MASTThis report was prepared as an account of work sponsored by an agency of the United States Government, Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied. or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product. o r process disclosed. or represents that its use would not infringe privately owned rights. Reference 8-58-5 8-6A-iii c.5Diagram of the biokinetic model for systemic tungsten used in G-7Stages in carcinogenesis as described by Kouri, Henry, G-41Graphical comparisons of potencies completed in LIST OF TABLES 4-10Comparison 5-6Tungsten and uranium content of body organs (g) assuming chronic intake G-31Common scales of toxicological potency for 67 compounds based on RPs to five reference compounds from Table G G-36Fitted values for a log-normal frequency distribution function comparing potency-adjusted 'IDs and maximum doses tested G-43Toxicological test data for sodium chromate (VI) [RTECS #GB2955OOO] . . . . . . . . G-44Summary of the potency of four tungsten compounds and sodium chromate relative to B(a)P, cyclophosphomide, nicotine, aflatoxin B,, and cisplatin all converted to a common scale indexed by unit potency for B(a)P; cyclophosphomide, nicotine, aflatoxin, and cisplatin were standardized according to potencies listed at the bottom of the G-46xii EXECUTIVE SUMMARYThis document summarizes the results from the first phase (Phase I) of a proposed three-year effort to evaluate the environmental acceptability of tungsten (W) as an alternative to depleted uranium (DU) in kinetic energy penetrators (KEPs). The objective of this study was to evaluate the environmental impacts of tungsten in a military context in response to military and congressional concerns regarding exposures to DU. The primary purposes of this Phase I study were to review the literature for existing data; to formulate a test methodology that will provide a useful life cycle assessment of the environmental impacts of tungsten; and to identify where the data gaps exist. In this initial effort, the environmental pathways by which tungsten chemical species (from penetrator impact fragments and aerosols), deposited on the soil, might find their way into humans were identified. In addition, a new computer-based modeling tool was developed which enables predictions of the ways tungsten is retained and distributed in the body. The toxic effects which might be produced were addressed. This approach can be applicable to other materials and, in fact, provides a useful tool for comparing the relative environmental impacts expected from numerous, alternative materials.An extensive review of the literature reveals that little quantitative information and data are available to permit reliable simulations of tungsten toxicity in humans. In particular, the relative corrosion kinetics of each metal, the relative solubilities in corrosive media, and the relative rate of diffus...