tebufenozide RESIDUES RESULTING FROM SUPERVISED TRIALS

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1 384 RESIDUES RESULTING FROM SUPERVISED TRIALS Trials were carried out in Australia, Canada, Europe, Japan, New Zealand, the USA, and other countries. All trials in Germany and the USA were conducted according to Good Laboratory Practice (GLP). Some trials were designed to determine efficacious use rates and the effects of the timing of applications as well to assess the residues in the crop at various pre-harvest intervals. The field parts of these trials were not conducted according to GLP. The results were not corrected for analytical recoveries unless noted. Analytical recoveries were mostly high (>80%), so using uncorrected or corrected results should not significantly influence the interpretations. Pome Fruits Apples. Eight trials were conducted from November 1992 to March 1993 in Australia (Rouch, 1994) as a randomized block of four duplicates. Four different application rates were used and eight applications were made at 2-week intervals. The spray concentration used were times the proposed GAP rate. The residue values in Table 21 are the averages of samples from duplicate plots. Six small-plot field trials (one tree per plot) were conducted from November 1994 to March 1995 in apples following season-long applications of 70WP and 200 SC in Australia (Armstrong, 1995b) as a randomized block of three replicates. Treatments commenced just at petal fall and continued every two weeks until commercial harvest. A motorized hand sprayer was used. The spray concentrations were kg ai/hl and kg ai/hl. All above-ground parts of each tree were sprayed to near the point of run-off each time. Fruit samples were collected at various PHIs. These trials were at higher rates than the proposed GAP (4-8 applications at 0.18 kg ai/ha, kg ai/hl, 28 days PHI). The average residue was 1.3 mg/kg on day 28. A number of trials were conducted in Canada. In 1993 (Bruns, 1994) three to five applications were made either to three trees per plot or to single tree plots replicated three times in a randomized complete block design. The trees were sprayed to the point of runoff using a handgun. In six trials according to GAP in 1995 (Bruns, 1995) four applications were made at 0.24 kg ai/ha each and the spray intervals ranged from 2 weeks to 3 months. Samples were analysed by a modified HPLC method (Bruns, 1994). The limit of determination was 0.02 mg/kg and the average recovery 77%. In other apple trials in Canada in 1994 (Tillman, 1995a) plots consisted of either four trees or single tree plots replicated three times in a randomized block. The trees were sprayed to runoff with a handgun. Samples were analysed by HPLC according to GLP. Residues of in the trials according to Canadian GAP ranged from 0.06 to 1.1 mg/kg. A series of efficacy trials was carried out in Chile to assess the bioactivity of in controlling the major pome fruit pest, codling moth (Gonzalez, 1995). In one trial samples were analysed for to establish the dissipation rate. In a series of field trials with several different apple varieties in geographically representative apple orchards in France (Tillman, 1994) five to seven applications were usually made at intervals of about 2

2 385 weeks. The analyses were according to GLP but the field parts of the trials were not. In the four trials according to GAP the average residue was 0.1 mg/kg (PHI days). In GLP trials in Germany in 1992 in Germany according to proposed GAP (Raquet et al., 1993) three applications at kg ai/ha (0.013 kg ai/hl) were made with a motorized knapsack sprayer. The apples were analysed by a validated method (Schuld and Holzworth, 1994a). In three other GLP trials in Germany in 1993 (Brusche and Holzwarth, 1995) was applied three times at the maximum proposed rate using a knapsack mist blower to 7-14 trees per plot. The residues in whole fruit in the German trials according to proposed GAP ranged from 0.02 to 0.35 mg/kg. A single trial in 1993 in Greece (AgrEvo, 1995) was not according to actual or proposed GAP. Eight applications were made to a single tree at 2-week intervals. The residues in treated samples were mg/kg and in control samples <0.02 mg/kg. Three of six trials (Tillman, 1994) in Italy in 1992 complied with GAP. Three applications were made at intervals of about 30 days to 6 trees per plot. Apple samples were analysed by GLC with an NPD. Residues in the trials according to GAP ranged from 0.28 to 0.55 mg/kg. Two trials were conducted in Japan according to GAP: 2 applications, 10 days apart, at kg ai/ha (Komatsu and Yabusaki, 1994). The dates of the applications were varied in order to harvest the mature samples with different PHIs. Samples were analysed for the parent compound, RH-1788 and RH RH-6595 was reduced to RH-1788 and both it and were methylated and analysed by GLC (Schuld and Holzwarth, 1994a). The residues of were 0.02 and 0.05 mg/kg. Residues of RH-1788 and RH-6595 were all below the LOD of 0.01 mg/kg. Six residue trials during the 1992/1993 growing season with Gala apples (Tillman, 1995c) and ten during the 1994/95 growing season (Tillman, 1995b) in New Zealand were designed to assess the residues on apples from different use rates at different frequencies and timings. Applications were made by applying 70W to run-off with a hand-held lance. The application rates changed after the first three applications owing to the higher spray volumes. Typical volumes are 2500 to 3000 l/ha, increasing as the foliage becomes denser toward harvest. The trials were with single trees with five replicates. All apple samples were analysed by HPLC (Deakyne et al., 1994b). The LOD of the method was 0.03 mg/kg and recoveries ranged from 68 to 85% in 1992/1993 and from 77 to 120% in 1994/1995. Two trials were conducted in Spain according to proposed GAP (Tillman, 1994). Two trees in each plot were sprayed three times with an atomizer spray. The samples were analysed in France by the method of Mellet (1993a). The residues were 0.37 and 0.54 mg/kg. A series of field trials on apples in a number of States of the USA from 1991 to 1993 (Burnett et al., 1994) were under GLP but not according to proposed GAP. Most trials were with 9 applications of kg ai/ha and a few with 10 applications of kg ai/ha. The plot sizes ranged from 0.54 to 6.19 ha with a minimum of 4 and a maximum of 37 trees in a plot. Samples were analysed by HPLC. The number of applications was greater than that recommended in the proposed GAP.

