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1.
Small ; 20(22): e2309253, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38126674

RESUMO

Atomic thick 2D materials hold great potential as building blocks to construct highly permeable membranes, yet the permeability of laminar 2D material membranes is still limited by their irregularity sheep track-like interlayer channels. Herein, a supramolecular-mediated strategy to induce the regular assembly of high-throughput 2D nanofluidic channels based on host-guest interactions is proposed. Inspired by the characteristics of motorways, supramolecular-mediated ultrathin 2D membranes with broad and continuous regular water transport channels are successfully constructed using graphene oxide (GO) as an example. The prepared membrane achieves an ultrahigh water permeability (369.94 LMH bar-1) more than six times higher than that of the original membranes while maintaining dye rejection above 98.5%, which outperforms the reported 2D membranes. Characterization and simulation results show that the introduction of hyaluronate-grafted ß-cyclodextrin not only expands the interlayer channels of GO membranes but also enables the membranes to operate stably under harsh conditions with the help of host-guest interactions. This universal supramolecular assembly strategy provides new opportunities for the preparation of 2D membranes with high separation performance and reliable and stable nanofluidic channels.

2.
Ecotoxicol Environ Saf ; 279: 116517, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38805830

RESUMO

With increasing urbanization and rapid industrialization, more and more environmental problems have arisen. Phthalates (PAEs) are the foremost and most widespread plasticizers and are readily emitted from these manufactured products into the environment. PAEs act as endocrine-disrupting chemicals (EDCs) and can have serious impacts on aquatic organisms as well as human health. In this study, the water quality criteria (WQC) of five PAEs (dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), butyl benzyl phthalate (BBP) and di(2-ethylhexyl) phthalate (DEHP)) for freshwater aquatic organisms were developed using a species sensitivity distribution (SSD) and a toxicity percentage ranking (TPR) approach. The results showed that long-term water quality criteria (LWQC) of PAEs using the SSD method could be 13.7, 11.1, 2.8, 7.8, and 0.53 µg/L, respectively. Criteria continuous concentrations (CCC) of PAEs were derived using the TPR method and determined to be 28.4, 13.1, 1.3, 2.5, and 1.6 µg/L, respectively. The five PAEs are commonly measured in China surface waters at concentrations between ng/L and µg/L. DBP, DEHP, and di-n-octyl phthalate (DnOP) were the most frequently detected PAEs, with occurrence rates ranging from 67% to 100%. The ecological risk assessment results of PAEs showed a decreasing order of risk at the national level, DEHP, DBP, DMP, DEP, DnOP. The results of this study will be of great benefit to China and other countries in revising water quality standards for the conservation of aquatic species.


Assuntos
Monitoramento Ambiental , Água Doce , Ácidos Ftálicos , Plastificantes , Poluentes Químicos da Água , Qualidade da Água , Ácidos Ftálicos/análise , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Qualidade da Água/normas , Água Doce/química , Monitoramento Ambiental/métodos , Plastificantes/análise , Plastificantes/toxicidade , Disruptores Endócrinos/análise , Disruptores Endócrinos/toxicidade , Organismos Aquáticos/efeitos dos fármacos , Ésteres , China , Animais , Dibutilftalato/toxicidade
3.
Ecotoxicol Environ Saf ; 268: 115713, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37995619

RESUMO

The occurrence and profiles of organophosphate esters (OPEs) were studied in indoor and outdoor dusts from various microenvironments, including forty-seven outdoor dusts from green belts, roads, parks and residence areas, seventy-seven indoor dusts from private cars, print shops, taxis, furniture shops, offices, dormitories, shopping malls and residences house in different districts in Beijing. The total concentrations (Σ12OPEs) were eighteen times higher in indoor dusts (7.14 ×102 to 2.24 ×104 ng/g) than in outdoor dusts (36.0-1.56 ×103 ng/g). OPEs concentrations in samples from taxi and private cars were obviously higher than other indoor microenvironments. Both indoor and outdoor microenvironments also showed different compositional profiles of OPEs, indicating that polyurethane foam/building materials and hydraulic fluids/plastics were the greatest contributions in different microenvironments, with chlorinated alkyl phosphates (Cl-OPEs) being the predominant compound in both indoor dust (52.1-86.5%) and outdoor dust samples (42.6-81.3%). The uncertainty was reduced by Monte Carlo simulation, and the pollution levels of 50th and 95th percentiles were employed to calculate the average daily dosage, which was then used to calculate hazard quotient (HQ) for assessing the health risks to adults and children. Results showed that OPEs were safe even at extremely consumed concentration percentile (95th) in all groups.


