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1.
Sci Total Environ ; 937: 173481, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-38795983

RESUMO

Various bisphenols (BPs) have been frequently detected in the aquatic environment and coexist in the form of mixtures with potential huge risks. As we all know, food chain is a media by which BPs mixtures and their mixtures probably enter the organisms at different trophic levels due to their environmental persistence. As a result, the concentrations of BPs and their mixtures may continuously magnify to varying degrees, which can produce higher risks to different levels of organisms, and even human health. However, the related researches about mixtures are few due to the complexity of mixtures. So, the ternary BP mixtures were designed by the uniform design ray method using bisphenol A (BPA), bisphenol S (BPS) and bisphenol F (BPF) to investigate their food chain effects including bioconcentration and biomagnification. Here, Chlorella pyrenoidosa (C. pyrenoidosa) and Daphnia magna (D. magna) were selected to construct a food chain. The toxic effects of single BPs and their mixtures were also systematically investigated by the time-dependent microplate toxicity analysis (t-MTA) method. Toxicity interaction within the ternary mixture was analyzed by the concentration addition model (CA) and the deviation from the CA model (dCA). The results show that the C. pyrenoidosa and D. magna had obvious bioconcentration and biomagnification effects on BPs and their mixture. The mixture had the potential to enrich at higher nutrient levels. And BPF had the largest bioconcentration effect (BCF1 = 481.86, BCF2 = 772.02) and biomagnification effect (BMF = 1.6). Three BPs were toxic to C. pyrenoidosa by destroying algal cells and decreasing protein and chlorophyll contents, and their toxicity order was BPF > BPA > BPS. Moreover, their ternary mixture exhibits synergism with time/concentration-dependency. The obtained results are of significant reference value for objectively and accurately assessing the ecological and environmental risks of bisphenol pollutants.


Assuntos
Compostos Benzidrílicos , Daphnia , Cadeia Alimentar , Fenóis , Sulfonas , Poluentes Químicos da Água , Fenóis/toxicidade , Compostos Benzidrílicos/toxicidade , Poluentes Químicos da Água/análise , Animais , Sulfonas/toxicidade , Chlorella/metabolismo , Testes de Toxicidade
2.
Sci Total Environ ; 913: 169380, 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38123081

RESUMO

The widespread prevalence and coexistence of diverse guanidine compounds pose substantial risks of potential toxicity interactions, synergism or antagonism, to environmental organisms. This complexity presents a formidable challenge in assessing the risks associated with various pollutants. Hence, a method that is both accurate and universally applicable for predicting toxicity interactions within mixtures is crucial, given the unimaginable diversity of potential combinations. A toxicity interaction prediction method (TIPM) developed in our past research was employed to predict the toxicity interaction, within guanidine compound mixtures. Here, antagonism were found in the mixtures of three guanidine compounds including chlorhexidine (CHL), metformin (MET), and chlorhexidine digluconate (CDE) by selecting Escherichia coli (E. coli) as the test organism. The antagonism in the mixture was probably due to the competitive binding of all three guanidine compounds to the anionic phosphates of E. coli cell membranes, which eventually lead to cell membrane rupture. Then, a good correlation between toxicity interactions (antagonisms) and components' concentration ratios (pis) within binary mixtures (CHL-MET, CHL-CDE, MET-CDE) was established. Based on the correlation, the TIPM was constructed and accurately predicted the antagonism in the CHL-MET-CDE ternary mixture, which once again proved the accuracy and applicability of the TIPM method. Therefore, TIPM can be suggested to identify or screen rapidly the toxicity interaction within ternary mixtures exerting potentially adverse effects on the environment.


Assuntos
Poluentes Ambientais , Testes de Toxicidade , Guanidina/toxicidade , Poluentes Ambientais/toxicidade , Escherichia coli , Guanidinas
3.
Phys Chem Chem Phys ; 18(10): 7184-9, 2016 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-26887356

RESUMO

Using poly (3,4-ethylene-dioxythiophene): poly(styrenesulfonate) ( PEDOT: PSS) as an effective hole collecting layer, high-efficiency PEDOT: PSS/n-Si hybrid solar cells are fabricated and a power conversion efficiency (PCE) of 12.13% is obtained. After being treated by HNO3 vapor, the PCE value of PEDOT: PSS/n-Si hybrid solar cells enhances from 12.13% to 13.44%. NO2 gas molecules in HNO3 vapor play a significant doping role in raising the PCE of solar cells. As the doping level raises, NO2 would get more electrons from PEDOT and lead to the increase of hole carriers in the films, which improves the polymer film's conductivity and PCE of solar cells.

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