3 386 Four trials according to the proposed GAP (6 applications at kg ai/ha) in 1994 at two locations in the USA (Dong, 1995d) were designed to compare the 2SC and 70WP formulations. The plot sizes ranged from 2.56 to 2.79 ha. Samples were analysed by HPLC. Residues from proposed GAP ranged from 0.36 to 0.6 mg/kg. The residues from the two formulations were similar. The results of the trials are shown in Table 22. Table 22. Residues of in apples. The underlined residues are from treatments according to GAP. Country, location, year Form. Application PHI, days No. kg ai/ha kg ai/hl Residue, mg/kg Australia SC Rouch, Australia SC Rouch, Australia SC Rouch, Australia SC Rouch, Reference, comments Australia WP Armstrong, 1995b Australia WP Armstrong, 1995b Australia SC Armstrong, 1995b Australia SC Armstrong, 1995b

4 Country, location, year Form. Application PHI, days No. kg ai/ha kg ai/hl 387 Residue, mg/kg Reference, comments Australia WP Armstrong, 1995b Australia WP Armstrong, 1995b Canada SC Bruns, Canada SC Bruns, Canada SC Bruns, <0.05 Canada 1993 SC Bruns, 1994 Canada 1993 SC <0.05 Bruns, 1994 Canada 1993 SC Bruns, 1994 Canada 1994 SC Tillman, 1995a Canada 1994 SC Tillman, 1995a Canada 1994 SC Tillman, 1995a Canada 1994 SC Tillman, 1995a Canada 1994 SC Tillman, 1995a Canada 1994 SC <0.02 Tillman, 1995a Canada 1994 SC <0.02 Tillman, 1995a Canada 1994 SC <0.028 Tillman, 1995a Canada 1994 SC Tillman, 1995a Canada 1994 SC Tillman, 1995a Canada 1994 SC Tillman, 1995a Canada 1994 SC Tillman, 1995a Canada 1995 SC Bruns, 1995 Canada 1995 SC Bruns 1995 Canada 1995 SC Bruns, 1995 Canada 1995 SC Bruns, 1995 Canada 1995 SC Bruns, 1995 Canada 1995 SC Bruns, 1995 Chile SC Gonzalez, 1995

5 388 Country, location, year Form. Application PHI, days No. kg ai/ha kg ai/hl Residue, mg/kg Reference, comments LOD 0.02 mg/kg France SC Tillman, 1994 Agde, 1990 SC control 0.04 mg/kg France SC Tillman, 1994 Grisolles, 1991 SC control 0.15 France SC Tillman, 1994 Bouldon, 1991 SC control 0.07 France SC Tillman, 1994 Barbentane, 1991 SC control <0.05 France SC Tillman, 1994 Meynes, 1991 SC control <0.05 SC SC SC France SC Tillman, 1994 Mauguio, 1991 SC <0.05 control <0.05 France SC Tillman, 1994 Mauguio, 1991 SC control <0.05 France SC Tillman, 1994 Garonne, 1992 SC control <0.05 France SC Tillman, 1994 Pompignac, 1992 SC control <0.01 France SC Tillman, 1994 St. Pardon, 1992 SC control <0.01 SC SC SC SC France SC Tillman, 1994 Barbentane, 1992 SC control <0.01 France SC Tillman, 1994 Boulbon, 1992 SC control <0.01 Germany SC Raquet, 1993 Drage-Elbstorf, (Belgian GAP) Germany SC Raquet, 1993

6 Country, location, year Form. Application PHI, days No. kg ai/ha kg ai/hl 389 Bornheim, Residue, mg/kg Reference, comments 28 <0.02 (Belgian GAP) Germany SC Raquet, 1993 Bodenegg, (Belgian GAP) Germany SC Raquet, 1993 Hoechst, Germany SC Raquet, 1993 Niederdorfelden, 1992 SC Germany SC Brusche, 1995 Drage-Elbe, Germany SC Brusche, 1995 Drage-Elbe, Germany SC Brusche, 1995 Kippenhausen, Greece SC AgrEvo, LOD 0.02 mg/kg Italy SC Tillman, 1994 Baricella BO, Italy SC Tillman, 1994 Baricella BO, Italy SC Tillman, 1994 Gallo FE, 1992 SC Italy SC Tillman, 1994 Baricella BO, 1992 SC Japan FL Komatsu, 1994 Nagano, <0.01 Japan FL Komatsu, 1994 Iwate, <0.01 New Zealand WP 9 3x0.18-6x Tillman, 1995c Hastings, 1992/

