Document ID: chunk:federal_register_of_legislation:F2013C00288:reg:2:p4
Version: federal_register_of_legislation:F2013C00288
Segment Type: reg
Provision Reference: reg 2 (pt 4/5)
Character Range: 2608861–2612502

is derived based on a LOAEL of 1 mg/kg/day associated with abnormal renal morphology from a 90-day rat bioassay and a 1-year interim report from a 2 year rat study, and an uncertainty factor of 100.

Based on the available data above, there is general agreement from Australian and international sources on the consideration of an oral toxicity reference value of 0.01 mg/kg/day.

No dermal or inhalation specific studies or data are available. For the presence of 2,4-D in soil (not during use), it is considered appropriate to consider the use of the available ADI for all pathways of exposures.

2.4.3         Recommendation
On the basis of the discussion above, the following toxicity reference values (TRVs) have been adopted for 2,4-D in the derivation of HILs:

2.5              Calculated HILs
On the basis of the above, the following HILs have been derived for 2,4-D (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           900                              59                                              --                 41  <1
Residential B           1600                             27                                              --                 73  <1
Recreational C          1300                             43                                              --                 57  <1
Commercial D            9000                             21                                              --                 79  <1

-- Pathway not included in derivation of HIL

2.6              References
APVMA 2006, Preliminary Review Finding (Environment) Part 1: 2,4-D Esters. The Reconsideration of Approvals of the Active Constituents 2,4-D, Registrations of Products Containing 2,4-D and their Associated Labels, Australian Pesticides and Veterinary Medicines Authority, Canberra, Australia.
IARC 1987, Summaries and Evaluations, Chlorophenoxy herbicides, Supplement 7: (1987), p.256, International Agency for Research on Cancer.
Ibrahim ,MA, Bond, GG, Burke, TA, Cole, P, Dost, FN, Enterline, PE, Gough, M, Greenberg, RS, Halperin, WE, McConnell, E, Munro, IC, Swenberg, JA, Zahm, SH & Graham, JD 1991, 'Weight of the Evidence on the Human Carcinogenicity of 2,4-D', Environmental Health Perspectives, vol. 96, pp. 213222.
FAO/WHO (1997), Pesticide residues in food — 1996, Evaluations 1996, Part II — Toxicological, World Health Organization, International Programme on Chemical Safety, Joint FAO/WHO Meeting on Pesticide Residues (WHO/PCS/97.1), Geneva.
FSANZ 2011, The 23rd Australian Total Diet Study, Food Standards Australia and New Zealand.
NEPC 1999, Schedule B (7a), Guideline on Health-Based Investigation Levels, National Environment Protection (Assessment of Site Contamination) Measure, National Environment Protection Council, Australia.
NHMRC 2011, National water quality management strategy, Australian drinking water guidelines, National Health and Medical Research Council, Australia.
OCS 2012, ADI List, Acceptable Daily Intakes for Agricultural and Veterinary Chemicals, current to 31 March 2012, Australian Government, Department of Health and Ageing, Office of Chemical Safety (OCS), available from: http://www.health.gov.au/internet/main/publishing.nsf/content/E8F4D2F95D616584CA2573D700770C2A/$File/ADI-apr12.pdf.
US EPA 2004, Risk Assessment Guidance for Superfund, Volume I: Human Health Evaluation Manual (Part