Biocides are incorporated into building surface materials to protect them against algae and fungi growth. When such treated surfaces are exposed to precipitation, they may release these biocides, contaminating receiving water bodies. To regulate the use of biocidal products in line with the European Biocidal Products Regulation it is crucial to identify the precise origin of this type of pollutant. In this study, the leaching of a wide range of biocides and chemical elements from 15 materials was investigated through a laboratory scale experiment. The experimental setup was based on the standard method, SIS-CEN/TS 16637-2:2015. The materials tested included bitumen roofing felt and shingles, impregnated wood, as well as paints intended for concrete, wood, and metal surfaces. Each material was tested in duplicates. All materials were tested at a liquid volume to surface area ratio (L/A) of 22.5 L/m2. Sampling was carried out at three intervals: 6 h, 18 h, and 5 days with the leachant being renewed after each leaching step. The results were that diuron was the most commonly detected biocide from the materials tested. The largest number of biocides, including diuron and its degradation products 1-(3.4-dichlorophenyl) urea (DCPU) and diuron desdimethyl (DCPMU), terbutryn, carbendazim and monuron, were detected in the wood paints. Diuron was detected in all three types of wood paint with a mean areal release ratio of 64.6, 25800, and 5710 μg/m2 for the respective paints. Copper was detected in all leachates from impregnated wood, with mean concentrations of 687, 648, 1450, and 279 μg/L from the four tested wood types, respectively. Some of the biocides released were not reported on the data sheets of the tested materials, indicating a need to investigate broader than only based on the information provided by the manufacturers. Future use of biocides in building surface materials may change due to regulations, phase outs and introduction of new biocides, indicating that source identifications is a continuing effort.

Denna rapport presenterar resultat av ekotoxikologiska tester av avrinning från sju exteriöra byggnadsmaterial. De material som ingick i studien var sådana som är vanligt förekommande på tak och fasader,eller andra ytor i den urbana miljön och omfattande följande sju material: metallplåtar av koppar, zink,galvaniserad stål samt rostfritt stål; bitumenbaserat takpapp samt takduk av PVC från två olika tillverkare. För att analysera toxiciteten samlades avrinning upp vid en befintlig försöksuppställning på campus vidLuleå tekniska universitet vid tre olika regntillfällen. Toxikologiska tester utfördes på tre olika tesorganismer:grönalgen Pseudokirchneriella subcapitata, kräftdjuret Daphnia magna, samt ägg från zebrafisk Danio rerio.

Toxiska effekter observerades på samtliga tre testorganismer som ingick i studien. Avrinning från kopparplåtbedömdes ha en stark toxisk effekt på samtliga tre testorganismer. För tillväxten hos grönalg hadeäven zinkplåt samt galvaniserat stål en starkt toxisk effekt. Hos kräftdjuret Daphnia magna samt ägg frånzebrafisk var det, utöver kopparplåt, ett av PVC-materialen, zinkplåt och galvaniserat stål som uppvisade högst toxisk effekt. Denna kunskap skulle kunna ligga till grund för uppströmsarbete och minimering avnegativa effekter i recipienter på grund av ämnen urlakade från byggnadsmaterial.

