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.

Overweight and obesity have increased rapidly in the past few decades in China, and less research has focused on the association between the consumption of ultra-processed foods (UPFs) and overweight or obesity in Chinese adults. The objective of this study was to determine the relationship of UPF consumption with the risk of overweight or obesity in Chinese adults. Residents aged 18 years and above who participated in the nationally representative survey Chinese Food Consumption Survey in 2017–2020 were included in this study. Dietary intake data were collected via non-consecutive three-day 24 h dietary recalls and weighing household foods and condiments. According to the NOVA food classification system, UPFs were classified depending on the purpose and extent of food processing. Multiple logistic regression and multivariate-adjusted restricted cubic spline (RCS) regressions were performed to estimate the association between UPF consumption (categorized into quartiles: quartile 1 (Q1), quartile 2 (Q2), quartile 3 (Q3), and quartile 4 (Q4)) and risk of overweight or obesity. A total of 38,658 adults aged 18 years and above participated in the present study. The prevalence of overweight and obesity in adults was 33.0% (95% CI: 32.91–33.10) and 9.6% (95% CI 9.55–9.67), respectively. After a multivariable adjustment, the risk of overweight or obesity was increased by 10% in Q3 (OR: 1.10, 95% CI: 1.04–1.17) compared to Q1 as a reference. Women (OR: 1.10, 95% CI: 1.01–1.20) and adults living in small and medium-sized cities (OR: 1.13, 95% CI: 1.01–1.26) with higher UPF consumption had higher odds of overweight or obesity. Nevertheless, the effect of higher UPF consumption on the risk of overweight or obesity was relatively weak for overall adults in China. The top three categories of subgroups consumption of UPFs were 1: sugar-sweetened beverages; 2: sauces, cheeses, spreads, and gravies; and 3: ultra-processed breads and breakfast cereals. These findings provide evidence that higher UPF consumption was positively associated with overweight or obesity, which was defined based on Chinese criteria among women and adults living in small and medium-sized cities in China. Further studies, such as intervention trials, are needed to identify the mechanism of correlation between the consumption of UPFs and health-related outcomes in Chinese adults. From a public health perspective, with the prevalence of overweight and obesity growing and the increase in UPF consumption in Chinese adults, it is necessary to promote healthy food intake and a balanced diet through active nutritional education actions for overweight and obesity prevention and control.

Traditional toxicological studies focus on individual compounds. However, this single-compound approach neglects the fact that the mixture exposed to human may act additively or synergistically to induce greater toxicity than the single compounds exposure due to their similarities in the mode of action and targets. Mixture effects can occur even when all mixture components are present at levels that individually do not produce observable effects. So the individual chemical effect thresholds do not necessarily protect against combination effects, an understanding of the rules governing the interactive effects in mixtures is needed. The aim of the study was to test and analyze the individual and combined estrogenic effects of a mixture of three endocrine disrupting chemicals (EDCs), bisphenol A (BPA), nonylphenol (NP) and diethylstilbestrol (DES) in immature rats with mathematical models. In the present study, the data of individual estrogenic effects of BPA, NP and DES were obtained in uterotrophic bioassay respectively, the reference points for BPA, NP and DES were derived from the dose-response ralationship by using the traditional no observed adverse effect (NOAEL) or lowest observed adverse effect level (LOAEL) methods, and the benchmark dose (BMD) method. Then LOAEL values and the benchmark dose lower confidence limit (BMDL10) of single EDCs as the dose design basis for the study of the combined action pattern. Mixed prediction models, the 3 × 2 factorial design model and the concentration addition (CA) model, were employed to analyze the combined estrogenic effect of the three EDCs. From the dose-response relationship of estrogenic effects of BPA, NP and DES in the model of the prepuberty rats, the BMDL10(NOAEL) of the estrogenic effects of BPA, NP and DES were 90(120) mg/kg body weight, 6 mg/kg body weight and 0.10(0.25) μg/kg body weight, and the LOAEL of the the estrogenic effects of three EDCs were 240 mg/kg body weight, 15 mg/kg body weight and 0.50 μg/kg body weight, respectively. At BMDL10 doses based on the CA concept and the factorial analysis, the mode of combined effects of the three EDCs were dose addition. Mixtures in LOAEL doses, NP and DES combined effects on rat uterine/body weight ratio indicates antagonistic based on the CA concept but additive based on the factorial analysis. Combined effects of other mixtures are all additive by using the two models. Our results showed that CA model provide more accurate results than the factorial analysis, the mode of combined effects of the three EDCs were dose addition, except mixtures in LOAEL doses, NP and DES combined effects indicates antagonistic effects based on the CA model but additive based on the factorial analysis. In particular, BPA and NP produced combination effects that are larger than the effect of each mixture component applied separately at BMDL doses, which show that additivity is important in the assessment of chemicals with estrogenic effects. The use of BMDL as point of departure in risk assessment may lead to underestimation of risk, and a more balanced approach should be considered in risk assessment.

The contents of perchlorate and chlorate were determined in a total of 278 samples of infant formulas marketed in China. The associated health risk via infant and young child formulas consumption for 0–36 month old children in China was also assessed. The contents of perchlorate and chlorate were measured by a validated method with LC-MS and the limit of detection (LOD) was 1.5 μg kg⁻¹ and 3.0 μg kg⁻¹ for perchlorate and chlorate, respectively. Perchlorate and chlorate were detected in about 85.8% (median 6.92 μg kg⁻¹, maximum 74.20 μg kg⁻¹) and 99.3% (median 52.80 μg kg⁻¹, maximum 2780 μg/kg) of the samples. The exposures of infant and young children to perchlorate from formulas were lower than the provisional maximum tolerable daily intake (PMTDI, 0.7 μg/kg bw/day), which was established by U.S. Environmental Protection Agency (EPA). The European Food Safety Authority (EFSA) in 2015 also proposed a tolerable daily intake (TDI) of 3 μg/kg bw/day for chlorate based on the mean and average concentrations. Only for infants 0–6 month at the 95th percentile did exposures exceed the TDI of 3 μg/day for chlorate. Therefore, the safety of infant and young child formulas is excellent. To our knowledge, this is the first report to assess the exposure of infant and young child formulas in China to perchlorate and chlorate.