7 390 Country, location, year Form. Application PHI, days No. kg ai/ha kg ai/hl Residue, mg/kg Reference, comments New Zealand WP 9 3x0.09-6x Tillman, 1995c Hastings, 1992/ New Zealand WP 6 3x0.18-3x Tillman, 1995c Hastings, 1992/ New Zealand WP 6 3x0.09-3x Tillman, 1995c Hastings, 1992/93 WP New Zealand WP Tillman, 1995c Hastings, 1992/ New Zealand WP Tillman, 1995c Hastings, 1992/ New Zealand WP Tillman, 1995b Hawke's Bay, 1994/ New Zealand WP Tillman, 1995b Hawke's Bay, 1994/ New Zealand WP Tillman, 1995b Hawke's Bay, 1994/

8 Country, location, year Form. Application PHI, days No. kg ai/ha kg ai/hl Residue, mg/kg Reference, comments New Zealand WP Tillman, 1995b Hawke's Bay, 1994/ New Zealand Hawke's Bay, 1994/95 New Zealand Hawke's Bay, 1994/ WP <0.03 Tillman, 1995b WP <0.03 Tillman, 1995b New Zealand WP Tillman, 1995b Nelson, 1994/ New Zealand WP Tillman, 1995b Nelson, 1994/ New Zealand WP Tillman, 1995b Hawke's Bay, 1994/ New Zealand WP Tillman, 1995b Hawke's Bay, 1994/ Spain Epila (Z), 1992 SC Tillman, 1994 Spain Epila (Z), 1992 SC Tillman, 1994 USA SC Burnett, 1994 NY, USA SC Burnett, 1994 PA, USA WA, 1991 SC Burnett, 1994 USA WA, 1992 SC Burnett, 1994

9 392 Country, location, year Form. Application PHI, days No. kg ai/ha kg ai/hl Residue, mg/kg Reference, comments USA NC, 1992 SC Burnett, 1994 USA CA, 1992 SC Burnett, USA OH, 1992 SC Burnett, 1994 USA OR, 1992 SC Burnett, USA VA, 1992 SC Burnett, USA MI, 1992 SC Burnett, 1994 USA WV, 1992 SC Burnett, 1994 USA SC Burnett, 1994 WA, USA SC Burnett, 1994 MI, USA SC Dong, 1995d WA, USA WP Dong, 1995d WA, USA SC Dong, 1995d PA, USA WP Dong, 1995d PA, USA PA, 1991 SC Deakyne, 1994c for processing USA PA, 1994 WP Deakyne, 1995a average of 2 analyses for processing 1 Mean of two plots Pears. In a trial on pears in Australia (Amstrong, 1995) a single tree per plot was used with three replicates. Treatments were with a motorized hand sprayer and each tree was sprayed near to the point of run-off. The application rates were higher than proposed GAP. Samples were analysed by GC-MS. Two trials were carried out in Italy in 1992 with 6 trees per plot. Three applications were made at intervals of 30 days. One trial complied with GAP and showed a residue of 0.23 mg/kg. Several trials in New Zealand were designed to assess the decline of residues at different

10 393 application rates. Single trees were treated, with four replicates. Samples were analysed by HPLC and the reported LOD was 0.03 mg/kg. The residues from treatments closest to GAP ranged from 0.09 to 0.29 mg/kg (Tillman, 1995b). The results are shown in Table 23. Table 23. Residues of in pears. Underlined residues are from trials according to GAP. Country, location, year Form. No. Application PHI, days kg ai/ha kg ai/hl Residue, mg/kg Reference Australia WP Armstrong, 1995c Australia WP Armstrong, 1995c Australia SC Armstrong, 1995c Australia SC Armstrong, 1995c Australia WP Armstrong, 1995c Australia WP Armstrong, 1995c Italy SC Mellet, SC New Zealand WP Tillman, 1995b Hawke's Bay, 1994/ New Zealand WP Tillman, 1995b Hawkes Bay, 1994/

11 394 Country, location, year Form. No. Application PHI, days kg ai/ha kg ai/hl Residue, mg/kg Reference New Zealand WP Tillman, 1995b Hawke's Bay, 1994/ New Zealand WP Tillman, 1995b Nelson, 1994/ <0.03 New Zealand WP Tillman, 1995b Nelson, 1994/ New Zealand WP Tillman, 1995b Nelson, 1994/ New Zealand WP Tillman, 1995b Nelson, 1994/ New Zealand WP Tillman, 1995b Nelson, 1994/ New Zealand WP Tillman, 1995b Nelson, 1994/ Grapes. Several grape trials were carried out in Australia during the years 1992 to 1995, but in all of them the application rates or the number of applications or both were higher than those specified in proposed GAP. The trials in were with high volume sprays to the point of run-off. The reported residues are the averages of samples from duplicate trials at the same rates (Anderson, 1993). The trials were also with high-volume sprays applied to the foliage (Armstrong, 1995). In a large number of trials with red and white grapes at different locations in France between 1990 and 1992 (Gocha, 1995a) the plot sizes ranged from 11 m 2 to 48 m 2 with 5 to 22 vines in each plot. Most trials were with 4 replicates while some others were single or in duplicate. One or two applications were

