Occurrence of organic ultraviolet absorbers in the particle and gas samples from plastic greenhouses: Human inhalation intake risk assessment.

The environmental pollution of organic ultraviolet absorbers (UVAs) has attracted global attention. However, the distribution, sources and risk assessment of UVAs in air from plastic greenhouses are rarely reported. This study was the first to investigate the concentrations of ten UVAs in the air samples from plastic greenhouses. The total concentrations of ten UVAs (∑10UVAs) in the air samples ranged from 5.7 × 103 ng/m3 to 6.3 × 103 ng/m3 (median 5.7 × 103 ng/m3) in greenhouses covered with biodegradable mulch film, 288.2 ng/m3 to 376.4 ng/m3 (median 333.9 ng/m3) in greenhouses covered with PE mulch film, and 97.9 ng/m3 to 142.6 ng/m3 (median 114.9 ng/m3) in greenhouses covered without mulch film. The concentrations of ten UVAs in 65 commercial agricultural films were simultaneously analyzed. Additionally, the potential health risks for greenhouse workers exposed to UVAs were estimated. And the migration simulations showed that the health risk in greenhouses may be higher even if only one UVA is added to the biodegradable mulch film. Therefore, the exposure risk of UVAs in plastic greenhouses needs to be highly prioritized.

Research progress on GPX4 targeted compounds.

Blocking the System Xc-_ GSH_GPX4 pathway to induce ferroptosis in tumor cells is a novel strategy for cancer treatment. GPX4 serves as the core of the System Xc-/GSH/GPX4 pathway and is a predominant target for inducing ferroptosis in tumor cells. This article summarizes compounds identified in current research that directly target the GPX4 protein, including inhibitors, activators, small molecule degraders, chimeric degraders, and the application of combination therapies with other drugs, aiming to promote further research on the target and related diseases.

Uptake, accumulation and metabolism of UV-320 in vegetables and its impact on growth and quality.

UV-320 is classified as a Substance of Very High Concern (SVHC) by the European Chemicals Agency and has attracted significant attention due to its presence in the environment. Understanding the uptake, translocation and metabolic patterns of UV-320 in vegetables is essential for assessing their ability to bioaccumulate and potential risks to human health. In this study, we investigated the uptake and translocation of UV-320 in lettuce and radish by hydroponic experiments. The results showed that the root concentration factors (Croot/Csolution, RCF) of lettuce and radish were in the range of 47.9 to 464 mL/g and 194 to 787 mL/g, respectively. The transfer factors (Cshoot/Croot, TF) were observed to be 0.001-0.012 for lettuce and 0.02-0.05 for radish. Additionally, non-targeted screening identified twelve phase I and one phase II metabolites of UV-320 in vegetables, which were confirmed based on their molecular formulas and structures. The metabolic pathways involving oxidation, ketonylation and deamination were proposed in vegetables. Also, we have observed that UV-320 inhibits the growth of vegetables. Meanwhile, we evaluated the health risk of UV-320 in lettuce and radish and found that the consumption of lettuce is relatively safe, while the consumption of radish has a risk of HQ >1 for both adults and children, which should be seriously considered. This study provides valuable insights into the behavior and ecological risks of UV-320 in the environment.

Comparative evaluation of soil accumulation of light stabilizers from biodegradable mulching films versus conventional polyethylene ones.

Light stabilizers are commonly used as additives in mulching films and have environmental persistence, bioaccumulation and ecotoxicity. However, their occurrence and distribution in mulching films and accumulation in mulched soils are seldom reported. This study firstly presents a comprehensive screening of 19 light stabilizers in 65 mulching films and 30 farmland soils collected in China, of which five and eight light stabilizers were 100% detected, respectively. The light stabilizer concentration in biodegradable mulching films was significantly higher than that in polyethylene ones, with median concentrations of 1.75 × 106 µg/kg and 4.86 × 103 µg/kg, respectively. Furthermore, a positive correlation was observed between the light stabilizer concentration in mulching films and in soils. This indicates that mulching films play a critical role in the accumulation of light stabilizers in farmland soils, and biodegradable mulching films significantly increase benzotriazole light stabilizers in soils. Although the light stabilizer concentration in farmland soil is relatively low, the sustainable quantities of mulching film input and the long-term accumulation will still pose a threat to the ecological environment and organism health. Consequently, our work reveals the occurrence and environmental risk of light stabilizers in mulching films and farmland soils and brings attention to light stabilizers in the soil environment.

