Record Details
Uptake and retention of technetuim [i.e. technetium] by two freshwater species, the crayfish Pacifastacus leniusculus and the snail Juga silicula
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Uptake and retention of technetuim [i.e. technetium] by two freshwater species, the crayfish Pacifastacus leniusculus and the snail Juga silicula |
| Names |
McKenzie-Carter, Michael A.
(creator) Willis, David L. (advisor) |
| Date Issued | 1985-05-01 (iso8601) |
| Note | Graduation date: 1985 |
| Abstract | The patterns of uptake, retention, and tissue distribution of ⁹⁵mTc in two freshwater species, the crayfish Pacifastacus leniusculus and the snail Juga silicula have been investigated. The animals were chronically exposed in water to which sodium pertechnetate had been added. Final whole-body concentration ratios (CR) obtained were 1.6 and 41 for the crayfish and the snail, respectively. Following the uptake study the animals were placed in fresh non-radioactive water for a retention study. Two-phase retention patterns were observed in both species. The long-lived component of the crayfish curve contained 82% of the body burden, while that of the snail contained 90%. Biological half-lives for the long-lived retention components were determined to be 141 days and 120 days for the crayfish and the snail, respectively. Tissue distribution data showed that 79-100% of the crayfish whole-body activity was shared between the exoskeleton and the digestive gland at all times, whereas the soft tissues of the snail contained 82-96% of the whole-body activity. Data from these two species are similar to past research results that indicated uptake of Tc is highly variable among different species. The final crayfish CR value obtained is several orders of magnitude below those reported for the taxonomically-related lobster, and is among the lowest values reported for freshwater invertebrates. Uptake by J. silicula indicates a more significant accumulation of Tc, however a high degree of variation between identical animals was observed. This study suggests that Tc contamination in the two study species would not pose a significant health problem to humans. The crayfish represents a potential direct pathway to man, however the degree to which P. leniusculus concentrated Tc indicates that this would not be a health hazard. The higher degree of concentration by the snail represents a potential indirect hazard. Further studies investigating such factors as variability in individual uptake and the efficiency of trophic transfer of Tc need to be undertaken in order to accurately assess the impact of Tc releases. |
| Genre | Thesis/Dissertation |
| Topic | Technetium |
| Identifier | http://hdl.handle.net/1957/40679 |