Assuntos
Poluição do Ar em Ambientes Fechados , Retardadores de Chama , Criança , Adulto , Humanos , Pequim , Poeira/análise , Retardadores de Chama/análise , Ésteres/análise , Monitoramento Ambiental , Organofosfatos/análise , Medição de Risco , Poluição do Ar em Ambientes Fechados/análise , China
4.
J Environ Manage ; 342: 118344, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37320921

RESUMO

Freshwater biodiversity and ecosystem services might decline due to exposure to chemicals. However, researchers have devoted much attention to the potential risks of emerging contaminants, while placing less effort on historical pollutants, such as the surfactant, linear-alkylbenzene-sulfonate (LAS), which is a major component of widely used synthetic detergents worldwide. In this study, a multilevel risk assessment approach was used to assess risks posed by LAS to aquatic organisms, on a wide spatial scale, based on various assessment endpoints. Additionally, bottom-up approaches were used to assess contributions of LAS source discharges to aquatic environments. Concentrations of LAS in surface waters of China ranged from less than the limit of detection to 14,200 µg/L. The predicted no effect concentration (PNEC) based on adverse effects on reproduction is 15 µg/L, which is slightly less than the PNEC based on other endpoints. 99% of surface waters in Chaohu Lake and the Hai River (Ch: Haihe) were predicted to pose a risk to growth of aquatic organisms, with a protection threshold of 5% of species (HC5). Discharges of LAS were estimated using activity data and emission factors for 280 major cities in the basin. Rural domestic sources were the main source of LAS to surface waters. These outcomes provided a process for developing comprehensive management and control approaches to help researchers and policymakers effectively manage water resources affected by increasing concentrations of LAS.


Assuntos
Ácidos Alcanossulfônicos , Poluentes Ambientais , Ecossistema , Lagos
5.
J Environ Manage ; 339: 117822, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37054589

RESUMO

Triadimefon is ubiquitous in various environmental media. Although toxicity of triadimefon to individual of aquatic organisms has been confirmed, its effect on organisms at population level remain poorly understood. In this study the long-term effect of triadimefon on individual and population of Daphnia magna were studied using multi-generational experiments and matrix model. Development and reproduction of three generations of F1 and F2 were significantly inhibited with the triadimefon concentration of 0.1 mg/L (p < 0.01). Toxicity of triadimefon to the offspring was stronger than to the parent (p < 0.05). When triadimefon concentration was higher than 0.1 mg/L, both population number and intrinsic rate of increase showed a decreasing trend with the increasing exposure concentration. Age structure of the population also tended to decline. Toxicity threshold derived on population-level was between mortality-based LC50 and reproduction-based NOEC of Daphnia magna, and also between acute toxicity and chronic toxicity derived from species sensitivity distribution (SSD). The risk of population level derived from risk quotient was low for most areas, and the results derived from probability risk showed that the expected loss of intrinsic rate of increase of population was 0.0039 without considering other factors. Compared to the individual-level, the ecological risks at the population level were closer to the actual situation of the ecosystem response to the chemical pollution.


