Determination of partition coefficients of phthalic acid esters between polydimethylsiloxane and water and its field application to surface waters

Rishikesh Bajagain; Pil-Gon Kim; Jung-Hwan Kwon; Yongseok Hong

doi:10.1016/j.jhazmat.2023.130933

Determination of partition coefficients of phthalic acid esters between polydimethylsiloxane and water and its field application to surface waters

J Hazard Mater. 2023 Apr 15:448:130933. doi: 10.1016/j.jhazmat.2023.130933. Epub 2023 Feb 1.

Authors

Rishikesh Bajagain¹, Pil-Gon Kim², Jung-Hwan Kwon², Yongseok Hong³

Affiliations

¹ Department of Environmental Engineering, Korea University Sejong Campus, 2511 Sejong-ro, Sejong City, 30019, South Korea.
² Division of Environmental Science and Ecological Engineering, Korea University, Seoul 02841, South Korea.
³ Department of Environmental Engineering, Korea University Sejong Campus, 2511 Sejong-ro, Sejong City, 30019, South Korea. Electronic address: yongseokhong@korea.ac.kr.

PMID: 36860070
DOI: 10.1016/j.jhazmat.2023.130933

Abstract

Phthalic acid esters (PAEs) or phthalates are endocrine-disrupting chemicals and among the most frequently detected hydrophobic organic pollutants, which can be gradually released from consumer products into the environment (e.g., water). This study measured the equilibrium partition coefficients for 10 selected PAEs, with a wide range of logarithms of the octanol-water partition coefficient (log K_ow) from 1.60 to 9.37, between poly(dimethylsiloxane) (PDMS) and water (K_PDMSw) using the kinetic permeation method. The desorption rate constant (k_d) and K_PDMSw for each PAEs were calculated from kinetic data. The experimental log K_PDMSw for the PAEs ranges from 0.8 to 5.9, which is linearly correlated with log K_ow values up to 8 from the literature (R² > 0.94); however, it slightly deviated for the PAEs with log K_ow values greater than 8. In addition, K_PDMSw decreased with the temperature and enthalpy for PAEs partitioning in PDMS-water in an exothermic manner. Furthermore, the effects of dissolved organic matter and ionic strength on the partitioning of PAEs in PDMS were investigated. PDMS was used as a passive sampler to determine the aqueous concentration of plasticizers in river surface water. The results of this study can be used to evaluate the bioavailability and risk of phthalates in real environmental samples.

Keywords: Kinetic permeation method; PDMS-water partition coefficient; Passive sampling; Phthalates.