Toxicity of holmium-labelled clay to four benthic invertebrates / Lee Grapentine ... [et al.]. : En83-9/07-541E-PDF
"Montmorillonite clay adsorbed with the rare earth element holmium (Ha-clay) is a new material produced for tracing movements of fine particles in aquatic systems. However, little is known about the toxicity of Ha-clay, and its potential environmental effects. To investigate effects of Ha-clay on aquatic biota, four benthic invertebrate species (Chironomus riparius, Hexagenia spp., Hyalella azteca, Tubifex tubifex) were exposed to Ha-clay alone and mixtures of 10, 25 and 50% Ha-clay with field-collected reference sediment for 10-28 days in standard laboratory toxicity tests. Overall, only the 100% Ha-clay treatment resulted in significantly higher toxicity than the reference sediment. Mean survival at the end of the exposures to 100% Ha-clay was 7, 53, 2 and 100% for Chironomus, Hexagenia, Hyalella and Tubifex, respectively. Exposure to a negative control treatment of 100% clay resulted in minor reductions in growth, but no lethal responses. Highest concentrations of Ho at which no toxicity was observed were 1400 ug/g for sediment and 11 ug/L for water. Potential impacts of Ha-clay released into natural waters would be expected only where Ha-clay persists in sediment at proportions >50% for at least several days"--Abstract, p. ii.
Permanent link to this Catalogue record:
publications.gc.ca/pub?id=9.849833&sl=0
| Department/Agency | Canada. Environment Canada. Canada. Water Science and Technology Directorate. |
|---|---|
| Title | Toxicity of holmium-labelled clay to four benthic invertebrates / Lee Grapentine ... [et al.]. |
| Series title | WSTD contribution no. 07-541 |
| Publication type | Series - View Master Record |
| Language | [English] |
| Format | Electronic |
| Electronic document | |
| Note(s) | "4 October 2007". Digitized edition from print [produced by Environment and Climate Change Canada]. Includes bibliographic references. Includes abstract in French. |
| Publishing information | [Burlington, Ont.] : [Water Science and Technology Directorate, Environment Canada], 2007. |
| Author / Contributor | Grapentine, Lee C. (Lee Curtis), 1961- |
| Description | iii, 28 p. : ill. (some col.) |
| Catalogue number |
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| Subject terms | Water management Water quality Sediments |