Tuna fishes were collected in the Straits of Messina (Italy), were dissecte
d and dorsal muscles minced, freeze-dried, ground and sieved. The obtained
powder was stabilised by gamma-irradiation and filled into brown glass bott
les. The homogeneity and stability at +20 degrees C and +40 degrees C were
verified with regards to the total arsenic, dimethylarsinic acid and arseno
betaine contents. Ten laboratories participated in the certification study.
All participants had demonstrated beforehand their ability to produce accu
rate results for the As speciation in fish tissue. The certified values are
: total arsenic (4.8 +/- 0.3) mg/kg, arsenobetaine (52 +/- 3) mu mol/kg, di
methylarsinic acid (2.0 +/- 0.3) mu mol/kg. The material is available from
the BCR since early 1998.