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1.
Cereb Cortex ; 34(7)2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-39073380

RESUMO

Disinhibition, characterized by a loss of dietary control, is a significant risk factor for diet failure and the onset of eating disorders in restrained eaters. This study employs resting-state functional connectivity and structural covariance network analyses to explore the neural associations underlying this behavior. By analyzing functional MRI data from 63 female college students, we found that increased disinhibition correlates with enhanced functional connectivity between the medial orbitofrontal cortex and key components of the inhibition system, particularly within the fronto-parietal network. Moreover, we observed a relationship between the structural covariance of the medial orbitofrontal cortex and the inferior parietal lobule and the severity of disinhibition. Importantly, the functional connectivity between the medial orbitofrontal cortex and the inferior parietal lobule predicts the severity of binge eating symptoms in these individuals. These findings indicate that imbalances in the interaction between the brain's reward and inhibition systems can lead to dietary failures and eating disorders, emphasizing the need for targeted interventions.


Assuntos
Imageamento por Ressonância Magnética , Vias Neurais , Lobo Parietal , Córtex Pré-Frontal , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Adulto Jovem , Lobo Parietal/fisiologia , Lobo Parietal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia , Córtex Pré-Frontal/diagnóstico por imagem , Vias Neurais/fisiologia , Vias Neurais/diagnóstico por imagem , Comportamento Alimentar/fisiologia , Comportamento Alimentar/psicologia , Adulto , Inibição Psicológica , Mapeamento Encefálico/métodos , Adolescente , Transtornos da Alimentação e da Ingestão de Alimentos/diagnóstico por imagem , Transtornos da Alimentação e da Ingestão de Alimentos/fisiopatologia , Transtornos da Alimentação e da Ingestão de Alimentos/psicologia
2.
Biol Lett ; 19(5): 20230005, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37221860

RESUMO

While anthropogenic pollutants are known to be a threat to primates, our understanding of exposure to pollutants in situ and their sub-lethal effects is still limited. We used non-invasive biomonitoring to examine associations between faecal concentrations of 97 chemical pollutants and faecal hormone metabolites of cortisol and oestradiol in four primate species inhabiting Kibale National Park, Uganda (chimpanzees-Pan troglodytes, olive baboons-Papio anubis, red colobus-Piliocolobus tephrosceles and red-tailed monkeys-Cercopithecus ascanius). Across all species (n = 71 samples), results demonstrated positive associations of organochlorine pesticides (OCPs) (ß = 0.143, p = 0.020) and organophosphate esters (ß = 0.112, p = 0.003) with cortisol in adult females. Additionally, we observed positive associations of OCPs (ß = 0.192, p = 0.013) and brominated flame retardants (ß = 0.176, p = 0.004) with cortisol in juveniles. Results suggest that cumulative pesticides and flame retardants are disruptive to endocrine function in these populations, which could have implications for development, metabolism and reproduction. Our study further demonstrates that faeces can be an important, non-invasive matrix for examining pollutant-hormone associations in wild primates and other critical wildlife populations.


Assuntos
Poluentes Ambientais , Retardadores de Chama , Praguicidas , Feminino , Animais , Hidrocortisona , Uganda , Parques Recreativos , Fezes , Pan troglodytes , Primatas
3.
Environ Sci Technol ; 55(6): 3539-3548, 2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33616389

RESUMO

There is very little information on the gas-particle partition and spatial and seasonal variations of current-use pesticides (CUPs) in the Great Lakes basin. The atmospheric concentrations of 36 CUPs were measured in 24 h gas and particle samples collected in 2017 at six sites in the Great Lakes basin. Thirteen individual CUPs were detected at least once in both gas- and particle-phase samples, with chlorothalonil, trifluralin, metolachlor, λ-cyhalothrin, cypermethrin, and chlorpyrifos detected in >50% samples. The gas-particle partitioning analysis suggests that gas-phase chemicals like trifluralin and chlorpyrifos were not influenced by either temperature or relative humidity while particle-phase chemicals like metolachlor were marginally and negatively correlated with relative humidity. Median total CUP concentrations were 339, 238, 84, 33, 60, and 6.0 pg/m3 at Chicago, Cleveland, Sturgeon Point, Point Petre, Sleeping Bear Dunes, and Eagle Harbor, respectively. The concentrations of total CUPs and most individual CUPs were generally higher at the urban sites of Chicago and Cleveland than at the rural/remote sites of Sturgeon Point, Point Petre, Sleeping Bear Dunes, and Eagle Harbor. Chlorothalonil, trifluralin, bifenthrin, and chlorpyrifos were the most abundant individual CUPs among fungicides, herbicides, pyrethroid insecticides, and other insecticides, respectively. The spatio-seasonal variation suggests that fungicides at Sturgeon Point and Sleeping Bear Dunes, with the highest fraction of agricultural land use, were associated with agricultural activities, while pyrethroid insecticides were generally driven by human activities.


