Occurrence, spatial distribution, and risk assessment of perchlorate in tea from typical regions in China.

Perchlorate is a kind of persistent pollutant which occurs widely in the environment. The news of "high content of perchlorate detected in tea exported from China to Europe" has aroused public concerns on perchlorate in tea. However, limited data on its occurrence in tea and health risks for the tea consumers are available. To this end, this study explored the occurrence and spatial distribution of perchlorate based on 747 tea samples collected from the 13 major tea producing regions in China. Perchlorate was detected in 100% of tea samples. The average concentration of perchlorate was 163 µg/kg with the range from 1.2 µg/kg to 3132 µg/kg. From the perspective of spatial distribution, a remarkable difference was observed for perchlorate concentrations in tea samples between different regions (p < 0.0001), and the average concentration of perchlorate from the central China (409 µg/kg) was higher than that from the eastern (90.7 µg/kg) and western (140 µg/kg) regions. However, this study cannot obtain the difference of perchlorate concentrations between different tea categories. Furthermore, a human exposure assessment of perchlorate intake through tea consumption was performed by deterministic and probabilistic risk assessment. The average chronic daily intake (CDI) to perchlorate of Chinese tea consumers was 0.0183 µg/kg bw/day, however, CDI for high tea consumers (99% and 99.9%) was 0.1514-0.4675 µg/kg bw/day. The health risk assessment conducted with a hazard quotient showed that perchlorate exposure through tea consumption was under a safety threshold. Nevertheless, if other dietary exposure pathways were considered, health risks to perchlorate for high tea consumers would be paid attention to.

Legacy and novel brominated flame retardants in animal-derived foods from China Total Diet Study (CTDS): Temporal trends, evidence of substitution, and dietary exposure assessment.

Based on the 6th China Total Diet Study (CTDS) conducted in 2016-2019, the occurrence of both legacy and novel brominated flame retardants (BFRs) was measured in animal-derived foods collected across China. Most BFRs could be frequently detected in food samples, indicating their ubiquity in the environment. Decabromodiphenyl ethane (DBDPE), a typical novel BFR, presented the highest contamination level, whereas legacy BFRs, including decabrominated diphenyl ether (BDE-209), tetrabromobisphenol A (TBBPA), and hexabromocyclododecane (HBCDD), still presented high detection frequencies and relatively abundant proportions in total BFRs. Compared with previous CTDSs conducted from 2007 to 2011, the levels and estimated dietary intakes (EDIs) of most BFRs showed a significant downtrend, which suggested that flame retardant consumption in China has transferred from legacy BFRs to novel BFRs (mainly DBDPE) and from BFRs to other kinds of flame retardants. Based on probabilistic estimation, the median EDIs of mainly used BFRs for the Chinese population ranged from 41.0 to 1.67 × 103 pg/kg bw/day, and meat consumption was the primary source in dietary BFR intake. By conducting the margin of exposure (MOE) approach or comparing with the reference dose (RfD), it can be concluded that daily dietary intakes of BFRs were still unable to cause significant health risks to the general population in China.

Human dietary exposure to bisphenol-diglycidyl ethers in China: Comprehensive assessment through a total diet study.

Despite the widespread use of bisphenol A diglycidyl ether (BADGE) and bisphenol F diglycidyl ether (BFDGE) in various consumer products as protective plasticizer, studies on human dietary exposure to these compounds are scare. In this study, nine bisphenol diglycidyl ethers (BDGEs) including BADGE, BFDGE, and seven of their derivatives were determined in the Chinese adult population based on composite dietary samples collected from the sixth (2016-2019) China total diet study (TDS). Contamination level of nine BDGEs was determined in 288 composite dietary samples from 24 provinces in China. BADGE·2H2O and BADGE are the most frequently detected and BADGE·2H2O presented the highest mean concentration (2.402 µg/kg). The most contaminated food composite is meats, with a mean ∑9BDGEs of 8.203 µg/kg, followed by aquatic products (4.255 µg/kg), eggs (4.045 µg/kg), and dairy products (3.256 µg/kg). The estimated daily intake (EDI) of ∑9BDGEs based on the mean and 95th percentile concentrations are 121.27 ng/kg bw/day and 249.71 ng/kg bw/day. Meats, eggs, and aquatic products are the main source of dietary exposure. Notably, beverages and water, alcohols were the main contributors of dietary exposure to BADGE and BADGE·2H2O, followed by animal-derived foods. Dietary exposure assessment demonstrated that human dietary BDGEs do not pose risks to general population based on the mean and 95th percentile hazard index with < 1. This is the first comprehensive national dietary exposure assessment of BDGEs in Chinese general population.

