title: Estimating safe concentrations of trace metals from inter-continental field data on river macroinvertebrates.
abstract: We derived safe concentrations (SCs) of copper, zinc, cadmium, and manganese using river macroinvertebrate surveys at over 400 individual sites on three continents represented by the UK, USA, and Japan. We related a standardized measure of EPT (Ephemeroptera, Plecoptera, and Trichoptera) taxon richness to dissolved metal concentrations and identified SCs as the thresholds at which effects became apparent. Estimated SCs (and 95% confidence interval, μg/L) for copper, zinc, cadmium, and manganese were 6.6 (1.2-14.2), 34 (11-307), 0.11 (0.06-0.49), and 7.1 (1.4-20.5), respectively. These values for copper, zinc, and cadmium overlapped closely with laboratory-derived SCs available from water quality criteria/standards in the USA/UK and also predicted no effect concentrations from European Union risk assessments. Such laboratory-derived SCs for manganese are unavailable. These results not only add considerable confidence to the application of existing metal standards, but illustrate also how standard values might be widely transportable geographically.
authors.affiliation: Department of Civil Engineering, Tokyo Institute of Technology, 2-12-1-M1-4 Ookayama, Meguro-ku, Tokyo 152-8552, Japan. yuichiwsk@gmail.com
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Iwasaki
authors.forename: Steve J
authors.initials: SJ
authors.lastname: Ormerod
mesh_terms: D000818:Animals; D002104:Cadmium / Q000032:analysis / Q000378:metabolism; D003300:Copper / Q000032:analysis / Q000378:metabolism; D004784:Environmental Monitoring; D007448:Invertebrates / Q000378:metabolism*; D007564:Japan; D008345:Manganese / Q000032:analysis / Q000378:metabolism; D008670:Metals / Q000032:analysis / Q000378:metabolism*; D045483:Rivers / Q000737:chemistry*; D006113:United Kingdom; D014481:United States; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000378:metabolism*; D014877:Water Pollution, Chemical / Q000706:statistics & numerical data; D015032:Zinc / Q000032:analysis / Q000378:metabolism
chemical_list: D008670:Metals; D014874:Water Pollutants, Chemical; D002104:Cadmium; D008345:Manganese; D003300:Copper; D015032:Zinc