Assuntos
Fungicidas Industriais , Poluentes Químicos da Água , Animais , Daphnia/fisiologia , Fungicidas Industriais/toxicidade , Fungicidas Industriais/química , Ecossistema , Poluentes Químicos da Água/toxicidade , Reprodução
6.
Environ Geochem Health ; 45(6): 3637-3651, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36459339

RESUMO

Antimony mining activities can result in serious contamination of soil by heavy metals, which represents a risk to human health. In this study, the contamination and sources of 14 heavy metals, and their risks to both ecosystem and public health from these metals at an antimony mining site in Guizhou Province in China were explored. The results showed that the mean concentrations of Hg, Cu, As, Se, Cd, Sn, Sb and Pb were 3.73, 2.49, 13.99, 38.32, 1.11, 1.61, 305.33, 1.59 times than their local background levels. Sb, Se, As and Hg presented the relatively heavy pollution, wherein Sb (EI = 2137.34 > 320), Hg (EI = 150.26 > 80) and As (EI = 139.92 > 80) also posed the strong ecological risk. The sources identification illustrated Hg, Pb, As, Bi, Cr, Sb, Cd and Zn were attributed to industrial activities, Ni, Co, Au and Cu (p < 0.01) were derived from a combination of a lithogeny origin and anthropogenic source, whereas Se was of natural origin. Health risk assessment demonstrated that Ni, Cr and As presented both the unacceptable noncarcinogenic and carcinogenic risk, and Sb (HI = 1.44E+03) and Cd (HI = 2.91E+00) posed unacceptable noncarcinogenic risk to the local resident. Furthermore, children in the 1-6 age group (HI = 7.83E+02) were more sensitive to noncarcinogenic risk, and the 6-18 age group (CRI = 2.39E-02) as more prone to carcinogenic risk. The dermal contact was the predominant exposure pathway of noncarcinogenic and carcinogenic risks with a contribution rate of over 97% for all age groups. Overall, this research provided the comprehensive information on heavy metals in an antimony mining sites, and the related heavy metals should be paid attention for ensuring soil safety and protecting local people's health.


Assuntos
Mercúrio , Metais Pesados , Poluentes do Solo , Criança , Humanos , Solo , Antimônio , Ecossistema , Monitoramento Ambiental/métodos , Cádmio , Chumbo , Poluentes do Solo/toxicidade , Poluentes do Solo/análise , Metais Pesados/toxicidade , Metais Pesados/análise , Mineração , China , Medição de Risco , Carcinógenos
7.
Ecotoxicol Environ Saf ; 238: 113618, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35551044

RESUMO

The occurrence and risk of organophosphate esters (OPEs) has become a global concern in recent years. This study investigated the occurrence, spatial distribution, and potential sources of thirteen OPEs and their associated ecological and human health risks in water samples from the largest freshwater lake, Poyang Lake, together with its five major inflow rivers and the water channel to Yangtze River. The total OPEs concentrations ranged from 38.44 ng/L to 428.94 ng/L, and the largest tributary Ganjiang River was much more polluted than other rivers. Chlorinated OPEs, such as tris (1-chloro­2-propyl) phosphate and tri (2-chloroethyl) phosphate occupied the dominant composition of OPEs in the research area. Principal component analysis with multiple linear regression, positive matrix factorization, and correlation analysis were used to apportion the potential sources of OPEs in surface water. The combined contribution of polyvinyl chloride, polyester resins, and polyurethane foam (68.64%), antifoam agent and hydraulic fluids (21.50%), and the release of decorative materials and electric equipment from indoor (9.86%) were identified as the OPEs sources in the study region. The risk quotients (RQs) showed the ecological risk was negligible, but 2-ethylhexyl diphenyl phosphate exposures posed medium ecological risk to aquatic organisms. The carcinogenic and non-carcinogenic risks of the target OPEs were below the theoretical risk threshold values, however, toddlers were much more sensitive to the OPEs exposure in surface water than teenagers and adults. Oral ingestion was the principal exposure pathway, and the health risk via oral ingestion was 1-2 orders of magnitude higher than dermal contact exposure route.


