PESTICIDE RESIDUES IN FOOD - 1983
Sponsored jointly by FAO and WHO
EVALUATIONS 1983
Data and recommendations of the joint meeting
of the FAO Panel of Experts on Pesticide Residues
in Food and the Environment and the
WHO Expert Group on Pesticide Residues
Geneva, 5 - 14 December 1983
Food and Agriculture Organization of the United Nations
Rome 1985
ETHEPHON
RESIDUES
Ethephon was evaluated by the Joint Meeting in 1977 and 1978
(FAO/WHO 1978b, 1979b)1, and as no acceptable daily intake (ADI) was
estimated, only guideline levels have been proposed. Information on
new use patterns from The Netherlands, and more residue data from
supervised trials in The Netherlands and Finland have been received
and are summarized in this monograph addendum.
RESIDUES IN FOOD AND THEIR EVALUATION
USE PATTERN
Ethephon is registered in The Netherlands for use on winter
barley, summer barley and winter rye to prevent lodging of straw. It
is used at application rates from 0.24 to 0.72 kg/ha. Treatment takes
place at stage 8-10.1 of the Fleekes-scale (The Netherlands 1982).
RESIDUES RESULTING FROM SUPERVISED TRIALS
Additional data were received from The Netherlands from
supervised trials on onions and from Finland from trials on Peppers,
tomatoes, blackcurrents, apples, rye and barley (The Netherlands 1982;
Finland 1982). Ethephon has not yet been registered for use in
Finland. The residue data are summarized in Table 1.
RESIDUES IN FOOD IN COMMERCE OR AT CONSUMPTION
Surveys were conducted in The Netherlands in 1982 on residues of
ethephon in apples, pears and tomatoes. Of 61 samples analysed, ten
samples of apples and five of tomatoes contained residues, which were
all below the national residues limits in The Netherlands (The
Netherlands 1982).
1 See Annex 2 for FAO and WHO documentation.
Table 1 Residues of Ethephon from Supervised Trials
Country and Application rate Interval after last Residue
crop (a.i.) treatment (days) (mg/kg)1
Netherlands
Onion 0.96-1.92 kg/ha 480 g/l 21 0.1-0.35 (3)
Finland
Bellpepper 0.1 mg/plant (greenhouse) 8-15 0.1-0.2 (2)
Tomato 25 mg/plant 12-36 1.0-2.0 (2)
50 mg/plant 10 1.6 (1)
2 x 50 mg/plant 7 3.1 (1)
100 mg/plant (greenhouse) 9 2.0-3.4 (2)
160 mg/plant (greenhouse) 10 2.4 (1)
40 mg/m2 (greenhouse) 10 3.2 (1)
2x12.5 mg/m3 (greenhouse,sprayed) 12-14 0.02 (1)
2x25 mg/m3 (greenhouse, sprayed) 12-14 0.05 (1)
2x50 mg/m3 (greenhouse, sprayed) 12-14 0.15 (1)
Black currents 150 mg/bush 7 1.0 (1)
Apple 2.5 g/tree 16 0.3 (1)
6.3 g/tree 16 5.4 (1)
Winter rye 0.3 kg/ha 75-82 grains:
(+ mepiquat 0.6 ka/ha) <0.01-0.1 (3)
1.4 kg/ha 79-84 0.07-0.4 (2)
2.5 kg/ha 75-76 0.3-0.5 (2)
Summer barley 0.16 kg/ha 66-73 <0.02 (2)
(+ mepiquat 0.31 kg/ha)
0.23 kg/ha
(+ mepiquat 0.46 kg/ha) 66-75 <0.02-0.02 (2)
0.3 kg/ha
(+ mepiquat 0.6 kg/ha) 49-61 <0.01 (2)
0. 24 kg/ha 66-73 <0.02 (2)
0.48 kg/ha 66-73 <0.02 (2)
1.0 kg/ha 66-73 <0.02 (2)
1 See Annex 2 for FAO and WHO documentation.
2 Number of samples analysed is given in parentheses.
NATIONAL MAXIMUM RESIDUE LIMITS
The following maximum residue limits (MRLs) in The Netherlands
were reported to the Meeting:
Crop MRL (mg/kg)
Apple 2
Cherry 1
Tomato 3
Onion 0.5
Grains 0.5
Others 0-0.1
APPRAISAL
New information from The Netherlands was available on use
patterns for ethephon in cereals and on residue levels found in
commerce.
New residue data were received from supervised trials on onions
in The Netherlands and from trials on apples, tomatoes and bell
peppers in Finland. All data supported the existing guideline levels.
Residue data from trials on barley and rye were also received
from Finland, but as no registration has yet taken place in that
country, there was no basis on which to estimate maximum residue
levels.
REFERENCES - RESIDUES
The Netherlands Report on residues of ethephon in apples, pears and
1982 tomatoes produced in The Netherlands. Keuringsdienst v.
Waren, Utrecht, 1982:IR/45/11/82/R103).
Finland Report from the National Board of Trade and Consumer
1982 Interests, Helsinki. (Unpublished)