Assuntos
Poluentes Atmosféricos , Praguicidas , Poluentes Atmosféricos/análise , Chicago , Monitoramento Ambiental , Humanos , Lagos , Praguicidas/análise , Estações do Ano
4.
Environ Sci Technol ; 54(1): 325-334, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31820947

RESUMO

Exposure to flame retardants (FRs) is associated with adverse effects on human health. Focusing on three FR groups, including polybrominated diphenyl ethers (PBDEs), organophosphate FRs (OPFRs), and novel brominated FRs (nBFRs), we determined the levels of these chemicals in indoor air in homes in rural Central Appalachia using passive air samplers and personal exposures in the residents of these homes using silicone wristbands. We also investigated the relationships between the FR levels in wristbands and the thyroid function. The median total concentrations of PBDEs, OPFRs, and nBFRs were 210, 25 000, and 69 pg/m3 in indoor air, and 49, 670, and 110 ng/g in wristbands, respectively. The most abundant chemicals in both air and wristbands were BDE-47 and -99 among PBDEs, tris[(2R)-1-chloro-2-propyl] phosphate among OPFRs, and 2-ethylhexyl 2,3,4,5-tetrabromobenzoate and bis(2-ethylhexyl) tetrabromophthalate among nBFRs. In gender-specific regression models that were controlled for age and smoking, significant associations were observed between BDE-99, BDE-197, and 2-ethylhexyldiphenyl phosphate (EHDP) and free thyroxine (FT4), between BDE-100 and free triiodothyronine (FT3), and between anti-Dechlorane Plus (DP) and thyroid-stimulating hormone (TSH). In particular, most penta-BDE congeners were significantly or marginally significantly associated with FT4 and FT3 for both females and males. Our results suggest that wristbands can be used as suitable exposure monitors for evaluating human exposure to FRs.


Assuntos
Poluição do Ar em Ambientes Fechados , Retardadores de Chama , Região dos Apalaches , Poeira , Monitoramento Ambiental , Feminino , Éteres Difenil Halogenados , Humanos , Masculino , Organofosfatos , Glândula Tireoide
5.
Environ Sci Technol ; 54(19): 12013-12023, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-32900185

RESUMO

The habitats of wild primates are increasingly threatened by surrounding anthropogenic pressures, but little is known about primate exposure to frequently used chemicals. We applied a novel method to simultaneously measure 21 legacy pesticides (OCPs), 29 current use pesticides (CUPs), 47 halogenated flame retardants (HFRs), and 19 organophosphate flame retardants in feces from baboons in the U.S.A., howler monkeys in Costa Rica, and baboons, chimpanzees, red-tailed monkeys, and red colobus in Uganda. The most abundant chemicals were α-hexachlorocyclohexane (α-HCH), ß-hexachlorocyclohexane (ß-HCH), and hexachlorobenzene among OCPs across all sites, chlorpyrifos among CUPs in Costa Rica and Indiana, decabromodiphenylethane (DBDPE) in Costa Rica and Indiana and 2, 2', 4, 4'-tetrabromodiphenyl ether (BDE-47) in Uganda as HFRs, and tris(2-butoxyethyl) phosphate (TBOEP) as OPFRs across all sites. The detected chemical concentrations were generally higher in red-tailed monkeys and red colobus than in chimpanzees and baboons. Our methods can be used to examine the threat of chemical pollutants to wildlife, which is critical for endangered species where only noninvasive methods can be used.


