Protocol for the Derivation of Environmental and Human ... - CCME

Section 2
Level of Ecological Protection and Relevant Endpoints for
Deriving Soil Quality Guidelines
2.1 Level of Ecological Protection
Before soil quality guidelines can be derived, an understanding of the level of ecological protection must
be established if protection goals for the environment are to be effective and sustainable. The level of
protection provided by the guidelines depends on the protection goals sought for individual land use
categories. Therefore, for agricultural and residential/parkland land use, it is necessary to achieve a level
of ecological functioning that sustains the primary activities associated with these land uses. To make
this possible, soil quality guidelines for these land uses are derived using laboratory and field
toxicological data that make predictions on the adverse effects (effects that undermine a species' ability
to survive and reproduce under normal living conditions) of chemicals on key ecological receptors. The
protection goals and endpoints for agricultural and residential/parkland land use are described in
Sections 5.1 and 5.2.
On commercial and industrial lands, the primary land use activities are not directly dependent on the
need to sustain a high level of ecological processes (see Figure 3). The same key ecological receptors
and endpoints examined for agricultural and residential/parkland land uses are also examined for
commercial and industrial land use. However, the SEQCCS has decided that the level of protection for
commercial and industrial land use does not need to be as stringent as for agricultural or
residential/parkland land uses. Accordingly, the degree to which commercial and industrial receptors
may experience adverse effects is increased to correspond with the lower protection levels required for
the land use category. For more information on the key receptors and level of protection sought for
commercial and industrial land use see Section 5.3 and 5.4.
Despite the different levels of protection sought for individual land uses, an important common principle
exists for all land use categories. For each land use, the level of ecological protection provided by the
soil quality guidelines ensures that the remediated land has the potential to support most activities likely
to be associated with that land use (see Figure 3).
2.2 Relevant Effects Endpoints
The term "endpoint" is often used in chemical effects assessment to define the single response factor that
characterizes the impact of the test chemical on a selected organism(s) (SECOFASE, 1993). In
developing generic environmental soil quality guidelines, only the endpoints related to the "direct effects"
of chemical stressors to receptors can be examined, and these do not account for the "indirect effects"
(e.g., avoidance of polluted food items) that may occur from sublethal exposures. Consequently, soil
quality guidelines derived using endpoints from data on direct effects, may mask other less observable
responses that have a cumulative negative effect on organism survival. While this is an area for further
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