210 Po and 210 Pb in fish and shellfish from Guanabara Bay, Brazil

Abstract

Muscles of forty-four fish of two different species, Mugil spp and Micropogonia fumieri, and six composite samples of the shellfish Perna perna, collected in Guanabara Bay, a tropical estuary, were analysed for 3l0 2l0 Po and Pb contents. The method for °Po determination consisted of spontaneous deposition on copper disks, :i0 followed by alfa counting. The method for Pb determination was mineralization followed by leaching, ion- 2l0 exchange separation, precipitation and, finally, beta counting. The average values found for concentration of Po 1 in fish was 2.6 Bq.kg" , wet basis, while for shellfish the values were higher, reaching 43.8 Bq.kg"', wet basis. For 2l0 Pb, concentrations were very low, frequently below the detection limit for fish samples. For shellfish this was 1 higher, reaching 1.8 Bq.kg" , wet basis.