Background Occupational health places often involve complex dust samples characterized by diverse compositions and a lack of prior supplementary information. These factors pose challengs in ascertaining crystal phase composition, creating a hurdle for both crystallographic screening and subsequent precise quantification. Hence, establishing a systematic, non-targeted crystal phase screening strategy is essential for analyzing complex occupational dust samples lacking background data. Objective To develop a non-targeted crystal phase screening strategy and a corresponding evaluation mechanism for complex occupational dust, by leveraging various non-destructive spectroscopy techniques and automated full-spectrum fitting, aiming to establish a technical foundation for phases identification and standardless quantification in samples with unknown backgrounds. Methods An extensible and non-targeted screening strategy and a dual-verification mechanism were formulated specifically for occupational health samples. The approach integrated energy dispersive X-ray fluorescence spectroscopy (EDXRF), Fourier-transform infrared (FTIR), and Raman spectroscopy to ensure accurate phase identification. To demonstrate applicability, a representative routine monitoring sample was analyzed. The strategy was validated based on the precision of Rietveld refinement results and the logical consistency of phase distribution within specific occupational settings. Furthermore, universality was tested across multiple industrial sectors prone to silica-related dust, including refractory material manufacturing, construction stone processing, and steel rolling. Results Utilizing high-precision X-ray diffraction (XRD) data from a representative complex dust sample, a comprehensive workflow comprising primary component identification, sequential phase screening, and gap-filling analysis successfully identified 13 highly correlated crystal phases, 11 of which exhibited strong industry relevance. Subsequent to these screening results, Rietveld full-spectrum fitting yielded a calculated pattern closely matching the experimental data, with a relatively flat residual line and high statistical reliability (R_wp=5.121%, R_exp=2.955%, and χ²=1.733). In universality tests across various industrial sites, all samples achieved R_wp < 20% and χ² <2. In addition, the quantitative phase distributions remained self-consistent and highly aligned with actual industrial processes and material positioning. Conclusion A crystal phase screening strategy combining multi-modal spectroscopic analysis with computer-aided full-spectrum fitting is successfully established. This method effectively identifies multiple crystalline substances in uninformed samples and achieves non-targeted screening of complex occupational dust samples. Validated through both numerical accuracy and phase distribution, the strategy provides a practical and robust methodological framework for analyzing complex occupational dust samples without background information.

Background Nitrosamines (NAms), emerging as disinfection by-products in drinking water, are highly carcinogenic. Given the significant NAms contamination reported in various regions of China, evaluating the contamination levels and health risks of NAms in terminal direct drinking water is of great urgency. Objective To investigate the concentration levels of NAms in piped direct drinking water at primary and secondary schools in Shanghai, and to assess the potential health risks posed to different age groups through this exposure pathway. Methods A total of 198 water samples were collected from 66 primary and secondary schools across five districts in Shanghai from May to June 2023. The mass concentrations of eight major NAms were quantified using solid-phase extraction coupled with gas chromatography-mass spectrometry (GC-MS). A carcinogenic health risk model was employed to evaluate the lifetime cancer risks associated with NAms exposure via direct drinking water for various age groups. Results Among the 198 samples, NAms were detected in 196 samples, with concentrationsranging from below the limit of detection (LOD) to 106.06 ng·L⁻¹. The average concentration of total NAms was 21.30 ng·L⁻¹, with N-nitrosodimethylamine (NDMA) exhibiting the highest detection rate at 98.5%. Significant differences in NAms concentrations were observed among water treatment systems utilizing ultrafiltration (UF), nanofiltration (NF), and reverse osmosis (RO) as core processes (P<0.05). The lifetime cancer risks for different age groups ranged from 1.38×10⁻⁶ to 1.11×10⁻⁵, with NDMA contributing the most to the overall risk (82.1%). The carcinogenic risk for adults (1.08×10⁻⁵) was higher than that for children and adolescents (1.38×10⁻⁶ to 2.61×10⁻⁶). Among children and adolescents under 18 years of age, the risk decreased as age increased. Conclusion Trace levels of NAms, primarily NDMA, are detected in the piped direct drinking water at primary and secondary schools in Shanghai, with concentrations vary significantly depending on the water treatment process. The carcinogenic risks of NAms exposure via direct drinking water for all age groups are below the acceptable level (1×10⁻⁴) recommended by the U.S. Environmental Protection Agency (EPA).

