Ecological Systems Effects

Part IIA only applies to specific ecological systems, as detailed in Table A of the statutory guidance. These are summarised below:

notified areas of special scientific interest
declared national nature reserves
designated marine nature reserves
notified areas of special protection for birds
Natura 2000 sites, including designated, potential or candidate special areas of conservation and special protection areas
habitats or sites afforded policy protection such as listed Ramsar sites
designated nature reserves
designated or candidate national parks

Harm which is occurring to ecosystems not included in the above descriptions is disregarded for the purposes of Part IIA.

Harm is described in the statutory guidance as:

harm which results in an irreversible adverse change, or some other substantial adverse change, in the functioning of the ecosystem.
harm which affects any species of special interest which endangers the long-term maintenance of the population of that species.
for Natura 2000 sites only, harm which is incompatible with the favourable conservation status of natural habitats or species.

Whilst consideration of ecosystem effects has many similarities to human health effects, it some ways it is more complex as a multitude of organisms and communities of these organisms need to be considered. However, in other aspects ecosystem effects may be easier to quantify as testing can often be done on the component of the ecosystem of concern. As with human health effects:

many organisms have varying sensitivities to chemicals;
different organisms have different exposure scenarios;
some substances may be essential to different components of the ecosystem; and
some species may have acquired a natural tolerance to some contaminants.

All these factors need to be taken into account when considering harm.

There are two approaches that can be taken when considering harm to ecosystems: a chemical approach in which assessment criteria are derived from available toxicity data; and a direct toxicity assessment approach where assessment criteria are derived through actual measurement of harm at the site under consideration. Neither approach is well developed at this moment in time, although the following documents may assist

Environment Agency Consultation:

Ecological Risk Assessment - A framework and methods for assessing harm to ecosystems from contaminants in soil - Consultation on an Ecological Risk Assessment - A framework and methods for assessing harm to ecosystems from contaminants in soil. How stakeholders can respond.

(Consultation closed 31 March 2004)

A guidance manual and protocol for assessing potential adverse effects of substances in soil on designated terrestrial ecosystems: SR(99)01, available from the Foundation for Water Research (FWR), Allen House, The Listons, Liston Road, Marlow, Bucks SL7 1FD Tel: 01628 891589, email, web site .