12 395 made. Samples were harvested at intervals of 0 to 89 days after the (last) application. Only a few of these trials were according to GAP. The original GLC method used in 1990 measured residues with an LOD of 0.04 mg/kg. The extraction and methylation steps were slightly modified for the 1991 analyses to reach an LOD of mg/kg. In 1992, using different chromatographic and methylation conditions, the laboratory was able to reach an LOD of 0.01 mg/kg in both solid and liquid substrates. This method was validated (Mellet, 1993a). Grape samples from two trials were processed to wine or spirit. Three trials in France in 1992 for processing studies (DeWilde et al., 1995a) were conducted with treated and untreated plots without replicates. The plot sizes were chosen according to the quantity of sample to be harvested but were not less than 1 ha. Two trials in 1993 in France for processing studies (DeWilde et al., 1995b) complied with GAP. The plot sizes were not less than 1.4 ha. Applications were made with a motorized knapsack sprayer. Samples were harvested when the grapes reached the maturity required for commercial wine production. The residues in the trials which accorded with French GAP ranged from 0.05 to 0.28 mg/kg. Five trials in Germany were according to proposed GAP (Ulrich et al., 1994). The plot sizes were not less than 0.58 ha. The applications were carried out with a motorized knapsack sprayer. At the last sampling about 200 kg of grapes were taken from at least 30 vines from two trials for processing to must and wine. Samples were analysed by GLC. Four similar trials, again according to proposed GAP, were carried out by Kaiser (1994). mg/kg. Residues in the grapes from the German trials at the proposed 28-day PHI ranged from 0.21 to 0.5 Four trials at two different locations in Italy (Kaiser and Holzwarth, 1994) were at excessive rates and the grapes were vinified. The limit of determination was 0.02 mg/kg for grapes, and 0.01 mg/kg for must, new wine and potable wine. Two trials in Thailand (Ishii and Higuchi, 1995) were not according to GAP or GLP. The results of the supervised trials on grapes are shown in Table 24. Table 24. Residues of in grapes. Underlined residues are from treatments according to GAP. Country, year Form. Application PHI, days No. kg ai/ha kg ai/hl Residue, mg/kg Ref., comments Australia SC Anderson, Australia SC Anderson,

13 396 Country, year Form. Application PHI, days No. kg ai/ha kg ai/hl Residue, mg/kg Ref., comments Australia WP Armstrong, 1995a Australia WP Armstrong, 1995a Australia SC Armstrong, 1995a Australia SC Armstrong, 1995a Australia WP Armstrong, 1995a Australia WP Armstrong, 1995a Australia SC Armstrong, 1995a Australia SC Armstrong, 1995a France SC Gocha, 1995a 1990 SC LOD 0.04 mg/kg France SC Gocha, 1995a 1990 SC <0.04

14 Country, year Form. Application PHI, days No. kg ai/ha kg ai/hl 397 Residue, mg/kg Ref., comments France SC Gocha, 1995a 1990 SC France SC Gocha, 1995a 1990 SC France SC Gocha, 1995a 1990 SC SC France SC Gocha, 1995a 1990 SC SC France SC <0.04 Gocha, 1995a 1990 SC <0.04 SC <0.04 France SC Gocha, 1995a 1990 SC France SC Gocha, 1995a 1990 SC France 1990 SC <0.04 Gocha, 1995a France 1990 SC <0.04 Gocha, 1995a France 1990 SC Gocha, 1995a France 1990 SC Gocha, 1995a France SC Gocha, 1995a France SC Gocha, 1995a France SC Gocha, 1995a 1990 SC LOD mg/kg France SC SC SC

15 398 Country, year Form. Application PHI, days No. kg ai/ha kg ai/hl Residue, mg/kg Ref., comments France SC Gocha, 1995a 1991 SC SC SC SC France SC Gocha, 1995a 1991 SC SC France SC <0.025 Gocha, 1995a 1991 SC SC SC France SC Gocha, 1995a 1991 SC SC France SC Gocha, 1995a 1991 SC France SC Gocha, 1995a 1992 SC LOD 0.01 mg/kg SC France SC Gocha, 1995a 1992 SC SC France SC Gocha, 1995a 1992 SC SC France SC Gocha, 1995a 1992 SC SC France 1992 SC Gocha, 1995a 1992 France SC Gocha, 1995a France 1992 SC Gocha, 1995a France SC Gocha, 1995a

16 Country, year Form. Application PHI, days No. kg ai/ha kg ai/hl Residue, mg/kg Ref., comments France 1992 SC Gocha, 1995a France 1992 SC Gocha, 1995a France 1992 SC Gocha, 1995a 1992 France SC Gocha, 1995a 1992 France SC Gocha, 1995a 1992 France SC De Wilde, 1995a 1992 average of 2 analyses France SC DeWilde, 1995a 1992 average of 2 analyses France SC DeWilde, 1995a 1992 average of 2 analyses France SC DeWilde, 1995b 1993 average of 2 analyses France 1993 SC DeWilde, 1995b Germany SC Ulrich, LOD 0.02 mg/kg Germany SC Ulrich, LOD 0.02 mg/kg Germany SC Ulrich, LOD 0.02 mg/kg Germany SC Ulrich, LOD 0.02 mg/kg Germany SC Ulrich,

17 400 Country, year Form. Application PHI, days No. kg ai/ha kg ai/hl Residue, mg/kg Ref., comments Germany SC Kaiser, 1994a LOD 0.02 mg/kg Germany SC Kaiser, 1994a LOD 0.02 mg/kg Germany SC Kaiser, 1994a LOD 0.02 mg/kg Germany SC Kaiser, 1994a LOD 0.02 mg/kg Italy SC Kaiser, 1994b Italy SC Kaiser, 1994b Italy SC Kaiser, 1994b Italy SC Kaiser, 1994b Thailand SC Ishii, 1995a LOD ± 0.01 mg/kg Thailand SC Ishii, 1995a LOD 0.01 mg/kg Mean of duplicate trials Kiwifruit. A large number of residue trials in New Zealand between 1990 and 1995 (Tillman, 1995d) were

