Document ID: chunk:federal_register_of_legislation:F2013C00288:reg:5:p4
Version: federal_register_of_legislation:F2013C00288
Segment Type: reg
Provision Reference: reg 5 (pt 4/5)
Character Range: 2644480–2647966

Joint FAO/WHO Meeting on Pesticides Residues (JPMR, 2007) identified a group ADI (for atrazine, diethyl-atrazine, di-isopropyl-atrazine and diaminochlorotriazine) of 00.02 mg/kg/day based on oestrous cycle disruption.
WHO (2011)          ADI = 0.02 mg/kg/day     Group ADI for atrazine and its chloro-s-triazine metabolites (reviewed in 2011) is based on a NOAEL of 1.8 mg/kg/day identified on the basis of luteinizing hormone surge suppression and subsequent disruption of the oestrous cycle seen at
                                             3.6 mg/kg body weight per day in a 6-month study in rats, using a safety factor of 100
RIVM (2001)         TDI = 0.005 mg/kg/day    TDI based on a NOAEL of 0.5 mg/kg/day associated with reproductive effects in rats, and a 100-fold uncertainty factor.
ATSDR               No evaluation available
US EPA (IRIS 2012)  RfD = 0.035 mg/kg/day    The US EPA (available from IRIS) have derived an oral RfD of 0.035 mg/kg/day. The value was last reviewed in 1993 and is based on a NOAEL of 3.5 mg/kg/day associated with decreased body weight gain from a 2-year rat study, and an uncertainty factor of 100.

While the most recent review by WHO (2011) provides a less conservative ADI, the current Australian ADI of 0.005 mg/kg/day is considered relevant and appropriate for consideration in the derivation of a soil HIL.

No dermal or inhalation-specific studies or data are available. For the presence of atrazine in soil (not during use in herbicide products), it is considered appropriate to consider use of the available threshold ADI for all pathways of exposures.

5.4.3         Recommendation
On the basis of the discussion above the following toxicity reference values (TRVs) have been adopted for atrazine in the derivation of HILs:

5.5              Calculated HILs
On the basis of the above, the following HILs have been derived for atrazine (refer to Appendix B for equations used to calculate the HILs and Appendix C for calculations):
HIL Scenario            HIL (mg/kg)                      Percentage Contribution from Exposure Pathways
Ingestion of Soil/Dust  Ingestion of Home-grown Produce  Dermal Absorption of Soil/Dust                  Inhalation (dust)
Residential A           320                              43                                              --                 57  <1
Residential B           470                              16                                              --                 84  <1
Recreational C          400                              27                                              --                 73  <1
Commercial D            2500                             12                                              --                 88  <1

-- Pathway not included in derivation of HIL

5.6              References
APVMA 2008, Atrazine, Final Review Report and Regulatory Decision, Australian Pesticides & Veterinary Medicines Authority, March 2008.
ATSDR 2003, Toxicological Profile for Atrazine, US Department of Health and Human Services, ATSDR, September 2003, available from http://www.atsdr.cdc.gov/ToxProfiles/tp.asp?id=338&tid=59.
IARC 1999, IARC Monographs on the Evaluation of Carcinogenic Risks to Humans, Some Chemicals That Cause Tumors of the Lungs or Urinary Bladder in Rodents and Some Other Substances, World Health Organization, International Agency for Research on Cancer, Lyon, France.
JMPR 2007, Pesticide Residues in Food, 2007, Joint FAO/WHO Meeting on Pesticide