[Determination of 15 halogenated polycyclic aromatic hydrocarbons in aquatic products by stable isotope dilution coupled with gas chromatography-triple quadrupole mass spectrometry].

Halogenated polycyclic aromatic hydrocarbons (H-PAHs), including chlorinated polycyclic aromatic hydrocarbons (Cl-PAHs) and brominated polycyclic aromatic hydrocarbons (Br-PAHs), are compounds in which one or more hydrogen atoms replaced by chlorine or bromine atoms. These compounds are not only difficult to degrade but also highly fat soluble and toxic. They are a new type of high-risk organic pollutants with structures similar to those of dioxins, and their toxicity is even higher than that of the parent polycyclic aromatic hydrocarbons (PAHs). The bioaccumulation of H-PAHs can be predicted by their octanol-water partition coefficient (Kow); in general, higher bioaccumulation capacity and Kow values indicate greater fat solubility. Therefore, animal-derived foods with higher fat contents, such as animal meat, milk, aquatic products, and their processed forms, are more likely to be contaminated with higher contents of H-PAHs than those with lower fat contents. In this work, a gas chromatography-triple quadrupole mass spectrometry (GC-MS/MS) method coupled with stable isotope dilution was established to determine 15 H-PAHs in aquatic products. The instrument and pretreatment methods were systematically optimized. The GC-MS/MS used in this method can effectively eliminate matrix interferences and features high sensitivity and low analytical cost; thus, it has good application prospects. The samples were added with an isotope internal standard before extraction to calibrate the loss of the tested substance during the pretreatment process, extracted by accelerated solvent extraction, purified using gel permeation chromatography and PRiME HLB columns, and then analyzed by GC-MS/MS. The use of two DB-5MS chromatographic columns (30 m×0.25 mm×0.25 µm) and microplate fluidics technology to connect chromatographic columns 1 and 2 in series led to better separation effects, good peak shapes, and high target compound responses. The 15 H-PAHs demonstrated good linearities in the range of 1-50 µg/L, with correlation coefficients (r) greater than or equal to 0.993. The relative standard deviation (RSD) values of the relative response factor (RRF) of the H-PAHs were less than 9%, the method detection limit (MDL) was 0.009-0.072 µg/kg, and the method quantification limit (MQL) was 0.031-0.240 µg/kg. Three spiked levels of 0.25, 1.0, 2.5 µg/kg were added to the blank samples to determine the recovery and precision. The recoveries for these spiked levels were 74.6%-116.8%, 77.8%-123.2%, and 71.9%-124.8%, respectively, and the corresponding RSDs were 0.6%-8.2%, 0.6%-9.0%, and 0.4%-10.6%, respectively. The total actual content of H-PAHs in aquatic product samples was 0.60-3.54 µg/kg. Among the H-PAHs investigated, 9-chlorophenanthrene (9-ClPhe) showed the greatest detection rate (100%) and highest content (1.15 µg/kg), indicating that H-PAHs widely exist in aquatic products. Thus, further assessment of the dietary exposure risk of these compounds is necessary. The developed method simplifies the pretreatment step, and has the advantages of simplicity, rapid analysis, high recoveries, and good stability. It is suitable for the qualitative and quantitative analysis of H-PAHs in actual aquatic product samples and provides reliable technical support for the residue status and risk assessment of H-PAHs in aquatic products.

