Liquid crystal monomers (LCMs) in liquid crystal displays (LCDs) may be released into the environment, especially in electronic waste (e-waste) recycling industrial parks with a high pollution risk. However, little has been known about the environmental release and human exposure to LCMs until now. Herein, a total of 45 LCMs were detected in LCDs of commonly used smartphones and computers by high-resolution mass spectrometry with suspect screening analysis. Fluorinated biphenyls and their analogs were the dominant LCMs. Based on available standards of the screening results and previous studies, 55 LCMs were quantified in samples from an e-waste recycling industrial park in Central China. The LCMs were frequently detected in outdoor dust (n = 43), workshop #1 indoor dust (n = 53), and hand (n = 43) and forehead wipes (n = 43), with median concentrations of 6950 ng/g, 67,400 ng/g, 46,100 ng/m2, and 62,100 ng/m2, respectively. The median estimated daily intake values of the LCMs via dust ingestion and dermal absorption were 48.3 and 16.5 ng/kg body weight/day, respectively, indicating a high occupational exposure risk of these compounds. In addition, 16 LCMs were detected in the serum of eight elderly people (≥60 years old) with over 5 years of experience in e-waste dismantling operations, resulting in a total concentration range of 3.9–26.3 ng/mL.

Highly ordered mesoporous materials with extremely high hydrothermal stability have been successfully synthesized by a novel and facile approach. Our method is built on the understanding that the hydrothermal treatment process plays an important role in the synthesis of mesoporous materials. It is proposed that in order to use high temperature hydrothermal treatment to increase the inorganic framework cross-linkage, an important requirement is that the organic surfactants must be retained as much as possible to maintain the preformed organic−inorganic composite mesostructure against framework shrinkage during the hydrothermal treatment process. This requirement can be achieved by enhancing the surfactant−silanol interaction at the organic−inorganic interface through adjusting the hydrothermal treatment pH and adding acetic acid (HAc) during the synthesis. When a high temperature (∼200 °C) hydrothermal treatment is employed, ordered mesoporous materials can only be obtained in a hydrothermal treatment pH range of 1−3. When the hydrothermal treatment pH is near the isoelectric point of silica, the highest silanol density on silica walls can entrap the largest amount of surfactants within pores, resulting in highly ordered mesostructured materials. Moreover, the disadvantage of the hydrothermal treatment under strong acidic conditions widely adopted in the literature has been revealed. Compared to previous reports, our approach is simple and does not involve environmentally unfriendly or expensive agents, thus is easy to be scaled up for industrial applications. Most strikingly, the highly ordered mesostructure of aluminosilicate synthesized by our approach can be maintained after steam treatment at 800 °C for 5 h with only a 4.9% decrease in the Brunauer−Emmett−Teller surface area. Our achievements have added new contributions to understanding the preparation of highly ordered and highly stable mesoporous materials, which sheds light on the practical applications of this new family of porous materials in the petroleum and petrochemical industry.

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A large-scale survey was conducted by measuring five organophosphite antioxidants (OPAs) and three novel organophosphate esters (NOPEs) in 139 dust samples across China. The median summed concentrations of OPAs and NOPEs in outdoor dust were 33.8 ng/g (range: 0.12−53,400 ng/g) and 7990 ng/g (2390−27,600 ng/g), respectively. The dust concentrations of OPAs associated with the increasing economic development and population density from western to eastern China, whereas the NOPE concentration in Northeast China (median, 11,900 ng/g; range, 4360−16,400 ng/g) was the highest. Geographically, the distribution of NOPEs was significantly associated with annual sunshine duration and precipitation at each sampling site. Results of laboratory experiments further revealed that the simulated sunlight irradiation promoted the heterogeneous phototransformation of OPAs in dust, and this process was accelerated with the existence of reactive oxygen species and enhanced relative humidity. Importantly, during this phototransformation, the hydroxylated, hydrolyzed, dealkylated, and methylated products, e.g., bis(2,4-di-tert-butylphenyl) methyl phosphate, were identified by nontargeted analysis, part of which were estimated to be more toxic than their parent compounds. The heterogeneous phototransformation pathway of OPAs was suggested accordingly. For the first time, the large-scale distribution of OPAs and NOPEs and the phototransformation of these "new chemicals" in dust were revealed.

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The absorption, translocation, and biotransformation behaviors of organophosphate esters (OPEs) and diesters (OPdEs) in a hydroponic system were investigated. The lateral root was found as the main accumulation and biotransformation place of OPEs and OPdEs in lettuce. The nontarget analysis using high-resolution mass spectrometry revealed five hydroxylated metabolites and five conjugating metabolites in the OPE exposure group, among which methylation, acetylation, and palmitoyl conjugating OPEs were reported as metabolites for the first time. Particularly, methylation on phosphate can be a significant process for plant metabolism, and methyl diphenyl phosphate (MDPP) accounted for the majority of metabolites. The translocation factor values of most identified OPE metabolites are negatively associated with their predicted logarithmic octanol–water partitioning coefficient (log K ow) values (0.75–2.45), indicating that hydrophilicity is a dominant factor in the translocation of OPE metabolites in lettuce. In contrast, palmitoyl conjugation may lead to an enhanced acropetal translocation and those with log K ow values < 0 may have limited translocation potential. Additionally, OPE diesters produced from the biotransformation of OPEs in lettuce showed a higher acropetal translocation potential than those exposed directly. These results further emphasize the necessity to consider biotransformation as an utmost important factor in the accumulation and acropetal translocation potential of OPEs in plants.

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