Study on the bioaccessibility and bioavailability of perchlorate in different food matrices in vitro

Bio-accessibility and bio-availability evaluation of each arsenic species existing in various edible seaweeds in vitro and in vivo for arsenic risk assessment

Seaweeds consumption is one of main internal exposure sources of arsenic for human. However, the absence of representative bio-availabilities of arsenic species makes the accurate assessment of arsenic health risk originating from seaweeds consumption impossible. Herein, the arsenic species in various seaweeds collected from Fujian of China were investigated, and the bio-accessibilities/bio-availabilities of arsenic species existing in seaweeds were evaluated in vitro and in vivo. Results revealed that in vitro bio-availabilities of arsenic species presenting in seaweeds, which obtained with Caco-2 cells, were lower than those of pure arsenic standards, and varied with order of inorganic arsenic (iAs) > dimethylarsinic acid (DMA) ≈ arsenobetaine (AsB) > arsenosugars. During gastrointestinal digestion of mice, As5+ was partly methylated into monomethylarsonic acid (MMA) and DMA, which makes the in vivo bioavailability of iAs (⁓31.8 %) obtained with mouse metabolic experiment is much higher than its in vitro bio-availability (⁓10.3 %). The in vivo bio-availabilities of DMA and total arsenic (tAs) are similar to their in vitro bio-availabilities. As the dominant arsenic species in most seaweeds, arsenosugars have an ⁓0.0 % of in vivo bioavailability and only a ⁓3.7 % of in vitro bioavailability. The simulated calculation of target hazard quotient (THQ) and target cancer risk (TR) revealed that the arsenic risk originating from seaweeds was greatly degraded by taking into consideration of arsenic species and bio-availabilities, and all seaweeds collected from Fujian are safety for consumption. The simulated calculation also revealed that arsenic risk of seaweeds can be also more accurately assessed based on tAs together with bioavailability, which provides a simple but accurate and protective method for the risk assessment of arsenic originating from seaweeds. Our work provides the possible representative bio-availabilities of arsenic species presenting in seaweeds for accurately assessing arsenic risk of seaweeds, and novel insights into the bio-availabilities of arsenic in animal.

Chemical Profile Characterization of Fruit and Vegetable Juices after Fermentation with Probiotic Strains

Lactic acid bacteria (LAB) are widely applied for fermentation purposes in dairy and non-dairy food matrices with beneficial technological and health-promoting properties. This study describes the effect of two lactic acid bacteria, namely, Lactiplantibacillus paracasei SP5 and Pediococcus pentosaceus SP2, on the phenolic profiles, antioxidant activities, total phenolic content (TPC), carotenoid content, and sensorial profile of two different mixed fruit juices. After 48 h of fermentation, both LABs retained viability over 9 Log CFU/mL in both juices. The TPC, zeaxanthin + lutein, β-carotene content, and antioxidant activity (AA) were elevated for both LABs and mixed juices after 48 h of fermentation compared to control samples. Regarding the phenolic profile, both juices exhibited a significant decrease in chlorogenic acid levels, while quinic acid and tyrosol concentrations showed notable increases.

Exposure and Health Risk Assessment of Heavy Metal in Crayfish from the Middle and Lower Reaches of the Yangtze River