Assuntos
Retardadores de Chama , Praguicidas , Animais , Monitoramento Ambiental , Fezes/química , Retardadores de Chama/análise , Éteres Difenil Halogenados/análise , Indiana , Organofosfatos , Praguicidas/análise , Primatas , Uganda
6.
Environ Sci Technol ; 53(11): 6171-6181, 2019 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-31081620

RESUMO

Protected areas have developed alongside intensive changes in land use and human settlements in the neighboring landscape. Here, we investigated the occurrence of 21 organochlorine pesticides (OCPs), 14 current use pesticides (CUPs), 47 halogenated flame retardants (HFRs), and 19 organophosphate esters (OPEs) in air around Las Cruces (LC) and La Selva (LS) Biological Stations, Costa Rica, and Kibale National Park (KNP), Uganda using passive air samplers (PAS) with polyurethane foam (PUF) discs (PAS-PUF). Significantly higher concentrations of CUPs were observed around LS, while LC had a higher concentration of OCPs. Land use analysis indicated that LS had a higher fraction of agriculture than LC (33% vs 14%), suggesting the higher CUPs concentration at LS was related to pesticide intensive crops, while higher OCPs concentration at LC may be attributed to the area's long agricultural history characterized by small-scale subsistence farming or long-range transport. In Uganda, CUPs and OCPs were generally lower than in Costa Rica, but high concentrations of HFRs were observed inside KNP, possibly due to human activity at research camps near the protected forest. This is the first study that documented the occurrence of anthropogenic chemicals in the air at protected areas with tropical forests.


Assuntos
Poluentes Atmosféricos , Retardadores de Chama , Praguicidas , Costa Rica , Monitoramento Ambiental , Uganda
7.
Environ Sci Technol ; 52(11): 6177-6186, 2018 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-29762021

RESUMO

The authors analyzed spatial and seasonal variations of current use pesticides (CUPs) levels in the atmospheric particulate phase in the Great Lakes basin. Twenty-four hour air samples were collected at six sites (two urban, two rural, and two remote) in 2015. The concentrations of 15 CUPs, including nine pyrethroid insecticides, four herbicides, one organophosphate insecticide, and one fungicide, were measured. The total CUPs concentrations were higher at the urban sites (0.38-1760 pg/m3) than at the rural and remote sites (0.07-530 pg/m3). The most abundant CUPs were pyrethroid insecticides at the urban sites. The levels of the other CUPs did not vary much among the six sites, except at the most remote site at Eagle Harbor, where the levels were significantly lower. Chlorothalonil was the most frequently detected CUP, which was detected in more than 76% of the samples. The atmospheric concentrations of total pyrethroid insecticides and total herbicides were correlated with local human population and developed land use. Significantly higher concentrations of most CUPs were observed in the warmer months than in the colder months at all sites. In addition to agricultural applications, which occur during the warmer months, the CUPs atmospheric concentrations may also be influenced by nonagricultural activities and the urban development.


Assuntos
Poluentes Atmosféricos , Praguicidas , Monitoramento Ambiental , Great Lakes Region , Humanos , Estações do Ano
8.
Environ Sci Technol ; 51(23): 13834-13841, 2017 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-29096434

RESUMO

Plant uptake and acropetal translocation of polychlorinated biphenyls (PCBs) is a major concern, with many uncertainties, especially when plants are exposed to coexisting PCBs and metals. Studying atropisomer selectivity behavior is a well-proven method for identifying the biotransformation process of chiral PCBs in plants. This study investigated the uptake, translocation, and stereoselectivity of PCB95 and PCB136 (3 µg/L in hydroponics and 200 µg/kg in pot experiment) by monocot corn and dicot sunflower after copper (Cu) exposure (50 µmol/L in hydroponics and 400 mg/kg in pot experiment). Cu exposure led to significantly increased PCBs accumulation in roots and enhanced their acropetal translocation from roots to shoots, attributed to Cu-induced root damage. In the absence of Cu, the first-eluting enantiomer of PCB95 and second-eluting enantiomer of PCB136 were preferentially enriched in the shoots and roots of both the monocot and the dicot, and the enantioselectivity of chiral PCBs was more pronounced in shoots than in roots. Cu exposure significantly reduced the stereoselectivity of PCB95 and PCB136 in the defective root system, implying that PCB95 and PCB136 uptake into roots after Cu exposure changed from active biotransformation to passive diffusion. Our findings suggest that the ecological risk of PCB95 and PCB136 uptake and accumulation in plants is underestimated at sites cocontaminated with metals and PCBs and, for the first time, reveal the mechanism associated with the uptake and biotransformation of chiral PCBs in plants after exposure to both heavy metals and chiral PCBs.