Biocider tillsätts exteriöra byggnadsmaterial och ytbehandlingar för att förhindra påväxt av mikroorganismer såsom mossor, svampar, bakterier, alger och lavar som bryter ner materialet, samt för att konservera till exempel tak- och fasadfärg innan applicering. Urlakning av biocider från dessa ytor kan ske vid regn och riskerar att transporteras via dagvatten från den urbana miljön till omkringliggande vattenförekomster. Det övergripande syftet med denna studie var att genom laboratorieförsök jämföra biocidurlakning från olika ytbehandlingar och material som används på tak, fasader eller andra ytor i den urbana miljön, samt att uppskatta vilka av de studerade materialen som är troliga källor tillbiocider i dagvatten. De testade materialen inkluderade två typer av bitumenmembran (takpapp och shingel) från två tillverkare vardera, fyra impregnerade trä och olika typer av färger avsedda för trä- (tre stycken), plåt- (två stycken) och betong-/putsytor (två stycken). Dessa material undersöktes genom lakningsförsök i laboratorium med tre tidsintervall som utfördes i följd efter varandra. Resultaten visade att diuron var den biocid som frigjordes från flest av de testade materialen. Färger för träfasader och betong urlakade högst koncentrationer av biocider bland de testade materialen. Bitumenshingel var det enda testade materialet som inte urlakade några biocider. Dessutom frigjorde impregnerat trä högst koncentrationer av koppar och ett bitumenbaserat papptak samt betong- och plåtfärger släppte de högsta fosforkoncentrationerna. Det finns därmed en potentiell risk för frisättning av biocider från exteriöra byggnadsmaterial och beläggningar på byggnader till avrinning för vidare transport med dagvatten till närliggande vattenförekomster.

Urban runoff is recognised to contribute to the deterioration of surface water quality and previous research pointed out a need to focus on organic micropollutants. This study presents measurements of stormwater quality with respect to polycyclic aromatic hydrocarbons, oil, phthalates, alkylphenols, organotin compounds (OTC), polyfluoroalkyl substances (PFAS) and polychlorinated biphenyls (PCBs) from three Swedish catchments (two industrial parks and one parking lot). The results showed that all the studied groups of organic micropollutants except for PFAS and PCBs were present in the stormwater. The oil levels were similar in base flow compared to runoff, while other substances had higher concentrations during runoff events compared to base flow. Among the analysed phthalates, DEHP and DINP were those that were detected in concentrations above the analytical reporting limits, of which DINP was the most abundant, with a maximum concentration of 140 μg/L. Among the OTCs, monobutyltin was the most abundant, which was detected in all samples and present in the highest concentrations (up to 270 ng/L). Regarding the different types of runoff studied (rain, snowmelt and rain on snow) no clear differences could be identified by the available body of data.

Il est reconnu que le ruissellement urbain contribue à la détérioration de la qualité des eaux de surface et des recherches antérieures ont souligné la nécessité de se concentrer sur les micropolluants organiques. Cette étude présente des mesures de la qualité des eaux pluviales en ce qui concerne les hydrocarbures aromatiques polycycliques, les huiles, les phtalates, les alkylphénols, les composés organostanniques (OTC), les substances polyfluoroalkyles (PFAS) et les polychlorobiphényles (PCB) de trois bassins versants suédois (deux parcs industriels et un parking). Les résultats ont montré que tous les groupes de micropolluants organiques étudiés, à l'exception des PFAS et des PCB, étaient présents dans les eaux pluviales. Les niveaux d'huile étaient similaires dans le flux de base par rapport au ruissellement, tandis que d'autres substances avaient des concentrations plus élevées pendant les événements de ruissellement par rapport au flux de base. Parmi les phtalates analysés, le DEHP et le DINP sont ceux qui ont été détectés à des concentrations supérieures aux limites de déclaration analytique, le DINP étant le plus abondant. Parmi les OTCs, le monobutylétain était le plus abondant, il a été détecté dans tous les échantillons et présent dans les concentrations les plus élevées. En ce qui concerne les différents types de ruissellement étudiés (pluie, fonte des neiges et pluie sur la neige), aucune différence claire n'a pu être identifiée par l'ensemble des données disponibles.