Background Benzothiazoles and benzotriazoles are ubiquitously detected in drinking water, posing potential health risks. Developing a reliable and sensitive analytical method is critical for assessing their exposure levels and associated risks. Objective To establish an automated solid-phase extraction (SPE) coupled with liquid chromatography-tandem mass spectrometry method for the simultaneous determination of benzothiazole, 2-aminobenzothiazole, benzotriazole, and 5-chlorobenzotriazole in drinking water. Methods Key parameters were systematically optimized. Three mobile phase systems were compared to evaluate their effects on chromatographic peak shape and separation; three SPE cartridges were tested for extraction efficiency; the influences of water pH on extraction recoveries and matrix effects were investigated; the contributions of pretreatment steps to benzothiazole blank were analyzed, and control measures were established; nitrogen evaporation temperatures were tested to ensure analyte stability. The optimized parameters were used to develop the method, validate its performance, and analyze drinking water samples. Results Drinking water samples were first adjusted to pH 6.0 with formic acid, and then extracted using HLB cartridges. After elution with 6 mL methanol, the eluate was concentrated under nitrogen evaporation at 45 °C, followed by separation on a C18 column using a gradient elution of acetonitrile-0.1% formic acid solution, and tandem mass spectrometry detection. Avoiding nitrogen blow-drying during SPE and eliminating the use of polypropylene materials during nitrogen evaporation can effectively minimize benzothiazole contamination. Good calibration linearity was obtained for the target analytes in the concentration range of 5.0-250 μg·L⁻¹, with a correlation coefficient of r > 0.995. The method detection limits were in the range of 1.0-5.0 ng·L⁻¹. The recoveries of the target analytes in pure water and tap water were 80.2%-119.5% and 72.2%-115.6%, respectively, with relative standard deviations of were 3.2%-12.8% and 2.3%-11.6%, respectively. When applying this method to actual water samples, benzotriazole was detected in 100% of treated and tap water samples, with median concentrations of 79.4 ng·L⁻¹ and 114 ng·L⁻¹, respectively. Benzothiazole was detected in 83.3% of treated water samples and 100% of tap water samples, with median concentrations of 48.3 ng·L⁻¹ and 65.4 ng·L⁻¹, respectively. In addition, 5-chloro-benzotriazole exhibited low detection rates and concentrations, while 2-amino-benzothiazole was undetected. Conclusion The developed method demonstrates high accuracy, reliability, and sensitivity, making it suitable for the analysis of trace levels of benzothiazoles and benzotriazoles in drinking water.

Background Nitrosamines (NAms), emerging as disinfection by-products in drinking water, are highly carcinogenic. Given the significant NAms contamination reported in various regions of China, evaluating the contamination levels and health risks of NAms in terminal direct drinking water is of great urgency. Objective To investigate the concentration levels of NAms in piped direct drinking water at primary and secondary schools in Shanghai, and to assess the potential health risks posed to different age groups through this exposure pathway. Methods A total of 198 water samples were collected from 66 primary and secondary schools across five districts in Shanghai from May to June 2023. The mass concentrations of eight major NAms were quantified using solid-phase extraction coupled with gas chromatography-mass spectrometry (GC-MS). A carcinogenic health risk model was employed to evaluate the lifetime cancer risks associated with NAms exposure via direct drinking water for various age groups. Results Among the 198 samples, NAms were detected in 196 samples, with concentrationsranging from below the limit of detection (LOD) to 106.06 ng·L⁻¹. The average concentration of total NAms was 21.30 ng·L⁻¹, with N-nitrosodimethylamine (NDMA) exhibiting the highest detection rate at 98.5%. Significant differences in NAms concentrations were observed among water treatment systems utilizing ultrafiltration (UF), nanofiltration (NF), and reverse osmosis (RO) as core processes (P<0.05). The lifetime cancer risks for different age groups ranged from 1.38×10⁻⁶ to 1.11×10⁻⁵, with NDMA contributing the most to the overall risk (82.1%). The carcinogenic risk for adults (1.08×10⁻⁵) was higher than that for children and adolescents (1.38×10⁻⁶ to 2.61×10⁻⁶). Among children and adolescents under 18 years of age, the risk decreased as age increased. Conclusion Trace levels of NAms, primarily NDMA, are detected in the piped direct drinking water at primary and secondary schools in Shanghai, with concentrations vary significantly depending on the water treatment process. The carcinogenic risks of NAms exposure via direct drinking water for all age groups are below the acceptable level (1×10⁻⁴) recommended by the U.S. Environmental Protection Agency (EPA).

