Comprehensive environmental assessment of a chemical product
 

Two starting points for making a comprehensive assessment of a chemical product can be distinguished;

1. An ERA has been made and the results show a possible risk to the environment. The results from an ERA may however need to be complemented with information from an LCA in order not to choose an alternative product that has other large environmental impacts.
2. A comparative LCA has been made, but one or more alternative products may cause toxic or eco-toxic effects. A comparative LCA may need to be complemented with information from an ERA in order for the products to be compared on equal grounds.

1. Environmental Risk Assessment with a complementary LCA

Risk Management Measures are needed if the result of an ERA indicates a possible risk to the environment from a chemical substance. The Risk Management process that follows includes a Risk benefit analysis that should analyze the impacts and benefits of the substance. In this analysis the substance may be compared with its functional alternatives from a life cycle perspective, i.e. not only focusing on the environmental effects caused by the chemicals themselves, but also including other activities needed for the chemicals to exist. Including an LCA in such a Risk benefit and comparative analysis will give a more holistic picture of the environmental effects caused by using an alternative substance. When looking only at the environmental risk one chemical may seem less deleterious, but the production of this chemical may for example need much more energy. The energy use gives rise to large amounts of carbon dioxide, which in turn affect global warming. 

It may however be difficult to obtain LCA data for the alternative substances, especially if these are produced by other companies and a screening LCA may therefore have to be sufficient. Such a screening LCA may include e.g. only the extraction of needed raw materials and the energy use for the general production processes of the chemicals. The result can then be presented as a comparison of e.g. the use of natural resources and the global warming potential.

1. Try to find the amounts of raw materials and energy used in the life cycles of the chemical products to be compared; extraction of raw materials, formulation, production and use. Focus on the differences between the chemicals in these activities.

2. Life Cycle Assessment with complementary ERA
An LCA does not usually include an assessment of the ecotoxicological effects of all of the emissions in the Life cycle inventory (LCI), since there are at present no generally accepted models for assessing the ecotoxicity of substances in an LCA. Performing an ERA of each of the emitted substances during the life cycle of the substance is not practically achievable since an LCI may include more than a hundred emitted substances.
An ERA of the assessed substance does however give additional information, especially if the substance is known to be toxic.
A comparative LCA of e.g. cloth bleaching products, where the traditional chlorine is compared to less toxic alternatives, would not give a complete picture if the toxicity of the compared products was not included.
A good approach may therefore be to include a screening ERA if the products themselves or other substances in their life cycles are toxic, persistent or bioaccumulating. This information will then complement the LCA as one more parameter to consider in the decision making.

The ERA as well as the LCA methodology are quite complex and time consuming. An initial screening ERA or LCA may therefore be benficial to perform is order to see whether a deeper analysis is necessary. ECETOC (European Centre for Ecotoxicology and Toxicology of Chemicals) has published a web tool for performing screening risk assessments and there are a number of different methods for conducting screening LCAs, of which some can be found in the report State of the art study of LCA and LCC tools.

The ISO 14040 series presents the principles and framework for performing an LCA study and the Technical Guidance for new and existing chemicals (TGD) presents the methodology for performing a Risk Assessment.

More information about the ERA and LCA methodology is presented here.

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