Building surface materials, exposed to wash-off by rainwater or snowmelt, are recognised as one of the significant urban diffuse pollution sources contributing to the impairment of stormwater quality. The pollution conveyed by roof runoff originates from two potential sources, migration of surface material constituents, or wash-off of pollutants deposited on the surface by atmospheric deposition. This study investigated the releases of metals and several groups of contaminants of emerging concern: alkylphenols, alkylphenol ethoxylates, and phthalates, from commercially available materials, which are commonly used on buildings and structure surfaces in the urban environment. The materials tested included the following: metal sheets of stainless steel, copper, zinc, galvanised steel, corten steel, corrugated and coated steel, coated zinc; and bitumen-based roofing felt and shingles, as well as polyvinyl chloride (PVC) from two manufacturers. The stainless steel was considered a control material serving to estimate pollutant contributions deposited on the pilot panels from the surrounding environment. Moreover, this study presents novel data on roof snowmelt induced runoff quality, not reported in the previous literature. The experimental setup consisted of 2-m2 rectangular panels mounted in triplicates of each material and placed in an open-air setting on the campus of Luleå University of Technology, Sweden. Runoff leaving the gently sloping material panels was collected during 11 rain and three snowmelt driven runoff events occurring over a five-year period. The results showed that, in general, the micropollutant concentrations and loads were lower in snowmelt than rain induced runoff, and no decreasing trend was detected in the releases of phthalates or metals during the study period. Moreover, on a yearly basis, copper sheets were estimated to release 0.6 g/m2 Cu to runoff, zinc and galvanised sheets 1.3 and 0.7 g/m2 Zn, respectively, and, PVC sheets were estimated to release up to 78 mg/m2 of diisononyl phthalate (DINP).

Synthetic stormwater was tested to determine the ageing effects on dissolved metal concentrations and used in a column experiment to determine efficiency of four different filter materials (milkweed, bark, peat, polypropylene) in removing total and dissolved metals. Synthetic stormwater was created by adding metal salts, oil and collected stormwater sediment to tap water. Two ageing experiments were performed to determine the change of synthetic stormwater quality over time. One experiment lasted for 11 days and another focused on rapid concentration changes one day after preparation. The one-day ageing experiment showed rapid decrease in dissolved concentration of certain metals, specifically Cu. To consider this change, correction coefficients for each metal were developed and used to estimate the average dissolved metal concentration in the synthetic stormwater during the experiment to determine filter treatment efficiency. During the 11-day experiment on metal concentrations, no noticeable quality changes were observed for at least six days after the preparation of synthetic stormwater. Furthermore, a column experiment was run with duplicate filter columns. Inflow and outflow samples were analysed for total and dissolved metals, turbidity, particle size distribution, and pH. High removal of total metal concentrations was noticed in all tested filter media (58-94%). Dissolved metal concentration removal varied among different filter media. In general, columns with bark and peat media were able to treat dissolved metals better than polypropylene and milkweed. The level of treatment of dissolved metals between the different filter media columns were bark > peat > milkweed > polypropylene.

Urban runoff is a significant pathway for the transport of diverse substances from the urban environment to receiving water bodies. Many of these substances are pollutants of environmental concern with potentially harmful effects on aquatic life. Detailed knowledge of the sources of pollutants entering stormwater runoff is needed to mitigate these effects.The overall aim of this doctoral thesis is therefore to provide new knowledge on the sources contributing to urban runoff pollution and to evaluate the specific contributions of micropollutants from two known major sources: building and structure surface materials, and vehicular activities. The work presented herein also (i) identifies pollutants that are expected to occur in runoff from buildings and other structure surfaces in the urban environment as well as in runoff from the road environment, (ii) estimates the concentrations of these pollutants released into runoff, and (iii) evaluates methods for identifying sources contributing to the pollution of urban stormwater runoff.

The novel work presented in the thesis includes a critical review of the literature on sources contributing to urban runoff pollution, laboratory leaching tests and open-air sampling of pilot panels of building and structure surface materials, and field sampling of urban roadside snow. The literature review was not restricted in terms of type of pollution, while the experiments focused on selected metals and organic micropollutants including phthalates, alkylphenols, bisphenol A, and polycyclic aromatic hydrocarbons (PAHs).

