Toxic substances in blood: an analysis of current recommendations under a Bayesian (decision) approach

This article extends existing discussion in literature on probabilistic inference and decision making with respect to continuous hypotheses that are prevalent in forensic toxicology. As a main aim, this research investigates the properties of a widely followed approach for quantifying the level of toxic substances in blood samples, and to compare this procedure with a Bayesian probabilistic approach. As an example, attention is confined to the presence of toxic substances, such as THC, in blood from car drivers. In this context, the interpretation of results from laboratory analyses needs to take into account legal requirements for establishing the 'presence' of target substances in blood. In a first part, the performance of the proposed Bayesian model for the estimation of an unknown parameter (here, the amount of a toxic substance) is illustrated and compared with the currently used method. The model is then used in a second part to approach-in a rational way-the decision component of the problem, that is judicial questions of the kind 'Is the quantity of THC measured in the blood over the legal threshold of 1.5 μg/l?'. This is pointed out through a practical example.

Rapid bioassay-guided screening of toxic substances in vegetable oils that shorten the life of SHRSP rats

It has been consistently reported that vegetable oils including canola oil have a life shortening effect in Stroke-Prone Spontaneously Hypertensive Rats (SHRSP) and this toxic effect is not due to the fatty acid composition of the oil. Although it is possible that the phytosterol content or type of phytosterol present in vegetable oils may play some role in the life shortening effect observed in SHRSP rats this is still not completely resolved. Furthermore supercritical CO2 fractionation of canola oil with subsequent testing in SHRSP rats identified safe and toxic fractions however, the compounds responsible for life shortening effect were not characterised. The conventional approach to screen toxic substances in oils using rats takes more than six months and involves large number of animals. In this article we describe how rapid bioassay-guided screening could be used to identify toxic substances derived from vegetable oils and/or processed foods fortified with vegetable oils. The technique incorporates sequential fractionation of oils/processed foods and subsequent treatment of human cell lines that can be used in place of animal studies to determine cytotoxicity of the fractions with structural elucidation of compounds of interest determined via HPLC-MS and GC-MS. The rapid bioassay-guided screening proposed would require two weeks to test multiple fractions from oils, compared with six months if animal experiments were used to screen toxic effects. Fractionation of oil before bio-assay enhances the effectiveness of the detection of active compounds as fractionation increases the relative concentration of minor components.

Region 5 hazardous waste and toxic substances.

Mode of access: Internet.

Regulatory analysis proposed premanufacture notification and review procedures : Toxic Substances Control Act, section 5.

"October 1980."

Development and validation of methods for sampling and analysis of workplace toxic substances /

Mode of access: Internet.

Economic impact assessment of a chlorofluorocarbon production cap : support document, section 6, proposed rule, Toxic Substances Control Act /

"Contract no. 68-01-6236."

Citizens' guide to toxic substances information /

Mode of access: Internet.

Application of the National Environmental Policy Act to U.S. participation in actions of international financial institutions [microform] : hearing before the Subcommittee on Hazardous Wastes and Toxic Substances of the Committee on Environment and Public Works, United States Senate, One Hundredth Congress, second session, June 16, 1988.

CIS Microfiche Accession Numbers: CIS 88 S321-59

Bioaccumulation of toxic substances associated with dredging and dredged material disposal : a literature review /

Mode of access: Internet.

Federal activities in toxic substances /

Mode of access: Internet.

Acquisition and chemical analysis of mother's milk for selected toxic substances /

"December 1980."