[1] Univ Concepcion, Fac Ciencias Vet, Dept Ciencia Anim, Chillan, Chile
[2] Univ Fed Rio de Janeiro, Dept Quim Analit, Rio De Janeiro, Brazil
[3] Univ Fed Rio de Janeiro, Inst Biofis, Radioisotopos Lab, Rio De Janeiro, Brazil
[4] Comis Chilena Energia Nucl, Santiago, Chile