Acephate 35 4. EVALUATION OF DATA FOR ACCEPTABLE DAILY INTAKE AND ACUTE DIETARY INTAKE FOR HUMANS, MAXIMUM RESIDUE LEVELS AND SUPERVISED TRIAL MEDIAN RESIDUE VALUES 4.1 ACEPHATE (095) RESIDUE AND ANALYTICAL ASPECTS Acephate was last evaluated by the JMPR in 2005 and 2003 when an ADI of 0-0.03 mg/kg bw per day, an ARfD of 0.1 mg/kg bw per day were established and a number of maximum residue levels were estimated. The residue for compliance with MRLs was defined as acephate, but for dietary intake estimation it was decided that methamidophos residues should also be taken into consideration. Results of supervised trials carried out on cranberry according the US registered uses were submitted for evaluation. Results of supervised residue trials The compound can be applied either as broadcast treatment at a rate of 1.12 kg ai/ha with a 90 day PHI, or as two chemigation (applied in irrigation) treatments at a rate of 1.68 kg ai/ha with a PHI of 60 days. During the 1976 to 1981 growing seasons 39 field trials were conducted on cranberries in three geographical regions of USA. For each test, single or multiple broadcast foliar applications of acephate were made with individual application rates of 0.563.36 kg ai/ha resulting in total application rates of 1.12 to 13.4 kg ai/ha/season. Cranberry fruit samples were taken between 6 and 131 days following the last application. Exact storage intervals were not reported for each sample in these studies. Samples were stored frozen from harvest to analysis for up to 16 months. Storage stability tests for various intervals were reported by the 2003 JMPR for several crops. The results suggest that the decrease in residues during storage was not significant. The cranberry samples were extracted with ethyl acetate, cleaned up on GPC column and detected with NPD. The stated limits of quantification were 0.02 mg/kg for acephate and 0.01 mg/kg for methamidophos. Average of concurrent recoveries of acephate and methamidophos from mature berries fortified at 0.25 mg/kg and 0.1 mg/kg were 84.8% and 80.6%, respectively. Three trials were performed at approximate US GAP. The average acephate residues in replicate samples were 0.06, 0.18 and 0.2 mg/kg (methamidophos residue was not detectable). The Meeting estimated a maximum residue level of 0.5, HR of 0.2 and STMR of 0.18. The Methamidophos residues in cranberry fruits should be below 0.01 mg/kg. In seventrials, performed with 3 to 5 applications of 0.843.36 kg ai/ha at each timing, cranberry cocktail (cranberry juice) was prepared from the fruits harvested between 1446 days after the last application. The total residues (sum of acephate and methamidophos) in fruit and cocktail (juice) were: 36 Aldicarb Total residues mg/kg Fruit 0.425 0.745 1.15 1.15 1.15 1.95 2.25 Cocktail 0.15 0.26 0.26 0.13 0.62 0.59 0.71 Fp 0.35 0.35 0.23 0.11 0.32 0.26 0.28 Estimated processing factor median: 0.28 average: 0.27 DIETARY RISK ASSESSMENT Long-term intake The GEMS/Food regional diets specify the following long-term cranberry consumption (g/day per person) for various cluster diets: A (0.1); D (0.3); F (0.6); M (2.5). The consumption of cranberry in other regions is nil. The highest IEDI in the 13 GEMS/Food regional diets, based on estimated STMR, was 0.03% of the maximum ADI (0.03 mg/kg bw). The Meeting concluded that the long-term intake of residues of acephate from use on cranberry will not practically increase the intake of residues from other uses considered earlier by the JMPR. Short-term intake The GEMS/Food regional diet specifies the large portion sizes of cranberry of 3.53 g/kg bw for adults and 6.78 g/kg bw for children (both are from the USA). The IESTIs of acephate calculated on the basis of the large portion size and the estimated HR of 0.2 mg/kg are 0.71% and 1.4% of the ARfD for adults and children, respectively. The Meeting concluded that the short-term intake of residues resulting from the use of acephate on cranberry that have been considered by the JMPR is unlikely to present a public health concern. 