Issue 11, 2021

Precipitation-induced transport and phase partitioning of organophosphate esters (OPEs) in urban and rural watersheds

Abstract

Organophosphate esters (OPEs) are extensively used as additives in industrial and consumer products as flame retardants, lubricants, and plasticizers. Such widespread occurrence coupled with precipitation-generated runoff can result in their transport from the atmosphere and terrestrial surfaces into water bodies. Using streamflow samples collected at high temporal resolution from two rivers in the Greater Toronto Area, Canada, we assessed the occurrence, distribution, transport, and likely sources of nine OPEs, covering a wide hydrophobicity range. Chlorinated OPEs (tris(2-chloroethyl) phosphate (TCEP), tris(1-chloro-2-propyl) phosphate (TCIPP) and tris(1,3-dichloro-2-propyl) phosphate (TDCPP)) were prevalent, making up 61% and 68% of total OPEs in the urban and rural rivers, respectively. OPE enrichment at high flow was observed at the outlet of the urban river, primarily due to precipitation-induced transport of particle bound OPEs. OPEs in the low log KOW range like triethyl phosphate (TEP) and TCEP dominated the dissolved phase, while high log KOW compounds like triphenyl phosphate (TPHP) and tris(2-ethylhexyl) phosphate (TEHP) were mostly adsorbed to particles. For OPEs that were sufficiently detected in both phases, calculated organic carbon–water distribution constants (Image ID:d1ew00329a-t2.gif) were found to mostly be higher than values predicted using poly-parameter linear free energy relationships (ppLFERs), the open structure–activity/property relationship application (OPERA) and KOCWIN. Predictions made using EPISuite's molecular connectivity index (MCI) method and COSMOtherm were found to be closer to measured values. Particle bound OPEs can (i) sometimes occur at proportions higher than expected based on predicted equilibrium behavior and (ii) be major determinants of OPE occurrence and transport in urban aquatic environments during storm run-off.

Graphical abstract: Precipitation-induced transport and phase partitioning of organophosphate esters (OPEs) in urban and rural watersheds

Supplementary files

Article information

Article type
Paper
Submitted
12 May 2021
Accepted
20 Sep 2021
First published
04 Oct 2021
This article is Open Access
Creative Commons BY-NC license

Environ. Sci.: Water Res. Technol., 2021,7, 2106-2115

Precipitation-induced transport and phase partitioning of organophosphate esters (OPEs) in urban and rural watersheds

B. Awonaike, Y. D. Lei and F. Wania, Environ. Sci.: Water Res. Technol., 2021, 7, 2106 DOI: 10.1039/D1EW00329A

This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. You can use material from this article in other publications, without requesting further permission from the RSC, provided that the correct acknowledgement is given and it is not used for commercial purposes.

To request permission to reproduce material from this article in a commercial publication, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party commercial publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements