title: Bioretention storm water control measures decrease the toxicity of copper roof runoff.
abstract: The present study evaluated the ability of 2 different bioretention storm water control measures (SCMs), planter boxes and swales, to decrease the toxicity of sheet copper (Cu) roofing runoff to Daphnia magna. The present study quantified changes in storm water chemistry as it passed through the bioretention systems and utilized the biotic ligand model (BLM) to assess whether the observed D. magna toxicity could be predicted by variations found in water chemistry. Laboratory toxicity tests were performed using select storm samples with D. magna cultured under low ionic strength conditions that were appropriate for the low ionic strength of the storm water samples being tested. The SCMs decreased toxicity of Cu roof runoff in both the BLM results and the storm water bioassays. Water exiting the SCMs was substantially higher than influent runoff in pH, ions, alkalinity, and dissolved organic carbon and substantially lower in total and dissolved Cu. Daphnids experienced complete mortality in untreated runoff from the Cu roof (the SCM influent); however, for planter and swale effluents, survival averaged 86% and 95%, respectively. The present study demonstrated that conventional bioretention practices, including planter boxes and swales, are capable of decreasing the risk of adverse effects from sheet Cu roof runoff to receiving systems, even before considering dilution of effluents in those receiving systems and associated further reductions in copper bioavailability. Environ Toxicol Chem 2017;36:1680-1688. © 2016 SETAC.
authors.affiliation: Urban Environmental Biogeochemistry Laboratory, Towson University, Towson, Maryland, USA.
authors.forename: William J
authors.initials: WJ
authors.lastname: LaBarre
authors.affiliation: Urban Environmental Biogeochemistry Laboratory, Towson University, Towson, Maryland, USA.
authors.forename: David R
authors.initials: DR
authors.lastname: Ownby
authors.affiliation: Mutch Associates, Ramsey, New Jersey, USA.
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: Rader
authors.affiliation: Urban Environmental Biogeochemistry Laboratory, Towson University, Towson, Maryland, USA.
authors.forename: Steven M
authors.initials: SM
authors.lastname: Lev
authors.affiliation: Urban Environmental Biogeochemistry Laboratory, Towson University, Towson, Maryland, USA.
authors.forename: Ryan E
authors.initials: RE
authors.lastname: Casey
mesh_terms: D000818:Animals; D001682:Biological Availability; D003252:Construction Materials; D003300:Copper / Q000737:chemistry / Q000633:toxicity*; D003621:Daphnia / Q000187:drug effects; D007477:Ions; D008024:Ligands; D010944:Plants; D014867:Water / Q000737:chemistry; D014872:Water Movements; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D007477:Ions; D008024:Ligands; D014874:Water Pollutants, Chemical; D014867:Water; D003300:Copper
keywords: Bioretention; Copper; Roof runoff; Storm water; Toxicity