes, and endotheliocytes. These responses may synergize in PS-NP-motivated PD-like neurodegeneration pathogenesis. Moreover, we verified these single-nucleus transcriptomics findings on different brain regions and found that PS-NPs potentially caused PD-like neurodegeneration primarily by causing energy metabolism disorder in the substantia nigra pars compacta (SNc) and striatum. This manifested as decreases in adenosine triphosphate (ATP) content and expression levels of ATP-associated genes and proteins. Given nanoplastics' inevitable and growing exposure risks to humans, the neurological health risks of nanoplastic exposure warrant serious consideration.

Quantitative probabilistic assessment of caffeine intake from tea in Chinese adult consumers based on nationwide caffeine content determination and tea consumption survey.

Caffeine has known effects on the central nervous and cardiovascular systems. An intake up to 400 mg/day does not give rise to health concerns. Tea, a major source of caffeine, is highly consumed in China. However, the potential health risk of caffeine from tea has not been well evaluated. The present study assessed caffeine intake levels from tea for Chinese adult consumers. We collected 1,398 samples of green, black, dark, jasmine, oolong, white, and yellow tea from 17 provinces. The caffeine content was determined by HPLC. The average contents were 27 (oolong tea) - 43 (yellow tea) mg/g. The leaching rate of caffeine into the water was about 100%. Tea consumption data were from the National Beverage Consumption Survey 2013-2014. Monte Carlo simulations were applied to estimate the distribution of caffeine intake. The average caffeine intake from tea was 180 mg/day of all consumers. Green, dark, and black tea were the primary sources. Males (197 mg/day) consumed more caffeine than females (136 mg/day) on average, but females older than 71 years had the highest intake level (259 mg/day) among all subgroups. Over 90% of Chinese adult tea drinkers have caffeine intake under 400 mg/day.

Application of the maximum cumulative ratio (MCR) as a screening tool for the evaluation of multiple metal mixtures in shellfish in Chinese population.

The objective of this study was to investigate the potential effects from exposure to multiple metals, including cadmium (Cd), chromium (Cr), arsenic (As), mercury (Hg), nickel (Ni) and lead (Pb) that exist in shellfish in Chinese populations, and evaluate the impacts of cumulative exposures among individuals. A total 15,469 individual shellfish samples were analyzed following a protocol for elemental analysis. A total of 25,669 respondents were selected through stratified multi-stage cluster sampling from  31 survey sites in China. Individual shellfish consumption data and body weight were collected and analyzed with a 24-hour dietary recall method on three non-consecutive days. The consumers were divided into two groups: aged 2-12 years group and aged ≥13 years. Exposure levels were estimated based using a semi-probabilistic risk assessment method and cumulative exposures among individual persons using the maximum cumulative ratio (MCR) method. The mean, median and 95th percentile of all metals exposure for age 2-12 years group were higher than age ≥13 years group, but none exceeded the respective reference doses of the metals. The mean hazard indices (HI) of each metal in shellfish for both age groups were less than 1. The MCR values calculated among 1283 consumers ranged from 1.28 to 3.25 with the average MCR value was 2.22. There were 51 (3.98%) consumers in group I, 1186 (92.44%) consumers in group II, 26(2.03%) consumers in group III A, and 20 (1.56%) consumers in group III B. And cadmium (Cd) and lead (Pb) produced the HQMax that trigged cumulative exposures. It was concluded that heavy metals did not present a potential health risk to people solely through shellfish. The cumulative risks indicated that 7.56% of the surveyed consumers were of concern because of high HI of metals exposure, and Cd, Pb, and Ni made significant contributions to the potential risk.

Risk assessment of rare earth elements in fruits and vegetables from mining areas in China.

Assessment of contaminated food through the dietary intake is essential for human health. To investigate the health risk of rare earth element (REE) exposure to fruits and vegetables in mining areas in China, we collected 288 fruit samples and 942 vegetable samples from four representative mining points (Bayan Obo in Inner Mongolia, Weishan in Shandong, Maoming in Guangdong, Longnan in Jiangxi) and their control areas. The content of REEs was determined by inductively coupled plasma-mass spectrometry (ICP-MS). The total REEs in fruits from mining and control areas were 12.90 µg kg-1 and 11.89 µg kg-1, and in vegetables were 92.90 µg kg-1 and 62.38 µg kg-1, and the difference was statistically significant in vegetables (P = 0.048). The drupes had more REE concentration in fruits (68.41 µg kg-1, 16.90 µg kg-1 in mining and control areas, respectively) (P < 0.01), and the leafy vegetables had more REE concentration in vegetables (245.81 µg kg-1, 123.51 µg kg-1 in mining and control areas, respectively) (P < 0.01). With the enrichment of light rare earth elements (LREE), the REE distribution patterns coincided in mining and control areas and different types of fruits and vegetables. The health risk assessment indicated that the estimated daily intakes (0.02-0.06 µg kg-1 day-1, 0.53-1.22 µg kg-1 day-1 for fruits and vegetables, respectively) were lower than the allowable daily intake value (60.4 µg kg-1 day-1). In mining areas, REEs obtained from fruits and vegetables were insufficient to cause health damage to human beings. However, sustained exposure to low REEs, especially for children, still needs attention.

