Factors affecting 210Po and 210Pb activity concentrations in mussels and implications for environmental bio-monitoring programmes

Carvalho, F; Oliveira, J; Alberto, G

HERO ID

699936

Reference Type

Journal Article

Year

2011

Language

English

PMID

21145143

HERO ID 699936
In Press No
Year 2011
Title Factors affecting 210Po and 210Pb activity concentrations in mussels and implications for environmental bio-monitoring programmes
Authors Carvalho, F; Oliveira, J; Alberto, G
Journal Journal of Environmental Radioactivity
Volume 102
Issue 2
Page Numbers 128-137
Abstract The activity of (210)Po and (210)Pb was determined in mussels of the same size (3.5-4.0 cm shell length) sampled monthly over a 17-month period at the Atlantic coast of Portugal. Average radionuclide concentration values in mussels were 759±277 Bq kg(-1) for (210)Po (range 460-1470 Bq kg(-1) dry weight), and 45±19 Bq kg(-1) for (210)Pb (range 23-96 Bq kg(-1) dry weight). Environmental parameters and mussel biometric parameters were monitored during the same period. Although there was no seasonal variation of radionuclide concentrations in sea water during the study period, the concentration of radionuclide activity in mussels varied seasonally displaying peaks of high concentrations in winter and low concentrations in summer. Analysis of radionuclide data in relation to the physiological Condition Index of mussels revealed that (210)Po and (210)Pb activities in the mussel (average activity per individual) remained nearly constant during the investigation period, while mussel body weight fluctuated due to fat storage/expenditure in the soft tissues. Similar variation of radionuclide concentrations was observed in mussels transplanted from the sea coast into the Tejo Estuary. However, under estuarine environmental conditions and with higher food availability throughout the year, transplanted mussel Condition Index was higher than in coastal mussels and average radionuclide concentrations were 210±75 Bq kg(-1) (dry weight) for (210)Po and 10±4 Bq kg(-1) (dry weight) for (210)Pb, therefore lower than in coastal mussels with similar shell length. It is concluded that the apparent seasonal fluctuation and inter-site difference of radionuclide concentrations were mostly caused by mussel body weight fluctuation and not by radionuclide body burden fluctuation. This interpretation can be extended to the apparent seasonal fluctuation in concentrations of lipophilic and lipophobic contaminants in mussels, and provides an explanation for occasional high concentrations of (210)Po and man-made contaminants measured in mussels far from pollution sources.
Doi 10.1016/j.jenvrad.2010.11.003
Pmid 21145143
Wosid WOS:000287339100007
Is Certified Translation No
Dupe Override No
Is Public Yes
Language Text English
Keyword Polonium-210; Lead-210; Mussels; Condition index; Environmental monitoring; Mussel watch