Document ID: chunk:federal_register_of_legislation:F2013C00288:reg:5:p10
Version: federal_register_of_legislation:F2013C00288
Segment Type: reg
Provision Reference: reg 5 (pt 10/18)
Character Range: 2996894–3000583

outdoor inhalation of vapours derived from soil
This exposure pathway considers exposure to chemical vapours released from soil into indoor and outdoor air. The indoor inhalation of soil-derived vapours is often the most critical exposure pathway for volatile contaminants. Further detail on this exposure pathway is presented in Section 5.5 of this Schedule.

    5.3.5         Consumption of home-grown produce
This exposure pathway considers the potential transfer of soil contamination to adults and children, through the consumption of garden vegetables and fruit grown in soils within contaminated sites. This exposure pathway has only been considered in the derivation of the HIL values for the low-density residential setting (HIL A values).

An assessment of exposure via the consumption of home-grown produce depends on these factors:
    * the potential for plant uptake to be of significance (compound-specific)
    * the rate of contaminant uptake by home-grown produce from the surrounding soil
    * the rate of consumption of home-grown produce by those in the household
    * the bioavailability of contaminants when ingested in food (where relevant).
This last factor is assumed to be 100% for all contaminants, with the exception of lead.
The equations relevant to the assessment of intakes via the consumption of home-grown produce are included in Appendix B.

5.3.5.1         Fruit and vegetable consumption
Vegetable and fruit intakes per day are assumed to be the suggested average intakes presented in enHealth (2012b). A vegetable intake of 100 g/day and a fruit intake of 180 g/day were estimated for a 23-year-old child. The average vegetable and fruit intakes for 1965-year-old adults were estimated to be 260 g/day and 140 g/day respectively.

For the purpose of deriving the HILs, produce has been divided into four categories; green vegetables (for example, lettuce and spinach), root vegetables (for example, carrots and onions), tuber vegetables (for example, potatoes) and fruit. The percentage of vegetable consumption comprised of green, root and tuber vegetables was calculated using data provided by EA (2009e) and is summarised in Table 7.

These percentages were applied to the consumption rates above, resulting in splitting the vegetable consumption rates into rates for the three vegetable categories. The fruit consumption rate could not be split into different kinds of fruit due to lack of data.

Table 7. Percentage of fruit and vegetable consumption comprising separate produce groups
Produce group                                                                                Adult residents* (%)  Adult residents consumption Rate** (g/day)  Child residents* (%)  Child resident consumption rate** (g/day)
Green vegetables                                                                             59                    153.4                                       55                    55
Root vegetables                                                                              18                    46.8                                        17                    17
Tuber vegetables                                                                             23                    59.8                                        28                    28
Tree fruit                                                                                   100                   140                                         100                   180
* Percentage of total vegetables or fruit, from EA (2009e)
** Calculated based on total vegetable and fruit intakes from Australian data (noted above)

5.3.5.2         Consumption of home-grown