title: Coal-tar based pavement sealant toxicity to freshwater macroinvertebrates.
abstract: Non-point-source pollution is a major source of ecological impairment in urban stream systems. Recent work suggests that coal-tar pavement sealants, used extensively to protect parking areas, may be contributing a large portion of the polycyclic aromatic hydrocarbon (PAH) loading seen in urban stream sediments. The hypothesis that dried coal-tar pavement sealant flake could alter the macroinvertebrate communities native to streams in Austin, TX was tested using a controlled outdoor laboratory type approach. The treatment groups were: control, low, medium, and high with total PAH concentrations (TPAH = sum of 16 EPA priority pollutant PAHs) of 0.1, 7.5, 18.4, & 300 mg/kg respectively. The low, medium, and high treatments were created via the addition of dried coal-tar pavement sealant to a sterile soil. At the start of the 24-day exposure, sediment from a minimally impacted local reference site containing a community of live sediment-dwelling benthic macroinvertebrates was added to each replicate. An exposure-dependent response was found for several stream health measures and for several individual taxa. There were community differences in abundance (P = 0.0004) and richness (P < 0.0001) between treatments in addition to specific taxa responses, displaying a clear negative relationship with the amount of coal-tar sealant flake. These results support the hypothesis that coal-tar pavement sealants contain bioavailable PAHs that may harm aquatic environments.
authors.affiliation: Texas State University -San Marcos, San Marcos, TX 78666, USA. pamela.bryer@lamar.edu
authors.forename: Pamela J
authors.initials: PJ
authors.lastname: Bryer
authors.forename: Mateo
authors.initials: M
authors.lastname: Scoggins
authors.forename: Nancy L
authors.initials: NL
authors.lastname: McClintock
mesh_terms: D000818:Animals; D003033:Coal Tar / Q000633:toxicity*; D004784:Environmental Monitoring; D005618:Fresh Water / Q000032:analysis; D007448:Invertebrates / Q000187:drug effects*; D011084:Polycyclic Aromatic Hydrocarbons / Q000633:toxicity*; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D011084:Polycyclic Aromatic Hydrocarbons; D014874:Water Pollutants, Chemical; D003033:Coal Tar