Integration of probabilistic exposure assessment and risk characterization for perchlorate in infant formula and supplementary food.

Infants are the primary susceptible population to perchlorate exposure-related adverse health effects, while information on their dietary intake of perchlorate via infant food remains limited. This study determined perchlorate in six categories of baby food commodities commonly consumed by 0-36 months infants. A probabilistic approach with Monte Carlo simulation was used to estimate perchlorate's daily intake (EDI) considering uncertainty and variability. Results showed that the average perchlorate concentration in infant food ranged from 3.42 to 22.26 µg/kg. The mean (SD) EDIs of perchlorate were 0.42(0.20), 0.62(0.20), and 0.46(0.14) µg/kg-bw/day for 0-6, 7-12, and 13-36-months infants, respectively. Infant formula was the major contributor (34%-74%) to EDIs of perchlorate in all age groups. Probabilistic risk characterization showed the cumulative probability of EDIs exceeding the RfD (0.70 µg/kg-bw/day) were 6.5%, 37.9%, and 4.5% for 0-6, 7-12, and 13-36-months infants, respectively. The cumulative risk of perchlorate exposure from different infant food intake should be noted.

Occurrence of per- and polyfluoroalkyl substances (PFASs) in raw milk and feed from nine Chinese provinces and human exposure risk assessment.

The per- and polyfluoroalkyl substances (PFASs) are substantially produced and applied in industrial and domestic products, which have recently aroused great public concern for their potential toxicity to humans. In the present study, raw milk (n = 107) and cow feed samples (n = 70) were collected across nine Chinese provinces, in order to investigate the occurrence of PFASs in milk and feed, and the human exposure risk to milk. The concentrations of PFASs are in the range of < method detection limit -9.82 ng/g dw (average: 1.03 ng/g dw) for milk and 0.99-144 ng/g dw (7.68 ng/g dw) for feed. Perfluorobutanoic acid (34.0%) dominates in feed, while perfluorooctanesulfonic acid (67.5%) dominates in milk. No significant positive correlations of PFASs are observed between paired feed and milk (p > 0.05). However, feeds collected around fluorination production area show relatively higher PFAS levels than those from other areas, which also increase PFAS levels in milk. Risk assessment of PFASs through milk consumption is carried out according to evolving reference doses (RfDs). The hazard quotient is more than one for both adults and children when the strictest RfDs are applied. The Monte Carlo Simulation shows that children face higher PFAS exposure risk than adults.

Dietary Exposure to Fumonisins and Health Risk Assessment in the Sixth China Total Diet Study - China, 2015-2020.

INTRODUCTION: Fumonisins are a group of widespread mycotoxins mainly existing in staple foods. Their toxicological effects on humans cause worldwide public health threat. During 2015-2020, the 6th China Total Diet Study (TDS) was conducted to study the dietary exposure to fumonisins in the Chinese adult population. METHODS: Fumonisins were analyzed by LC-MS/MS in 288 composite dietary samples collected from 24 provincial-level administrative divisions. After combining the national consumption data with analytical results, estimated daily intakes (EDIs) were assessed and compared with health-based guide values (HBGV). RESULTS: In the 6th China TDS, the highest fumonisin B (FBs) levels were found in staple foods/cereals among the 12 food categories. EDI of FBs was 104.9 ng/kg of body weight (bw)/day at the upper bound accounting 5.25% of the provisional maximum tolerable daily intake set by Joint Food and Agriculture Organization/World Health Organization Expert Committee on Food Additives. Among the 12 food categories, cereals and cereal products were the greatest contributor to FB exposure at 95%. CONCLUSION: Although the estimated exposure to FBs in the 6th China TDS were well below the HBGV for FBs in general, it was 2 times higher than the exposure in the 5th China TDS. Furthermore, the exposure to FB3 has increased remarkable and is worth further attention in China.