Assuntos
Retardadores de Chama , Poluentes Químicos da Água , Adolescente , China , Medicamentos de Ervas Chinesas , Monitoramento Ambiental , Ésteres/análise , Retardadores de Chama/análise , Humanos , Lagos , Organofosfatos/análise , Organofosfatos/toxicidade , Fosfatos/análise , Medição de Risco , Água/análise , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
8.
Ecotoxicol Environ Saf ; 242: 113928, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35926407

RESUMO

The occurrence, distribution, and ecological risks of psychoactive substances (PSs) in Qinghai-Tibet Plateau (QTP) was investigated in this study. The surface water samples were collected in July in 2020 from five major water bodies, and 9 PSs were determined by liquid chromatography-mass spectrometry. The mean concentrations of the total PSs were 2.19-96.86 ng/L in lakes and 4.56-34.47 ng/L in rivers. Amphetamine (AMP) was the predominant contaminant both in lakes and rivers with a mean concentration of 12.21 ± 22.76 ng/L and 9.83 ± 6.14 ng/L, respectively. The compositions of PSs in lakes and rivers were significantly different. AMP, methadone (MTD), 3,4-methylenedioxyamphetamine (MDA), and ketamine (KET) were the most detected contaminants in lakes, while in rivers AMP, MDA, heroin (HER), and methamphetamine (METH) were the most detected ones. Concentrations of AMP and MTD, the two predominant drugs, varied spatially, with the decreasing concentration of AMP in the order of Huangshui River > Yamzhog Yumco Lake > Qinghai Lake > Lhasa River > Namco Lake, and of MTD in the order of Qinghai Lake > Namco Lake > Huangshui River > Yamzhog Yumco Lake. The risk quotients (RQs) of PSs ranged from 4.44 × 10-6 to 4.32 × 10-2, indicating a low risk of PSs in the aquatic ecosystem in QTP. Compared with other research in the world, the contamination of psychoactive substances in the Qinghai-Tibet Plateau was at relatively low levels with low ecological risks.


Assuntos
Rios , Poluentes Químicos da Água , China , Ecossistema , Monitoramento Ambiental , Lagos/química , Rios/química , Tibet , Água/análise , Poluentes Químicos da Água/análise
9.
Nanotechnology ; 32(8): 085703, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33176292

RESUMO

The mechanism of the nanofiltration (NF) membrane separation of Mg2+ and Li+ needs to be further investigated, but some commonly used model theories are abstract, which makes them difficult to understand. More importantly, the relationship between the membrane charge and separation performance of Mg2+ and Li+ cannot be quantitatively analyzed. It is worth studying these challenges and providing a performance boost for Mg2+/Li+ filtration applications of NF membranes. Here, various NF membranes, with the membrane volumetric charge density increasing from -4.69 to 7.02 mol · m-3, were fabricated via interfacial polymerization. For these membranes, the separation factor S Mg,Li was decreased from 0.41 to 0.20. Importantly, the visual simulation results were consistent with the experimental results as a whole. The separation factor S Mg,Li decreased with the increase of volumetric charge density, and the minimum separation factor S Mg,Li of the NF membranes was 0.20 (experiment) and 0.17 (simulation), respectively. This meant that the performance of the positively charged NF membrane was not fully developed. Furthermore, we analyzed the relationship between the membrane charge and separation performance, and visualized the simulation of the NF membrane filtration and separation.

10.
Environ Res ; 200: 111362, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34048744

RESUMO

Drugs of abuse are a group of emerging contaminants. As the prevalence of manufacture and consumption, there is a growing global environmental burden and ecological risk from the continuous release of these contaminants into environment. The widespread occurrence of drugs of abuse in waste wasters and surface waters is due to the incomplete removal through traditional wastewater treatment plants in different regions around the world. Although their environmental concentrations are not very high, they can potentially influence the aquatic organisms and ecosystem function. This paper reviews the occurrence of drugs of abuse and their metabolites in waste waters and surface waters, their bioaccumulation in aquatic plants, fishes and benthic organisms and even top predators, and the toxicological effects such as genotoxic effect, cytotoxic effect and even behavioral effect on aquatic organisms. In summary, drugs of abuse occur widely in aquatic environment, and may exert adverse impact on aquatic organisms at molecular, cellular or individual level, and even on aquatic ecosystem. It necessitates the monitoring and risk assessment of these compounds on diverse aquatic organisms in the further study.


