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Liquid crystal monomers (LCMs), identified as emerging contaminations, have been detected in soils and plants, but their accumulation characteristics in plants haven't been studied. Therefore, this study systematically investigated the accumulation characteristics of LCMs in plants from four dimensions (i.e., plant fruit species, soil types, plant growth stages, and LCMs categories) for the first time. The LCMs concentrations (9.96 × 10−4 to 114.608 ng/g) in 22 plant fruits were predicted by the partition-limited model. Grains with the highest lipid content showed the highest LCMs accumulation propensity. Plants grown in paddy soil showed a strong LCMs accumulation capacity. Results showed that the LCMs accumulation capacity in plants from soils decreased when the soil organic matter content increased. A preferential accumulation of LCMs in plant root systems during growth was found by the molecular dynamics simulations. Compared to polychlorinated biphenyls (as the reference contaminants of LCMs), LCMs exhibit higher accumulation in plant roots and lower translocation to shoots. For the fourth dimension, lipophilicity was found to be the main reason of LCMs accumulation by intergraded stepwise linear regression with sensitivity analysis. This is the inaugural research concentrating on LCMs accumulation in plants, providing insights and theoretical guidance for future LCMs management strategies multidimensionally. Liquid crystal monomers (LCMs) are one of the essential materials for liquid crystal displays and have been identified as emerging containments, with detections now confirmed in soils and plants. However, the mechanism of their bioaccumulation in plants has not been established. Consequently, this paper presents the first comprehensive study on LCMs accumulation mechanisms in plants, identifying the patterns of LCMs accumulation in plants from various dimensions such as different plant species, soil types, plant growth stages, and LCMs categories, enhancing the understanding of the environmental behavior of LCMs and providing a theoretical reference for the formulation of LCMs management strategies. [Display omitted] • The first study focuses on the accumulation characteristics of LCMs in plants. • Plants with higher lipid contents may lead to higher accumulation of LCMs. • The higher the SOM content in the soil, the lower the LCMs uptake rate by plants. • LCMs exhibit a higher accumulation propensity in plant roots than that in shoots. • LCMs' lipophilicity contributes the most to the accumulation capacity in plants. [ABSTRACT FROM AUTHOR]

Liquid crystal monomers (LCMs), one of the key materials for liquid crystal displays, have been considered as emerging pollutants in recent years. However, the environmental behaviors of LCMs have not yet been well investigated. The toxicity data of 1173 LCMs were calculated by integrated computational simulation methods in this study. It showed that 64.6% LCMs exhibited PBT (persistent, bioaccumulative, and toxic) properties. Based on the results, 1173 LCMs were identified as molecules possessing the highest level of acute toxicity to aquatic organisms. Among which, and a human health risk priority control list about LCMs was generated in this study, among which 435 were classified as requiring priority control LCMs. It was confirmed that LCMs could eventually accumulate in the human body along the aquatic food chain or penetrate the bloodstream through the dermis, thereby causing harm to health by identifying the exposure pathways of LCMs in humans. Additionally, the electronegativity of the side chain group of LCMs is the main factor causing toxicity differences; therefore, the LCMs containing halogens presented significant acute and chronic toxic effects. This study provided a more comprehensive understanding of LCMs for the public and scientific strategies for controlling LCMs. [Display omitted] • The environmental behaviors of 1173 LCMs reported in the literature were identified. • All LCMs exhibited the highest level of acute toxicity, especially for crustaceans. • LCMs can bind to various receptors, 435 LCMs pose significant risks to human health. • LCMs accumulate in human bodies through biomagnification and dermal permeation. • The electronegativity of the side chain group of LCMs leads to toxicity differences. [ABSTRACT FROM AUTHOR]

It is essential to understand the atmospheric fate of liquid crystal monomers (LCMs), an important component in liquid crystal displays (LCDs); however, limited information is available at present. In this study, the atmospheric reaction mechanism, kinetics and toxicity evolution of three fluorinated biphenylethyne LCMs (1,2,3−trifluoro−5−(2−(4−methylphenyl)ethynyl)benzene (m−TEB), 1,2,3−trifluoro−5−(2−(4−ethylphenyl)ethynyl)benzene (e−TEB), 1,2,3−trifluoro−5−(2−(4−propylphenyl)ethynyl)benzene (p−TEB)) are investigated by theoretical calculations. Results show that the initial reactions of·OH addition to −C ≡ C− groups and hydrogen abstraction from alkyl groups (−CH 3 , −C 2 H 5 , −C 3 H 7) are dominant pathways. The resulting transformation products (TPs) for m-TEB are mainly highly oxidized multi-functional compounds such as benzil-based compounds, benzoic acid, alcohols, aldehydes, diketone and epoxy compounds. Results also show that some TPs exhibit higher aquatic toxicity than the parent. The calculated rate constants of m−TEB, e−TEB and p−TEB with·OH at 298 K are in the ranges of (1.3 −8.6) × 10−12 cm3 molecule−1 s−1, and the corresponding atmospheric half-lives are 3.8−9.3, 2.2−5.4 and 0.6−1.4 days, respectively. This evidences that m−TEB and e−TEB may have atmospheric persistence and could undergo long-range transport. The results herein could be helpful for clarifying the atmospheric fates, persistence and risks of fluorinated LCMs with ethynyl benzene center. [Display omitted] • The reaction kinetics and mechanism of three LCMs initiated by·OH is investigated. • ·OH addition to alkynyl and H-abstraction from alkyl groups are dominant pathways. • m−TEB and e−TEB with atmospheric half-lives > 2 days can persist in the atmosphere. • The major degradation products are a range of oxidized multi-functional compounds. • Some transformation products show enhanced toxicity compared with the parent LCM. [ABSTRACT FROM AUTHOR]

• Microwave-assisted hydrothermal method can effective decompose liquid crystal. • The decomposition rate of liquid crystal reaches 100 % under the optimized condition. • Reaction kinetic analysis of liquid crystal under optimized conditions is studied. • Two possible decomposition processes of liquid crystal are proposed. • The liquid crystal mixture is treated sufficiently into non-hazardous products. Liquid crystal (LC), as a crucial component of liquid crystal display (LCD), improperly treatment of which will possibly impair ecosystems and human health. In view of the advantages of hydrothermal reaction and microwave irradiation, this paper intensively studied the process of microwave-assisted hydrothermal (MWAH) decomposition of LC wastes. The experimental materials include a kind of refractory fluorinated liquid crystal commonly used in thin-film transistor LCD, and its mixture with the other two typical liquid crystal monomers in the waste low-end display panels. Under the MWAH process, the optimized condition for thorough decomposition of 0.67 g.L−1 fluorinated liquid crystal is 0.653 mol.L−1 H 2 O 2 , 1 g.L−1 AC, 300 mL water, 250 °C and 7 min. The superiority of microwave in enhancing hydrothermal treatment efficiency was verified by the first-order kinetic reaction equation fitted for the decomposition process under optimal condition, along with two possible decomposition pathways tentatively proposed after characterizing the intermediate products. Under the same condition, 1 g.L−1 mixture of fluorinated liquid crystal and the other two liquid crystal monomers were entirely decomposed with no harmful byproduct detected, suggesting that microwave irradiation could effectively promote the hydrothermal decomposition of liquid crystal wastes. [ABSTRACT FROM AUTHOR]