Investigation of factors influencing the release of chloropropanols (3-MCPD and 1,3-DCP) from food contact paper.

Chloropropanols such as 3-monochloropropane-1,2-diol (3-MCPD) and 1,3-dichloro-2-propanol (1,3-DCP) have drawn increasing attention due to their release from food contact paper and their potential carcinogenic effects. In this study, the effects were investigated of water extraction conditions on release of chloropropanols from food contact paper, and the extraction efficiencies of chloropropanols by water extract and migration method were compared. Cold water was found to be more severe than hot water for extraction of chloropropanols, with the highest water extraction value obtained at 23°C. Two hours of extraction was sufficient as the chloropropanols can be fully extracted from food contact paper within a short period of time. Increase of temperature in the range of 10°C-60°C had little impact on release of chloropropanols, however, the extraction of chloropropanols decreased when high temperatures (80°C or above) were applied due to volatilisation losses. Hence, attention should be paid when choosing extract conditions representing the worst-case scenario. The water extraction value using EN 645 method gives higher results compared to migration test described in GB 31604.1 and GB 5009.156, suggesting that the water extract method was probably more severe. For migration test, aqueous-based simulants were found to be more conservative than oil-based simulants, suggesting the conventional experiment conditions applicable for compliance test of chloropropanols migration can be simplified and optimised.

Survey of six metal contaminants and impurities and eleven metals and alloy components released from stainless-steel sheets on the Chinese market.

The release of metal elements from stainless-steel products in contact with food may endanger human health. To protect human health, different countries or international organisations have formulated corresponding regulations or technical guidelines. Limits for only five metal elements are stipulated in the China National Food Safety Standard (GB 4806.9) and food simulants and test conditions are fixed regardless of the actual use condition. In this study, inductively coupled plasma mass spectroscopy and inductively coupled plasma optical emission spectroscopy were used to measure the concentrations of six metal contaminants and impurities and 11 metals and alloy component released from stainless-steel sheets on Chinese market. The effects were also investigated on metal release of six grades (201, 202, 304, 430, 443, and 30Cr13) and 6 exposure conditions (food simulant 5 g L-1 citric acid or 4 vol% acetic acid, contact temperature 70 °C or 100 °C, and contact time 2 h, 0.5 h, or 0.5 h followed by ambient temperature for 24 h). For reusable stainless-steel sheets, especially for grade 30Cr13, it was essential to perform three consecutive release tests to check compliance. However, there was no need to conduct three consecutive release tests for the other five grades if the results of the first test met the regulations. It was recommended that 5 g L-1 citric acid should be used as food simulant and contact temperature and time should be based on the actual using conditions. No relationships were found between metal release amounts and contact test temperature or time. The specific release limits for Pb, Cr, As, Cd, and Ni should be lowered and Al, Mn, and Fe be added in GB 4806.9. The results of this study can be a reference for further analysis of the release behaviour of metal elements in actual stainless-steel products.

Occurrence of 3- and 2-monochloropropanediol esters in infant formulas in China and exposure assessment.

The presence of 3-monochloropropane-1,2-diol (3-MCPD) esters and 2-MCPD esters in infant formulas have raised a number of food safety concerns. Here, a dietary exposure assessment was conducted for 3-and 2-MCPD esters in infant formulas available for consumption in Chinese infant and toddlers aged 0-3 years old. This work presents the occurrence data for 3-and 2-MCPD ester in 874 infant formulas purchased in China between 2015 and 2017. The concentrations of 3-MCPD esters ranged from ND to 1.469 mg/kg, with concentrations of 2-MCPD esters ranging from ND to 0.218 mg/kg. The LODs of 3-and 2-MCPD esters were 0.027-0.074 mg/kg. The mean exposures of infants and toddlers to 3-MCPD esters from formulas were lower than the tolerable daily intake (TDI, 2 µg/kg bw/day, established by EFSA), while high exposures (95th percentile) to 3-MCPD esters ranged from 0.907 to 2.520 µg/kg bw/day. On the whole, the health risk of Chinese infant and toddlers exposed to 3-MCPD esters was low, but the health risk of some infants aged 0-6 months with high formula consumption (95th percentile) raises some concern.