18 401 all with single-vine plots with 5 replicates per treatment in a randomized block design. All applications were made with a motorized hand lance plot sprayer to the point of run-off. Each vine received approximately 6 litres of spray per application, which was reported as being equivalent to 2000 l/ha. The rate of 0.12 kg ai/ha per application was calculated from the reported spray concentration of kg ai/hl and the total spray volume. The trials were conducted to determine the efficacious use rates, to study the effects of the timing of the applications and to assess the residues in the crop at various pre-harvest intervals. The whole fruit samples were analysed by HPLC with HPLC-MS for confirmation (Deakyne et al., 1995). All results were corrected for the analytical recovery, which ranged from 88.8 to 96.6%. The trials were with three alternative use patterns: (a) 4 applications at pre-bloom, 75-95% petal fall, first cover (21-day interval) and second cover (21-day interval); (b) 7 applications, four as (a) followed by three further applications at 21-day intervals; (c) 2 applications at pre-bloom and 75-95% petal fall. Whole kiwifruit were analysed as before. In two trials in the USA in 1995 (Deakyne, 1996) four applications of the 70WP formulation were made at 0.15 or 0.30 kg ai/ha, giving total treatments of 0.60 or 1.20 kg ai/ha. The airblast applications were made at intervals of 6 to 14 days. The plot sizes were ha. Single samples were taken 90 days after the last applications. Whole fruit samples were analysed by the method of Deakyne et al. (1995). The residues in the treated samples were all less than 0.5 mg/kg, even from the higher rate. The results are shown in Table 25. Table 25. Residues of in kiwifruit. Country, location, year Form. Application PHI, days No. kg ai/ha kg ai/hl Residue, mg/kg Reference New Zealand SC 4 a Tillman, 1995d New Zealand SC 4 a Tillman, 1995d New Zealand SC Tillman, 1995d New Zealand SC Tillman, 1995d

19 402 Country, location, year Form. Application PHI, days No. kg ai/ha kg ai/hl Residue, mg/kg Reference New Zealand SC Tillman, 1995d New Zealand WP 3 b Tillman, 1995d New Zealand WP 3 b Tillman, 1995d New Zealand WP 3 b Tillman, 1995d New Zealand WDG Tillman, 1995d New Zealand WDG Tillman, 1995d New Zealand WP 4 c Tillman, 1995d New Zealand WP 4 c Tillman, 1995d

20 Country, location, year 403 Form. Application PHI, days No. kg ai/ha kg ai/hl Residue, mg/kg Reference New Zealand WP 4 c Tillman, 1995d New Zealand WP 7 c Tillman, 1995d New Zealand 1995 WP 7 c Tillman, 1995d New Zealand 1994 WP 2 c Tillman, 1995d New Zealand WP 4 c Tillman, 1995d 1994/ New Zealand WP 4 c Tillman, 1995d New Zealand WP 4 c Tillman, 1995d New Zealand WP 7 c Tillman, 1995d New Zealand WP 7 c Tillman, 1995d 1995 New Zealand 1994 WP 2 c Tillman, 1995d USA WP Deakyne, 1996 CA, 1995 WP USA WP Deakyne, 1996 CA, 1995 WP a Each vine received approximately 5-7 l of spray at each application, which was sprayed to the point of run-off b Each vine received approximately 5 l of spray at each application c Each vine received approximately 6 l of spray at each application

21 404 Vegetable Crops Numerous field trials were conducted at various locations throughout the USA from 1991 to 1993 (Chen et al., 1994c,d; Dong, 1995b,c). Ground applications were either by foliar spray or directly to the soil at intervals of 5 to 10 days. Single samples at each PHI were analysed. The proposed use pattern for leafy vegetables and cole crops in the USA is 7 applications at kg ai/ha with a 7-day PHI. Celery. In trials by Chen et al. (1994d) plot sizes were ha. In two trials samples of both stalk and stalk with foliage were analysed for comparison, while in the others only stalk samples were analysed. Analyses were by HPLC with an LOD of 0.05 mg/kg. The interval from sampling to analysis (SAI) ranged from 150 to 525 days. Dong (1995c) compared the 2SC and 70WP formulations in the USA in with 7 to 9 applications at a rate of kg ai/ha. The plot sizes were 0.74 to 1.24 ha. The SAI was days. The residues of from trials approximating proposed GAP ranged from 0.1 to 0.6 mg/kg in the stalk and were 0.4 and 1.3 mg/kg in stalk with foliage. Two samples of stalk were analysed for RH Both contained <0.01 mg/kg. Table 26. Residues of in celery, USA, State, year Form. Application PHI, days Residue, mg/kg No. kg ai/ha kg ai/hl MI SC Chen, 1994d FL SC Chen, 1994d CA SC * Chen, 1994d * MI SC Chen, 1994d CA SC * Chen, 1994d * MI SC Chen, 1994d CA SC Dong, 1995c CA WP Dong, 1995c Reference