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.

Nationwide Biomonitoring of Neonicotinoid Insecticides in Breast Milk and Health Risk Assessment to Nursing Infants in the Chinese Population.

Presently, the potential health risks of neonicotinoid insecticides (neonics) are now receiving much attention, but no data regarding the exposure of infants to neonics via human breast milk intake have been reported. In this study, a nationwide survey was conducted during the period of 2017-2019, wherein 97 pooled breast milk samples were collected from 3570 lactating women of 23 provinces in China. Nationally, acetamiprid-N-desmethyl was the most predominant compound, accounting for 61.2% of the total amount of neonics, followed by imidacloprid (15.6%). The concentration of the sum of acetamiprid and its metabolite acetamiprid-N-desmethyl in breast milk was positively correlated with corresponding dietary exposure, while no statistically significant association between the other neonic levels in breast milk and dietary exposure was found. The cumulative daily intakes of neonics (9.40-249 ng kg-1 of body weight day-1) were estimated for breastfed infants, indicating a minuscule risk to Chinese infants from neonic exposure via breastfeeding.

Temporal variation analysis and risk assessment of neonicotinoid residues from tea in China.

The extensive use of neonicotinoids (NEOs) has caused the release of wide-ranging of residues to the environment and food, and their potential health risks are now receiving more attention. In this study, three surveys were conducted to obtain the overall profiles of NEO residue levels (seven NEOs and one metabolite) in Chinese tea over a period of seven years. A total of 726 tea samples were tested, and nearly 87% of the samples were found to have detectable NEO residues. The overall average detection frequency of acetamiprid was the highest, reaching 73%. Imidacloprid residues in 4.6% of the samples exceeded the Chinese maximum residue limits, whereas clothianidin and nitenpyram had been detected in Chinese tea samples since 2014. The applications of thiacloprid and thiamethoxam gradually increased, and some tea samples with high residue levels appeared in China. These findings signal the replacement of new and old varieties of NEOs in China. Both long- and short-term cumulative exposures to NEOs were calculated based on optimistic and pessimistic models recommended in the EFSA guidelines. In the three survey periods, the average total imidacloprid-equivalent concentrations were 484.63, 1713.36, and 1148.34 µg/kg, respectively. Combined with the refined point estimates and probabilistic models used in this study, the hazard quotients of NEO residues in tea for Chinese tea consumers were found to be low and within the bounds of safety.

Polychlorinated naphthalenes in human milk: Health risk assessment to nursing infants and source analysis.

Polychlorinated naphthalenes are teratogenic environmental contaminants. Mother milk is the most important food for nursing infants. The World Health Organization actively promotes breastfeeding for its immunological, psychological, and economic advantages. We firstly measured concentrations of polychlorinated naphthalenes in human milk from 19 provinces in China and estimated their potential health risks to nursing infants and their possible sources. Concentrations ranged from 211.07 to 2497.43 pg/g lipid. The high prevalence of highly toxic hexachlorinated naphthalenes (Hexa-CN66/67) in human milk samples indicated a higher health risk in the sampling areas. Cancer risk posed to nursing infants was not significant, but potential non-carcinogenic adverse health effects were suggested and should be emphasized in some sampling areas. Unintentional emission of polychlorinated naphthalenes from industries that employ thermal processes appears to be the main source for PCNs in human milk in most sampling areas. Correlation analysis also suggested PCNs as impurities in polychlorinated biphenyl mixtures as a previously unrecognized source of polychlorinated naphthalenes in human milk.

