Estimation of n-octanol/water partition coefficients (Kow) of all PCB congeners by density functional theory

Zhou, Wen; Zhai, Zhicai; Wang, Zunyao; Wang, Liansheng

doi:10.1016/j.theochem.2005.08.020

Cited by 67 publications

(52 citation statements)

References 21 publications

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“…The pentaPCBs and hexa-PCBs had the higher BSAF values. In view of the lipophilic property of PCBs, the relationship between BSAF values and K OW values [24] was explored. It was found that BSAF values of PCBs for mitten-handed crabs and loaches both exponentially increased with the increase of K OW values from 5.6 to 6.8 ( Figure 4).…”

Section: Bioaccumulation Of Pcbsmentioning

confidence: 99%

Irrigation-induced pollution of organochlorine pesticides and polychlorinated biphenyls in paddy field ecosystem of Liaohe River Plain, China

Man

Zhang

et al. 2013

Chin. Sci. Bull.

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In order to assess the influence of long-term irrigation of polluted river water on the ecological health of the rice fields in the low reach of Liaohe River Plain, a series of environmental samples and biological samples in rice fields, including sediments, paddy soils, mitten-handed crabs (Eriocheir sinensis), loaches (Misgurnus anguillicaudatu) and frog (Hoplobatrachus tigerinus), were collected from the area far away from industrial zones, and polychlorinated biphenyls (PCBs) and organochlorine pesticides (HCH, DDT, HCB and Mirex) were analyzed by high resolution gas chromatography coupled with high resolution mass spectrometry (HRGC/HRMS). The comparison of pollutant concentrations and profiles verified that the significant contribution of river water irrigation to PCBs contaminations in paddy soils and the mutual influence of organochlorine pesticide contamination between river sediments and paddy soils. Bioaccumulations of PCBs and organochlorine pesticides in mitten-handed crabs and loaches were site-specific, suggested that they were both the good indicators of ecosystem health. Mitten-handed crabs had the highest capacity to accumulate PCBs and organochlorine pesticides, and also they had the strong ability to degrade these pollutants in their bodies, especially for DDT and HCH. The biota-soil accumulation factors (BSAF) of HCH, DDT, Mirex, HCB Σ Σ and PCB Σ s in mitten-handed crab were calculated to be 24.5, 15.3, 122.2, 28.1 and 54.6, respectively. In view of the strong bioaccumulation ability, the health risk should be concerned for the cultivation of mitten-handed crabs in paddy fields in the low reach of Liaohe River Plain.

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Section: Bioaccumulation Of Pcbsmentioning

confidence: 99%

Irrigation-induced pollution of organochlorine pesticides and polychlorinated biphenyls in paddy field ecosystem of Liaohe River Plain, China

Man

Zhang

et al. 2013

Chin. Sci. Bull.

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“…Meanwhile the Hyperchem output files again were used by the Gaussian 98, 43 program to calculate 2 classes of descriptor including: electrostatic (minimum and maximum of partial charge, polarity parameters, charge surface area descriptors, etc) and quantum chemical (dipole moment, HOMO and LUMO energies, etc) was operated to optimized with 6-31 + G ** basis set for all atoms at the B3LYP level. 44,45 No molecular symmetry constrain was applied rather full optimization of all bond lengths and angles was carried out at the level B3LYP/6-31 ++ G **…”

Section: Descriptor Generation and Screeningmentioning

confidence: 99%

QSPR study of partition coefficient (Ko/w) of some organic compounds using radial basic function-partial least square (RBF-PLS)

