Adsorption–desorption behavior of the endocrine-disrupting chemical quinestrol in soils

Abstract

Quinestrol (QUN), a synthetic estrogen used as an oral contraceptive or emergency contraceptive component, has been shown to be an endocrine-disrupting chemical. To assess the environmental risk of QUN, batch equilibration experiments were conducted to investigate the adsorption–desorption of QUN in five contrasting soils from different areas of China. The leaching properties were also calculated based on the adsorption and degradation data from our previous study with the same soils. The Freundlich and Langmuir models were applied to the sorption–desorption data to examine the affinity towards QUN of the soils, which had varying physical and chemical properties. The K f and K f des values of QUN in the tested soils ranged from 3.72 to 20.47 mg 1−n L n kg −1 and from 1.26 to 7.8 mg 1−n L n kg −1 , respectively, and Q m ranged from 28.25 to 126.58 mg/kg. The desorption data showed that hysteresis occurred. The K f and K f des values of QUN were positively correlated with the soil total organic carbon (OC) and cation exchange capacity (CEC), and it may be due to the content of TOC and CEC exhibited a positive correlation. A low mobility potential of QUN in soils was predicted and verified the adsorption results by the groundwater ubiquity score (GUS) and retardation factor (R f ).

Comparative adsorptive behaviour of cow dung ash and starch as potential eco-friendly matrices for controlled organophosphorus pesticides delivery

“…Adsorption equilibrium studies involving diazinon and dichlorvos on CDA and starch surface were undertaken by the batch equilibrium method 46 , 47 . The amount of the pesticide adsorbed, q e (mg/g), was calculated on the basis of the principle of mass balance, according to Eq.…”

Eficiência na remoção do hormônio 17--etinilestradiol de um efluente sanitário a partir da utilização de solo vegetado com bambu Barriga de Buda (Bambusa tuldoides cv. ventricosa)

“…Tratamentos 2 mg L -1 2,5 mg L -1 3mg L -1 3,5mg Segundo Guo et al (2020), o solo descoberto, apesar de possuir sozinho alto potencial de remoção do EE2, trará aspectos paisagísticos indesejáveis ao local, pois logo será ocupado por plantas daninhas. Sendo assim, ao aplicar o bambu Barriga de Buda, o caráter paisagístico e decorativo do local é mantido, assim como a eficiência do tratamento, podendo considerar seu papel de suma importância para o sistema.…”

Towards Viable Eco-friendly Matrices for Controlled Pesticide Delivery: Adsorptive Behaviour of Cow Dung Ash and Starch Towards Organophosphorus Pesticides

“…Adsorption equilibrium studies involving diazinon and dichlorvos on CDA and starch surface were undertaken by the batch equilibrium method 45,46 The amount of the pesticide adsorbed, qe (mg/g), was calculated on the basis of the principle of mass balance, according to Equation (1), where C0 and Ce = initial and final (i.e., equilibrium) concentrations (mg/dm 3 ), respectively, of the pesticide in the aqueous phase; v = volume of aqueous solution (dm 3 ); and w = mass of adsorbent (g). The experimental data for the adsorption of diazinon and dichlorvos on CDA and starch at pH 4, 7 and 9 at 27 o C are assembled in Tables S1-S4…”