Red swamp crayfish (Procambarus clarkia) is an exposed species to heavy metals due to their lifestyle of direct contact with sediments. Based on the complete crayfish industry, we focus on the presence of heavy metals in crayfish from different circulation links, which provides a new idea for the investigation of heavy metals in food. To analyze the exposure levels of heavy metals in crayfish during aquaculture and circulation, the five elements (Cd, Pb, Hg, Cr, Cu) in crayfish from 126 sampling sites were investigated. Cultured environmental samples were collected for Spearman correlation analysis. Monte Carlo simulation was used to analyze the uncertain health risks of heavy metals in crayfish. The results indicated that the average heavy metal concentrations in crayfish were all below the limit threshold values. The hepatopancreas was the main target organ for heavy metal accumulation (Cd: 0.3132 mg/kg; Pb: 0.0258 mg/kg; Hg: 0.0072 mg/kg; Cr: 0.1720 mg/kg; Cu: 10.6816 mg/kg). The positive correlation of heavy metal content between crayfish and sediments was not significant under the crayfish-rice coculture model. The 95th HI values for adults and children ranged from 0.022 to 0.042 and 0.071 to 0.137, well below 1, indicating that heavy metals do not pose a noncarcinogenic risk to humans. The potential carcinogenic risk of Cd and Cr in crayfish should be taken seriously, as the 95th CR values for children have reached 4.299 × 10-5 and 6.509 × 10-5, respectively.

Bioaccessibility data of potentially toxic elements in complementary foods for infants: A review

The introduction of complementary foods (CFs) is a critical step in an infant's transition to solid foods, providing essential nutrients beyond breast milk. However, CFs may contain potentially toxic elements (PTEs), such as arsenic and cadmium that pose health risks to infants. In this context, understanding the bioaccessibility of PTEs is vital as it determines the fraction of a contaminant released from the food matrix and available for absorption in the gastrointestinal tract. Efforts have been made to standardize the assessment methodology for bioaccessibility, ensuring consistent and reliable data. Moreover, regulatory agencies have established guidelines for PTEs levels in food. However, important gaps still exist, which motivates many research opportunities on this topic.

Refining health risk assessment of arsenic in wild edible boletus from typical high geochemical background areas: The role of As species, bioavailability, and enterotoxicity

Arsenic (As) is easily accumulated in wild Boletus. However, the accurate health risks and adverse effects of As on humans were largely unknown. In this study, we analyzed the total concentration, bioavailability, and speciation of As in dried wild boletus from some typical high geochemical background areas using an in vitro digestion/Caco-2 model. The health risk assessment, enterotoxicity, and risk prevention strategy after consumption of As-contaminated wild Boletus were further investigated. The results showed that the average concentration of As was 3.41-95.87 mg/kg dw, being 1.29-56.3 folds of the Chinese food safety standard limit. DMA and MMA were the dominant chemical forms in raw and cooked boletus, while their total (3.76-281 mg/kg) and bioaccessible (0.69-153 mg/kg) concentrations decreased to 0.05-9.27 mg/kg and 0.01-2.38 mg/kg after cooking. The EDI value of total As was higher than the WHO/FAO limit value, while the bioaccessible or bioavailable EDI suggested no health risks. However, the intestinal extracts of raw wild boletus triggered cytotoxicity, inflammation, cell apoptosis, and DNA damage in Caco-2 cells, indicating existing health risk assessment models based on total, bioaccessible, or bioavailable As may be not accurate enough. Given that, the bioavailability, species, and cytotoxicity should be systematically considered in accurate risk assessment. In addition, cooking mitigated the enterotoxicity along with decreasing the total and bioavailable DMA and MMA in wild boletus, suggesting that cooking could be a simple and effective way to decrease the health risks of consumption of As-contaminated wild boletus.

Sensor technologies for the detection and monitoring of endocrine-disrupting chemicals

Endocrine-disrupting chemicals (EDCs) are a class of man-made substances with potential to disrupt the standard function of the endocrine system. These EDCs include phthalates, perchlorates, phenols, some heavy metals, furans, dimethoate, aromatic hydrocarbons, some pesticides, and per- and polyfluoroalkyl substances (PFAS). EDCs are widespread in the environment given their frequent use in daily life. Their production, usage, and consumption have increased many-fold in recent years. Their ability to interact and mimic normal endocrine functions makes them a potential threat to human health, aquatics, and wild life. Detection of these toxins has predominantly been done by mass spectroscopy and/or chromatography-based methods and to a lesser extent by advanced sensing approaches such as electrochemical and/or colorimetric methods. Instrument-based analytical techniques are often not amenable for onsite detection due to the lab-based nature of these detecting systems. Alternatively, analytical approaches based on sensor/biosensor techniques are more attractive because they are rapid, portable, equally sensitive, and eco-friendly. Advanced sensing systems have been adopted to detect a range of EDCs in the environment and food production systems. This review will focus on advances and developments in portable sensing techniques for EDCs, encompassing electrochemical, colorimetric, optical, aptamer-based, and microbial sensing approaches. We have also delineated the advantages and limitations of some of these sensing techniques and discussed future developments in sensor technology for the environmental sensing of EDCs.

