(JP11174027-A)   NOVELTY - Determination of toxic halogen levels in halogen-containing compounds (HCC) comprises use of thermal electrons formed inside a mass spectrometer operated under electron capture conditions to give negative ions.    USE - For the specification and quantification of various halogenated species, including halogen atom ions and clusters, especially in rubbers.    ADVANTAGE - The method accurately indicates the types and levels of different toxic halogen in rubbers, specifically but not exclusively bromobutyl rubbers to ensure that rubber handlers are not exposed to unsafe levels of such toxins. It enables halogens of concern, i.e. toxic halogens, to be detected when ''buried'' under many more abundant non-halogenated compounds, which would be difficult to detect by any other method. It enables monohalogen compounds to be distinguished from dihalogen compounds, and Cl2, Br2, and ClBr halogens and their mixtures to be distinguished. The method avoids some drawbacks of previous methods, e.g. failure to distinguish between Br and Cl and inability to determine the number of halogen atoms in a molecule.    (US6060325-A)   NOVELTY - Determination of toxic halogen levels in halogen-containing compounds (HCC) comprises use of thermal electrons formed inside a mass spectrometer operated under electron capture conditions to give negative ions.    USE - For the specification and quantification of various halogenated species, including halogen atom ions and clusters, especially in rubbers.    ADVANTAGE - The method accurately indicates the types and levels of different toxic halogen in rubbers, specifically but not exclusively bromobutyl rubbers to ensure that rubber handlers are not exposed to unsafe levels of such toxins. It enables halogens of concern, i.e. toxic halogens, to be detected when ''buried'' under many more abundant non-halogenated compounds, which would be difficult to detect by any other method. It enables monohalogen compounds to be distinguished from dihalogen compounds, and Cl2, Br2, and ClBr halogens and their mixtures to be distinguished. The method avoids some drawbacks of previous methods, e.g. failure to distinguish between Br and Cl and inability to determine the number of halogen atoms in a molecule.