RESIDUE AND ANALYTICAL ASPECTS
Parathion was first evaluated by the JMPR in 1965 and extensively re-evaluated in 1991 and 1995. The 1991 JMPR recommended an MRL of 0.05 mg/kg for apple. The proposed MRL was advanced to Step 7B by the 1994 Session of the CCPR and subsequently held there, pending re-evaluation by the present Meeting.
The analytical method used in trials reported to the Meeting was based on temperature-programmed GLC with FP detection. Parathion and paraoxon were both determined with LODs of 0.01 mg/kg and recoveries above 80%.
Information on registered uses and national MRLs was recorded in the 1991 JMPR evaluation. New information on registered uses on pome fruits was provided only for France.
Information was submitted on residues from six supervised trials on apples in central and southern France in 1994. These were studies of residue decline and showed that parathion residues decreased from 0.13-0.51 mg/kg at 0 day to <0.01-0.08 mg/kg after 21 days. Residues of paraoxon were not detected. Since the trials were with a 50% higher application rate than French GAP, the Meeting could not change the previous recommendation.
The Meeting was informed that another eight trials in France and Spain are planned. The Meeting noted that parathion is scheduled for periodic review in 2000.