Discovery of ML210-Based glutathione peroxidase 4 (GPX4) degrader inducing ferroptosis of human cancer cells.

Ferroptosis is an iron-dependent cell death caused by the accumulation of lipid peroxidation. The glutathione peroxidase 4 (GPX4) is an antioxidative enzyme and a major regulator of ferroptosis. Targeting GPX4 has become a promising strategy for cancer therapy. Here in this article, we designed and synthesized a series of GPX4 degraders using ML210 as a warhead. DC-2 among them has been found to have the best degradation activity with the DC50 value of 0.03 µM in HT1080 cells. It also showed an obvious cell growth inhibition effect with the IC50 value of 0.1 µM in HT1080 cells. Mechanism research showed that DC-2 induced GPX4 degradation via the ubiquitin-proteasome pathway and autophagy-lysosome pathway. GPX4 degradation induced by DC-2 could result in the accumulation of ROS and subsequent ferroptosis. The pharmacodynamics study showed that DC-2 could reduce the GPX4 level in HT1080 tumor tissue in mice and has a good safety profile. Above all, a potent and safe compound DC-2 has been found to induce GPX4 degradation and subsequent ferroptosis. This study may lay the foundation for a highly efficient and safe drug with a new mechanism for cancer therapy.

Structure-activity relationship study of RSL3-based GPX4 degraders and its potential noncovalent optimization.

Ferroptosis is an iron-dependent, non-apoptotic form of cell death involving in various disease processes. Mechanistically, glutathione peroxidase 4 (GPX4) which belongs to the redox enzyme can convert lipid hydroperoxides into innocuous lipid alcohol to protect cells from ferroptosis. Therefore, targeting manipulation of GPX4 may represent a promising strategy for regulating cell redox homeostasis and ferroptosis. In this work, we designed, synthesized and evaluated a series of RSL3-based GPX4 degraders using PROTAC strategy. The structure-activity relationship of these compounds with different E3 ligase ligands, linker lengths and chemical compositions was systematically studied. Compound R17 with carbon chain linker and lenalidomide E3 ligand was selected as the most potent GPX4 degrader for degrading GPX4 protein in nanomolar level either in wild tumor cells or in drug-resistant tumor cells. We also optimized the POI ligand of R17 with chloracetylamine replaced to propionamide to construct noncovalent GPX4 degrader NC-R17. Such noncovalent modification led to a moderate GPX4 degradation activity and represents a promising strategy for the development of noncovalent GPX4 PROTACs. In general, we screened a set of GPX4 degraders to give the compound R17 with excellent protein degradation activity, and further optimization gave the noncovalent degrader NC-R17 with moderate efficacy. These results lay a firm foundation for the discovery of novel anti-tumor drugs targeting GPX4 and offer the proof of concept for the design of noncovalent GPX4 PROTACs.

Updated Progress of the Copper-Catalyzed Borylative Functionalization of Unsaturated Molecules.

Borylation has become a powerful method to synthesize organoboranes as versatile building blocks in organic synthesis, medicinal chemistry, and materials science. Copper-promoted borylation reactions are extremely attractive due to the low cost and non-toxicity of the copper catalyst, mild reaction conditions, good functional group tolerance, and convenience in chiral induction. In this review, we mainly updated recent advances (from 2020 to 2022) in the synthetic transformations in C=C/C≡C multiple bonds, and C=E multiple bonds mediated by copper boryl systems.

Distribution properties of ultraviolet absorbents in different species of biodegradable plastics.

