PESTICIDE RESIDUES IN FOOD - 1980
Sponsored jointly by FAO and WHO
EVALUATIONS 1980
Joint meeting of the
FAO Panel of Experts on Pesticide Residues
in Food and the Environment
and the
WHO Expert Group on Pesticide Residues
Rome, 6-15 October 1980
SEC - BUTYLAMINE
Explanation
The Meeting considered a request from the 12th Session of the Codex
Committee on Pesticide Residues (FAO/WHO 1980) to re-evaluate the
levels in dried citrus pulp and citrus molasses in the light of
additional data provided by governments, with a view to revising
the MRLs on those commodities, if appropriate.
RESIDUES IN FOOD
USE PATTERN
Post-harvest treatments
Information was received from Australia on post-harvest uses of
sec-butylamine on citrus fruits, pome fruits and bananas. The
usual treatments consist of (1) 0.5% bulk bin dip of citrus and
pome fruits, (2) 1% dip of bananas packaged in wooden boxes, (3) 1%
flood of citrus fruits and bananas on the packing line, and (4) a
combined 0.5% dip and 1% flood of citrus fruits (Singh, G., et
al., 1979).
In the United States the registered label directions for use on
citrus fruits (post-harvest) are: apply a single dip or drench of
either a 0.5% or a 1% aqueous solution. Alternately a single spray
application of a 2% aqueous solution to cleaned fruit followed by
drying may be used. If necessary, the pH of the solutions is
adjusted to 8.0-9.0 by adding phosphoric acid (United States,
1980).
RESIDUES RESULTING FROM SUPERVISED TRIALS
Data from Australia on the results of supervised trials using
commercial post-harvest treatments on citrus fruits, pome fruits,
and bananas are summarized in Table 1. Residues on whole fruit
were highest from a bulk dip in a 0.5% solution of sec-butylamine
and reached the following values (mg/kg): oranges-4.54 (Valencia)
and 7.65 (Navel), tangors-6.10, mandarins-10.20, grapefruits-3.85
(Marsh) and 5.20 (Wheeny), lemons-10.70, apples-2.75 (Jonathan),
3.61 (Delicious) and 3.04 (Granny Smith), pears-11.20 (Packham's
Triumph) and 11.60 (Beurre Boss), bananas (Cavendish, 2 dips)-27.7
(whole ripe), 62.7 (Peel) and 1.06 (pulp) (Singh, G., et
al.,1979).
TABLE 1. Sec-butylamine residues on citrus fruits, pome fruits,
and bananas following post harvest treatments
Commodity Treatment Residue, mg/kg
(whole fruit)
Oranges Dip, 0.5% ai 4.54
(Valencia) Flood, 1% ai 0.88
Dip + flood 3.39
Oranges Dip, 0.5% ai 7.65
(Navel) Flood, 1% ai 2.25
Dip + flood 3.20
Tangor Dip, 0.5% ai 6.10
Flood, 1% ai 2.25
Dip + flood 2.85
Mandarin Dip, 0.5% ai 10.20
Flood, 1% ai 2.35
Dip + flood 3.35
Grapefruit Dip, 0.5%. ai 3.85
(Marsh) Flood, 1% ai 1.55
Dip + flood 1.55
Grapefruit Dip, 0.5% ai 5.20
(Wheeny) Flood, 1% ai 1.10
Dip + flood 2.50
Lemons Dip, 0.5% 10.70
Flood, 1% ai 1.14
Dip + flood 2.86
Apples
(Jonathan) Dip 2.75
(Delicious) Dip 3.61
(Granny Smith) Dip 3.04
Pears
(Packham's Truimph) Dip 11.20
(Beurre Bosc) Dip 11.60
Bananas
(Cavendish) 2 Dips 27.3 (green)
27.3 (ripe)
62.7 (peel only)
1.1 (pulp only)
TABLE 1. Continued...
Commodity Treatment Residue, mg/kg
(whole fruit)
Bananas 3 Floods 15.1 (green)
(Cavendish) cont'd 15.2 (ripe)
35.6 (peal only)
0.3 (pulp only)
Tests were conducted in the United States during 1967 and 1968 in
which oranges were treated with either a field drench of 1% ai, a line
drench of 1% ai, or both. Residues in the dried peel of navel oranges
ranged from 105 to 125 mg/kg from the 1% field drench, 23.0 to 23.4
mg/kg from the 1% line drench, and 56.4 to 66.3 mg/kg from the
combined treatment. The residue in dried cattle feed (peel) of
Valencia orange was 60.0 mg/kg while in molasses it was 14.8 mg/kg
(Table 2) ( United States, 1980).
In two separate experiments carried out during 1975, residues in the
dried pulp of treated (treatment unspecified) lemons and oranges were
93.0 mg/kg and 81.1 mg/kg respectively, while in the dried peel of
lemons and oranges treated by a commercial packing box or bin drench
of 1 or 2% ai they were 125 mg/kg and 50.1 mg/kg respectively (United
States, 1980).
Data from supervised trials carried out during 1965-1968 on residues
in by-products of oranges and grapefruit treated with 1 or 2% ai dips
or drenches were reviewed. Residues in molasses ranged from 13.1 to
27.8 mg/kg, while in dried pulp and meal the range was 16.2 to 48.3
mg/kg (FAO/WHO, 1977; United States, 1980).
