Document ID: chunk:federal_register_of_legislation:F2013C00288:reg:5:p5
Version: federal_register_of_legislation:F2013C00288
Segment Type: reg
Provision Reference: reg 5 (pt 5/7)
Character Range: 1023706–1026995

is widely available because it is used for the classification of manufactured chemicals for supply. Studies of acute effects using animal experiments may produce information on oral, dermal and inhalation toxicity, skin and eye irritation and skin sensitisation.

Standard protocols are available, such as OECD test guidelines (OECD 1998), resulting in a high degree of standardisation of available information. Acute reference doses are also available for some substances from the Australian Government (for example, pesticides – Table 4) and from the US EPA's IRIS database. Another source of guidelines covering acute effects is the US NOAA public exposure guidelines which can be found at:
http://response.restoration.noaa.gov/topic_subtopic_entry.php?RECORD_KEY%28entry_subtopic_topic%29=entry_id,subtopic_id,topic_id&entry_id(entry_subtopic_topic)=659&subtopic_id(entry_subtopic_topic)=24&topic_id(entry_subtopic_topic)=1.

The soil HILs, and most contaminated land risk assessments, focus on chronic effects. This is because in most circumstances soil contamination capable of causing acute health effects would be self-evidently unacceptable. However, acute effects can be important during remediation works (for example, inhalation of vapours resulting in dizziness) and should not be ignored in hazard identification.

There can also be potential for physical hazards, for example, fire, explosion, and subsurface gas accumulation leading to asphyxiating atmospheres. These are managed by techniques beyond the scope of this Schedule though the hazard identification process should acknowledge them.

    5.2.2          Chronic threshold effects
Chronic threshold effects cover all kinds of chronic toxicity other than cancer as well as those compounds that exhibit 'threshold' toxicity as described for non-genotoxic carcinogens. This may include sub-chronic effects (medium term, for example, less than 10% of a lifetime), effects on reproduction, or development of the foetus.

When assessing hazards, attention should be given to the derivation of threshold reference values and the relevance of that derivation to the environmental contaminants under consideration. Toxicity assessment should seek to identify hazards that are relevant to the form of the contaminant in soil, water or air and should not assume 'worst-case' toxicity on the basis of substances or exposure pathways that are implausible, for example, where the effect was based on an occupational study looking at the inhalation of metal fumes. Since the metal in soil would not be capable of causing fumes, this hazard would be inapplicable and could be reasonably discounted.

Hazard identification for these compounds should detail the following:
    * the IARC classification (classification table presented in this Schedule)
    * the kinds of chronic toxic effect that might result, and what kind of studies these conclusions are based on
    * differences in effects between oral, dermal or inhalation exposure
    * any specific susceptible groups in the population
    * the reliability of the available information.

    5.2.3          Chronic cancer effects
Chemicals may cause cancer in a wide variety of ways, termed modes of action. There is flexibility in defining modes of action, which can be