Assuntos
Biotransformação , Cobre , Bifenilos Policlorados , Transporte Biológico , Hidroponia , Raízes de Plantas
9.
Environ Sci Technol ; 50(16): 8623-30, 2016 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-27427439

RESUMO

The recycling of e-waste has attracted significant attention due to emissions of polychlorinated biphenyls (PCBs) and other contaminants into the environment. We measured PCB concentrations in surface soils, air equilibrated with the soil, and air at 1.5-m height using a fugacity sampler in an abandoned electronic waste (e-waste) recycling site in South China. The total concentrations of PCBs in the soils were 39.8-940 ng/g, whereas the concentrations in air equilibrated with the soil and air at 1.5 m height were 487-8280 pg/m(3) and 287-7380 pg/m(3), respectively. The PCB concentrations displayed seasonal variation; they were higher in winter in the soils and higher in summer in the air, indicating that the emission of PCBs from the soil was enhanced during hot seasons for the relatively high temperature or additional sources, especially for low-chlorinated PCBs. We compared two methods (traditional fugacity model and fugacity sampler) for assessing the soil-air partition coefficients (Ksa) and the fugacity fractions of PCBs. The results suggested that the fugacity sampler provided more instructive and practical estimation on Ksa values and trends in air-soil exchange, especially for low-chlorinated PCBs. The abandoned e-waste burning site still acted as a significant source of PCBs many years after the prohibition on open burning.


Assuntos
Poluentes Atmosféricos/análise , Resíduo Eletrônico , Bifenilos Policlorados/análise , Reciclagem , Poluentes do Solo/análise , China , Monitoramento Ambiental
10.
Environ Sci Technol ; 50(2): 856-63, 2016 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-26694851

RESUMO

Cocontamination by heavy metals and persistent organic pollutants (POPs) is ubiquitous in the environment. Fate of POPs within soil/water-plant system is a significant concern and an area where much uncertainty still exists when plants suffered cotoxicity from POPs and metals. This study investigated the fate of polybrominated diphenyl ethers (PBDEs) when copper (Cu) was present within the soil/water-plant system using pot and hydroponic experiments. The presence of Cu was found to induce damage to the root cell membranes of corn (Zea mays L. cv. Nongda 108) with increasing concentration in both shoots and roots. The PBDE congeners BDE209 and BDE47 in shoots were also enhanced with the increasing electrolytic leakage from root, attributed to Cu damage, and the highest shoot BDE209 and BDE47 levels were observed under the highest Cu dosage. In addition, positive correlations were observed between the PBDE content of corn shoots and the electrolytic leakage of corn roots. These results indicated that within a defective root system, more PBDEs will penetrate the roots and are acropetally translocated in the shoots. The potential ecological risk associated with the translocation and accumulation of POPs into plant shoots needs careful reconsideration in media cocontaminated with metals and POPs, whereas often ignored or underestimated in environmental risk assessments.


Assuntos
Cobre/toxicidade , Éteres Difenil Halogenados/metabolismo , Raízes de Plantas/metabolismo , Poluentes do Solo/metabolismo , Zea mays/metabolismo , Cobre/metabolismo , Permeabilidade , Raízes de Plantas/efeitos dos fármacos , Brotos de Planta/metabolismo , Solo , Zea mays/efeitos dos fármacos
11.
Environ Sci Technol ; 49(1): 284-91, 2015 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-25453511

RESUMO

Rice, one of the most widely cultivated crops, has received great attention in contaminant uptake from soil and air, especially for the special approaches used for its cultivation. The dry-wet alternation method can influence the air-soil partitioning of semivolatile organic compounds (SVOCs) in the paddy ecosystem. Here, we modified a fugacity sampler to investigate the air-surface in situ partitioning of ubiquitous polycyclic aromatic hydrocarbons (PAHs) at different growth stages in a suburban paddy field in South China. The canopy of rice can form a closed space, which acts like a chamber that can force the air under the canopy to equilibrate with the field surface. When we compared the fugacities calculated using a fugacity model of the partition coefficients to the measured fugacities, we observed similar trends in the variation, but significantly different values between different growing stages, especially during the flooding stages. However, the measured and calculated fugacity fractions were comparable when uncertainties in our calculations were considered, with the exception of the high molecular weight (HMW) PAHs. The measured fugacity fractions suggested that the HMW PAHs were also closed to equilibrium between the paddy field and atmosphere. The modified fugacity sampler provided a novel way of accurately determining the in situ air-soil partitioning of SVOCs in a wet paddy field.