TABLE 2. Residues of sec-butylamine in citrus fruits and products
following commercial treatments
Commodity Treatment Product Residues, mg/kg
Navel oranges Control Fresh (whole) 1.7, 2.6
Dried peel 4.3, 5.2
Field drench, Fresh (whole) 12.5, 16.0
1% ai Dried peel 105, 125
Line drench, Fresh (whole) 3.1, 3.4
1% ai Dried peel 23.0, 23.4
Both field & Fresh (whole) 8.0, 8.9
line drenches Dried peel 56.4, 66.3
Valencia oranges Drench, Wholefruit, before 15.4, 14.8, 12.6
wash
line, Wholefruit, after
wash 15.1, 12.4, 11.4
0.9% ai Fresh peel 31.2
Press peel 20.5, 23.1, 22.9, 20.3
Press liquor 3.2, 2.0
Conc. press liquid 13.2
Molasses 14.8
Dried cattle feed 60.0
Oil 1.3
Oil process
liquid 3.0
Navel oranges Control Fresh fruit
whole 0.86, 0.90
Air dried 10.1, 10.2
Vacuum dried 9.6, 11.0
Drench, Fresh fruit,
whole, 14.0, 14.5
line, Air dried 105.4, 108.6
1% Vacuum dried 92.8, 105.3
NATIONAL TOLERANCES REPORTED TO THE MEETING
It was noted that the correct national tolerance for residues of
sec-butylamine in citrus molasses and dried citrus pulp for cattle
feed given in the U.S. Code of Federal Regulations was 90 mg/kg, not
50 mg/kg as reported by the Meeting in 1975 (FAO/WHO, 1977; United
States, 1977).
EVALUATION
APPRAISAL
The meeting considered a request from the 12th Session of the Codex
Committee on Pesticide Residues to re-evaluate the levels in dried
citrus pulp and citrus molasses in the light of additional data
provided by governments, with a view to revising the MRLs on those
commodities, if appropriate.
Information was available giving approved use patterns for
post-harvest treatments on citrus, pome fruits and bananas along with
data from supervised trials on the same commodities. Residues on
whole fruit were highest from a bulk dip in a 0.5% solution of
sec-butylamine and reached the following values (mg/kg):
oranges-4.54 (Valencia) and 7.65 (Navel), tangors-6.10,
mandarins-10.20, grapefruits-3.85 (Marsh) and 5.20 (Wheeny),
lemons-10.70, apples-2.75 (Jonathan), 3.61 (Delicious) and 3.04
(Granny Smith), pears-11.20 (Packham's Triumph) and 11.60 (Beurre
Boss), bananas (Cavendish, 2 dips)-27.7 (whole ripe), 62.7 (peel) and
1.06 (pulp).
Information was available on registered post-harvest uses on citrus in
the USA and on the residues resulting from supervised trials on citrus
fruits and by-products used as cattle feed and pointing out that the
national tolerances reported for the United States in the 1975
Evaluation (FAO/WHO, 1976a) are in error.
Tests were carried out in 1967 in which oranges were treated with
either a field drench of 1% ai, a line drench of 1% ai, or both.
Residues in the dried peel of Navel oranges ranged from 105 to 125
mg/kg from the 1% field drench, 23.0 to 23.4 mg/kg from the 1% line
drench, and 56.4 to 66.3 mg/kg from the combined treatment. The
residue in dried cattle feed (peel) of Valencia oranges was 60.0 mg/kg
while in molasses it was 14.8 mg/kg.
In two separate experiments carried out during 1975, residues in the
dried pulp of treated (treatment unspecified) lemons and oranges were
93.0 mg/kg and 81.1 mg/kg respectively, while in the dried peel of
lemons and oranges treated by a commercial packing box or bin drench
of 1 or 2% ai they were 125 mg/kg and 50.1 mg/kg respectively.
Data from supervised trials carried out during 1965-1968 on residues
in citrus by-products produced from treatment of oranges and
grapefruit with 1 or 2% ai dips or drenches were reviewed. Residues
in molasses ranged from 13.1 to 27.8 mg/kg while in dried pulp and
meal the range was 16.2 to 48.3 mg/kg.
It was noted that from a copy of the U.S. Code of Federal Regulations,
April 1, 1977 revision, section 561.60, that the correct national
tolerance for residues of sec-butylamine in citrus molasses and
dried citrus pulp for cattle feed was 90 mg/kg.
From a consideration of all of the available data it was concluded
that the existing figure for the maximum residue limit of
sec-butylamine in dried citrus pulp should be increased to 100
mg/kg. The additional data on residues in pome fruits and bananas
were insufficient to support recommendations.
RECOMMENDATIONS OF RESIDUES LIMITS
It is recommended that the maximum residue limit for residues of
sec-butylamine in dried citrus pulp be increased from 50 mg/kg to
100 mg/kg. A maximum residue level of 50 mg/kg in citrus molasses is
unlikely to be exceeded and is retained as a maximum residue limit.
Commodity Maximum residue limit, mg/kg
Dried citrus pulp 100
Citrus molasses 50
REFERENCES
Singh, G., Rippony L.E., Gilbert, W.S. and Ahmad, N. Sec-butylamine
residues in citrus, pome fruits, and bananas from post-harvest
treatments. Aust. J. Exp. Agric. Anim. Husb. 19, 118-121.
United States. Collected unpublished reports and test data on residues
of sec-butylamine in citrus and citrus by-products, 1967-1975;
(1980).
United States. Code of Federal Regulations, 21, Food and Drugs, Parts
500 to 599, April 1, 1977 revision, section 561.60.