Assuntos
Preparações Farmacêuticas , Poluentes Químicos da Água , Organismos Aquáticos , Bioacumulação , Ecossistema , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
11.
Bull Environ Contam Toxicol ; 103(4): 590-596, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31486910

RESUMO

Antibiotics in manure, soil, wastewater, and groundwater samples from the livestock and poultry farms in Xuzhou City were investigated in the present study. The concentrations of antibiotics in all matrices varied greatly among farms. Total concentrations of fluoroquinolones and macrolides were much higher than those of sulfonamides in manures and soil samples. Total concentrations of antibiotics in wastewater of livestock farms were higher than those of poultry farm. Josamycin (JM) and tilmicosin (TIL) accounted for more than 74% of the nine macrolides in all groundwater samples. Sulfamethizole (SMT), fleroxacin (FLE), cinoxacin (CIN) and JM were the main antibiotics detected in manure and soil samples, while sulfamethoxypyridazine (SMP), sulfameter (SME), SMT, FLE, JM and TIL accounted for a large proportion of antibiotics in surface and groundwater. The risk assessment of target antibiotics revealed that JM in wastewater showed relatively high RQs for aquatic organisms.


Assuntos
Antibacterianos/análise , Monitoramento Ambiental , Poluentes do Solo/análise , Poluentes Químicos da Água/análise , Animais , Galinhas , China , Fazendas , Fluoroquinolonas/análise , Água Subterrânea , Gado , Macrolídeos/análise , Esterco/análise , Aves Domésticas , Medição de Risco , Solo , Águas Residuárias
12.
Environ Sci Technol ; 51(16): 9101-9108, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28735534

RESUMO

Illicit drugs constitute a class of emerging contaminants that has been drawing significant concern due to its potent pharmacological and biological activities. In this study, an in situ passive sampling approach that uses diffusive gradients in thin films (DGT) was successfully tested for measuring ketamine (KET), methamphetamine (METH), and amphetamine (AMP) in water. The diffusion coefficients of KET, METH, and AMP in diffusive gel were (8.13 ± 0.12) × 10-6, (8.55 ± 0.14) × 10-6, and (7.72 ± 0.18) × 10-6 cm2 s-1 at 22 °C, respectively. The capacities of an XAD binding gel for KET, METH, and AMP were 92, 57, and 45 µg per binding gel disc, which were suitable for long-term environmental monitoring. The DGT measurement of these drugs was not influenced by the pH (4 to 9) and the ionic strength (0.001 M - 0.1 M) and unaffected by the water flow, demonstrating the effectiveness of the XAD-based DGT for the in situ monitoring of illicit drugs. DGT samplers were deployed in a WWTP influent and natural rivers in Beijing, China. The ng L-1 levels of the drugs were high in the wastewater influent and low in river waters, with an insignificant fluctuation during the seven-day monitoring. The DGT-measured concentrations were comparable to the average concentrations determined by SPE method, which suggested that the average data measured by DGT could be substituted for high-frequency grab sampling. This study has demonstrated systematically for the first time that DGT is effective and accurate for monitoring illicit drugs in wastewater and surface waters, and provides a powerful tool to investigating the presence, transport, and environmental behaviors of these drugs in the aquatic ecosystem.


Assuntos
Drogas Ilícitas , Águas Residuárias , Poluentes Químicos da Água , Pequim , China , Difusão , Monitoramento Ambiental , Rios
13.
Environ Monit Assess ; 188(3): 193, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26915741

RESUMO

The distribution and potential toxicity of polycyclic aromatic hydrocarbons (PAHs) in the sediments of Liaohe River Basin were investigated in this study. Total concentrations of 16 PAHs (∑PAH16) ranged from 82.5 to 25374.4 µg/kg averaging 3149.2 µg/kg. Three predominant PAHs were fluoranthene, phenanthrene, and pyrene. In Liao River, two-to-three-ring PAHs were dominant taking up 67.2-92.5% of ∑PAH16, whereas sediments in Daliao River system mainly contained four-to-six-ring PAHs ranging from 47.8 to 83.7%. Both petrogenic and pyrogenic sources contributed to the PAH pollution based on diagnostic ratios. The empirical and mechanistic sediment quality guidelines were used to estimate the toxicity risk of PAHs to benthic organisms. The ∑PAH16 in all sediments were significantly lower than probable effect concentrations (PEC), while ∑PAH16 at nine sites of the Daliao River system were between threshold effect concentrations (TEC) and PEC, suggesting that adverse effects were possible at the nine sites. The only individual PAH was acenaphthene whose concentrations were above PEC at some sites, indicating its potential toxicity. Based upon equilibrium partitioning theory and narcosis model, the obtained toxic units for PAH mixtures at all sites were far less than one, implying that the levels of PAH mixtures were acceptable for the protection of benthic fauna. The two evaluation methods lead to the consistent results that benthic organisms inhabiting in the sediments of Liaohe River Basin have no or low risk of adverse effects resulting from exposure to PAHs.


