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Environment substance, definition

The most widely accepted definition of green chemistry is the design, development and implementation of chemical processes and products to reduce or eliminate substances hazardous to human health and the environment . This definition has been expanded into 12 Principles of Green Chemistry 1... [Pg.1]

EXTREMELY ELAMMABLE (Where the substance or preparation falls within the definition given in Notes 3c) 9. DANGEROUS LOR THE ENVIRONMENT in combination with risk phrases 10 50... [Pg.7]

Several definitions of pollution prevention can be found in the literature (e.g., El-Halwagi and Petrides, 1995 Freeman, 1995 Theodore et al, 1994 Noyes, 1993). These definitions vary in the scope of pollution prevention. Throughout this book, the term pollution prevention will be used to describe any activity that is aimed at reducing, to the extent feasible, the release of undesirable substances to the environment. Other terms such as waste minimization, reduction, and management will be used interchangeably as synonyms for pollution prevention. [Pg.2]

Corrosion is the deterioration of a substance or its properties because of a reaction with its environment. For our purposes, we can be a little more precise in this definition therefore, corrosion is a destructive attack of a metal by either chemical or electrochemical reaction with a given environment [183J. [Pg.1259]

Pollution is defined as the introduction by man into the environment of substances liable to cause hazards to human health, harm living resources and ecological systems, damage structure or amenity, or interfere with legitimate use of the environment. This all-embracing definition includes the impact of polymers on the environment, both in their original form as raw materials. [Pg.161]

The degree of realism of these model structures can be assessed by comparison of computed properties with experimental ones. The cohesive energy is, by definition, the difference in energy per mole of substance between a parent chain in its bulk environment and the same parent chain in vacuo, i.e., when all intermolecular forces are eliminated. This difference is readily computed from the minimized... [Pg.167]

The inventory results should be presented in clear form, how much and what substances from the environment enter the system and how much get out. These results serve for subsequent life cycle impact assessment [48], The aim of the life cycle impact assessment is to measurably compare the environmental impacts of product systems and to compare their severity with new quantifiable variables identified as impact category. The impact categories are areas of specific environmental problems such as global warming, climate changes, acidification, eutrophication, ecotoxicity and others. Already in the phase of definition of the LCA study scope, it is necessary to describe what impact category will be applied and which of their environmental mechanisms will serve as a basis for impact assessment [46],... [Pg.269]

The SFA requires the definition of respective substances, a comprehensive analysis of the system (i.e. boundaries), and it is always limited in its extent due to process properties and data availability. Within this chapter the implementation of SFA for tracing hazardous substances in international informal e-waste treatment has been proved to be a useful method. To assess the hazardous consequences and potential risks of the selected chemicals to humans and the environment caused by informal recycling activities in those regions, different models exist, from which four have been chosen according to their specific focus and various pros and cons. [Pg.469]

A common definition of green chemistry, which clearly encompasses considerable chemical engineering as well, is the design, development and implementation of chemical processes and products to reduce or eliminate substances hazardous to human health and the environment, (P. T. Anastas and J. Warner, Green Chemistry Theory and Practice, Oxford University Press, Oxford, 1998). A more recent article expands this definition to twelve principles (M. Poliakoff, J. M. Fitzpatrick, T.R. Farren and P.T. Anastas, Science, 297, 807-810 (2002). [Pg.153]

For the purposes of this investigation-rather than adopting any single definition of a reactive chemicaT-CSB focuses on the broadest range of practices to identify reactive hazards and to manage the risk of reactive incidents. A reactive chemical may include any pure substance or mixture that has the capability to create a reactive incident. CSB defines a reactive incident as a sudden event involving an uncontrolled chemical reaction-with significant increases in temperature, pressure, or gas evolution-that has caused, or has the potential to cause, serious harm to people, property, or the environment. [Pg.296]

Environment As mentioned previously, a chemical product has to be produced for a particular function. Its existence is determined in the presence of the environment that it interacts with. This is to say, different from a chemical substance, the chemical product needs an environment to be defined. There is no empty space there must be a system and an environment. Therefore, this environment also needs a definition, which is established in the application field, and market for a particular chemical product. [Pg.462]

This chapter has attempted to analyze the nature of a chemical product. It is an entity with different chemical substances, manufactured for one or more applications. Along with other descriptions and definitions, this promotes an understanding of how the product is formed, its organization, and how it interacts with the environment. [Pg.471]

In snmmary, many of the specific chemicals in petroleum are hazardous because of their chemical reactivity, fire hazard, toxicity, and other properties. In fact, a simple definition of a hazardons chemical (or hazardous waste) is that it is a chemical substance (or chemical waste) that has been inadvertently released, discarded, abandoned, neglected, or designated as a waste material and has the potential to be detrimental to the environment. Alternatively, a hazardons chemical may be a chemical that may interact with other (chemical) snbstances to give a prodnct that is hazardous to the environment. Whatever the case, methods of analysis mnst be available to determine the nnrture of the released chemical (waste) and from the data predict the potential hazard to the environment. [Pg.153]

Hamers T, Aldenberg T, van de Meent D. 1996. Definition report indicator effects toxic substances (Itox). No. 607128 001. Bilthoven (The Netherlands) National Institute of Public Health and the Environment (RIVM), 95 p. [Pg.339]


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Environment , definition

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