A study of 101 organic substances in gully pot sediments accumulated over a one-year period in Stockholm, Sweden

Haoyu Wei; Kelsey Flanagan; Lian Lundy; Tone Merete Muthanna; Maria Viklander

doi:10.1016/j.scitotenv.2023.165028

A study of 101 organic substances in gully pot sediments accumulated over a one-year period in Stockholm, Sweden

Sci Total Environ. 2023 Oct 10:894:165028. doi: 10.1016/j.scitotenv.2023.165028. Epub 2023 Jun 21.

Authors

Haoyu Wei¹, Kelsey Flanagan², Lian Lundy², Tone Merete Muthanna³, Maria Viklander²

Affiliations

¹ Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-97187 Luleå, Sweden. Electronic address: haoyu.wei@ltu.se.
² Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-97187 Luleå, Sweden.
³ Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-97187 Luleå, Sweden; Department of Civil and Environmental Engineering, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway.

PMID: 37353017
DOI: 10.1016/j.scitotenv.2023.165028

Abstract

Stormwater runoff is a key pathway for diffuse pollutants to enter receiving waters. Mitigating measures include pollutant substitution, restricting their release into the urban technosphere and limiting the (re-)mobilisation of substances to minimise their negative impacts on receiving waters. Gully pots (GPs) are one of the most ubiquitous urban drainage infrastructure components, providing both a drainage function and limiting the onward transport of pollutants through in-pot sedimentation processes. In this study, sediments accumulated over a one-year period were collected from 26 GPs in catchments of four land-use types in Stockholm, Sweden. Sediments were analysed for 101 organic substances from eight substance groups (hydrocarbons, polycyclic aromatic hydrocarbons, alkylphenols, polychlorinated biphenyls, phthalates, organotins, per- and polyfluoroalkyl substances and brominated fire retardants) to inform an assessment of their occurrence and net accumulation rates over a typical unit operation period. A total of 63 substances were quantified in at least one GP, with aliphatic hydrocarbons, phthalates and organotins quantified in all GP sediments, highlighting their ubiquitous use. The identification of 14 and 21 organic substances in two pedestrian/bike path GPs emphasise the contribution of non-vehicular sources to diffuse pollutant loads. Significantly higher mass accumulation rates of 4-tert-octylphenol, 4-nonylphenols, formaldehyde, dioctyltin and dibutyltin are identified in commercial catchment GPs suggesting the need to enhance source-tracing and runoff quality-control measures within catchments of this land-use type. Sediments in 25 GPs were identified with at least one substance exceeding toxicology-based threshold values, highlighting the runoff quality-control function of GPs in reducing the potential ecotoxic impacts on recipients.

Keywords: Emerging pollutant; Gully pot; Micropollutant; Urban runoff; Urban water; Xenobiotics.