Biocide emissions from building materials during wet weather: identification of substances, mechanism of release and transfer to the aquatic environment

Abstract

Biocides are added to or applied on building materials to prevent microorganisms from growing on their surface or to treat them. They are leached into building runoff and contribute to diffuse contamination of receiving waters. This review aimed at summarizing the current state of knowledge concerning the impact of biocides from buildings on the aquatic environment. The objectives were (i) to assess the key parameters influencing the leaching of biocides and to quantify their emission from buildings; (ii) to determine the different pathways from urban sources into receiving waters; and (iii) to assess the associated environmental risk. Based on consumption data and leaching studies, a list of substances to monitor in receiving water was established. Literature review of their concentrations in the urban water cycle showed evidences of contamination and risk for aquatic life, which should put them into consideration for inclusion to European or international monitoring programs. However, some biocide concentration data in urban and receiving waters is still missing to fully assess their environmental risk, especially for isothiazolinones, iodopropynyl carbamate, zinc pyrithione and quaternary ammonium compounds, and little is known about their transformation products. Although some models supported by actual data were developed to extrapolate emissions on larger scales (watershed or city scales), they are not sufficient to prioritize the pathways of biocides from urban sources into receiving waters during both dry and wet weathers. Our review highlights the need to reduce emissions and limit their transfer into rivers, and reports several solutions to address these issues.

Determination of 18 Biocides in Both the Dissolved and Particulate Fractions of Urban and Surface Waters by HPLC-MS/MS

“…In recent years, biocidal substances in the aquatic environment have received an increasing attention because of (i) their many uses especially in urban areas (Bester et al 2008;Bollmann et al 2014b;Paijens et al 2020;Wieck et al 2018), (ii) their transfer into the aquatic environment via wastewater or stormwater discharges (Bollmann et al 2014a;Burkhardt et al 2011;Juksu et al 2019;Wicke et al 2015), and (iii) their negative effect on aquatic organisms (Mohr et al 2008;Vermeirssen et al 2018). Indeed, biocides are toxic and may cause long-term adverse effects to aquatic ecosystems even at low concentrations, such as endocrine disruption in zebrafish larvae (Jiang et al, 2015) or behavioural disturbance in zebrafish embryos (Andrade et al, 2016).…”

“…This work focuses on 18 biocides, which were previously prioritized (Paijens et al 2019) according to (i) their use in urban areas, and especially as preservatives in building materials such as paints, renders, wood or bitumen membranes, (ii) their emission into runoff and the receiving waters, and (iii) their risk for aquatic organisms: diuron, isoproturon, methylisothiazolinone (MIT), benzisothiazolinone (BIT), chloromethylisothiazolinone (CMIT), octylisothiazolinone (OIT), dichloro-octylisothiazolinone (DCOIT), benzalkonium compounds (BZK C12-C16), terbutryn, cybutryn (irgarol 1051), terbuthylazine, carbendazim, iodopropynyl butylcarbamate (IPBC), thiabendazole, tebuconazole and mecoprop. A state-of-the-art review (Paijens et al 2020) identified many knowledge gaps, preventing the full assessment of the risks associated with biocides originating from buildings. Most of these biocides are also used as plant protection products and thus have been monitored in rural areas but more rarely in urban waters (Paijens et al 2020).…”

“…A state-of-the-art review (Paijens et al 2020) identified many knowledge gaps, preventing the full assessment of the risks associated with biocides originating from buildings. Most of these biocides are also used as plant protection products and thus have been monitored in rural areas but more rarely in urban waters (Paijens et al 2020). For other compounds not used as pesticides (isothiazolinones, benzalkonium compounds, IPBC), data in receiving and urban waters are scarcer (Paijens et al 2020).…”

Urban pathways of biocides towards surface waters during dry and wet weathers: Assessment at the Paris conurbation scale

“…A similar approach was carried out to estimate the concentrations of biocides in raw stormwater -not sampled in the present study -from the acquired data in CSOs (wet weather) and WWTP influents (dry weather), both coming from comparable watersheds. Dilution between stormwater and wastewater is assumed to be the prevailing process during biocide transport in sewers, which may be acceptable since the transfer time in the sewer system (several hours) is lower than the typical values of biocide half-lives (several days), so degradation may be neglected [6]. Thus, an analogous relationship to equation 4 may be proposed for biocide concentrations, leading to equation 5. iv.…”

“…However, despite recent progress in conventional treatments, wastewater treatment plants (WWTPs) seem to be still unsuitable for these substances [2][3][4][5]. Biocides are also widely used in building materials (paints, renders, tiles, wood, bitumen membranes) to prevent the growth of microorganisms, such as mosses, fungi, bacteria, algae and lichens, on their surfaces [6]. In order to have the intended effect on microorganisms, they are meant to move within the material during wet weather and to migrate from the deeper layer to the surface of the coating [7].…”