Life cycle assessment environmental fate

Full life cycle assessment of solvent. Does its manufacture use more noxious materials than it replaces What is the ultimate environmental fate of the solvent ... 

This last outcome was the starting point for the work to be done during the second part of the project. At this point, the different work packages focused on their topics, that is, in environmental fate, toxicology, risk assessment, life cycle assessment, and socioeconomic issues. The objective was to apply the different methodologies related to these fields of knowledge to the selected substances in order to assess the potential risk that they can pose to the human health and the environment. 

Product stewardship means "responsibly managing the health, safety, and environmental aspects of raw materials, intermediate, and consumer products throughout their life cycle and across the value chain in order to prevent or minimize negative impacts and maximize value" [7], Chapter 2 of this book discusses the technical tools that a product steward uses to achieve this goal. These tools include the techniques to characterize and predict the fate and transport of chemicals in the environment upon their manufacture and use. The tools also include the methods used to calculate the possible risks to human health and the environment that may result. Chapter 2 also describes the formal process of life cycle assessment, which uses these tools to evaluate the potential effects on the environment as a result of the production, use, and disposal or recycling of a product. 

Life cycle assessment involves an inventory analysis to provide information about the consumption of material and release of wastes from the point that raw material is obtained to make a product to the time of its ultimate fate, an impact analysis to consider the environmental and other impacts of the product, and an improvement analysis to determine the measures that can be taken to reduce impacts. A life cycle assessment gives a high priority to the choice of materials in a way that minimizes wastes. It considers which materials and whole components can be used or recycled. And it considers alternate pathways for manufacturing processes or, in the case of chemical manufacture, alternate synthesis routes. 

A life-cycle assessment (LCA) chronicles the life of a commercial product from manufacture to disposal ( cradle to grave ) in order to estimate its true cost and, at the same time, to discover how the product s life cycle might be modified to increase profitability within the framework of existing laws and regulations. The familiar admonitions to reduce, reuse, recycle seek to apply LCA concepts to both ends of products life cycles by minimizing both inputs of natural resources and the amounts of waste products. When applied to toxic chemicals, an LCA examines the quantities of toxics used in manufacturing a product, the exposure of workers who make the product and of consumers who use it, and the environmental fate and transport of toxic chemicals after the product is disposed of. Pollution prevention is based on the life-cycle-assessment approach and has been embraced by many governments. 

An understanding of the environmental fate of these elements is necessary in the total assessment of associated health risks. Mercury is known to cycle between the geosphere and biosphere (35). Once in the hydrosphere, it can be converted by sediment flora into highly toxic methylmercury whereupon it is incorporated into aquatic life and ultimately accumulates in human food chains (31). Limited bacterial conversion of inorganic to organic mercury has been shown to occur in soil humus (36) and in animal tissue as well (37). There is no evidence that alkylated mercury is generated from coal combustion directly if it did it would probably be dissociated to the elemental form (14). 

There are a number of ways to approach the assessment of the environmental risk that may be associated with a process. Whatever strategy might be chosen, however, some general risk areas should be part of the overall assessment. First, the inherent hazard, fate, and effects of the materials in the process need to be determined and assessed from an environmental perspective. Second, the potential for any process or unit operations releases need to be identified and evaluated. Third, environmental impacts from transportation, storage, and disposal options associated with the materials used in the process need to be identified and evaluated. Finally, the environmental life cycle impacts of producing those materials need to be collected and assessed. 

The Stockholm Convention on Persistent Organic Pollutants has released dossiers on short chain CPs (SCCPs), which include reviews of environmental levels [7, 8]. In Japan, a detailed study of SCCP flows and releases throughout their product life cycle has been conducted [9]. In addition to assessment reports, there are a number of recent comprehensive review articles, which have included environmental levels, trends, and fate [10, 11] as well as earlier reviews [12-14]. 

Huijbregts, M.A.J., Struijs, J., Goedkoop, M., Heijungs, R., Hendriks, A.J., Van de Meent, D., 2005a. Human population intake fractions and environmental fate factors of toxic pollutants in life cycle impact assessment. Chemosphere 61 (10), 1495—1504. 

Different factors included in the process covered the entire life cycle (cradle-to-grave) of a chemical raw material production, manufacture, product use, and fate (Clark, 2006). The major elements of the environmental assessment include primary energy use, raw materials use, emissions to all media, toxicity, safety risk, and land use (Shonnard et al., 2003). However, the number of LCA studies that evaluate bioprocesses and bio-based chemicals with respect to environmental and economic benefits is limited (Gemgross, 1999 Vink et al., 2003). 

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