title: Toxic effects of cadmium and zinc on the transmission of Echinoparyphium recurvatum cercariae.
abstract: The toxicity of cadmium, zinc and Cd/Zn mixtures to the transmission of Echinoparyphium recurvatum (Digenea: Echinostomatidae) cercariae into the snail second intermediate hosts was investigated at concentrations ranging from 100 microg l-1 to 10 000 microg l-1 in both soft and hard water. A differential response in the infectivity of metal-exposed cercariae into Lymnaea peregra and Physa fontinalis was demonstrated which was dependent on the snail species being infected. Exposure of L. peregra, P. fontinalis, and L. stagnalis to heavy metals caused a differing susceptibility to E. recurvatum cercariae depending on the snail species being exposed. The mechanism and effects of metal toxicity, together with the importance of the parasite/host strain on cercarial transmission are discussed.
authors.affiliation: School of Biological Sciences, Royal Holloway, University of London, Egham, Surrey, TW20 0EX, UK. n.morley@rhul.ac.uk
authors.forename: N J
authors.initials: NJ
authors.lastname: Morley
authors.forename: M
authors.initials: M
authors.lastname: Crane
authors.forename: J W
authors.initials: JW
authors.lastname: Lewis
mesh_terms: D000818:Animals; D002104:Cadmium / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D004450:Echinostomatidae / Q000187:drug effects* / Q000472:pathogenicity; D008195:Lymnaea / Q000187:drug effects / Q000469:parasitology; D012908:Snails / Q000187:drug effects / Q000469:parasitology*; D013045:Species Specificity; D014201:Trematode Infections / Q000635:transmission*; D014867:Water / Q000737:chemistry; D015032:Zinc / Q000633:toxicity*
chemical_list: D002104:Cadmium; D014867:Water; D015032:Zinc