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ObjectiveTo assess the risk of exposure in the population in 7 provinces and cities in China， the intake of glutamates （calculated for glutamic acid） in Chinese restaurant diners was calculated and compared with the recommended intake.MethodsA multi-stage stratified and population-proportional whole-group random sampling method was used to randomly select condiments in seven provinces/municipalities： Beijing， Chongqing， Liaoning， Shandong， Guangxi， Jiangsu， and Shaanxi. Ultra-performance liquid chromatography-tandem mass spectrometry method was used to determine the glutamate content of collected condiments. The glutamate intake was calculated based on individual consumption and body weight data obtained during the investigation based on a simple distribution model of restaurant diners.ResultsThe highest levels of glutamates were found in flavoring agents and enhancers， followed by chicken essence/chicken powder， solid compound condiments other than chicken essence， liquid compound condiments， soy sauce， semi-solid compound condiments based on animal ingredients， spices， and brewing preparation sauces， etc. The lowest levels of glutamates were found in salt and salt substitutes. The mean glutamate intake of a meal for restaurant diners was 47.87 mg/kg·BW， accounting for 39.89% of the ADI set by JECFA. The mean glutamate intake for a day was 61.33 mg/kg·BW when considering food consumed outside the restaurant during the day， accounting for 51.11% of the ADI. Among diners of different restaurant sizes， medium-sized restaurants had the highest intake of glutamates during a meal， with a median intake of 44.46 mg/kg·BW， followed by large restaurants and small restaurants， with significant differences （P0.05）， and the mean values as a proportion of ADI were

ObjectiveTo establish the risk assessment method of food disinfectant with the peroxyacetic acid disinfectant for poultry slaughtering and processing as the model disinfectant.MethodsReferring to the risk assessment methods of food disinfectants from international organizations， the risk assessment method of food disinfectants suitable for China was established by considering the health effects， efficacy， and antimicrobial resistance. The safety of peroxyacetic acid disinfectant used for carcass disinfection during poultry slaughtering was assessed using the established method.ResultsUnder the setting condition， the health risk of the ingredients of the peroxyacetic acid disinfectant （peroxyacetic acid， acetic acid， hydrogen peroxide， and 1-hydroxyethylidine-1，1-diphosphonic acid） and the disinfection byproducts and reaction products after the treatment did not need priority attention. Based on the literature search results， the use of peroxyacetic acid disinfectants may not lead to decreased efficacy of fungicides and/or be associated with antimicrobial resistance.ConclusionThe risk assessment method for food disinfectants in China was established， which can be used as a methodological reference for the safety assessment of the new food disinfectant products in the future.

Risk assessment of non-intentionally added substances， including oligomers， in food contact materials is of great importance for ensuring food safety. Research articles and risk assessment reports at home and abroad were collected to analyze the sources and risk assessment methods of oligomers in food contact materials systematically. The steps and methods of risk assessment of oligomers were introduced， using 1，2，3，4-tetrahydronaphthalene-2，6-dicarboxylic acid， dimethyl ester and Cyclo-di-BADGE as case studies， so as to provide methodological support for the risk assessment and risk management of oligomers in food contact materials in China.

CO2 emissions from heavy-duty vehicles are an important source of greenhouse gases in the transportation sector. However, there is a lack of in-depth research on the characteristics of CO2 emission factors of multiple types of heavy-duty vehicles. The paper conducts a study on the characteristics of carbon dioxide emission factors of multi-type heavy-duty vehicles, with a focus on tractors, heavy-duty trucks, and dump trucks. A method based on C-WTVC for VSP-Bin interval division is proposed to establish a unified bin interval for heavy-duty vehicles, and calculate the CO2 emission factors of different types of heavy-duty vehicles. The study indicates that the carbon dioxide emission factors of tractors are mainly distributed in suburb and highway intervals. The carbon dioxide emission factors of heavy-duty trucks are distributed across three intervals. The CO2 emission factors of dump trucks are concentrated in suburb intervals.

The emission factors of greenhouse gases from motor vehicles are of significant importance for low-carbon and environmentally friendly initiatives. This paper focuses on greenhouse gas emission factors of heavy-duty vehicles. The multi-dimensional Bin interval mode are proposed, which considers multiple parameters such as vehicle speed, acceleration, torque, and rotational speed. Based on this, the emission characteristics of greenhouse gases from heavy-duty vehicles. are investigated under different parameter conditions. The results indicate that as the VSPA value or the engine torque increases, the CO2 emission factor also increases accordingly. The CO2 emission factor is lower at medium to high rotational speeds, while it tends to increase at low rotational speeds. The research findings provide support for monitoring and evaluating greenhouse gas emissions and offer scientific guidance for formulating specific carbon reduction policies, emission targets, and plans.