Polybrominated diphenyl ethers and novel brominated flame retardants in human milk from the general population in Beijing, China: Occurrence, temporal trends, nursing infants' exposure and risk assessment.

The levels of eight polybrominated diphenyl ether (PBDE) congeners, and six novel brominated flame retardants (NBFRs) were determined in human milk collected from Beijing, China in 2014. The tested 111 samples were collected from 37 mothers, and each donor provided one milk sample per month for 3 months after childbirth. Levels of ∑PBDEs (total tri- to deca-BDEs) were in the range of 0.288 to 22.2 ng g-1 lw (lipid weight). BDE-209, with a median level of 2.2 ng g-1 lw, was the predominant congener. Decabromodiphenyl ethane (DBDPE), as an NBFR and a substitute for deca-BDE, was found to be the most abundant BFR in all tested human milk (median:5.96 ng g-1 lw). This result might suggest that the predominantly consumed BFRs in China have changed from PBDEs to PBDE substitutes. Additionally, a comparison to our previous studies conducted in 2005 and 2011 revealed that levels of tri- to hepta-BDEs showed significant reduction from 2005 to 2014, whereas levels of BDE-209 showed no significant variation from 2011 to 2014. Temporal trends of BFR levels over the three months of lactation were also investigated, and no significant changes were found in concentration with time over the three months lactation. For nursing infants up to 6 months old, the median lower bound of daily BFR intakes via human milk ingestion ranged from zero for 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE) and 1,2-bis(2,4,6-tribromophenoxy)-ethane (BTBPE) to 18.7 ng kg-1 bodyweight day-1 for DBDPE. Although the daily dietary BFR intake for nursing infants was found to be much higher than that for adults, the risk assessment evaluated by the margin of exposure (MOE) approach revealed that dietary BFR intake for nursing infants was unlikely to pose significant health risks.

[Assessment and application for the results of global intercalibration study of typical perfluoroalkyl substances in foods and human matrices].

OBJECTIVE: To analyze the result of global intercalibration study of typical perfluoroalkyl substances( PFASs) and their typical isomers in foods, human milk and serum from 2010 to 2017 and discuss the application of the result in quality assurance and control. METHODS: Z-scores were employed to assess the result of PFASs and their typical isomers from global intercalibration study. Combined with the concentrations of the samples, we have also analyzed the key point of the method. RESULTS: The absolute values of the Z-scores of most PFASs and their typical isomers were less than 1, indicating that the concentrations determined by our laboratory were satisfactory. CONCLUSION: The problems in the method could be found in time by participating in the global intercalibration study. Therefore we can improve the method to ensure the accuracy of the data and provide the effective technical support for determining the levels of PFASs and their typical isomers in foods, human milk and serum in China.

Short- and medium-chain chlorinated paraffins in aquatic foods from 18 Chinese provinces: Occurrence, spatial distributions, and risk assessment.

Short-chain chlorinated paraffins (SCCPs) are classed as persistent organic pollutants and were included in the Stockholm Convention in May 2017. Large amounts of chlorinated paraffins (CPs) are produced in China than in any other countries. CPs can be released into the environment while being produced and used, and can bioaccumulate in aquatic biota and be ingested by humans. Dietary intake is the main route through which humans are exposed to CPs. It has previously been found that persistent organic pollutant concentrations are usually higher in aquatic foods than in other foods. The risk of human exposure to SCCPs in aquatic foods should therefore be of concerns. However, SCCP concentrations in aquatic foods have not been systematically studied. A total of 1620 aquatic food samples were collected, and 18 pooled samples were analyzed by two-dimensional gas chromatography coupled with electron-capture negative-ionization time-of-flight mass spectrometry. The mean SCCP and MCCP concentrations were 1472 and 80.5ng/gwet weight, respectively. The dominant SCCP and MCCP congener groups were C10Cl6-7 and C14Cl7-8, respectively. The concentrations were much higher than those have been found in aquatic foods in other countries. The CP concentrations in the samples consumed by local people from eastern and southern China were higher than the concentrations in samples from central and western China. Risk assessment results indicated that SCCPs and MCCPs in aquatic foods do not pose significant risks to residents of China.

