Self-classification

Report on the Advisory List for Self-Classification of Dangerous Substances... 

The Danish EPA has developed an advisory list for self-classification of dangerous substances including 20 624 substances. The substances have been identified by means of QSAR models (Quantitative Structure-Activity Relationship) as having acute oral toxicity, sensitization, mutagenicity, carcinogenicity, and/or danger to the aquatic environment. 

Manufacturers, importers, or downstream users usually classify and label chemicals under their own responsibility. This approach is called self-classification. It means that companies evaluate all available information concerning the intrinsic properties of a particular substance or mixture by applying to it the relevant classification criteria. However, since the available information or interpretation of data may differ from one company to another, each self-classification may result in a different classification and labeling for the same substance. From a regulatory point of view, classification and labeling discrepancies are problematic because they impede a consistent hazard communication on the chemicals market and may put at risk the appropriate protection of humans and the environment. 

Denmark, and the Danish Environmental Protection Agency (DK-EPA), is one of the leading countries in terms of considering the pros and cons to environmental (Q)SARs. It published an advisory list for self-classification of potentially hazardous substances based on predictions from (Q)SAR models (among these the EPI Suite) on hazards to the aquatic environments and human health risks. A total of 46707 existing substances were examined, identifying 20624 substances that, according to... 

Table 19.5 Summary of the Main Models That Were Applied by the Danish EPA for Self-Classification Purposes... 

This document describes the GHS. It contains harmonized classification criteria and hazard communication elements. In addition, guidance is included in the document to assist countries and organizations in the development of tools for implementation of the GHS. The GHS is designed to permit self-classification. The provisions for implementation of the GHS allow the uniform development of national policies, while remaining flexible enough to accommodate any special requirements that might have to be met. Furthermore, the GHS is intended to create user-friendly approach, to facilitate the work of enforcement bodies and to reduce the administrative burden. 

One objective of the GHS is for it to be simple and transparent with a clear distinction between classes and categories in order to allow for self classification as far as possible. For many hazard classes the criteria are semi-quantitative or qualitative and expert judgement is required to interpret the data for classification purposes. Furthermore, for some hazard classes (e.g. eye irritation, explosives or self-reactive substances) a decision tree approach is provided to enhance ease of use. 

Danish Environmental Protection Agency (2001) Report on the Advisory List of Self-Classification of Dangerous Substances, Environmental Project No. 636, Miljopro-jekt, Miljostyrelsen. 

REACH - Self classification (hazard) and risk assessment... 

This annex lays down the procedure for self-classification of substances based on the applicable R-phrases. Points are assigned not only to R-phrases based on ecotox-icological hazards but also to toxicological hazard R-phrases. The WGK is determined by the sum of the points assigned to the R-phrases or the default values if test data are not available. 

This annex lays down the procedure for self-classification of mixtures based either on limit values for content of classified components or the experimental data available for the mixture. 

The self-classifications must be submitted to the authorities for registration and publication purposes. From 2001 substances not registered will be considered to be WGK3. 

The main characteristics of the method, developed in our group for reaction classification arc 1) the representation of a reaction by physicochemical values calculated for the bonds being broken and made during the reaction, and 2 use of the unsupervised learning method of a self-organi2ing neural network for the perception of similarity of chemical reactions [3, 4],... 

Til most cases, only one of the two regioisomers is preferentially formed. Wc will show here how reaction classification by a self-organizing neural network can be used for the prediction of the preferred regioisomer in a pyrazole synthesis. 

More elaborate scheme.s can he envisaged. Thus, a. self-organizing neural network as obtained by the classification of a set of chemical reactions as outlined in Section 3,5 can be interfaced with the EROS system to select the reaction that acmaliy occurs from among various reaction alternatives. In this way, knowledge extracted from rcaetion databases can be interfaced with a reaction prediction system,... 

To a large exteat, the vapor pressure of the substance stored determines the shape and, consequently, the type of tank used. The roof shape of a tank may be used to classify the type of tank. This classification is self-explanatory to tank fabricators and erectors. Also important is the tank bottom. 

One useful classification of graphite depends on the mode of formation that leads to three physically distinct common varieties dake, lump, and amorphous. The term dake is self-explanatory dake forms occur disseminated in rock. Lump graphite occurs in fissure-filled veins in pegmatite dikes, also associated with chip and the rarer needle forms. Amorphous graphite occurs in beds that were once coal, but fine-grained, easily ground vein graphite is also classified as amorphous. 

Contracts with the federal government require compliance with Executive Order Nos. 11625 and 12138 to utilize small and small disadvantaged businesses. The contractor/subcontractor must complete a copy of the representations and certifications providing self-certification of business classification under existing federal definitions. The representations and certifications also provide tax identification information required by the Internal Revenue Service. The original of the representation and certification form should be sent to regional purchasing and a copy included in the project file. 

Wood RW, Grubman J, Weiss B Nitrous oxide self-administration by the squirrel monkey. J Pharmacol Exp Ther 202 491 99, 1977 Wood RW, Coleman JB, Schuler R, et al Anticonvulsant and antipunishment effects of toluene. J Pharmacol Exp Ther 230 407 12, 1984 World Health Organization The lCD-10 Classification of Mental and Behavioural Disorders Clinical Descriptions and Diagnostic Guidelines. Geneva, World Health Organization, 1992... 

Collect leaking liquid In sealable containers. Sweep spilled substance into containers if appropriate, moisten first to prevent dusting. Carefully collect remainder, then remove to safe place (extra personal protection self-contained breathing apparatus). UN Classification UN Hazard Class 6.1 ... 

Woolfson and Mahmoud have classified the routes to preparation of decorated self-assembling peptide materials [53] as (1) co-assembly, where the functional part is already attached to a self-assembling component prior to assembly, and (2) postassembly, where a non-functionahsed self-assembled structure is modified by covalent or non-covalent means. This discussion adheres to this classification. A third route, beyond the scope of this review, is the use of structured peptides as templates for inorganic materials. Section 4.1 discusses functionalised self-assemblies formed from co-assembly-type approaches, while post-assembly modifications of self-assembled structures are considered in Sect. 4.2. 

M. Mulholland, D.B. Hibbert, P.R. Haddad and P. Parslov, A comparison of classification in artificial intelligence, induction versus a self-organising neural networks. Chemom. Intell. Lab. Systems, 30 (1995) 117-128. 

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