This paper proposes a multi-scale emission factor dataset constructing method. Firstly, actual road driving and pollutant emission data of heavy-duty trucks are obtained. Subsequently, a method for dividing multi-scale Bin intervals based on engine load, vehicle speed, and acceleration is proposed to establish suitable multi-scale Bin intervals for the driving characteristics of heavy-duty trucks. Finally, based on the proposed method, an emission factor dataset highlighting typical driving characteristics of heavy-duty trucks is constructed. The research findings will provide government regulatory authorities with more microscopic and multi-scale guidance on motor vehicle emissions.

ObjectiveTo infer the relationship between bisphenol A （BPA） exposure and adverse health effects in humans， the human epidemiological data of BPA was evaluated by the weight of evidence approach.MethodsBased on the weight of evidence approach， the human epidemiological research articles on BPA published between 2013 and 2020 were systematically searched， screened and classified. The selected articles were evaluated following the guidelines of evaluating the relevance and reliability of toxicological data developed by the China National Center for Food Safety Risk Assessment. The hazard assessment was performed based on different endpoints.ResultsA total of 188 papers were obtained screening from 134 897 records， of which 68 papers were evaluated as “A/B” or “B” in terms of relevance， and the rest were evaluated as “C”. Only the studies with the relevance evaluation grade of “A/B” or “B” were evaluated for reliability， of which 6 studies were evaluated as “high” reliability and 62 studies were evaluated as “medium” reliability. The endpoints of toxicological effects should include metabolic， reproductive and developmental， neurological， immunological and cardiovascular effects. However， the effect indicators across studies lacked consistency due to study population， exposure duration and indicator design.ConclusionBased on the available evidence of human epidemiological data， the relationship between BPA exposure and adverse health effects in humans is not yet clear.

ObjectiveTo support the probabilistic assessment of food contact materials with consumption parameters and methodology， the establishment of consumption data based on food contact area with different types of alcoholic beverages and different food contact materials was studied.MethodsBased on probability distribution， food contact surface area/volume ratio （S/V） data and alcoholic beverages consumption data were regarded as two independent distribution populations. Monte Carlo simulation was used to calculate the distribution of the food contact area based on consumption data. One thousand rounds of random sampling were conducted in the two populations to quantify the uncertainty.ResultsCategorized by alcoholic beverages-food contact material， beer-glass had the highest average food contact area based on consumption， with an average of 5.500 dm2/d and a 95%CI of 5.302-5.705 dm2/d. Categorized by food contact material， alcoholic beverages with aluminum coating had the highest average food contact area based on consumption， with an average of 5.213 dm2/d and a 95%CI of 4.929-5.532 dm2/d.ConclusionThe food contact area based on consumption data of alcoholic beverages can be the basic parameter for the probabilistic assessment of food contact materials of alcoholic beverages in China， which can be used for the accurate dietary exposure assessment.

ObjectiveTo study the use of packaging materials for tea in China and establish the database of surface area to volume ratios （S/V） of different food contact materials for different types of tea.MethodsSeven categories and 413 tea samples with different packaging forms were purchased from markets and online stores. Food contact surface area of each sample was determined by direct measurement or via 3D surface area measuring instruments. The S/V was calculated based on the food contact surface area and the quality or specification data of the tea products.ResultsAll the contact materials for tea were made of a single material， and the mean S/V was 93.0 dm2/kg， ranging from 3.5 to 595.6 dm2/kg. 99.8% （412/413） of the S/V was equal or higher than 6.0 dm2/kg， and 87.2% （360/413） was in the range of 6.0-200.0 dm2/kg.ConclusionThe S/V of most commercially available tea products in China was higher than 6.0 dm2/kg， a parameter used for risk assessment by European Food Safety Authority （EFSA）. Therefore， using the S/V constructed by this investigation can decrease the uncertainty in the food contact material risk assessment.

ObjectiveTo study the contamination level of mineral oil hydrocarbons in complementary foods for infants and young children and assess its potential health impact for consumers aged 0­3 years old in China.MethodsThe contents of mineral oil saturated hydrocarbons （MOSH） and mineral oil aromatic hydrocarbons （MOAH） were determined by on­line high­performance liquid chromatography coupled with gas chromatography and flame ionization detector. Based on the food consumption data of Chinese residents in 2015， the exposure to mineral oil hydrocarbons in complementary foods of Chinese infants and young children aged 0­3 years old was assessed by simple distribution method.ResultsThe overall detection rate of MOSH （C16-C35） in 4 types of complementary foods （canned foods， rice flour， noodles， and biscuits or molar sticks） in total of 138 commercially available complementary food samples was 45.65%， and the mean contamination level in different types of complementary foods was in the range of 0.55-4.40 mg/kg. The MOAH was only detected in 1 sample of noodles and 4 samples of biscuits or molar sticks. The overall detection rate of MOAH was 3.62%. The average daily exposure and high food consumption （P95） daily exposure of MOSH （C16­C35） for complementary foods consumer only population were 6.21 and 19.27 μg/kg·BW， respectively. The margins of exposure of all age groups were higher than 100.ConclusionThe health risk from dietary exposure to MOSH by consuming complementary foods is very low for infants and young children aged 0­3 years old in China. Attention should be paid to the contamination of MOAH in complementary foods for infants and young children.