Ultraviolet absorbents (UVAs) in the environment have been of increasing concern because of their potential toxicity. However, data on UVAs in the biodegradable plastics are still limited. In this work, we determined the concentrations of 13 UVAs in 6 different types of biodegradable plastic products from Beijing, China, by an ultra-high-performance liquid chromatography with mass spectrometry and found the total concentrations in the range of 37.21-1,138,526 ng g-1. These target UVAs, BP (benzophenone), BP-3, BP-12, UV-328, UV-234, UV-326, UV-329, UV-360 and UV-P are prevalent in the plastic bags, garbage bags, food packaging bags, plastic lunch boxes and tableware, product packing bags and mulch films, except for BP-1, UV-320, UV-327 and UV-PS. This finding showed that the total concentrations of the 13 UVAs in biodegradable mulch films (mean: 1,138,527 ng g-1) were several orders of magnitude higher than those in the other 5 categories of samples (mean: 37.21-186.9 ng g-1). And the UV-328 and BP-1 were the most important components of UVAs in the biodegradable mulch films, with the levels ranging of 726,568-1,062,687 ng g-1 and 317,470-506,178 ng g-1, respectively. As the majority of UVAs were detected in biodegradable plastics, the potential risk of UVAs exposure may exist in the environment with the large-scale use of biodegradable plastics.

Discovery of Coumarin-Based MEK1/2 PROTAC Effective in Human Cancer Cells.

The RAF/MEK/ERK pathway is a crucial signal path which is closely associated with the proliferation, differentiation, and apoptosis of tumors. MEK1/2 is a key kinase target in the pathway, with ERK1/2 acting as the main substrate of it. Despite the rapid development of MEK1/2 inhibitors, acquired resistance still happens and remains a significant problem. Most of the inhibitors possess a similar diarylamine scaffold. Here we designed and synthesized a series of MEK1/2 degraders based on a coumarin derivative which was a potent non-diarylamine allosteric MEK1/2 inhibitor. P6b among them showed the most potent degradation effect, with DC50 values of 0.3 µM and 0.2 µM in MEK1 and MEK2 degradation, respectively. An antiproliferation assay showed that it more significantly inhibits the growth of A375 cells (IC50= 2.8 µM) compared to A549 cells (IC50 = 27.3 µM). To sum up, we discovered P6b with a non-diarylamine scaffold for the first time as a potent MEK PROTAC effective in human cancer cells.

Mulch film: An overlooked diffuse source of organic ultraviolet absorbers in agricultural soil.

Ultraviolet absorbers (UVAs) are emerging pollutants of concern owing to their environmental persistence and endocrine-disrupting effects. UVAs are added to agricultural films to prevent UV-induced degradation, potentially leading to the release of UVAs into the soil. In this study, the occurrence of four frequently used UVAs (UV-324, UV-326, UV-328, and UV-531) in film-mulched agricultural soils (using conventional polyethylene films and biodegradable films) was investigated. Results showed that the UVA concentrations were several orders of magnitude higher in film-mulched soil (mean 91.4 µg/kg) than in unmulched soil (mean 0.08 µg/kg), indicating that mulch films are important sources of UVAs released into agricultural soil. Notably, the mean UVA concentration was up to 10 times higher in biodegradable-film-mulched soils than in polyethylene (PE) film-mulched soils; this result is consistent with our finding that the mean UVA concentration was 448 times higher in commercial biodegradable films than in PE films. In simulated migration experiments, UVAs migrated more readily into the soil from the biodegradable film than from the PE film. To our knowledge, this is the first report demonstrating that the use of mulch films may cause the accumulation of UVAs in agricultural soils as non-point sources. In particular, biodegradable plastic mulches can release more UVAs into soils.

An enzyme-free, ultrasensitive strategy for simultaneous screening of the p-nitrophenyl substituent organophosphorus pesticides.

