Document ID: chunk:federal_register_of_legislation:F2013C00288:reg:4:p2
Version: federal_register_of_legislation:F2013C00288
Segment Type: reg
Provision Reference: reg 4 (pt 2/4)
Character Range: 2436323–2440012

and inhalation exposures associated with particulates outdoors and indoors are expected to be of less significance than ingestion of soil. While likely to be negligible, potential inhalation exposures associated with dust have been considered in the HIL derived.

    4.3.4         Plant Uptake
No data is available on the potential for the uptake of cresols into edible fruit and vegetable crops. Limited data is also available on the potential or cresols to bioaccumulate. Cresols are soluble in water and, based on Koc values referenced by OECD SIDS (2003), there is a low sorption potential for cresols. Hence, while specific data is lacking, there is the potential for cresols to be available in soil water to be taken up by plants.

Hence a conservative approach has been taken to consider the potential for the uptake of cresols into home-grown produce in the derivation of HIL A. This has been undertaken on the basis of the equations presented in Appendix B, with the following parameters and plant uptake factors estimated:
Parameter                                                                    Value              Reference/Comment
Parameters
Koc                                                                          307 (cm3/g)        RAIS (2010)
log Kow                                                                      1.95               RAIS (2010)
Diffusivity in water                                                         9.78x10-6 (cm2/s)  RAIS (2010)
Calculated Plant Uptake Factors (mg/kg produce fresh weight per mg/kg soil)
Green vegetables                                                             0.18               calculated
Root vegetables                                                              0.255              calculated
Tuber vegetables                                                             0.152              calculated
Tree fruit                                                                   0.00044            calculated

    4.3.5         Intakes from Other Sources – Background
Limited information is available on background exposures to cresols by the general population. Available reviews by ATSDR (2008), OECD SIDS (2003) and RIVM (2001) have not been able to quantify background intakes due to a lack of data. As data is lacking for background intakes of cresols, an estimate or default value can be assumed. Cresols are expected to be widely present in the environment and hence a value of 50% may be relevant where data are not available.

4.4              Identification of Toxicity Reference Values

    4.4.1         Classification
The International Agency for Research on Cancer (IARC) has not classified cresol with respect to human carcinogenicity.
US EPA has classified cresols as Group Cpossible human carcinogen.

    4.4.2         Review of Available Values/Information
There is no adequate data available to assess carcinogenicity of cresols. One study suggests cresols may promote skin tumours. Genotoxicity of cresols has been evaluated (ATSDR 2008) and the weight of evidence suggests that 'cresols do not pose a genotoxic threat to humans under normal environmental exposure conditions'. On the basis of the available information, it is considered appropriate that a threshold dose-response approach be adopted for cresols.

Few quantitative toxicity values are available, however the following are available from Level 1 Australian and International sources:

Source              Value                    Basis/Comments
Australian
ADWG                No evaluation available
OCS (2012)          No evaluation available
International
WHO (1995)          ADI = 0.17 mg/kg/day     ADI derived by WHO