Assuntos
Monitoramento Ambiental , China , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Fenantrenos , Hidrocarbonetos Policíclicos Aromáticos/análise , Pirenos , Rios/química , Poluentes Químicos da Água/análise
14.
Tumour Biol ; 36(7): 5591-6, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25707354

RESUMO

Recent researches have suggested that autophagy may play critical roles in tumorigenesis. Immunity-related GTPase family M (IRGM) is a human protein highlighted for its contribution to autophagy upon inflammation and infections. Studies have shown that IRGM is involved in the development of several cancers. In the current study, we investigated expression of IRGM and gastric cancer. Levels of messenger RNA (mRNA) and protein were examined by real-time reverse transcription PCR (RT-PCR) and Western blot, respectively. Data showed that mRNA level of IRGM was significantly increased in peripheral blood mononuclear cells (PBMCs) of gastric cancer patients than in PBMCs from healthy controls (p > 0.05). Moreover, both mRNA and protein levels were significantly higher in cancer tissues compared to adjacent noncancerous stomach tissues (1.28-fold, p < 0.001; 1.19-fold, p < 0.01, respectively). However, the level of IRGM seemed not to be affected by Helicobacter pylori infection. In addition, we investigated the correlation between IRGM expression and cancer stages and identified that stage IV patients had upregulated mRNA level and protein level of IRGM in cancer tissues than those stage I patients. Our findings suggest that expression of IRGM is dysregulated in gastric cancer and that the molecule may affect progression of the disease.


Assuntos
Proteínas de Ligação ao GTP/biossíntese , RNA Mensageiro/biossíntese , Neoplasias Gástricas/genética , Adulto , Idoso , Autofagia/genética , Feminino , Proteínas de Ligação ao GTP/genética , Infecções por Helicobacter/genética , Infecções por Helicobacter/patologia , Humanos , Leucócitos Mononucleares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Gástricas/patologia
15.
Bull Environ Contam Toxicol ; 93(6): 744-51, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25323038

RESUMO

The occurrence and distribution of polycyclic aromatic hydrocarbons (PAHs) were investigated in water and sediments in Liaohe River Basin. The total PAH concentrations ranged from 111.9 to 2,931.6 ng/L in water and from 92.2 to 295,635.2 ng/g dry weight (dw) in sediments. The PAHs in water were dominated by 2-, 3- and 4-ring PAHs, which accounted for 42.8 %, 39.4 % and 14.2 % of the total PAHs, respectively, while in sediment PAHs were dominated by 3-, 4- and 5-ring PAHs, which accounted for 26.5 %, 44.2 % and 17.4 % of the total PAHs, respectively. The benzo[a]pyrene equivalents for water samples showed that in 37 out of 50 sites the values were greater than the national standard, and the environmental risk assessment indicated that high environmental risk of PAHs existed in sediments. Using the molecular ratio method for the source identification it was concluded that PAHs were determined to be from mixed sources (petroleum and combustion) in Liaohe River system and combustion sources in Daliao River system.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Rios , Poluentes Químicos da Água/análise , Benzo(a)pireno/análise , Benzo(a)pireno/toxicidade , China , Exposição Ambiental , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Medição de Risco , Poluentes Químicos da Água/toxicidade
16.
Foods ; 13(10)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38790843