22 405 State, year Form. Application PHI, days Residue, mg/kg Reference No. kg ai/ha kg ai/hl FL SC Dong, 1995c FL WP Dong, 1995c * stalk with foliage Lettuce. Six field trials with head lettuce and four with leaf lettuce were carried out at different locations in the USA (Chen et al., 1994d). The plot sizes ranged from 0.52 to 1.68 ha. In three of the head lettuce trials samples with and without wrapper leaves were analysed and in the other three only samples with wrapper leaves. The LOD was 0.01 mg/kg and the SAI ranged from 246 days to just over three years. In three samples analysed for RH-0897 the residues were all below the LOD of 0.01 mg/kg. Two trials on head lettuce with wrapper leaves and two on leaf lettuce were conducted with formulated as the 2SC and 70WP at 0.14 kg ai/ha (Dong, 1995c). The SAI ranged from 178 to 344 days. Residues from 7-8 applications at 0.14 kg ai/ha, at a 7-day PHI, in head lettuce ranged from <0.01 mg/kg without wrapper leaves to 6.6 mg/kg wrapper leaves, and in leaf lettuce from 1.1 to 3.2 mg/kg. Table 27. Residues of in head lettuce, USA, State Year Form. Application PHI, days No. kg ai/ha kg ai/hl Residue, mg/kg NJ SC Chen, 1994d CA SC <0.01 Chen, 1994d 1991 CA SC Chen, 1994d FL SC Chen, Reference

23 406 State Year Form. Application PHI, days No. kg ai/ha kg ai/hl Residue, mg/kg TX SC Chen, 1994d CA SC Chen, 1994d CA SC Dong, 1995c CA WP Dong, 1995c AZ SC Dong, 1995c AZ WP Dong, 1995c Reference 1 Head without wrapper leaves Table 28. Residues of in leaf lettuce, USA, State, year Form. Application PHI, days No. kg ai/ha kg ai/hl Residue, mg/kg NJ SC Chen, 1994d CA SC Chen, 1994d FL SC Chen, 1994d TX SC Chen, 1994d CA SC Dong, 1995c CA WP Dong, 1995c AZ SC Dong, 1995c AZ WP Dong, 1995c Reference Spinach. Five field trials on spinach were conducted at different locations in the USA. Plot sizes ranged from 0.31 to 2.4 ha (Chen et al., 1994d). Samples from three trials were analysed for RH-0897: all residues were below the LOD (0.01 mg/kg). Other trials were carried out in the USA to compare the 2SC and 70WP formulations. Plot sizes

24 407 ranged from 0.37 to 1.24 ha (Dong, 1995c). The residues of from treatments approximating proposed GAP ranged from 1 to 4.2 mg/kg. Table 29. Residues of in spinach, USA, State, year Form. Application PHI, days Residue, mg/kg Reference No. kg ai/ha kg ai/hl VA SC Chen, 1994d AZ SC Chen, 1994d CA SC Chen, 1994d OK SC Chen, 1994d TX SC Chen, 1994d CA SC Dong, 1995c CA WP Dong, 1995c TX SC Dong, 1995c TX) WP Dong, 1995c Broccoli, cabbage and mustard greens. Seven field trials on broccoli, ten on cabbage, and seven on mustard greens were conducted at various locations throughout the USA from 1991 to 1993 (Chen et al., 1994c). The plot sizes were 0.28 to 2.5 ha for broccoli, 0.60 to 1.23 ha for cabbage, and 0.14 to 2.51 ha for mustard greens. Samples of cabbage with and without wrapper leaves were analysed in some of the trials. The residues in the samples without wrapper leaves were generally significantly lower. Selected samples analysed for RH-0897 showed no residues above the limit of determination (0.01 mg/kg). Dong, (1995b) compared the 2SC and 70WP formulations with 7 to 9 applications at a rate of kg ai/ha. The plot sizes were 0.09 to 1.24 ha for broccoli, 0.60 to 3.01 ha for cabbage, and 1.24 to 1.48 ha for mustard greens. Samples were analysed by the method of Chen et al. (1994a). The results of the trials are shown in Tables 30, 31 and 32.

25 408 The residues from tyreatments approximating proposed GAP in the USA were mg/kg in broccoli, < mg/kg in cabbage with and without wrapper leaves, and mg/kg in mustard greens. Table 30. Residues of in broccoli, USA, State, year Form. Application No. kg ai/ha kg ai/hl PHI, days Residue, mg/kg OR SC Chen, 1994c TX SC Chen, 1994c CA SC Chen, 1994c OR SC Chen, 1994c 1992 VA SC Chen, 1994c 1992 TX SC Chen, 1994c 1992 CA SC Chen, 1994c CA SC Dong, 1995b CA WP Dong, 1995b CA SC Dong, 1995b CA WP Dong, 1995b Reference Table 31. Residues of in cabbage, USA, State, year Form. Application PHI, days No. kg ai/ha kg ai/hl Residue, mg/kg CA SC Chen, 1994c NY SC Chen, 1994c TX SC Chen, 1994c Reference

26 State, year Form. Application PHI, days No. kg ai/ha kg ai/hl Residue, mg/kg GA SC Chen, 1994c OH SC < Chen, 1994c < < FL SC < Chen, 1994c CA SC Chen, 1994c TX SC Chen, 1994c < < WI SC < Chen, 1994c VA SC Chen, 1994c 1993 TX SC Dong, 1995b TX WP Dong, 1995b FL SC Dong, 1995b FL WP Dong, 1995b Reference 1 cabbage head without wrapper leaves Table 32. Residues of in mustard greens, USA,

