|Appears in Collections:||Biological and Environmental Sciences Journal Articles|
|Peer Review Status:||Refereed|
|Title:||Seasonal variations in activity concentrations of Tc-99 and Cs-137 in the edible meat fraction of crabs and lobsters from the central Irish Sea|
Hartnoll, Richard G
Johnson, Michael S
uptake and seasonal variation
|Citation:||Copplestone D, Jackson D, Hartnoll RG, Johnson MS, McDonald P & Wood N (2004) Seasonal variations in activity concentrations of Tc-99 and Cs-137 in the edible meat fraction of crabs and lobsters from the central Irish Sea, Journal of Environmental Radioactivity, 73 (1), pp. 29-48.|
|Abstract:||Discharges of most radionuclides into the Irish Sea from the BNFL site at Sellafield have decreased over the past 20 years or so. For a few radionuclides, however, discharges have peaked more recently. Notably, operation of the Enhanced Actinide Removal Plant (EARP) since 1994 has led to an increase in discharges of 99Tc, as a result of the treatment of previously stored waste, with consequent increases in 99Tc activity concentrations in a number of marine species, particularly in crustaceans such as lobsters. Previous research has considered the significance of factors such as sex and body weight on radionuclide concentrations. The current project set out to investigate whether seasonal variations in radionuclide concentrations in crabs and lobsters occur, with particular emphasis on the dynamics of 99Tc and 137Cs. Organisms were obtained from a site off the Isle of Man, where radionuclide concentrations were measurable but the site was sufficiently distant from Sellafield that the radionuclides were well mixed in the water column and not likely to be influenced by the pulsed nature of discharges of 99Tc. Crab and lobster samples were collected monthly, between February 2000 and February 2001. Fifteen or 16 individuals (evenly split as male and female) of each species were collected on each occasion. Seawater samples were also collected over the 12-month period. Activity concentrations of 99Tc in the edible meat fraction (both brown and white meat) ranged from 0.23 to 2.46 Bq kg−1 (fresh weight (fw)) in crabs and 124 to 216 Bq kg−1 (fw) in lobsters, with no observed seasonal variations. Activity concentrations of 137Cs in both crab and lobster were lower, ranging from less than 0.16 to 0.85 Bq kg−1 for crab meat (fw) and less than 0.3 to 3.3 Bq kg−1 for lobster meat (fw). A statistically significant increase in activity concentrations of 137Cs in the meat was observed in the summer months for both crab and lobster. The cause has not been investigated but may be related to the laying down of energy reserves during the active feeding period over the summer. At all times, uptake of 99Tc is higher in the brown meat fraction of both crabs and lobsters, whilst 137Cs is more uniformly distributed. These results are used to discuss the implications for sampling and monitoring pr|
|Rights:||The publisher does not allow this work to be made publicly available in this Repository. Please use the Request a Copy feature at the foot of the Repository record to request a copy directly from the author. You can only request a copy if you wish to use this work for your own research or private study.|
|copplestone_crabsandlobstersirishsea_2004.pdf||281.23 kB||Adobe PDF||Under Embargo until 31/12/2999 Request a copy|
Note: If any of the files in this item are currently embargoed, you can request a copy directly from the author by clicking the padlock icon above. However, this facility is dependent on the depositor still being contactable at their original email address.
This item is protected by original copyright
Items in the Repository are protected by copyright, with all rights reserved, unless otherwise indicated.
If you believe that any material held in STORRE infringes copyright, please contact firstname.lastname@example.org providing details and we will remove the Work from public display in STORRE and investigate your claim.