An enzyme-free, sensitive, and convenient approach was reported for the P-nitrophenyl substituent organophosphorus pesticides (NSOPs) of paraoxon-methyl (PM), paraoxon-ethyl (PE), parathion-methyl (PTM) and parathion-ethyl (PTE)) by indirectly quantification of the 4-nitrophenol (4-NP, hydrolysis product of the NSOPs). NaOH instead of hydrolase/nanozyme was applied, and temperature, pH, ultrasound was investigated to improve the NSOPs hydrolysis. Under the optimized conditions, the hydrolysis efficiencies were up to 99.9 %, 99.9 %, 99.6 %, 96.0 % for PM (10 min), PE (30 min), PTM (90 min) and PTE (120 min), based on which a low detection limits of 0.06 (PM), 0.07 (PE), 0.06 (PTM) and 0.07 (PTE) ppb were calculated with the 4-NP detection limit (0.03 ppb). Furthermore, the method exhibited good performance for the NSOPs with recoveries from 88.87 % to 100.33 % in real samples. This indirect approach offered an ultrasensitive alternative for the NSOPs detection, which holds great potential in practical application for the assessment of food safety and environmental risks.

Ultratrace mercury speciation analysis in rice by in-line solid phase extraction - liquid chromatography - atomic fluorescence spectrometry.

For the first time, Hg2+ and methylmercury speciation analysis was accomplished by in-line SPE-LC-AFS. After modification with 0.1 mL of 0.001% (m:v) sodium diethyldithiocarbamate, a C18 microcolumn retained Hg2+ and MetHg in rice extract within 3 min; the captured Hg species were separated within 12 min in 0.25% (v:v) 2-mercaptoethanol + 60 mmol L-1 (m:v) ammonium acetate + 4% (v:v) acetonitrile. Under optimized conditions, the detection limits were 0.3 ng L-1 for Hg2+ and 0.2 ng L-1 for MetHg, respectively, with 10 mL injection vs. 0.1 mL eluent; in-line SPE achieved âˆ¼ 100x enrichment. Method precision and accuracy were satisfactory at < 2% relative standard deviations (RSDs) for 20 ng L-1 of Hg2+ and MetHg and 95-102% recoveries for real rice samples. In-line SPE obviated human involvement and avoided invalid transportation between interfaces, rendering this SPE-LC-AFS method easy, compact, robust, yet sensitive in mercury speciation analysis to uphold food safety.

Tissue distribution of phthalates in celery under different cultivation patterns and associated dietary exposure.

To investigate tissue distribution, spatial difference, temperature variation, and potential health risks of PAEs in vegetables, celery was used as a model plant. Celery samples were collected from open fields and greenhouses from two provinces in China over four seasons. Celery tissues were analyzed for 16 PAE compounds by gas chromatography-tandem mass spectrometry. The total content of PAEs was 89.0-1130.3 µg kg-1 dry weight (dw) in stems and 155.0-2730.8 µg kg-1 dw in leaves. Concentrations of PAEs in celeries showed notable spatial differences (P < 0.05), and the levels in samples from open fields were lower than those in samples from plastic greenhouses. In celeries from greenhouses, higher PAE concentrations were observed for plants grown at high temperatures than in plants grown at low temperatures. Discrepancies in tissue distribution indicated different uptake pathways of PAE contaminants. Risk assessments to humans found that both carcinogenic risks and non-carcinogenic risks of PAEs via celery consumption were at an acceptable level. Further research should consider other exposure pathways of PAEs and pay special attention to reducing PAE contents in vegetables.

Evaluation of efficiency and safety of muscular region's acupuncture treatments for knee osteoarthritis: A protocol for systematic review and network meta-analysis.

BACKGROUND: As a chronic degenerative disease, knee osteoarthritis (KOA) is mainly characterized by loose ligaments around the knee joint, degeneration of cartilage in the knee joint, and atrophy of surrounding muscles. According to related investigations, the incidence of knee osteoarthritis in China is 8.1%, of which 10.3% are women and 5.7% are men. Therefore, in order to improve the therapeutic effect of KOA, we must constantly explore new ways to treat the disease. The purpose of this study is to evaluate the effectiveness and safety of acupuncture with needle knife, blade needle, long-round needle, fire needle, micro-needle knife with conventional acupuncture intervention in KOA. METHODS: Computer search of PubMed, Cochrane Library, Web of Science, CNKI, Wangfang, and VIP database, search for randomized controlled trials of muscular region's acupuncture therapy on KOA, the search time limit is to build the database until July 9, 2021. To ensure the comprehensiveness of the search, relevant references and conference literature are also included. After 2 researchers independently screened the literature, extracted data, and evaluated the risk of bias in the included studies, the Stata 14.0 software was used for data analysis. RESULTS: The effectiveness and safety of muscular region's acupuncture in the treatment of patients with KOA will be systematically evaluated. CONCLUSION: The results of this study will provide strong evidence to determine whether muscular region's acupuncture is effective in the treatment of KOA. REGISTRATION NUMBER: INPLASY202170031 (https://inplasy.com/inplasy-2021-7-0031/).