27 410 State, year Form. Application PHI, days Residue, mg/kg Reference No. kg ai/ha kg ai/hl CA SC Chen, 1994c TX SC Chen, 1994c 1991 CA SC Chen, 1994c CA SC Chen, 1994c NJ SC Chen, 1994c 1992 NJ SC Chen, 1994c AZ SC Chen, 1994c CA SC Dong, 1995b CA WP Dong, 1995b TX SC Dong, 1995b TX WP Dong, 1995b Chilli peppers. A single field trial was carried out in Thailand on Chilli peppers with the 20SC formulation at three different rates on a 0.68 ha plot (Ishii and Higuchi, 1994). Three were 5 applications at intervals of 10 days. The trial was not according to GAP or GLP. The results are shown in Table 33. Table 33. Residues of in Chilli peppers, Thailand, 1993 (Ishii and Higuchi, 1994). Form. Application PHI, days Residue, mg/kg 1 No. kg ai/ha kg ai/hl SC SC SC

28 411 Form. Application PHI, days Residue, mg/kg 1 No. kg ai/ha kg ai/hl SC The reported values are average from duplicate analyses Chinese kale. In a similar trial on Chinese kale with the 20SC formulation at three rates in Thailand in 1993 (Ishii and Higuchi, 1993) the plot size was 0.94 ha. There were 5 sprays 4 days apart. The trial did not comply with GLP or GAP (Table 34). Table 34. Residues of in Chinese kale, Thailand, 1993 (Ishii and Higuchi, 1994). Form. Application PHI, days Residue mg/kg No. kg ai/ha kg ai/hl SC SC SC Rice. A total of eight trials, four of them official, with two different formulations, 0.75DL (dustless) and 10WP, were conducted in Japan (Komatsu and Yabusaki, 1992c). The results of duplicate anaylses were averaged. Rice samples were harvested at maturity: pre-harvest intervals were varied by changing the date of the last spray application rather than the date of harvest. After harvesting, samples were dried and rough rice was dehulled and sieved through a 1.7 mm sieve. Samples of grain and staw were analysed for the parent compound and in some cases for RH-1788 and RH-6595 by the methods of Komatsu and Yabusaki

29 412 (1992a,b). The reported LOD was mg/kg. Two trials were conducted in 1992 in Spain (Mellet, 1993b) with one aerial application at a rate of kg ai/ha. The plot sizes were 5 and 10 ha. Rice was harvested 37 or 54 days after the treatment. Approximately 1 kg each of straw, brown rice and cleaned rice were chosen randomly from the test and control plots. Grain was cleaned in a small pilot plant and the whole straw sample was treated by cutting and mixing. Sub-samples of more than 300 g of grain were then crushed to provide the analytical samples. Only the parent compound was determined. The average recovery was 76.4% from straw and 72.8% from rice. The residues in the straw were much higher than in the rice. The results from Spain and Japan are summarized in Table 35.

30 413 Table 35. Residues of in rice grain and straw. Underlined residues are from treatments according to GAP. Country, Location, year Form. Application Residue, mg/kg Reference / PHI, comments days No. kg ai/ha kg ai/hl Total RH-1788/RH-6595 rice straw rice straw Japan, Chiba DL < Komatsu, 1992c* < < < Japan, Akita DL < Komatsu, 1992c* < < < Japan, Hyogo WP < Komatsu, 1992c* < < Japan, Ohita WP Komatsu, 1992c* Japan, Tokushima WP Komatsu, 1992c Japan, Tochigi WP Komatsu, 1992c Japan, Hiroshima DL Komatsu, 1992c Japan, Hyogo DL <0.005 Komatsu, 1992c < < <0.005 Spain 1992 SC Mellet, 1993b Spain 1992 SC (Brown rice also 0.02) 1.23 Mellet, 1993b DL: Dustless * Official trial Nut crops Pecans. Eight field trials on pecans were conducted in geographically representative States in the USA (Cui and Desai, 1995). Four of them were at the proposed GAP rate, but six applications were made in all the trials whereas five are proposed. The plot sizes ranged from 2.32 ha to ha with 4 to 12 trees per plot. Pecan kernels were analysed for by the method described by Cui and Desai (1994). As shown

31 414 in Table 36, the residues of were below the LOD of 0.01 mg/kg in all the trials, and below the limit of detection of mg/kg in most of them. Table 36. Residues of in pecan kernels, USA, 1993 (Cui and Desai, 1995). State Form. Application PHI, days Residue, mg/kg No. kg ai/ha kg ai/hl TX SC ND 14 ND 28 ND TX SC < ND 28 ND NM SC ND 14 ND 28 ND NM SC ND 14 ND 28 <0.01 AL SC ND 14 ND 28 ND AL SC < ND 28 ND GA SC ND 14 ND 28 ND GA SC ND 14 ND 28 ND ND < limit of detection (0.003 mg/kg) Walnuts. In six field trials on walnuts according to GAP at five sites in the USA in 1992 (Cui et al. 1993c) four applications were made to plots of ha with four trees per plot at monthly intervals. Nut-meat samples were analysed for by the analytical method of Cui et al. (1993a) with an LOD of 0.01 mg/kg. Two field trials in 1994 in the USA were each with both 2SC and 70WP formulations (Dong, 1995a). Four ground applications were made by airblast at the GAP rate of 0.28 kg ai/ha. The plot sizes ranged from 4.46 to 6.83 ha with 6 trees per plot. The LOD was 0.01 mg/kg and the limit of detection mg/kg. Two field trials were conducted in France in 1993 and 1994 (Benzekri, 1995), the 1993 trial with five applications from June to August at various intervals and the 1994 trial with four applications at 3-

