Sorption Constant of Bisphenol A and Octylphenol Onto Size-Fractioned Dissolved Organic Matter Using a Fluorescence Method

Abstract

Dissolved organic matter (DOM) is a complex and heterogeneous mixture ubiquitously present in aquatic systems. DOM affects octylphenol (OP) and bisphenol A (BPA) distribution, transport, bioavailability, and toxicity. This study investigated OP and BPA sorption constants, log KCOC, with three size-fractioned DOM. The molecular weights of the sized fractions were low molecular weight DOM (LDOM, <1 kDa), middle molecular weight DOM (MDOM, 1–10 kDa), and high molecular weight DOM (HDOM, 10 kDa–0.45 μm). The log KCOC ranged from 5.34 to 6.14 L/kg-C for OP and from 5.59 to 6.04 L/kg-C for BPA. The OP and BPA log KCOC values were insignificantly different (p = 0.37) and had a strong positive correlation (r = 0.85, p < 0.001). The OP and BPA LDOM log KCOC was significantly higher than the HDOM and MDOM log KCOC (p = 0.012 for BPA, p = 0.023 for OP). The average specific ultraviolet absorption (SUVA254) values were 32.0 ± 5.4, 13.8 ± 1.0, and 17.9 ± 2.8 L/mg-C/m for LDOM, MDOM, and HDOM, respectively. The log KCOC values for both OP and BPA had a moderately positive correlation with the SUVA254 values (r = 0.79–0.84, p < 0.002), which suggested the aromatic group content in the DOM had a positive impact on sorption behavior.

Comparative Evaluation of the Polar Organic Chemical Integrative Sampler in Two Types of Validation Systems Simulating Peak Concentration Events

“…Water samples (100 ml) were collected 36 times in 14 days to determine aqueous concentrations of BPA and neonicotinoid pesticides. Considering the concentration of dissolved organic compounds (DOCs; less than 5 mg L –1 ) and the BPA DOC partitioning coefficients (5.59–6.04 L/kg‐C), the effect of the sorption of BPA on DOC can be ignored (Chuang et al, 2021).…”

Insight into the hetero-interactions of 4-nonylphenol with dissolved organic matter: multiple spectroscopic methods, 1H NMR study and principal component analysis

“…12–15 Nevertheless, recent researches observed that lower molecular weight MW-fractionated DOM (<1 kDa) had strong adsorption affinities on bisphenol A, octylphenol and pentachlorobenzene. 16,17 This discrepancy may be attributed to the composition heterogeneity of DOM and non-uniformity of HOCs binding functionalities in DOM. Therefore, understanding the interactions between different MW DOM and NPs under different environmental conditions, particularly the underlying interaction mechanisms, is imperative.…”

“…22 It has been reported as an efficient method to investigate the interaction mechanism between HOCs and fluorescent substances. 11,16,20 However, the binding sites are easily overlooked when exploring interactions. 20 Nuclear magnetic resonance (NMR) can be used to provide specific, molecular-level information involved in the interaction, and it is also applied to investigate those occurring between environmental pollutants and DOM.…”