ObjectiveTo investigate the chemical hazards in the production line of lithium batteries, so as to provide a scientific basis for the management of occupational-health risk and to promote the healthy and sustainable development of the lithium battery industry. MethodsAn on-site survey on the process flow of the production of lithium battery was conducted in an enterprise. Volatile organic compounds (VOCs) in the occupational environment were collected by Summa canisters, carbonates and N-methyl pyrrolidone (NMP) were collected using activated carbon tubes, and airborne metals were collected using filter membranes. VOCs, carbonates and NMP were detected by gas chromatography-mass spectrometry (GC-MS), and airborne metal elements in the dust samples were analyzed by inductively coupled plasma mass spectrometry (ICP-MS). ResultsNon-targeted environmental monitoring results indicated that NMP was detected in the negative /positive electrode coating, assembly and drying filling workstations, dimethyl carbonate (DMC) was detected in the assembly, drying and electrolyte injection workstations, and ethyl methyl carbonate (EMC) was detected solely in the electrolyte injection workstation. Semi-quantitative analyses of VOCs identified 136 pollutants, including acrylonitrile and halohydrocarbons. Quantitative targeted environmental monitoring results revealed the highest geometric mean (GM) concentration of EMC (31.450 mg·m^-3) was found in the assembly and drying workstations, diethyl carbonate (DEC) was detected in all workstations. While vinylene carbonate (VC) and ethylene carbonate (EC) were detected only in electrolyte injection, assembly and drying workstations. NMP was detected in all positive electrode coating samples, with a GM concentration of 5.68 mg·m^-3 (concentration range: 4.0‒ 7.4 mg·m^-³). Lithium was exclusively detected in dust samples from the liquid injection workstation (GM: 0.014 μg·m^-³). ConclusionNMP, EMC, DEC, and other chemicals are identified at the key workstations such as the positive electrode coating, electrolyte injection, assembly and drying in the lithium production line. Furthermore, semi-quantitative VOCs analyses identified 136 pollutants, demonstrating a characteristic of multicomponent chemical exposure.