Assessment of lipid composition and eicosapentaenoic acid/docosahexaenoic acid bioavailability in fish oil obtained through different enrichment methods

In this study, we analyzed the eicosapentaenoic acid/docosahexaenoic acid (EPA/DHA) lipid composition of fish oil obtained through enzymatic treatment, fractional distillation and silica gel column purification, and further assessed EPA/DHA bioavailability. Lipid subclass composition information was obtained through ultra-performance liquid chromatography-electrospray ionization tandem mass spectrometry (UPLC-ESI-MS/MS), and bioavailability tests were performed using the Caco-2 cell monolayer model. Results showed that enzymatic treatment improved the incorporation of EPA/DHA as diacylglycerol (DG) while silica gel column chromatography enriched the content of EPA/DHA as phosphatidylglycerol (PG) (12.58%) and phosphatidylethanolamine (PE) (4.99%). Furthermore, increasing the purity of EPA/DHA could improve its bioavailability and after 24 incubation, binding forms of triglyceride (TG) was superior to ethyl ester (EE) (p < 0.05) at the same purity level. Those findings are helpful to provide research basis for exploring the bioactivity of fish oil.

Health risk assessment of perchlorate and chlorate in red swamp crayfish (Procambarus clarkii) in China

Perchlorate and chlorate are both strong oxidants and thyroid toxicants that are widely distributed in soil, water and human foods. The red swamp crayfish (Procambarus clarkii) is a common aquatic organism that is popular in Chinese culinary dishes. Dietary intake is the main route of human exposure to perchlorate and chlorate, though the health risks of crayfish consumption are unknown. Thus, this study investigated the quantities of perchlorate and chlorate in red swap crayfish from sampling sites in five provinces located near the Yangtze River in China, along with the associated health risks of consuming this species. Perchlorate was detected in 55.6-100 % of crayfish samples in each sampling location, and chlorate was found in 100 % of samples cross all sites. Concentrations of perchlorate in crayfish from upstream provinces (Hubei, Hunan and Jiangxi) were higher than those from downstream provinces (Anhui and Jiangsu). Perchlorate and chlorate concentrations were positively correlated in crayfish, suggesting that chlorate may be a degradation byproduct of perchlorate. The quantities of both pollutants in hepatopancreas tissue were higher than in muscle tissues (p < 0.05), such that we do not recommend ingesting crayfish hepatopancreas. Hazard quotient (HQ) values for chlorate in crayfish were <1 across all provinces, suggesting no potential health risk of chlorate exposure through crayfish consumption. However, perchlorate concentrations in crayfish from the Jiangxi province had an associated HQ value >1, suggesting potential risks for human health. These results will be useful in informing mitigation measures aimed at reducing perchlorate exposure associated with crayfish consumption.

Trends in the Exposure, Distribution, and Health Risk Assessment of Perchlorate among Crayfish in the Middle and Lower Reaches of the Yangtze River

