Fluoride Concentration in Antarctic Marine Crustaceans

Full description

Metadata record for data from ASAC Project 587
See the link below for public details on this project.

From the abstracts of some of the referenced papers:

The concentration of fluoride in the body parts of a range of Antarctic crustaceans from a variety of habits was examined with the aim of determining whether fluoride concentration is related to lifestyle or phylogenetic grouping. Euphausiids had the highest overall fluoride concentrations of a range of Antarctic marine crustaceans examined; levels of up to 5477 micro grams per gram were found in the exoskeleton of Euphausia crystallorophias. Copepods had the lowest fluoride levels (0.87 micrograms per gram) whole-body); some amphipods and mysids also exhibited relatively high fluoride levels. There was no apparent relationship between the lifestyle of the crustaceans and their fluoride level; benthic and pelagic species exhibited both high and low fluoride levels. Fluoride was concentrated in the exoskeleton, but not evenly distributed through it; the exoskeleton of the head carapace and abdomen contained the highest concentrations of fluoride, followed by the feeding basket and pleopods, and the eyes. The mouthparts of E. superba contained almost 13,000 microgams F per gram dry weight. Antarctic krill tail muscle had low levels of fluoride. After long-term (1 to 5 year) storage in formalin, fluoride was almost completely lost from whole euphausiids.

A series of experiments was carried out to determine the relationship between feeding, moulting, and fluoride content in Antarctic krill (Euphausia superba). Starvation increased the intermoult period in krill, but had no effect on the fluoride concentrations of the moults produced. Addition of excess fluoride to the sea water had no direct effect on the intermoult period, the moult weight, or moult size. Additions of 6 micrograms per litre and 10 micrograms per litre fluoride raised the fluoride concentrations of the molts produced and of the whole animals. The whole body fluoride content varied cyclically during the moult cycle, reaching a peak 6 days following ecdysis. Fluoride loss at ecydsis could largely be explained by the amount of this ion shed in the moult.

This work was completed as part of ASAC projects 41 and 587 (ASAC_41, ASAC_587).

Lineage

Progress Code: completed

Statement: Euphausia superba have been maintained live in the laboratory of the Australian Antarctic Division (AAD) headquarters since 1981; experimental individuals were drawn from this stock. The AAD also stores bulk krill at a temperature of about -20 degrees C; smaller batches are also preserved in formalin. In order to determine the effect of these storage methods on the concentration and distribution of fluoride within the krill, samples of frozen (-20 degrees C) and formalin-preserved krill were taken for ion-selective electrode (ISE) fluoride-analysis. For comparison, fresh samples were analysed using the same procedure. Several species of Antarctic crustaceans were collected from Prydz Bay during January and February 1993, using trawls from the RSV 'Aurora Australis'. These included mysids, amphipods, gammarids, copepods and euphausiids. The dates provided in temporal coverage are approximate only.