According to the literature review, atmospheric deposition, vehicular activities, and metallic building envelopes are the major pollution sources in the urban environment and have been studied far more extensively than other sources. Moreover, their dominance is likely to continue given their central roles in urban environments. The experimental results confirmed that vehicular activities were sources of octylphenols, bisphenol A, and phthalates as well as the metal(loid)s Sb and W, both of which were rarely determined in previous studies on urban runoff. Building and structure surface materials such as copper sheets, zinc sheets, and polyvinyl chloride (PVC) roofing membranes were found to release Cu, Zn, nonylphenols, and phthalates. Among alkylphenols, nonylphenols were predominantly found in building surface runoff while octylphenols occurred predominantly in roadside snow. Metals occurred more commonly in dissolved (<0.45 μm) form in building surface runoff than in roadside snow, where metals were mainly attached to particles.

A comparison of methods for identifying building surface materials contributing to runoff pollution showed that laboratory leaching tests were generally effective for source identification but not for estimating concentrations in actual runoff, whereas open-air pilot studies were resource-intensive but give results that agree well with analyses of real runoff. In addition, the release of pollutants from building surface materials subjected to in-situ ageing was investigated and the water quality of rainwater-induced runoff was compared to that of snowmelt-induced runoff; neither of these issues were adequately addressed in the previous literature. These studies showed that pollutant concentrations were generally higher in rain runoff than in snowmelt runoff and that pollutant releases from most materials and substances exhibited no decreasing or increasing trend over time. However, the release of nonylphenols from one of the PVCs did decrease over time, possibly because of washing out and material ageing.

Stormwater and snowmelt runoff is known to contribute to the deterioration of quality of urban surface waters. Vehicular traffic is recognised as a major source of a wide range of pollutants to urban runoff, including conventional pollutants, such as suspended solids and metals, and those referred to as ‘contaminants of emerging concern’. The aim of this study was to investigate the contribution of selected metal(loid)s (Cd, Cr, Cu, Ni, Pb, Pd, Sb, W, Zn), polycyclic aromatic hydrocarbons (PAHs), nonylphenols, octylphenols and –ethoxylates, phthalates and bisphenol A (BPA) from vehicular traffic by sampling urban roadside snow at eight sites, with varying traffic intensities, and one control site without direct impacts of traffic. Our results confirmed that vehicles and traffic-related activities were the sources of octylphenols, BPA and phthalates as well as the metal(loid)s Sb and W, infrequently reported in previous studies. Among metal(loid)s, Cu, Zn and W occurred in the highest concentrations (up to 1.2 mg/L Cu, 2.4 mg/L Zn and 1.9 mg/L W), while PAHs and phthalates occurred in the highest concentrations among the trace organic pollutants (up to 540 μg/L phthalate diisononyl phthalate). Among the phthalates, di-(2-ethylhexyl)phthalate had the highest frequency of detection (43% of the roadside samples). While BPA and octylphenols had relatively high frequencies of detection (50% for BPA and 81% for octylphenols), they were present in comparatively low concentrations (up to 0.2 μg/L BPA and 1.1 μg/L octylphenols). The control site displayed generally low concentrations of the pollutants studied, indicating that atmospheric deposition was not a significant source of the pollutants found in the roadside snow. Several of the pollutants in the roadside snow exceeded the applicable surface water and stormwater effluent guideline values. Thus, the transport of these pollutants with runoff posed risk of causing adverse effects in the receiving surface waters.

Byggnadsmaterial som används på exteriöra ytor såsom tak, fasader, vägräcken och andra strukturer in den urbana miljön är kända som en av de största källorna till föroreningar i dagvatten. I denna studie har bidraget av metaller och organiska föroreningar till avrinning från 10 stycken vanligt förekommande byggnadsmaterial undersökts genom provtagning av avrinning vid regn och snösmältning från pilotpaneler av de olika materialen i utomhusmiljö. Resultaten visade att flera av de testade materialen bidrog med föroreningar såsom metallerna koppar och zink samt de organiska föroreningarna ftalater och alkylfenoler som riskerar att orsaka negativa effekter för vattenlevande organismer.