Assuntos
Poluentes Atmosféricos/química , Ar/análise , Oryza/fisiologia , Hidrocarbonetos Policíclicos Aromáticos/química , Poluentes do Solo/química , Solo/química , China
12.
J Agric Food Chem ; 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39166886

RESUMO

This study investigated the uptake pathways, acropetal translocation, subcellular distribution, and biotransformation of OPEs by rice (Oryza sativa L.) after Cu exposure. The symplastic pathway was noted as the major pathway for the uptake of organophosphate triesters (tri-OPEs) and diesters (di-OPEs) by rice roots. Cu exposure enhanced the accumulation of tri-OPEs in rice roots, and such enhancement was positively correlated with Cu concentrations, attributing to the Cu-induced root damage. The hydrophilic Cl-OPEs in the cell-soluble fraction of rice tissues were enhanced after Cu exposure, while the subcellular distributions of alkyl- and aryl-OPEs were not affected by Cu exposure. Significantly higher biotransformation rates of tri-OPEs to di-OPEs occurred in leaves, followed by those in stems and roots. Our study reveals the mechanisms associated with the uptake, translocation, and biotransformation of various OPEs in rice after Cu exposure, which provides new insights regarding the phytoremediation of soils cocontaminated with heavy metal and OPEs.

13.
Food Chem ; 437(Pt 2): 137917, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-37944391

RESUMO

A novel methodology based on ultrasonic-assisted sequential extraction, dispersive-SPE purification, and single-injection on liquid chromatography-tandem mass spectrometry (LC-MS/MS) is proposed, for the first time, to simultaneously measure 14 tri-OPEs and 9 di-OPEs in plant tissues. The samples were successively ultrasonicated with a mixture of hexane:dichloromethane (1:1, v/v) and 8% acetic acid in acetonitrile for extracting tri- and di-OPEs purified with graphitized carbon black and quantitated on LC-MS/MS at the same time. The recoveries of targeted tri- and di-OPEs in the matrix spike ranged from 66% to 120% and 71% to 110% respectively. The proposed method was validated by processing eight types of common vegetables including spinach (Spinacia oleracea L.), lettuce (Lactuca sativa), carrot (Daucus carota var. sativa Hoffm.), sweet potato (Solanum tuberosum L.), cucumber (Cucumis sativus L.), tomato (Solanum lycopersicum L.), green beans (Phaseolus vulgaris), and cowpeas (Vigna unguiculata), with the recoveries of surrogates ranging from 84% to 98%.


Assuntos
Organofosfatos , Espectrometria de Massas em Tandem , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Organofosfatos/análise , Ésteres/análise , Ultrassom , Lactuca , Extração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão
14.
Environ Sci Pollut Res Int ; 30(29): 74021-74030, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37198367

RESUMO

Recent studies have identified the ability of plants to uptake and translocate organophosphate esters (OPEs) within cells. In response to the increasing interest in OPEs and their occurrence in paddy fields and rice, the current study aimed to present an effective and sensitive GC-MS based methodology for quantitative determination of 11 OPEs with octanol-water coefficients ranging from 1.6 to 10. Rice was sonicated with hexane and dichloromethane, and fractionated on two columns: one consisting of neutral alumina, and neutral silica, and the other consisting of graphitized carbon black. Method precision was validated using spiked rice (n = 30) and procedural blanks (n = 9). The mean recovery of matrix spikes for all target OPEs were within 78-110% with relative standard deviation lower than 25%, with a few exceptions. This method was applied to process the wild rice (O. sativa) in which tri-n-propyl phosphate was the dominant targeted OPE. The recoveries of surrogate standards were 81 ± 17% for d12- tris(2-chloroethyl) phosphate and 95 ± 8.8% for 13C12- triphenyl phosphate. The developed method was further used to examine the recoveries of target OPEs in the subcellular structure of rice tissues, including cell wall, cell organelles, cell water-soluble fractions, and cell residue. Recoveries of most target OPEs were in the range of 50-150%; however, ion enhancement was observed for four OPEs in root and shoot tissues. Hydrophobic OPEs accumulated in the cell wall, cell residue, and cell organelles while chlorinated OPEs mainly distributed in the cell water-soluble fraction. These results provide new insight for the ecological risk assessment of OPEs in an important food staple.


