Page 192 - Materials Chemistry, Second Edition

178 R.K. Rosenbaum et al.

10.2.3.3 Emission-Related Impacts
For the first type, an emission into the environment, the principal cause–effect chain
may be divided into the following main steps:
• Emission: into air, water or soil (for some product systems also other com-
partments may be relevant such as groundwater, indoor air, etc.)
• Fate: environmental processes causing transport, distribution and transformation
of the emitted substance in the environment. Depending on the physical and
chemical properties of the substance and the local conditions at the site of
emission, a substance may be transferred between different environmental
compartments, be transported over long distances by wind or flowing water, and
be undergoing degradation and transformation into other molecules and
chemical species.
• Exposure: contact of the substance from the environment to a sensitive target
like animals and plants, entire ecosystems (freshwater, marine, terrestrial or
aerial) or humans. Exposure may involve processes like inhalation of air,
ingestion of food and water or dermal contact via skin and other surfaces.
• Effects: observed adverse effects in the sensitive target after exposure to the
substance, e.g. increase in the number of disease cases (ranging from reversible
temporary problems to irreversible permanent problems and death) per unit
intake in a human population or number of species affected (e.g. by disease,
behaviour, immobility, reproduction, death, etc.) after exposure of an ecosystem
• Damage: distinguishing the severity of observed effects by quantifying the
fraction of species potentially disappearing from an ecosystem, or for human
health by giving more weight to death and irreversible permanent problems (e.g.
reduced mobility or dysfunctional organs) than to reversible temporary prob-
lems (e.g. a skin rash or headache)
These steps together constitute the environmental mechanism of the impact
category and their specific features will vary depending on the impact category we
are looking at.

10.2.3.4 Extraction-Related Impacts

For the second type of elementary flow, a resource extraction from the environment,
the principal cause–effect chain may comprise some or all of the following main
steps (with significant simplifications possible for some resources where not all
steps may be relevant, e.g. minerals):
• Extraction or use: of minerals, crude oil, water or soil, etc.
• Fate: (physical) changes to local conditions in the environment, e.g. soil organic
carbon content, soil permeability, groundwater level, soil albedo, release of
stored carbon, etc.