Perchlorate is a well-known thyroid-disrupting chemical as well as an extremely stable inorganic pollutant widely distributed in the environment. Therefore, perchlorate posts potential risks to the environment as well as human health. Crayfish is a dominant aquatic food with increasing consumption levels in recent years. It is crucial to evaluate the accumulation of perchlorate with well-water-soluble properties in crayfish and to assess its health risks. In our present study, we obtained crayfish samples from cultivated ponds and markets based on the regions of the Middle and Lower Reaches of the Yangtze River. The perchlorate concentration was measured in all 206 samples using ultra-high performance liquid chromatography coupled with mass spectrometry (UPLC–MS). Monte Carlo simulation was used to perform health risk assessments. The results indicated that perchlorate levels ranged from 7.74–43.71 μg/kg for cultivated crayfish and 4.90–16.73 μg/kg for crayfish sold in markets. The perchlorate accumulation mainly occurred in exoskeleton parts. All the HQ values were remarkable, at less than one—indicating that perchlorate exposure through the ingestion of crayfish does not pose an appreciable risk to human health.

Targeted Lipidomics Reveal the Effect of Perchlorate on Lipid Profiles in Liver of High-Fat Diet Mice

Perchlorate, commonly available in drinking water and food, acts on the iodine uptake by the thyroid affecting lipid metabolism. High-fat diets leading to various health problems continually raise public concern. In the present study, liver lipid metabolism profiles and metabolic pathways were investigated in C57BL/6J mice chronically exposed to perchlorate using targeted metabolomics. Mice were fed a high-fat diet and treated orally with perchlorate at 0.1 mg/kg bw (body weight), 1 mg/kg bw and 10 mg/kg bw daily for 12 weeks. Perchlorate induced disorders of lipid metabolism in vivo and hepatic lipid accumulation confirmed by serum biochemical parameters and histopathological examination. There were 34 kinds of lipid in liver detected by UHPLC-MS/MS and key metabolites were identified by multivariate statistical analysis evaluated with VIP > 1, p-value < 0.05, fold change > 1.2 or < 0.8. Perchlorate low, medium and high dose groups were identified with 11, 7 and 8 significantly altered lipid metabolites compared to the control group, respectively. The results of the metabolic pathway analysis revealed that the differential metabolites classified into different experimental groups contribute to the glycerophospholipid metabolic pathway. These findings provide insights into the effects of perchlorate on lipid metabolism during long-term exposure to high-fat diets and contribute to the evaluation of perchlorate liver toxic mechanisms and health effects.

Accumulation and distribution of perchlorate in spinach and chard growing under greenhouse: Implications for food safety in baby foods commodities

Very little information is available with regards to the bioavailability of perchlorate in spinach or chard used in the production of baby foods commodities. In the present study, the uptake and accumulation of perchlorate were compared under two different treatments (T1: 1 and T2: 10 mg L^-1 ClO₄^-). Our results indicate that spinach has a higher capacity to accumulate perchlorate than chard (p < 0.0185). Concentrations of perchlorate in leaves, stems and roots (leaves > stem > roots) all gradually increased (p < 0.0001) as vegetable growing and treatment (T2 > T1). No significant differences were found between the control and T1. The daily intake for perchlorate (control) is below the proposed international standard, however, it was exceeded in T1 and T2. The results suggested that perchlorate is actively accumulate in high concentrations in vegetables used in the production of baby food commodities and the exposure of perchlorate via the food consumption (baby foods) was evaluated as not safe.

Exposure to perchlorate, nitrate and thiocyanate was associated with the prevalence of cardiovascular diseases

AIMS

To determine the association between urinary levels of perchlorate, nitrate and thiocyanate, and the prevalence of cardiovascular diseases (CVD) among general population.

METHODS

A total of 16, 570 participants were enrolled from the National Health and Nutrition Examination Surveys (NHANES). Urinary levels of perchlorate, nitrate and thiocyanate were measured using ion chromatography coupled with electrospray tandem mass spectrometry. Multivariable linear regressions and logistic regressions were performed to explore the associations of exposure to perchlorate, nitrate and thiocyanate, and the prevalence of total and specific CVD, including chronic heart failure (CHF), coronary heart disease (CHD), angina, heart failure and stroke. Restricted cubic splines were used to explore the nonlinearity.