Assuntos
Retardadores de Chama , Oryza , Monitoramento Ambiental/métodos , Retardadores de Chama/análise , Ésteres/análise , Organofosfatos/análise , Fosfatos/análise , Água/análise , China
15.
Sci Total Environ ; 875: 162528, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36894077

RESUMO

Increasing attention on the estimation of bioavailability of organophosphate esters (OPEs) in soil or sediment has urged the development of techniques to measure soil-/sediment-associated porewater concentrations of OPEs. In this study, we investigated the sorption dynamics of 8 OPEs to polyoxymethylene (POM) spanning one order of magnitude of aqueous OPE concentrations and proposed POM-water partitioning coefficients (Kpom/w) for OPEs. The results showed that the Kpom/w values were mainly affected by the hydrophobicity of OPEs. OPEs with high solubility preferentially partitioned into the aqueous phase indicated by the low log Kpom/w values; while lipophilic OPEs were observed to be taken up by POM. The concentration of lipophilic OPEs in the aqueous phase had a strong impact on their sorption dynamics on POM, with higher aqueous concentrations accelerating the sorption dynamics and shortening the time for equilibration. We proposed that the required time to reach equilibration for targeted OPEs should be 42 d. The proposed equilibration time and Kpom/w values were further validated by applying POM to soil artificially contaminated with OPEs to measure OPEs soil-water partitioning coefficients (Ks). The variations of Ks among soil types implied the need to elucidate the effects of soil properties and chemical properties of OPEs on their distribution between soil and water in the future.

16.
Brain Imaging Behav ; 15(4): 2069-2080, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33033984

RESUMO

Numerous studies have shown that restrained eating is not an effective weight loss strategy. Restrained eaters often suppress their desires and thoughts about tasty food, which makes it more difficult to control themselves in subsequent eating behavior. The ego depletion impairs conflict monitoring abilities. Therefore, this study explored the effects of food thoughts suppression on restrained eaters' conflict monitoring. Therefore, this study used functional magnetic resonance imaging (fMRI) methods to explore changes in the activity of brain regions involved in conflict monitoring when restrained eaters choose between high- and low-calorie foods after either suppressing or not suppressing thoughts about food. The results showed that, compared to the control condition, after suppression of such thoughts, restrained eaters chose more high-calorie foods and displayed decreased activity in the dorsal anterior cingulate cortex-an important region in charge of conflict monitoring. At the same time, the functional coupling of the dorsal anterior cingulate cortex and the precuneus increased. Our findings suggest that restrained eaters' suppression of thoughts about tasty food could lead to a decline in their ability to monitor conflicts between current behaviors and goals, which in turn leads to unhealthy eating behavior.


Assuntos
Alimentos , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Ingestão de Alimentos , Comportamento Alimentar , Humanos , Hiperfagia
17.
Environ Pollut ; 284: 117358, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34062434

RESUMO

Neonicotinoid insecticides (NIIs) are extensively used worldwide and frequently detected in the environment. The human and ecological risks associated with the occurrence of NIIs in agricultural zones are of high importance. The present study highlights the regional occurrence and human exposure risks of NIIs in agricultural soil within the Pearl River Delta (PRD), South China. Six neonicotinoids, i.e., imidacloprid, clothianidin, acetamiprid, imidaclothiz, dinotefuran, and flonicamid, were measured in 351 soil samples from Zengcheng, a typical agricultural zone. The soil samples were categorized into three groups based on cultivated plants: vegetables, rice, and fruits. At least one of these neonicotinoid insecticides was detected in 95% of the soil samples. The levels of ∑6NII (range (median)) were 0.26-390 (23), 0.26-280 (6.1), and 0.26-120 (5.0) ng g-1 dry weight in soil samples from vegetable farms, rice paddies, and fruit farms, respectively. Neonicotinoids were detected more frequently and at statistically higher concentrations in vegetable farms than in both rice paddies and fruit farms. This is likely ascribed to higher application frequencies of NIIs in vegetable farms due to higher planting frequencies. The hazard index values for human exposure to NIIs in the agricultural soils were all below 1, suggesting negligible non-cancer risks. The current residual levels of NIIs in the soils could however pose sub-lethal or acute effects to non-target terrestrial organisms such as earthworms. The present study suggests that more information is needed regarding NIIs contamination in soils from agricultural regions of South China to ensure that human and ecological risk from exposure to these compounds can be fully addressed.