4.2 ALDICARB (117) RESIDUE AND ANALYTICAL ASPECTS Aldicarb residues were last evaluated by the JMPR in 2001 and 2002. In 2001 residues in individual units of banana and potato and a processing study on potato were evaluated. The Meeting recommended a maximum residue level of 0.2 mg/kg for banana and confirmed a previous recommendation of 0.5 mg/kg for potato. The IESTI calculated for banana, potato and microwaved potato exceed the ARfD for aldicarb (0.003 mg/kg bw) for both the general population (excluding women of child-bearing age) (140160% above the ARfD) and children (330560% above the ARfD). A variability factor of 5 was used in the calculation of the intake for banana. In 2002, based on additional residue data provided from individual banana fingers and composite samples, the Meeting recommended the application of a variability factor of 3 for the calculation of the IESTI of aldicarb in banana. The refined IESTI represented 40% ARfD for the general population and 110% ARfD for children. Aminopyralid 37 For potato, a highest residue from individual unit data of 1.2 mg/kg was used in the first term of the equation for case 2a, with no variability factor (see Chapter 3 of 2003 JMPR Report). The HR from a composite sample (0.45 mg/kg) was used in the second part of the equation. At its 35th, 36th, 37th and 38th Sessions, the CCPR returned the draft MRL for banana and potato to Step 6 due to acute intake concerns. The Committee requested that the JMPR consider using alternative GAPs to estimate lower MRLs (see General Considerations 2.3). The present Meeting received GAP information for potato from the government of The Netherlands. The residue definition of aldicarb is the sum of aldicarb, aldicarb sulfone and aldicarb sulfoxide, expressed as aldicarb. Results of supervised residue trials Banana Based on twenty four trials conducted in France (Guadalupe and Martinique) and Côte d’Ivoire submitted to the 2001 JMPR with bagged and unbagged banana according to GAP, the Meeting recommended a HR of 0.10 mg/kg in banana pulp and a maximum residue level of 0.2 for aldicarb in banana. No additional residues trials or GAP information were provided. The Meeting concluded that none of the residue data relating to available GAP suggests a lower maximum residue level to replace the current proposal of 0.2 mg/kg for aldicarb in banana. Potato Forty five trials conducted in Europe and USA with aldicarb in potatoes according to GAP were evaluated by the 2001 JMPR. Twenty trials were conducted according to GAP of the Netherlands (furrow application at 12.8 g/100m, corresponding to 1.7 kg ai/ha or broadcast application of 3.36 kg ai/ha), giving a highest residue of 0.36 mg/kg. Nine trials conducted according to GAP in Greece, Italy and Spain (furrow at 2.5 kg ai/ha) gave a highest residue of 0.45 mg/kg. In Europe, the PHI is 90 days. Sixteen trials conducted in the USA (GAP of 3.36 kg ai/ha with a PHI of 150 days, positive displacement) gave a highest residue of 0.20 mg/kg. New GAP information in the Netherlands indicates a furrow application of 0.75 kg ai/ha and broadcast application of 3 kg ai/ha with no specified PHI. Ten furrow trials (at 13 g/100m) previously evaluated against the Netherlands GAP do not match the new GAP. The residues derived from the 35 trials, according to the current GAP, in ranked order were: < 0.02, < 0.03 (3), 0.02 (2), 0.03 (6), 0.04 (6), 0.05, 0.06 (4), 0.09, 0.10, 0.11, 0.12, 0.13, 0.14, 0.18, 0.20 (2), 0.27 (2), 0.36 and 0.45 mg/kg. The Meeting concluded that none of the residue data relating to available GAP suggests a lower maximum residue level to replace the current proposal of 0.5 mg/kg for aldicarb in potato. 4.3 AMINOPYRALID (220) TOXICOLOGY Aminopyralid is the ISO approved name for 4-amino-3,6-dichloropyridine-2-carboxylic acid (CAS No. 150114-71-9). It is a postemergence auxin-type herbicide used for the control of a wide variety of broadleaf weed species. Aminopyralid has not been evaluated previously by the JMPR and was scheduled for evaluation at the request of the CCPR. 38 Aminopyralid During the preparation of the toxicological working paper and before the present meeting, it became apparent at a late stage that, in addition to the free acid, the substance on which toxicological data had been submitted, the triisopropanolamonium (TIPA) salt and the potassium salt were also used as active ingredients in some parts of the world. From publicly available information from several toxicological studies, there was evidence that the TIPA salt is appreciably more potent than the free acid. However, these studies had not been submitted to the JMPR. In response to a question from the Meeting, the sponsor explained that this effect was most likely to be due to differences in absorption kinetics as a consequence of the respective physicochemical properties of the compounds, and the different vehicles used to administer the compounds.