Trifluralin residues in soils from main cotton fields of China and associated ecological risk.

Trifluralin is a widely used dinitroaniline herbicide in cotton fields of China but is highly persistent in the environment and can act as a biotoxin and cause genotoxicity to terrestrial organisms, including humans. In this study, the concentrations and distribution of trifluralin residues in 139 soil samples from the major cotton-producing areas of China were investigated. The trifluralin concentrations ranged from ND (not detected) to 66.39 µg/kg dry weight (dw), with a geometric mean of 4.13 µg/kg dw. The detection frequency of trifluralin in Hebei (75%) was higher than that in Xinjiang (66%) and Shandong (40%), but the mean trifluralin concentration was highest in Xinjiang (5.98 µg/kg dw), followed by Hebei (5.06 µg/kg dw) and Shandong (3.19 µg/kg dw). No trifluralin residues were detected in cotton soil in Anhui, Jiangxi and Hunan. The residual amount of trifluralin in soil was significantly correlated with the soil organic matter content. The risk quotient method was used to evaluate the ecological risks associated with trifluralin. Results indicated that trifluralin in all the samples had a low risk to earthworms, but trifluralin in same cotton soils showed high risks to wheat, barley and lucerne. Overall, our work is helpful to understand the residual situation of trifluralin in Chinese cotton soil, to assess the environmental risk of trifluralin, and to control the use and safety of trifluralin in cotton field cultivation.

Characterization of free, conjugated, and bound phenolics in early and late ripening kiwifruit cultivars.

BACKGROUND: Kiwifruit (Actinidia) has long been called the 'king of fruits' because of its unique flavor and the wide range of bioactive compounds which contains ascorbic acid, phenolics and minerals. These bioactivities are influenced by species and cultivar. However, to date few studies are concerned with the effect of ripening time on fruit quality. Here, early and late ripening kiwifruits were investigated to determine their content of ascorbic acid, organic acid, and phenolic compounds. RESULTS: Early ripening cultivars contained higher quinic acid and malic acid, while citric acid were found in large amounts in late ripening kiwifruits. Most of the early ripening cultivars contained higher free phenolic fractions than the late ripening fruits, mainly due to the high levels of epicatechin. However, conjugated phenolics, mainly including caffeic and 2,3,4-trihydroxybenzoic acid, achieved higher levels in the late ripening cultivars. Free phenolics were higher than conjugated phenolics in the early ripening cultivars. Principal component analysis revealed some key compounds that differentiated the kiwifruits, and all the kiwifruits were divided into two subgroups as early and late ripening cultivars. CONCLUSION: Ripening time had a great impact on the accumulation of bioactive compounds. The early ripening cultivars, compared to the late ripening ones, were characterized by higher levels of free neochlorogenic acid and epicatechin, while the late ripening kiwifruits contained higher amounts of conjugated phenolics. Results from this study provide further insights into the health-promoting phenolic compounds in kiwifruit, and also provide good evidence to aid consumer selection. © 2021 Society of Chemical Industry.

Occurrence of dioxin-like POPs in soils from urban green space in a metropolis, North China: implication to human exposure.

