【正文】 Fisher, 1997。 no information is available on dermal absorption. Qualitatively similar metabolism occurs in mice, rats, dogs, Japanese medaka (Oryzias latipes), and humans (Marshall amp。g/ml for trichloroethanol and trichloroethanol glucuronide and 181。 rather, they include only that information considered critical for characterization of the risk posed by the chemical. The critical studies are, however, presented in sufficient detail to support the conclusions drawn. For additional information, the reader should consult the identified source documents upon which the CICAD has been based. Risks to human health and the environment will vary considerably depending upon the type and extent of exposure. Responsible authorities are strongly encouraged to characterize risk on the basis of locally measured or predicted exposure scenarios. To assist the reader, examples of exposure estimation and risk characterization are provided in CICADs, whenever possible. These examples cannot be considered as representing all possible exposure situations, but are provided as guidance only. The reader is referred to EHC 1701 for advice on the derivation of healthbased tolerable intakes and guidance values. 1 International Programme on Chemical Safety (1994) Assessing human health risks of chemicals: deriviation of guidance values for healthbased exposure limits. Geneva, World Health Organization (Environmental Health Criteria 170). While every effort is made to ensure that CICADs represent the current status of knowledge, new information is being developed constantly. Unless otherwise stated, CICADs are based on a search of the scientific literature to the date shown in the executive summary. In the event that a reader bees aware of new information that would change the conclusions drawn in a CICAD, the reader is requested to contact IPCS to inform it of the new information. Procedures The flow chart shows the procedures followed to produce a CICAD. These procedures are designed to take advantage of the expertise that exists around the world expertise that is required to produce the highquality evaluations of toxicological, exposure, and other data that are necessary for assessing risks to human health and/or the environment. The first draft is based on an existing national, regional, or international review. Authors of the first draft are usually, but not necessarily, from the institution that developed the original review. A standard outline has been developed to encourage consistency in form. The first draft undergoes primary review by IPCS to ensure that it meets the specified criteria for CICADs. The second stage involves international peer review by scientists known for their particular expertise and by scientists selected from an international roster piled by IPCS through remendations from IPCS national Contact Points and from IPCS Participating Institutions. Adequate time is allowed for the selected experts to undertake a thorough review. Authors are required to take reviewers39。 ments into account and revise their draft, if necessary. The resulting second draft is submitted to a Final Review Board together with the reviewers39。g/ml for chloral hydrate and trichloroacetic acid. A parable method for the determination of these chemicals in blood and urine is also available (Breimer et al., 1974). The detection limits are 181。 Owens, 1954。 Henderson et al., 1997。 Abbas amp。 Fox et al., 1990). A child is typically given a higher dose than an adult because a deeper level of sedation is desired to obtain better cooperation from the child during the medical or dental procedure. There is no evidence that a child is less sensitive than an adult to the sedative effects of chloral hydrate. No quantitative information is available from occupational exposure. 7. COMPARATIVE KINETICS AND METABOLISM IN LABORATORY ANIMALS AND HUMANS Chloral hydrate is pletely absorbed following oral administration。 Dalgaard, 1988). The detection limits are 181。N FOREWORD Concise International Chemical Assessment Documents (CICADs) are the latest in a family of publications from the International Programme on Chemical Safety (IPCS) a cooperative programme of the World Health Organization (WHO), the International Labour Organization (ILO), and the United Nations Environment Programme (UNEP). CICADs join the Environmental Health Criteria documents (EHCs) as authoritative documents on the risk assessment of chemicals. CICADs are concise documents that provide summaries of the relevant scientific information concerning the potential effects of chemicals upon human health and/or the environment. They are based on selected national or regional evaluation documents or on existing EHCs. Before acceptance for publication as CICADs by IPCS, these documents undergo extensive peer review by internationally selected experts to ensure their pleteness, accuracy in the way in which the original data are represented, and the validity of the conclusions drawn. The primary objective of CICADs is characterization of hazard and doseresponse from exposure to a chemical. CICADs are not a summary of all available data on a particular chemical。 ments. The CICAD Final Review Board has several important functions: to ensure that each CICAD has been subjected to an ap