NIOSH French/WHO/International Program on Chemical Safety/Intern. IPCS INCHEM. The Risk Assessment Information System. Sécurité et santé au travail : INRS. SIRI MSDS Index. ITER. ITER is a free Internet database of human health risk values and cancer classifications for over 680 chemicals of environmental concern from multiple organizations worldwide. ITER is the only database that presents risk data in a tabular format for easy comparison, along with a synopsis explaining differences in data and a link to each organization for more information. Search Original ITER Search ITER on TOXNET ITER is currently available at its "Original ITER" location ( and is also available as part of the TOXNET compilation of databases ( The Risk Information Exchange (RiskIE) is a companion database to ITER.
RiskIE is a database of notifications about a variety of human health risk assessment projects that are underway or recently completed. Welcome Page | Page d'accueil. NIOSH redirector /niosh/npg/npgd0000.html. Skip directly to local search Skip directly to A to Z list Skip directly to navigation Skip directly to site content Skip directly to page options CDC Home CDC 24/7: Saving Lives. Protecting People.™ <div class="noscript"> Note: Javascript is disabled or is not supported by your browser. NIOSH HomeNIOSH Pocket Guide to Chemical Hazards NIOSH Pocket Guide to Chemical Hazards NIOSH Homepage Facebook Reccomend Twitter Tweet Share Compartir This Page Is No Longer Available has moved. Contact Us: National Institute for Occupational Safety and Health (NIOSH) Centers for Disease Control and Prevention 800-CDC-INFO (800-232-4636) TTY: (888) 232-6348 New Hours of Operation 8am-8pm ET/Monday-Friday Closed Holidays Contact CDC-INFO File Formats Help: How do I view different file formats (PDF, DOC, PPT, MPEG) on this site?
A-Z Index for All CDC Topics. Institut National de l'Environnement Industriel et des Risques - TOXNET. Furetox, Moteur de recherche. TOXNET. Products & Services: CHEMINFO. Alert & Response Operations. Integrated Risk Information System (IRIS) Chemical Awareness. INCHEM SIDS. ATSDR HAP. ATSDR Home. INERIS - Institut National de l'Environnement Industriel et des. Chemical Reactivity Worksheet (CRW) | Planning for Environmental. The Chemical Reactivity Worksheet (CRW) is a free software program you can use to find out about the chemical reactivity of thousands of common hazardous chemicals.
Download the Chemical Reactivity Worksheet for Windows, Mac, or iPad. Reactivity is the tendency of substances to undergo chemical change, which can result in hazards—such as heat generation or toxic gas byproducts. The CRW predicts possible hazards from mixing chemicals and is designed to be used by emergency responders and planners, as well as the chemical industry, to help prevent dangerous chemical incidents.
The chemical datasheets in the CRW database contain information about the intrinsic hazards of each chemical and about whether a chemical reacts with air, water, or other materials. It also includes case histories on specific chemical incidents, with references. The Compatibility Chart shows the predicted hazards of mixing the chemicals in a mixture in an easy-to-use graphical interface. National Toxicology Program. Chélation. Un article de Wikipédia, l'encyclopédie libre. Complexe chélate de l'EDTA avec un cation métallique Le « chélate » se distingue du simple « complexe » par le fait que le cation métallique est fixé au chélateur par au moins deux liaisons de coordination définissant un cycle avec le métal, à la manière d'une pince, d'où le nom.
Le nombre de liaisons métal-ligand qu'il est possible de former définit la « denticité » : on parle de coordinats bidentes, tridentes, tétradentes, etc, ainsi que de ligands monodentates, bidentates, polydentates. L’atome central est lié aux atomes voisins par au moins deux liaisons en formant une structure annulaire, un cycle chélate. Les cycles chélates les plus stables sont les cycles chélates à 5 et à 6 chaînons. Grâce à cet effet, les chélates sont des complexes plus stables que les complexes de ligands monodentes comportant les mêmes fonctions chimiques.
Typologie des chélateurs[modifier | modifier le code] Fonctions biologiques[modifier | modifier le code]