Assuntos
Inseticidas , Poluentes do Solo , China , Humanos , Inseticidas/análise , Neonicotinoides/análise , Rios , Solo , Poluentes do Solo/análise
18.
Chemosphere ; 274: 129633, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33529960

RESUMO

The behavior of arsenic (As) in paddy soil is of great interest because rice is an efficient As accumulator, which can result in potential health risks to humans. In this study, we investigated the distribution and translocation of As speciation within the soil-rice system in the presence of Fenton solution (100 µM H2O2 and 100 µM Fe2+). The results showed that the iron plaque concentrations were enhanced either by the addition of Fenton solution or under flooded condition. In addition, total As, As5+, and As3+ concentrations were lower in rice tissues treated with Fenton solution than those without Fenton solution treatments. Therefore the addition of Fenton solution can reduce As speciation accumulation in rice tissue. This study revealed the function of Fenton solution on the fate of As speciation distribution within soil-rice system and the link between iron plaque and As accumulation in rice tissue under flooded and non-flooded conditions.


Assuntos
Arsênio , Oryza , Poluentes do Solo , Arsênio/análise , Humanos , Peróxido de Hidrogênio , Solo , Poluentes do Solo/análise , Água
19.
Environ Int ; 155: 106591, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33933901

RESUMO

Organophosphate esters (OPEs) are normally used as flame retardants, plasticizers and lubricants, but have become environmental pollutants. Because OPEs are normally present alongside heavy metals in soils, the effects of interactions between OPEs and heavy metals on plant uptake of OPEs need to be determined. In this study, we investigated the effects of OPEs chemical structure, plant cultivar and copper (Cu) on the uptake and translocation of OPEs by plants. The bioaccumulation of OPEs varied among plant cultivars. They were preferentially enriched in carrot, with the lowest concentrations observed in maize. OPEs with electron-ring substituents (ER-OPEs) exhibited a higher potential for root uptake than did OPEs with open-chain substituents (OC-OPEs), which could be attributed to the higher sorption of ER-OPEs onto root charged surfaces. This was explained by the stronger noncovalent interactions with the electron-rich structure of ER-OPEs. The presence of Cu slightly reduced the distinct difference in the ability of roots to take up OC-OPEs and ER-OPEs. This was explained by the interactions of Cu ions with the electron-rich structure of ER-OPEs, which suppressed the sorption of ER-OPEs on the root surface. A negative relationship between the logarithms of the translocation factor and octanol-water partition coefficient (Kow) was observed in treatments with either OPEs only or OPEs + Cu, implying the significant role of hydrophobicity in the OPEs acropetal translocation. The results will improve our understanding of the uptake and translocation of OPEs by plant cultivars as well as how the process is affected by the chemical structure of OPEs and Cu, leading to improvements in the ecological risk assessment of OPEs in the food chain.


Assuntos
Cobre , Retardadores de Chama , China , Monitoramento Ambiental , Ésteres , Organofosfatos , Estruturas Vegetais
20.
J Agric Food Chem ; 69(7): 2062-2068, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33555873

RESUMO

Plant uptake and translocation of perfluorooctane sulfonate (PFOS) are critical for food safety and raise major concerns. However, those processes are associated with many undisclosed mechanisms, especially when PFOS coexist with heavy metals. In this study, we investigated the effect of copper (Cu) on PFOS distribution in maize tissues by assessing the PFOS concentration and enantioselectivity. The presence of <100 µmol/L Cu exerted a limited effect on PFOS bioaccumulation, while >100 µmol/L Cu damaged the root cell membrane and increased root permeability, resulting in a higher PFOS concentration in roots. The suppression of acropetal translocation might be attributed to Cu inhibition of carrier proteins. The enantiomer fraction (EF) of 1m-PFOS at <100 µmol/L Cu was higher than that in a commercial product (0.5). Racemic PFOS was detected at >100 µmol/L Cu in roots and the EF variation changed from positive to negative in shoots. These EF results evidenced the existence of a protein-mediated uptake pathway. Besides, this study indicated the challenge of chiral signature application in PFOS source identification, given the effects of heavy metals and plants on PFOS enantioselectivity. The findings provide insight into PFOS bioaccumulation in plants cocontaminated with Cu and will facilitate environmental risk assessment.


Assuntos
Ácidos Alcanossulfônicos , Fluorocarbonos , Cobre , Zea mays
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