RESUMO

The effect of sulfuric acid hydrolysis on the Pickering emulsifying capacity of Tartary buckwheat flour (TBF) rich in starch was evaluated for the first time. The results indicate that the sulfuric acid concentration and hydrolysis time had a significant impact on the Pickering emulsifying capacity of acid-hydrolyzed Tartary buckwheat flour (HTBF). A low sulfuric acid concentration (1-2 mol/L) could reduce the particle size of HTBF, but it also decreased the Pickering emulsifying ability. At a sulfuric acid concentration of 3 mol/L, appropriate treatment time (2 and 3 days) led to particle aggregation but significantly improved wettability, thereby resulting in a rapid enhancement in emulsifying capacity. Under these conditions, the obtained HTBF (HTBF-D2-C3 and HTBF-D3-C3) could stabilize medium-chain triglyceride (MCT)-based Pickering high-internal-phase emulsions (HIPEs) with an oil-phase volume fraction of 80% at the addition amounts (c) of ≥1.0% and ≥1.5%, respectively. Its performance was significantly superior to that of TBF (c ≥ 2.0%). Furthermore, at the same addition amount, the droplet size of HIPEs constructed by HTBF-D3-C3 was smaller than that of HTBF-D2-C3, and its gel strength and microrheological performance were also superior to those of HTBF-D2-C3, which was attributed to the higher wettability of HTBF-D3-C3. The findings of this study can facilitate the in-depth application of Tartary buckwheat and provide references for the development of novel Pickering emulsifiers.

17.
Waste Manag ; 184: 20-27, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38788499

RESUMO

Municipal solid waste (MSW) landfill sites have been identified as a significant source of pharmaceuticals in the environment because unused or expired pharmaceuticals are discarded into MSW, which eventually percolate into leachates. However, the contamination of pharmaceuticals in landfill leachate in China is not comprehensively understood. Previous research into factors influencing pharmaceutical concentrations focused on a limited number and type of target pollutants or restricted study area. In the present study, 66 pharmaceuticals were analyzed (including 45 antibiotic and 21 non-antibiotic pharmaceuticals, also categorized as 59 prescription and 7 non-prescription pharmaceuticals) in leachate samples from landfill sites with various characteristics in different regions of China. The results indicated that non-antibiotic pollutants were present at significantly higher concentrations than antibiotic pollutants, with median concentrations of 1.74 µg/L and 527 ng/L, respectively. Non-antibiotic pollutants also presented a higher environmental risk than antibiotic pollutants, by 2 to 4 orders of magnitude, highlighting that non-antibiotic pharmaceuticals should not be overlooked during the assessment of landfill leachate. Pharmaceutical concentrations in landfill leachate samples exhibited regional differences; the population size served by the landfills was the dominant factor contributing to the observed differences. In addition, landfill characteristics such as the solid waste composition and MSW loading can also affect pharmaceutical concentrations in landfill leachate. Despite the implementation of the classification and disposal policy of MSW in Shanghai, China since July 2019, specifying that unused or expired pharmaceuticals should be discarded as hazardous waste, high levels of pharmaceutical contaminations were detected in leachate from the main components of classified MSW (i.e., residual and food waste). These findings emphasize the importance of pharmaceutical management in solid waste systems.


Assuntos
Monitoramento Ambiental , Instalações de Eliminação de Resíduos , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , China , Preparações Farmacêuticas/análise , Eliminação de Resíduos , Resíduos Sólidos/análise
18.
Food Chem X ; 22: 101277, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38515830

RESUMO

The acid-hydrolyzed acorn starch samples (HAS-1, HAS-2, HAS-3, and HAS-4) were prepared from natural acorn starch (NAS) at sulfuric acid concentrations of 1, 2, 3, and 4 mol/L for 2 d. The particle characteristics and structures of HAS were investigated, and Pickering high internal phase emulsions (HIPEs) based on HAS were constructed and characterized. The results showed that with an increase in sulfuric acid concentration, the size, yield, amylose content, molecular weight, and amylopectin chain length of HAS gradually decreased. HAS retained an A-type crystal structure, and its relative crystallinity and short-range order degree gradually increased with increasing sulfuric acid concentration. Acid hydrolysis treatment improved the wettability of NAS, and its effect was positively correlated with the sulfuric acid concentration. HAS-3 and HAS-4 could stabilize the Pickering HIPEs with an oil phase volume fraction of 80% at c ≥ 1.5%. The mechanical properties of the HIPEs were positively correlated with c.

