title: Toxicity assessment of size-fractionated urban road dust using ostracod Heterocypris incongruens direct contact test.
abstract: Urban road dusts (URDs, n=10) were collected from arterial, residential, parking area in highway and highway roads in and around Tokyo, Japan, to characterize toxicity of size-fractions by the ostracod Heterocypris incongruens direct contact test. The URDs were collected with vacuum cleaner and highway sweeping vehicles, dried and size-fractionated before conducting toxicity test. The LC20 and LC50 of URDs varied (v/v) from 1.6 to 49%, and 3.8 to 67% respectively. Cluster analysis of URDs based on the concentration of heavy metal and PAHs standardized with the organic matter content was able to differentiate URDs into two groups, one group of higher toxicity and the other group of medium and lower toxicity. Mortality of ostracod decreased for some of the URDs when holding time of URD-water mixture was changed from 1h to 24h prior to the toxicity test. Fraction of fine particles was not always more toxic than the other fractions of coarse and medium particles. Site specific differences in toxicity of size-fractionated URDs indicated the complexity in defining URD toxicity as there could be co-existence of various non-targeted toxicants.
authors.affiliation: Department of Urban Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-Ku, Tokyo 113-8656, Japan. Electronic address: khanal@env.t.u-tokyo.ac.jp.
authors.forename: Rajendra
authors.initials: R
authors.lastname: Khanal
authors.affiliation: Research Center for Water Environment Technology, The University of Tokyo, 7-3-1 Hongo, Bunkyo-Ku, Tokyo, 113-8656, Japan. Electronic address: furumai@env.t.u-tokyo.ac.jp.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Furumai
authors.affiliation: Department of Urban Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-Ku, Tokyo 113-8656, Japan. Electronic address: nakajima@env.t.u-tokyo.ac.jp.
authors.forename: Fumiyuki
authors.initials: F
authors.lastname: Nakajima
mesh_terms: D000818:Animals; D002947:Cities; D003445:Crustacea; D004391:Dust / Q000032:analysis*; D018675:Toxicity Tests
chemical_list: D004391:Dust
keywords: Heavy metal; Ostracod; Polycyclic aromatic hydrocarbon; Toxicity; Urban road dust