RESULTS

Participants with CVD had a lower urinary level of nitrate and thiocyanate (all P < 0.001). A null association between urinary perchlorate and total CVD or specific CVD was observed. Comparing with the lowest quartile, the highest quartile of urinary nitrate was independently associated with a decreased presence of total CVD (odds ratio [OR] 0.66, 95% confidence interval [CI] [0.53, 0.82]), CHF (OR 0.48, 95% CI [0.33, 0.71]), and stroke (OR 0.63, 95%CI [0.45, 0.88]). In addition, per one-fold increasement of urinary nitrate decreased a 0.15-fold prevalence of total CVD, 0.29-fold prevalence of CHF, and 0.16-fold prevalence of stroke. However, for urinary thiocyanate, we found that the 2nd and 3rd quartile were associated with total CVD, the 2nd quartile associated with heart attack, and the 2nd, 3rd and 4th quartile associated with stroke. What's more, restricted cubic splines confirmed that the relation between urinary nitrate and CVD was linear (P for nonlinearity = 0.242) and the inverse relation between urinary thiocyanate and CVD was nonlinear (P for nonlinearity < 0.001).

CONCLUSION

In the general population, low levels of nitrate were linearly while thiocyanate were nonlinearly associated with an increased presence of cardiovascular diseases.

Bioavailability Evaluation of Perchlorate in Different Foods In Vivo: Comparison with In Vitro Assays and Implications for Human Health Risk Assessment

Perchlorate in various foods continuously arouses public health concern. Bioavailability is a critical parameter to better estimate perchlorate exposure from diets. In this study, perchlorate bioavailability in five foods was determined in an in vivo mouse model and compared with in vitro bioaccessibility/bioavailability. The estimated in vivo perchlorate bioavailability for different foods ranged from 18.01 ± 4.53% to 45.60 ± 7.11%, with the order lettuce > pork > rice > milk powder > soybean. Moisture, fiber, and fat in foods were identified as critical factors affecting perchlorate bioavailability (correlation r = 0.71, 0.52, and -0.67, respectively). Linear regression analysis revealed that the in vitro perchlorate bioavailability determined using the Caco-2 cell model has the potential to estimate the in vivo perchlorate bioavailability in foods (R² = 0.67, slope = 1.33, and y intercept = 4.99). These findings provide insights into the effects of the food matrices on perchlorate bioavailability and could contribute to decrease the uncertainty regarding perchlorate dietary exposure risk assessment.

Determination of perchlorate in tea using SERS with a superhydrophobically treated cysteine modified silver film/polydimethylsiloxane substrate

Perchlorate is a new type of persistent pollutant, which interferes with the synthesis and secretion of thyroxine and affects human health. The EU's limit for perchlorate in tea is 750 μg kg^-1. The surface-enhanced Raman scattering (SERS) technique has the characteristics of a simple pretreatment method, rapid detection, high sensitivity, high specificity and great stability in the detection of perchlorate. This study proposed a novel superhydrophobic SERS substrate, which can be used to detect perchlorate in tea. Firstly, a chemical deposition method was used to deposit a silver film on the surface of a thin layer of polydimethylsiloxane. After drying, the substrate was immersed in 1H,1H,2H,2H-perfluorodecyltriethoxysilane aqueous solution for 15 hours to make the surface of the substrate superhydrophobic. Then cysteine molecules were deposited on the surface of the silver film/polydimethylsiloxane by incubation. The superhydrophobic surface has a unique enrichment effect on the highly diluted solution, and perchlorate has a strong affinity for the amino group of cysteine. We collected the Raman spectra of 9 gradient concentrations (1-100 μmol L^-1) of perchlorate-spiked tea samples on the hydrophobic substrate, and a linear model of the relationship between the SERS spectral intensity and the concentrations of perchlorate in tea was established. This method reached a good limit of detection of 0.0067 μmol L^-1 (0.82 μg kg^-1) in tea, which showed that the developed sensor has high sensitivity and could be used as a fast and simple technique for quantitative detection of perchlorate based on SERS technology.