A new Certified Reference Material for radionuclides in Irish sea sediment (IAEA-385).

A new Certified Reference Material (CRM) for radionuclides in sediment (IAEA-385) is described and the results of the certification process are presented. Eleven radionuclides ((40)K, (137)Cs, (226)Ra, (228)Ra, (230)Th, (232)Th, (234)U, (238)U, (238)Pu, (239+240)Pu and (241)Am) have been certified and information mass activities with 95% confidence intervals are given for seven other radionuclides ((90)Sr, (210)Pb((210)Po), (235)U, (239)Pu, (240)Pu and (241)Pu). Results for less frequently reported radionuclides ((60)Co, (99)Tc, (134)Cs, (155)Eu, (224)Ra and (239)Np) and information on some activity and mass ratios are also reported. The CRM can be used for quality assurance/quality control of the analysis of radionuclides in sediment samples, for the development and validation of analytical methods and for training purposes.

New chelating sorbents based on pyrazolone containing amines immobilized on styrene-divinylbenzene copolymer-I Synthesis and analytical characterization.

A series of new cheating sorbents has been prepared by modification of styrene-divinylbenzene copolymer with different pyrazolone-containing amines. The substances were characterized by elemental analysis and infared spectroscopy. The complexation ability of the sorbents towards alkali, alkaline-earth, transition and precious metals has been studied. The new sorbents may successfully be applied to the simultaneous preconcentration of alkaline-earth and transition elements in neutral medium and to the selective separation of precious metals in acidic medium.

A study on the mutagenic effect of some Bulgarian drugs using the Salmonella/microsome test.

It has been shown that mixtures of phenobarbital and 3- methylcholantrene may be used in the Salmonella/microsome test as inductors of the S9 liver fraction, instead of "Aroclor 1254". The Salmonella/microsome method has been used to study the mutagenic action of Flatogel (2.5% polymethylsyloxanum activatum and 2% ethylium -p- aminobenzoicum , suspended in sorbitol-balanced gel of aluminum hydroxidatum and magnesium hydroxidatum ), Nitrolong (2,2-bis/hydroxymethyl/-1,3- propandioltetranitrate ) and Cymethidine (N-cyano-N'-methyl-N"/2-/5-methyl-4-imidazolyl-methylthio/ethyl/guanidin e). These substances are produced as drugs by the Bulgarian chemical and pharmaceutical industry ( PHARMACHIM ). The results obtained show that the drugs studied have no mutagenic action, both without and with activation with S9 liver fraction isolated from rats treated with "Aroclor 1254" or combinations of phenobarbital and 3- methylcholantrene .