Background Bisphenol compounds are non-persistent environmental endocrine disruptors and frequently detected in drinking water systems, indicating potential human health risks through drinking water. Objective To establish and optimize a simultaneous determination method for 16 BPs in drinking water by online solid-phase extraction-ultra high-performance liquid chromatography-triple quadrupole mass spectrometry, in order to efficiently monitoring BPs in drinking water. Methods Candidate online solid-phase extraction conditions, chromatographic columns, mobile phase systems, mass spectrometry parameters, and other conditions were compared by chromatographic peaks of BPs, and processing conditions such as water sample preservation and pretreatment were optimized. The pH level of drinking water samples was adjusted and solid particles were removed. After extraction and purification by an online solid-phase extraction system, samples were detected by ultra-high performance liquid chromatography tandem mass spectrometry and quantified by isotope internal standard method. The proposed method was verified by pure water and terminal tap water, and evaluated by spiked recovery rate and relative standard deviation. Eighty-eight tap water samples from different regions of local pipeline network were collected for method application. Results For the 16 BPs, the calibration curves showed good linearity between 1.0 and 75 ng·L⁻¹ and the correlation coefficients were greater than 0.995. The detection limit of the method was less than 0.30 ng·L⁻¹, and the quantification limit of the method was less than 1.0 ng·L⁻¹. When the spiked concentrations for the 16 BPs were 5.0, 15, and 40 ng·L⁻¹, the average spiked recovery rates of the test substances were between (100 ± 10)%, and the relative standard deviations were all below 10%. In the method application to the local terminal water samples, the positive rates of bisphenol S (BPS), bisphenol A (BPA), and bisphenol AF (BPAF) were as high as 93.2%, 77.3%, and 29.5%, respectively. The concentrations of BPS were from not detected (N.D.) to 37.8 ng·L⁻¹, and the concentrations of BPA were from N.D. to 52.0 ng·L⁻¹. Conclusion The method using an online solid-phase extraction system is established, featuring simple pre-treatment, small sample volume, high degree of automation, low detection limit, and good accuracy and precision. This method can be applied to the quantitative monitoring of 16 BPs at ng·L⁻¹ level in drinking water.

Background Workers in printing jobs are exposed to a variety of organic solvents at low levels for a long period of time. Previous studies have focused on the main components in Material Safety Data Sheet or high-risk occupational hazardous agents, but have not been able to comprehensively and accurately identify the volatile organic compounds (VOCs) in printing jobs. Objective To qualitatively analyze the VOCs in ink, detergent, varnish, fountain solution, and other raw and auxiliary materials by headspace gas chromatography-mass spectrometry, and to accurately identify the occupational hazardous agents in printing jobs. Methods Raw and auxiliary materials used in printing jobs in 6 printing enterprises in Shanghai were sampled by headspace sampling, analyzed by gas chromatography-mass spectrometry, identified by National Institute of Standards & Technology ( NIST) Standard Library and retention time, and quantified by peak area percentage. Results A total of 181 VOCs were reported in the headspace of 25 organic solvent samples, with a total detection frequency of 337 items and 13.2±12.3 VOCs per sample. The most frequently detected VOCs category was naphthene, with a total of 69 items detected (22.5%), dominated by cyclohexane. The characteristics of VOCs components in the headspace of different types of samples were different. The largest number of VOCs was detected in the headspace of detergent samples, with an average of 31.5 VOCs detected. The characteristic components in detergent were aromatic hydrocarbons and ester compounds; alcohols were the characteristic components in varnish; and ester compounds were the characteristic components in ink. The results of cluster analysis showed that ethanol, toluene, ethyl acetate, cyclohexane, and acetone were occupational hazardous agents with high levels of exposure in printing jobs. Conclusion Many kinds of organic solvents used in printing process are difficult to identify by traditional methods. Headspace gas chromatography-mass spectrometry can help to accurately identify VOCs in the workplace, so as to more accurately assess the occupational hazards, and to provide a technical basis for guiding occupational health monitoring and implementing corresponding occupational health risk management and control.

