In 2000, the APVMA released the dichlorvos draft report.
We determined that:
- there were significant occupational health and safety and residue data gaps for some uses of dichlorvos
- the existing data were inadequate to establish or maintain maximum residue limits (MRLs)
- the use of dichlorvos might pose a potential risk to birds, bees, fish and invertebrate aquatic organisms
- there was a potential risk to workers from some dichlorvos application methods
- product labels did not contain adequate instructions or warnings for the safe use of dichlorvos.
The APVMA requested more information from registrants on occupational health and safety and on residue levels to assess any potential risks from the use of dichlorvos.
In the preliminary report we proposed:
- varying product labels to include stronger first aid and safety directions and warnings to minimise the exposure of humans, birds, bees and aquatic organisms
- increasing withholding periods for grain (seven days for grain treated at six parts per million and 28 days for grain treated at 12 parts per million)
- setting temporary MRLs for a number of commodities until further residue data were generated. These include cocoa beans, coffee beans, edible meat and offal (mammalian), eggs, fruits, milks, mushrooms, peanuts, poultry meat and offal, tomatoes and tree nuts and vegetables
- setting an MRL for rice hulls of 50 milligram per kilogram.
The APVMA noted that the Office of Chemical Safety recommended an increase in the acceptable daily intake for dichlorvos from 0.0005 to 0.001 milligrams per kilogram of body weight per day. This is based on a no-observable-effect level for plasma cholinesterase inhibition of 0.013 milligrams per kilogram of body weight per day in human volunteers in a 28-day oral administration study, and using a 10-fold safety factor (to account for variability in human sensitivity).
In 2008 we released the preliminary review findings report for dichlorvos, after receiving additional toxicological information and exposure studies as well as comments after the publication of the draft report. After assessing the new data, the Office of Chemical Safety revised the acute reference dose (ARfD) for dichlorvos. Consequently, both the occupational health and safety assessment in the occupational health and safety component report and the acute dietary risk assessment in the residues component report were revised. The 2008 report included component assessment reports for residues, toxicology, occupational health and safety and the environment.