Legacy and emerging brominated flame retardants in China: A review on food and human milk contamination, human dietary exposure and risk assessment.

Brominated flame retardants (BFRs) are a large group of widely used chemicals, which have been produced and used since 1970s. As a consequence of substantial and long-term usage, BFRs have been found to be ubiquitous in humans, wildlife, and abiotic matrices around the world. Although several reports have reviewed BFRs contamination in general, none have focused specifically on foods and human milk, and the corresponding dietary exposure. Foods (including human milk) have long been recognized as a major pathway of BFRs intake for non-occupationally exposed persons. This review summarizes most available BFRs data in foods and human milk from China in recent years, and emphasizes several specific aspects, i.e., contamination levels of legacy and emerging BFRs, dietary exposure assessment and related health concerns, comparison between various BFRs, and temporal changes in BFRs contamination.

Dietary exposure assessment of Chinese population to tetrabromobisphenol-A, hexabromocyclododecane and decabrominated diphenyl ether: Results of the 5th Chinese Total Diet Study.

Based on the 5th Chinese Total Diet Study (TDS) carried out in 2011, the dietary exposure of Chinese population to three currently used brominated flame retardants (BFRs), tetrabromobisphenol A (TBBPA), hexabromocyclododecane (HBCD) and decabrominated diphenyl ether (BDE-209), was estimated and the related health risks were assessed. Levels of the three BFRs were determined in 80 composite samples from four animal-origin food groups. The average levels of BFRs in various food groups ranged from 0.671 to 5.76 ng/g lipid weight (lw). The levels of TBBPA were lower than those of HBCD but higher than those of BDE-209. Moreover, average contamination levels of TBBPA and HBCD in TDS 2011 were found to be 3 to 30 times higher than those observed in TDS 2007 in the four food groups, indicating an increase in TBBPA and HBCD in the environment during 2007-2011. The average estimated daily intakes (EDIs) of TBBPA, HBCD and BDE-209 via food consumption for a "standard Chinese man" were 1.34, 1.51 and 0.96 ng/kg bw/day, respectively. Meat and meat products were found to be the major contributor to the daily dietary intake because the consumption of meat and meat products were significantly higher than that of other food groups in China. In comparison, the levels and EDIs of BFRs in this study were found to be higher than those in most studies worldwide. However, the large margin of exposure (MOE), with at least 1.1 × 105 calculated following the European Food Safety Authority (EFSA) approach, indicates that the estimated dietary exposure to these three BFRs is unlikely to raise significant health concerns. In addition, a comparison between the contamination levels of TBBPA, HBCD, BDE-209 and some novel BFRs in food samples from TDS 2011 indicated an obvious shift in the industrial production and usage pattern between PBDE and non-PBDE BFRs in China.

A national survey of tetrabromobisphenol-A, hexabromocyclododecane and decabrominated diphenyl ether in human milk from China: Occurrence and exposure assessment.

A national survey of three currently used brominated flame retardants (BFRs), tetrabromobisphenol A (TBBPA), hexabromocyclododecane (HBCD) and decabrominated diphenyl ether (BDE-209) in human milk was conducted in 2011. Human milk from 16 provinces of China were collected, pooled and measured. The estimated daily intake (EDI) via human milk ingestion for nursing infant and the related health risks were evaluated. The median levels of TBBPA, HBCD and BDE-209 were 1.21, 6.83 and 0.556ng/g lipid weight (lw), respectively. Levels of BDE-209 were lower than those of TBBPA, indicating that the production and application of deca-BDE in China has been below that of TBBPA after the restriction of PBDEs. Moreover, contamination levels of TBBPA and HBCD in this survey were higher than those observed in last national survey conducted in 2007, indicating an increase of TBBPA and HBCD in the environment from 2007 to 2011. The mean estimated daily intakes (EDIs) of TBBPA, HBCD and BDE-209 via human milk for 1-6months old infant were 39.2, 51.7 and 3.65ng/kgbw/day, respectively. For risk assessment, margin of exposure (MOE) was calculated by comparing the BMDL10 (benchmark dose lower confidence limit for a benchmark response of 10%) to the EDI of each BFR. Large MOEs indicates that the estimated dietary exposure to these three BFRs for nursing infant is unlikely to raise significant health concerns. Compared with some currently used novel BFRs which also measured in this survey, higher contamination levels were found in some non-PBDE BFRs, indicating that the consumption pattern of BFRs has shifted from PBDEs to non-PBDE BFRs in China.