Background Nitrosamines (NAms) are highly carcinogenic and frequently detected in drinking water systems in China, indicating potential human health risk through drinking water. Objective To analyze the distribution of NAms in drinking water in Shanghai and to evaluate relevant human health risk. Methods A total of 94 samples of source water and 120 samples of finished water were collected in February (dry period) and August (wet period) of 2021 from 30 drinking water plants in Shanghai, and eight NAms were quantitatively analyzed by gas chromatography tandem mass spectrometry after solid phase extraction. Cancer risks for different age groups caused by NAms exposure through water were evaluated using Monte Carlo probabilistic method and carcinogens risk assessment model recommended by the United States Environmental Protection Agency. Results The concentrations of total NAms in source and finished water were 12.56-65.86 ng·L⁻¹ and 8.52-57.38 ng·L⁻¹, respectively. The average concentration of total NAms was higher in source water (33.50 ng·L⁻¹) than in finished water (22.07 ng·L⁻¹, P<0.05) during dry season, and lower in source water (16.90 ng·L⁻¹) than in finished water (21.02 ng·L⁻¹, P<0.05) during wet season. The average concentration of total NAms in source water during dry season was twice of that during wet season. The positive rate of N-nitrosodimethylamine (NDMA) was the highest (100%) among the eight NAms. The cancer risk of exposure to NAms in finished water in Shanghai was mainly from the ingestion route, which was mostly caused by NDMA. The cancer risk from exposure to NAms in water for children (median=4.32×10⁻⁵) was slightly higher than that for adults (median=3.34×10⁻⁵) and adolescents (median=2.27×10⁻⁵). The cancer risks of exposure to NAms in water for people of different ages were mainly (80% - 95%) at an acceptable level (1×10⁻⁶ - 1×10⁻⁴). Conclusion NAms contamination is positive in Shanghai’s drinking water and NDMA is the main contaminant. The removal of NAms in water by current water treatment process is season-dependent. The cancer risk of children exposed to NAms in water was slightly higher than that of adults and adolescents, but all at acceptable levels.

Background Nitrosamines, especially N-nitrosodimethylamine (NDMA), are highly carcinogenic and frequently detected in drinking water systems in China, indicating potential human health risk through drinking water. Objective This study aims to analyze the distribution of NDMA in urban drinking water around China and to evaluate relevant human health risk, thus providing recommendations for drinking water safety standards. Methods The database of China National Knowledge Infrastructure was searched using nitrosamines and drinking water as key words in Chinese, and PubMed was searched usingN-nitrosodimethylamine or nitrosodimethylamine or NDMA, drinking water, and China as key words in English for relevant literature published from January 1, 2000 to March 1, 2021. Eligible data were extracted to statistically analyze the spatiotemporal exposure levels of NDMA in raw and finished water serving Chinese cities. According to the health risk assessment model for carcinogens recommended by the United States Environmental Protection Agency (US EPA), the cancer risk via drinking water of NDMA in finished water was evaluated for different age groups and different regions. Results A total of 102 studies were retrieved, 21 of which met the inclusion criteria and were finally included. The NDMA concentrations in 347 raw water samples and 276 finished water samples were extracted and studied, with positive rates of 82.4% and 67.0%, levels of not detected (ND)-141 and ND-67.1 ng·L⁻¹, and the 95th quantiles of 51.4 and 32.1 ng·L⁻¹, respectively. The level of NDMA in raw water was higher than that in finished water in cities of East and North China (P<0.05). East China had the highest average concentrations of NDMA in raw and finished water (21.4 and 9.0 ng·L⁻¹ respectively). In East China, the average concentrations of NDMA in raw and finished water from 2018 to 2019 (5.9 and 6.1 ng·L⁻¹ respectively) were significantly lower than those from 2015 to 2017 (28.7 and 16.5 ng·L⁻¹ respectively) (P<0.05). The average concentration of NDMA in rivers, lakes, ponds, and streams as drinking water sources (20.8 ng·L⁻¹) was significantly higher than that in groundwater sources (8.0 ng·L⁻¹) and in reservoir sources (6.5 ng·L⁻¹) (P<0.05). The average concentration of NDMA in finished water with pre-chlorination (9.4 ng·L⁻¹) was higher than that without (6.0 ng·L⁻¹) (P<0.05). The cancer risk of NDMA through drinking water for children over 1 year old in China decreased with older age, and the risk of infants aged 1~<2 years (2.52×10⁻⁴) was 23 times higher than that of adults (1.09×10⁻⁵) (P<0.05). Conclusion Raw water pollution is the main source of NDMA in urban drinking water in China, and current water treatment technology can partially remove NDMA. The NDMA level in finished water of East China shows a downward trend in recent two years. The carcinogenic risk of NDMA via drinking water for children is higher than that for adults, and their health risk management needs to be strengthened. The study findings recommend 35 ng·L⁻¹ as the limit of NDMA water quality safety standard in China.