The large increase in the on-road vehicle population in China has raised sustainability concerns regarding air pollution prevention, energy conservation, and climate change mitigation. Vehicle emission inventory is an irreplaceable tool to characterize the temporal and spatial distribution of the air pollutant and provide guidance to the policy makers with effective vehicle emission controls. This review paper reviewed two kinds of typical vehicle emission inventories. The top-down vehicle emission inventories is calculated based on the static datasets (e.g., vehicle population, vehicle kilometer traveled, and fuel consumption). These inventories could track historical emissions abatement progress and examine potential benefits from future regulations. The technological evolution in intelligent transportation systems have facilitated emission inventories to satisfy the increasing sophisticated management demand. The bottom-up link-level vehicle emission inventories are development based on the availability of the real-world traffic profiles. To simulate the temporal and spatial patterns with high-resolution, traffic demand model and machine learning methods are employed to elucidate traffic emissions.

Transportation is one of the important fields of carbon emission. Promoting the Carbon Peak in transportation industry is a key point to accelerate the green and low-carbon transformation and promote the high-quality development of the transportation industry. The transportation sector covers a wide range of fields, and there are many coordination departments. The local transportation authorities still lack a strong grasp in carrying out the Carbon Peak work. It is urgent to further improve the Carbon Peak system and mechanism in the transportation sector. This paper refines the current situation and characteristics of carbon emission in the transportation field of Inner Mongolia Autonomous Region, summarizes the progress of Carbon Peak in the transportation field, analyzes the constraints of the system and mechanism of Carbon Peak in the transportation field, and puts forward suggestions to further improve the system and mechanism of carbon emission reduction in the transportation field of Inner Mongolia Autonomous Region.

Due to the lack of air and traffic monitoring data in China, this study employed a remote sensing (RS) system and air quality monitoring sensors to investigate the air pollutant concentrations, traffic profiles and meteorological data in order to characterize roadside pollutant concentrations and identify their influence factors for a major road in Lanzhou. The results suggested that the temporal variations of concentrations of SO2, NO2, PM2.5, PM10 and CO peaked at 5:00-7:00 while O3 peaked at 17:00. The concentrations of roadside air pollutants were lower on weekdays than weekends except O3. The concentrations of PM2.5 and PM10 declined with the height of the monitoring sites increased, peaking at 2-meter height whereas SO2, NO2, CO, and O3 reached their highest concentrations at 4-meter height. The concentrations of roadside NO2 and CO show positive correlations with the volume of heavy-duty trucks (HDTs) and light-duty passenger vehicles (LDPVs), respectively. This study provided scientific support to the establishment of roadside air quality monitoring systems and the assessment of the environmental and health impact from vehicle emissions.

CFD, comprising multiple types of softwares, involves complex technological theories and is used to solve profound issues with a huge amount of calculation. Given the complexity and profundity, this study selects Fluent, OpenFOAM and Star-CCM+ as representatives to review the application of the CFD simulation technology in the vehicle exhaust dispersion models. Fluent, a commercial CFD software, started relatively early and has so far been the most widely used in the field of motor vehicle exhaust dispersion research; OpenFOAM, is open source and has a large number of models and algorithms. Apart from supporting pure model research, OpenFOAM has broad application prospects in coupling with the mesoscale model WRF to improve the accuracy of pollutant dispersion simulation; Star-CCM+, less applied in the research field of vehicle exhaust dispersion, focuses more on vehicle air conditioning system, vehicle radiator, refueling, vehicle aerodynamic noise source simulation and other related fields. The research provides theoretical basis and scientific reference for the application of CFD in the field of urban block-scale air quality research. In the future, with the rapid development of computer technology and the introduction of new theories and intelligent algorithms, CFD technology is very likely to achieve new breakthroughs and continue to enjoy even wider application in the research of motor vehicle exhaust dispersion.

Novel synthesis methods are urgently expected for visible‐light‐driven photocatalysts. Hereby we report a series of TiO2‐based photocatalysts (T‐x) by using a simple pot‐in‐pot reaction approach. In this approach, two reaction media are isolated from each other by the crucible reactor. The obtained T‐x sample shows nanosheet‐aggregate structure and wide visible‐light absorption property with an optimal bandgap of 2.35 eV. Factors that influence the bandgap modulation, including nitrogen, fluorine, carbon and oxygen vacancy etc. are discussed in detail. Characterization results demonstrate a substantial increase of oxygen vacancies and carbon atoms in T‐x sample, which were proven to the main reason for the extended visible‐light absorption and enhanced photocatalytic performance. Under visible‐light irradiation, T‐x sample shows excellent photocatalytic degradation activity for RhB with a k value of 0.027 min−1 and good photoelectrochemical performance. Trapping experiments reveal that ⋅OH are the main active species to oxidize the RhB dye. This new pot‐in‐pot reaction approach enables synthesis of novel photocatalytic materials with wide visible‐light‐response. [ABSTRACT FROM AUTHOR]