Goudarzi¹,

Goodarzi²

2010

J. Braz. Chem. Soc.

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Neste trabalho, nós introduzimos um novo método da função de base radial por regressão de mínimos quadrados (RBF-PLS) com elevada exatidão e precisão nos estudos quantitativos da relação entre a estrutura-propriedade de compostos orgânicos (QSPR). Três métodos QSPR foram comparados para a predição dos coeficientes de partição no sistema n-octanol-água (K o/w ) (de alguns compostos orgânicos). A regressão linear múltipla (MLR), a regressão parcial dos mínimos quadrados (PLS) e a regressão base radial com funções pelo método de mínimos quadrados (RBF-PLS) foram empregadas para construir os modelos lineares e não-lineares e predizer o valor de K o/w . Os descritores teóricos foram calculados por Dragon e por Gaussian 98 e foram explorados pelas regressões parciais, codificando diferentes aspectos topológicos, geométricos e eletrônicos das estruturas moleculares. A raiz quadrada dos erros médios previstos (RMSEP) para as etapas de testes e da previsão teórica por modelos de MLR, de PLS e de RBF-PLS foram 0,4022; 0,4128; 0,3050; 0,3564; 0,0364 e 0,0533 respectivamente. Também, o erro padrão relativo previsto (RSEP) para os testes e de previsão teórica por MLR, PLS e RBF-PLS foram de 13,24; 13,60; 10,04; 11,74; 1,197 e 1,757 respectivamente. Os dados mostram que o RBF-PLS produziu resultados melhores do que PLS e MLR.In this work, we introduce a new method ability radial basic function-partial least square (RBF-PLS) with high accuracy and precision in QSPR studies. Three quantitative structure-propertty relationship (QSPR) methods have been compared for the prediction of n-octanol-water partition coefficients (K o/w ) of some organic compounds. The multiple linear regressions (MLR), partial least square (PLS) and radial basis function-partial least squares (RBF-PLS) models were employed to construct linear and nonlinear models to predict of K o/w . The theoretical descriptors that calculated by Dragon and Gaussian 98 were explored by stepwise regressions, encoding different aspects of the topological, geometrical and electronic molecular structures. The root means square error of prediction (RMSEP) for training and prediction sets by MLR, PLS and RBF-PLS models were 0.4022, 0.4128, 0.3050, 0.3564, 0.0364 and 0.0533, respectively. Also, the relative standard error of prediction (RSEP) for training and prediction sets by MLR, PLS and RBF-PLS models were 13. 24, 13.60, 10.04, 11.74, 1.197 and 1.757 respectively. The resultant data explained that RBF-PLS produced better results than PLS and MLR.

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“…A large number of calculation methods have been presently developed for estimation of the partition coefficients with varying success and applicability. According to the descriptors used, these methods can be classified into two groups: empirical and theoretical methods [16]. Chu and Chan [17] reported the relationships between soil sorption coefficients (K OC ), water solubility (S), and K OW of a diverse collection of pollutants, use whole word not abbreviation aliphatics, aromatics, pesticides, herbicides and PAHs.…”

Section: Introductionmentioning

confidence: 99%

“…It is however limited by the unavailability of the latter properties for the majority of chemicals of environmental concern [18]. Various studies have shown that parameters such as n-octanol/ air partition coefficients (K OA ), S, K OW and K OC are correlated to some molecular descriptors, which can be calculated directly just from chemical structures without the input of any other experimental data [13,16,[19][20][21][22][23][24][25][26]. Predictive models based on non-experimental molecular descriptors can provide cost effective and rapid estimates of partitioning behavior of contaminants.…”

Section: Introductionmentioning

confidence: 99%

“…Hence, the development of QSPR models in which quantum chemical descriptors are used is of great importance [32,33]. Rapid advancement of modern computational capability and development of fast algorithms allow the high precision method to be expeditiously applied in current QSPR studies [16,25,26,[34][35][36][37][38], several of which are about partitioning properties of environmental pollutants [16,25,26]. Modern theoretical method in quantum chemistry with high calculation precision was proved having its advantages in estimating properties of environmental concern [16,35].…”

Section: Introductionmentioning

confidence: 99%

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Estimation of n-octanol/water partition coefficients of polycyclic aromatic hydrocarbons by quantum chemical descriptors

Tao

Dang

et al. 2008

Open Chemistry

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Quantitative structure-property relationship (QSPR) modeling is a powerful approach for predicting environmental behavior of organic pollutants with their structure descriptors. This study reports an optimal QSPR model for estimating logarithmic n-octanol/water partition coefficients (log K OW ) of polycyclic aromatic hydrocarbons (PAHs). Quantum chemical descriptors computed with density functional theory at B3LYP/6-31G(d) level and partial least squares (PLS) analysis with optimizing procedure were used for generating QSPR models for log K OW of PAHs. The squared correlation coefficient (R 2 ) of the optimal model was 0.990, and the results of crossvalidation test (Q 2 cum =0.976) showed this optimal model had high fitting precision and good predictability. The log K OW values predicted by the optimal model are very close to those observed. The PLS analysis indicated that PAHs with larger electronic spatial extent and lower total energy values tend to be more hydrophobic and lipophilic.© Versita Warsaw and Springer-Verlag Berlin Heidelberg.

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Estimation of n-octanol/water partition coefficients (Kow) of all PCB congeners by density functional theory

Cited by 67 publications

References 21 publications

Irrigation-induced pollution of organochlorine pesticides and polychlorinated biphenyls in paddy field ecosystem of Liaohe River Plain, China

Irrigation-induced pollution of organochlorine pesticides and polychlorinated biphenyls in paddy field ecosystem of Liaohe River Plain, China

QSPR study of partition coefficient (Ko/w) of some organic compounds using radial basic function-partial least square (RBF-PLS)

Estimation of n-octanol/water partition coefficients of polycyclic aromatic hydrocarbons by quantum chemical descriptors

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