Urban green space is a special space for urban life and natural contact and has an important impact on human health. However, little information is available on dioxin-like persistent organic pollutants (POPs) in the soils from the specific areas. We measured the concentrations of polychlorinated naphthalenes (PCNs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), and polychlorinated biphenyls (PCBs) in the soils from urban green space in a metropolis, North China, and found total concentrations of PCDD/Fs, PCBs, and PCNs in the range of 11.5-91.4, 14.7-444, and 82.5-848 pg/g, respectively. It was worth to notice that the concentrations of PCDD/Fs in public park soil from urban center were significantly higher than those in the road greenbelts and resident lawns (Kruskal-Wallis test, p = 0.004). The source analysis indicated that sewage sludge from wastewater treatment plants were important sources of PCNs and PCDD/Fs in urban green land soils, and atmospheric deposition from municipal solid waste incinerator (MSWI) also play an important role in PCDD/F sources. The rough exposure risk evaluation showed that the residents were at a safe level with the daily doses being 0.172-3.144 fg/kg BW/day for children and 0.022-0.406 fg/kg BW/day for adult. Due to the complex and variable sources of PCDD/Fs in urban areas, dioxin-like POPs in urban green land should be given more attention to weaken human exposure.

Strong sorption of two fungicides onto biodegradable microplastics with emphasis on the negligible role of environmental factors.

Microplastics have attracted much attention in recent years because they are able to interact with other pollutants including pesticides, with implications for the potential risks to biota. However, the sorption behavior of pesticides on microplastics, especially on biodegradable microplastics which are promising alternatives to conventional polymers, has been insufficiently studied. In this study, triadimefon and difenoconazole were selected as model triazole fungicides, and their sorption behavior on a typical biodegradable microplastics (PBS: polybutylene succinate) and two conventional polyethylene (PE) and polyvinyl chloride (PVC) microplastics was investigated with batch experiments in an aqueous solution. PBS presented the highest sorption capacity for triadimefon (104.2 ± 4.8 µg g-1) and difenoconazole (192.8 ± 2.3 µg g-1), which was 1.8- and 1.3-fold that on PE and 4.4- and 7.4-fold that of PVC, respectively. The results of sorption kinetic and isotherm modeling were better fit by a pseudo-second order model and linear model, respectively. More importantly, the effects of environmental factors (pH, salinity and dissolved organic matter) on the sorption behavior were investigated. Fungicide sorption on PBS was generally not affected by salinity, pH or dissolved organic matter. However, in contrast, salinity and dissolved organic matter both significantly decreased sorption on PE and PVC. The results showed that not only the sorption capacities of biodegradable microplastics but also their responses to environmental factors are quite different from those of conventional microplastics. This finding highlights the importance of the role played by biodegradable microplastics in the accumulation and transportation of organic pollutants.

Benefit-risk assessment of dietary selenium and its associated metals intake in China (2017-2019): Is current selenium-rich agro-food safe enough?

Dietary consumption of selenium-rich agro-food is an effective way to avoid selenium deficiency diseases, however, over consumption of selenium-rich agro-food will result in potential risk of selenosis and problems with associated metals. In this study, we measured the concentrations of selenium and its associated metals in 2756 common and 4894 selenium-rich agro-food samples in 10 regions of China. We found that selenium-rich rice, flour, edible fungi and algae, meat, and tea contain higher levels of associated metals than other selenium-rich agro-food samples. Increasing the consumption of selenium-rich agro-food could make the actual intakes (AIs) of selenium for all population to meet respective recommended daily intakes (RDIs). Benefit-risk assessment results indicated that increasing the consumption of selenium-rich agro-food make AIs of selenium for all populations meet RDIs, chromium intakes for people under 18 years old exceed provisional tolerated daily intake (PTDIs), while arsenic and cadmium intakes are close to PTDIs. The main dietary contributors of selenium, chromium, arsenic and cadmium were meat, edible fungi and algae, rice, and rice, respectively. The study supported the consumption of selenium-rich agro-food for effective selenium supplement, but also emphasized potential risk from associated metals in selenium-rich agro-food, especially chromium.