Novel brominated flame retardants in food composites and human milk from the Chinese Total Diet Study in 2011: Concentrations and a dietary exposure assessment.

On the basis of the fifth Chinese total diet study (TDS) performed in 2011, the dietary exposure of the Chinese population to novel brominated flame retardants (NBFRs) was assessed. Six NBFRs were determined in 80 composite samples from four animal origin food groups and 29 pooled human milk samples. Based on gas chromatography-negative chemical ionization mass spectrometry (GC-NCI/MS) analysis, the levels of the total NBFRs ranged from

Assessment of dietary intake of polychlorinated dibenzo-p-dioxins and dibenzofurans and dioxin-like polychlorinated biphenyls from the Chinese Total Diet Study in 2011.

The concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) as well as dioxin-like polychlorinated biphenyls (dl-PCBs) were measured in food samples from the fifth Chinese Total Diet Study (TDS) performed in 2011. A total of 152 composite samples from various food groups were analyzed by high resolution gas chromatography-high resolution mass spectrometer (HRGC-HRMS). The dietary intakes of PCDD/Fs and dl-PCBs were subsequently estimated for the adult from various regions in China. The mean dietary intake of PCDD/Fs and dl-PCBs was 20.1 pg TEQ kg(-1) bw month(-1) (WHO-TEF of 1998) within a range of 4.2 pg TEQ kg(-1) bw month(-1) to 53.7 pg TEQ kg(-1) bw month(-1) which were all much lower than the provisional tolerable monthly intake (PTMI) established by Joint FAO/WHO Expert Committee on Food Additives (JECFA). By comparing with results from previous Chinese TDS, a decline of the average dietary intake was observed from 2000 to 2011, but a notable elevation was observed in some regions partly stem from increasing contamination levels in certain foods.

Assessment on dioxin-like compounds intake from various marine fish from Zhoushan Fishery, China.

Sea fish consuming is an important intake source of dioxin-like compounds, especially for the coastal residents. To assess the intake levels of these contaminants from sea fish and to provide risk-based consumption advice, concentrations of 17 polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and 12 dioxin-like polychlorinated biphenyls (dl-PCBs) were measured in 32 commonly consumed fish species from Zhoushan Fishery, China. Due to the different accumulation influenced by fat content, feed habits and living zone in the sea area, the levels of PCDDs, PCDFs and dl-PCBs in different fish species varied significantly ranging from 0.002 to 0.078pg WHO-TEQ/g fresh weight, from 0.002 to 0.553pg WHO-TEQ/g fresh weight and from 0.003 to 2.059pg WHO-TEQ/g fresh weight, respectively. Based on mean fish consuming rate in China, the estimated maximum possible dioxin-like compounds intake through different fish species ranged from 0.26 to 65.61pgTEQkg(-1)bwmonth(-1). Bullet mackerel has the highest monthly intake level which was much higher than other fish species and very close to the provisional tolerable monthly intake (70pgTEQkg(-)(1)bwmonth(-)(1)) proposed by the Joint FAO/WHO Expert Committee on Food Additives. Hence, comparing to other fish species, the consumption of Bullet mackerel from Zhoushan Fishery should be cautious to reduce the potential health risk.