19.
J Hazard Mater ; 473: 134621, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38795494

RESUMO

Neonicotinoids (NEOs) are widely used insecticides and have been detected in aquatic environments globally. However, little is known about NEOs contamination in the coastal environments under the terrestrial pressure of multiple planting types simultaneously. This study investigated the occurrence, spatial-seasonal variability, and ecological risks of NEOs along the coast of the Shandong Peninsula during the dry and wet seasons, where located many largest fruit, vegetable, and grain production bases in China. The concentrations of ∑NEOs in seawater were higher in wet seasons (surface: 195.46 ng/L; bottom: 14.56 ng/L) than in dry seasons (surface: 10.07 ng/L; bottom: 8.45 ng/L). During the wet seasons, NEOs peaked in the northern and eastern areas of the Shandong Peninsula, where the inland fruit planting area is located. While dry seasons had higher concentrations in Laizhou Bay, influenced by rivers from vegetable-growing areas. Grain crops, fruit, and cotton planting were major NEOs sources during wet seasons, while wheat and vegetables dominated in dry seasons. Moderate or above ecological risks appeared at 53.8% of the monitoring sites. Generally, NEOs caused high risks in the wet seasons mainly caused by Imidacloprid, and medium risk in the dry seasons caused by Clothianidin, which should be prevented and controlled in advance.


Assuntos
Agricultura , Monitoramento Ambiental , Inseticidas , Neonicotinoides , Estações do Ano , Água do Mar , Poluentes Químicos da Água , Inseticidas/análise , Inseticidas/toxicidade , Água do Mar/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Neonicotinoides/análise , Neonicotinoides/toxicidade , China , Medição de Risco
20.
Huan Jing Ke Xue ; 45(6): 3165-3175, 2024 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-38897740

RESUMO

To comprehensively assess the pollution characteristics and ecological risks of antibiotics in the rivers in Beijing, the concentrations of 35 common antibiotics belonging to four categories were quantified by using solid phase extraction combined with high-performance liquid chromatography-tandem mass spectrometry. The ecological risks of antibiotics were evaluated using the methods of risk quotient (RQ) and joint probability curves (JPCs). The results showed that a total of 33 antibiotics were detected in the surface water of ten rivers in Beijing, and the total concentrations of antibiotics ranged from N.D. to 1 573.57 ng·L-1. Sulfamethoxazole showed the highest concentration (N.D.-160.04 ng·L-1), followed by sulfadiazine (0.09-147.90 ng·L-1) and ofloxacin (0.28-94.72 ng·L-1). There were 16 antibiotics with a detection frequency greater than 50.0 %. The RQ method showed that there were 12 antibiotics with potential ecological risks. Tetracycline, clarithromycin, and trimethoprim showed the highest risks, with RQs of 3.99, 1.86, and 1.01, respectively. The risks of antibiotics at the outlets of wastewater treatment plants were higher than those in mainstream rivers. The PNEC exceedance rates of tetracycline, clarithromycin, and trimethoprim were above 2.3 %. Based on JPCs, the maximum risk product of clarithromycin was 1.66 %, and it showed low risks to 0.3 %-7.0 % of species. The risks of other antibiotics could be ignored. The detection frequency, distribution of concentrations, most sensitive species, and species sensitivity distribution of antibiotics had important impacts on the ecological risk assessment. Using the multilevel ecological risk assessment strategy can effectively avoid inadequate protection and overprotection and is also conducive to the hierarchical and zoning management of antibiotics throughout the region.


Assuntos
Antibacterianos , Monitoramento Ambiental , Rios , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Rios/química , Medição de Risco , Antibacterianos/análise , Monitoramento Ambiental/métodos , Pequim , China , Cidades , Espectrometria de Massas em Tandem
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