title: Caddisflies Hydropsyche spp. as biomonitors of trace metal bioavailability thresholds causing disturbance in freshwater stream benthic communities.
abstract: Demonstration of an ecotoxicological effect of raised toxic metal bioavailabilities on benthic macroinvertebrate communities in contaminated freshwater streams typically requires the labour-intensive identification and quantification of such communities before the application of multivariate statistical analysis. A simpler approach is the use of accumulated trace metal concentrations in a metal-resistant biomonitor to define thresholds that indicate the presence of raised trace metal bioavailabilities causing ecotoxicological responses in populations of more metal-sensitive members of the community. We explore further the hypothesis that concentrations of toxic metals in larvae of species of the caddisfly genus Hydropsyche can be used to predict metal-driven ecotoxicological responses in more metal-sensitive mayflies, especially ephemerellid and heptageniid mayflies, in metal-contaminated rivers. Comparative investigation of two caddisflies, Hydropsyche siltalai and Hydropsyche angustipennis, from metal-contaminated rivers in Cornwall and Upper Silesia, Poland respectively, has provided preliminary evidence that this hypothesis is applicable across caddisfly species and contaminated river systems. Use of a combined toxic unit approach, relying on independent data sets, suggested that copper and probably also arsenic are the drivers of mayfly ecotoxicity in the River Hayle and the Red River in Cornwall, while cadmium, lead and zinc are the toxic agents in the Biala Przemsza River in Poland. This approach has great potential as a simple tool to detect the more subtle effects of mixed trace metal contamination in freshwater systems. An informed choice of suitable biomonitor extends the principle to different freshwater habitats over different ranges of severity of trace metal contamination.
authors.affiliation: Kurdistan Institution for Strategic Studies and Scientific Research, Qirga, Sulaimani, 46001, Iraq; University of Human Development, Qirga, Sulaimani, 46001, Iraq; Institute of Environmental Sciences, Jagiellonian University, Krakow, 30-387, Poland. Electronic address: zmnako@kissr.edu.krd.
authors.forename: Zmnako A
authors.initials: ZA
authors.lastname: Awrahman
authors.affiliation: Department of Life Sciences, Natural History Museum, Cromwell Road, London, SW7 5BD, United Kingdom. Electronic address: philipstephenrainbow@gmail.com.
authors.forename: Philip S
authors.initials: PS
authors.lastname: Rainbow
authors.affiliation: Department of Life Sciences, Natural History Museum, Cromwell Road, London, SW7 5BD, United Kingdom. Electronic address: brian.smith@nhm.ac.uk.
authors.forename: Brian D
authors.initials: BD
authors.lastname: Smith
authors.affiliation: Department of Life Sciences, Natural History Museum, Cromwell Road, London, SW7 5BD, United Kingdom; Department of Science and Environment, Roskilde University, Universitetsvej 1, PO Box 260, DK-4000, Roskilde, Denmark. Electronic address: frkhan@ruc.dk.
authors.forename: Farhan R
authors.initials: FR
authors.lastname: Khan
authors.affiliation: Institute of Environmental Sciences, Jagiellonian University, Krakow, 30-387, Poland. Electronic address: wojciech.fialkowski@uj.edu.pl.
authors.forename: Wojciech
authors.initials: W
authors.lastname: Fialkowski
mesh_terms: D000818:Animals; D001682:Biological Availability; D017753:Ecosystem; D004784:Environmental Monitoring; D000075322:Heavy Metal Poisoning; D007313:Insecta / Q000187:drug effects*; D007814:Larva; D011041:Poisoning; D011044:Poland; D045483:Rivers; D014131:Trace Elements / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000493:pharmacokinetics / Q000633:toxicity*
chemical_list: D014131:Trace Elements; D014874:Water Pollutants, Chemical
keywords: Caddisflies; Ecotoxicological effects; Freshwater streams; Mayfly communities; Trace metal bioavailabilities