32 415 week intervals. The residues of in walnut kernels from applications according to GAP ranged from undetectable (0.003 mg/kg) to 0.02 mg/kg. Table 37. Residues of in walnut kernels. Underlined residues are from treatments according to GAP. Country (state), year Form. Application PHI, days No. kg ai/ha kg ai/hl Residue, mg/kg Reference/Comments USA (CA) SC <0.01 Cui, 1993b ND Limit of detection mg/kg USA (CA) SC Cui, 1993b ND USA (CA) SC <0.01 Cui, 1993b USA (CA) SC Cui, 1993b ND USA (OR) SC ND Cui, 1993b ND USA (OR) SC ND Cui, 1993b ND USA (OR) SC Cui, 1993b ND USA (OR) SC Cui, 1993b <0.01 USA (CA) SC ND Cui, 1993b <0.01 USA (CA) SC Cui, 1993b <0.01 USA (CA) SC Cui, 1993b USA (CA) SC Cui, 1993b <0.01 USA (CA) 1994 SC ND Dong, 1995a. USA (CA) 1994 WP <0.01 Dong, 1995a. USA (CA) 1994 SC ND Dong, 1995a. USA (CA) 1994 WP ND Dong, 1995a. France SC ND Benzekri, Limit of detection mg/kg France 1994 SC ND Benzekri, 1995 ND < Limit of detection; mg/kg Tea. Summaries of two field trials, one of them according to GAP, conducted in Sri Lanka in 1994 were reported (Ishii, 1995b). Critical data such as plot size and type of application were not provided. The analyses were carried out in Japan. The residue in the trial which complied with GAP was 14.6 mg/kg.

33 416 Two trials were conducted according to GAP at different locations in Japan in 1993 (Komatsu and Yabusaki, 1993). Samples were analysed for the parent compound, RH-6595 and RH-1788 by GLC. Residues of the parent compound at the GAP PHI were 11.5 and 11.6 mg/kg. The corresponding levels of RH were 0.23 and 0.24 mg/kg. The residues found in dry and brewed tea from the trials in Sri Lanka and Japan are shown in Table 38. Table 38. Residues of in dry and brewed tea from SC applications. Underlined residues are from treatments according to GAP. Country Year Application No. kg ai/ha PHI, days Dry tea Residue, mg/kg Brewed tea Reference Sri Lanka Ishii, 1995b Sri Lanka Ishii, 1995b Japan Komatsu, Animal feeding study In a study in Japan two cows were dosed by capsule with either 40 or 400 mg bw day for 7 days (Inoue, 1993). From the average weight of the cows, these doses correspond to and 0.74 mg/kg per day. Milk was collected on days 1, 3, 5, and 7. Milk samples were injected onto a C-18 Sep-Pak and the fraction containing was concentrated and analysed on a TSK-gel ODS-80 HPLC column eluted with acetonitrile/water (7:3) with UV detection at 254 nm. The limit of determination was 0.02 mg/kg. There were no detectable residues in any of the milk samples.

34 417 It was reported that a feeding study was in progress in the USA in which groups of four cows had been dosed with the equivalent of 0, 6, 18, and 60 ppm of in the diet. Residues of and the main metabolites identified in the goat metabolism study were being determined in the milk, liver, muscle, kidney and fat. No poultry feeding study was reported. Most of the crops for which registration of has been approved or is expected do not produce feed components for poultry. An exception is cotton, from which cotton seed meal can be used, but no data from this crop were provided. FATE OF RESIDUES IN STORAGE AND PROCESSING In storage No data were provided. In processing Processing studies have been conducted on apples, grapes and tea. Apples. Washed apples from two trials in Germany at a two-fold rate were processed into juice and purée on a houshold scale (Raquet et al., 1993). Sample were analysed by GLC with an LOD of 0.01 mg/kg for juice and washings and 0.02 mg/kg for fruit. The aqueous washings showed no residues above 0.02 mg/kg. The peel obtained during the production of purée was not analysed. Pomace from the production of juice showed slightly higher residues than those in the original fruit. The results are shown in Table 39. Apples from other German trials (Brusche and Holzwarth, 1995) were processed to purée and juice. The procedures are shown in Figures 9 and 10. After the addition of 0.5 l water per kg fruit, the fruit was boiled for 20 minutes and sieved. The fractions obtained were washed fruit, washings, peels and pips, and purée (apple sauce). For the preparation of juice, cut apples were pressed in a juice extractor without prior heating. The crude juice was then filtered, poured into glass bottles, and pasteurized for 25 minutes at 75ºC. The low concentration of in the washings indicates that washing does not substantially reduce the residues in the fruit. About 40-60% of the residues in the harvested apples remained in the wet pomace or peels and pips. Table 39. Residues of in apples and processed fractions. Country, year kg ai/ha PHI, days Unwashed fruit Washed fruit Residue, mg/kg (Ratio to residue in unwashed fruit) Wet pomace Purée Washings Juice Reference Germany < Raquet, (0.63) (1.4) (0.25) (0.13) Germany <0.01 <0.01 Raquet, 1993