PESTICIDE RESIDUES IN FOOD - 1979
Sponsored jointly by FAO and WHO
Joint meeting of the
FAO Panel of Experts on Pesticide Residues
in Food and the Environment
WHO Expert Group on Pesticide Residues
Geneva, 3-12 December 1979
Carbaryl has been evaluated on a number of occasions. An ADI has
been established and maximum residue limits for carbaryl residues
in commodities have been recommended. New Zealand submitted data
in support of a request that the Meeting propose a maximum residue
limit for carbaryl on kiwi fruit.
RESIDUES IN FOOD AND THEIR EVALUATION
Kiwi fruit (Actinidia chinensis) is now the second largest
horticultural product exported from New Zealand, the value being in
excess of US $20 million annually. The fruit is, like most
horticultural crops, subject to attack by a number of pests and
diseases and to meet plant health requirements of countries
importing New Zealand produced kiwi fruit it is necessary to spray
Carbaryl is applied 5 times during the growing season, 4 times in
combination with diazinon and then once alone in early April. The
additional application is needed because of the short life of the
chemical. The time interval between the last treatment and harvest
is of the order of 21 days. The rate recommended for the first
four sprayings is 80 g ai/100 L with 120 g ai/100L for the last
spray, giving a total of 9.9 kg/ha in the season.
RESIDUES RESULTING FROM SUPERVISED TRIALS
No replicated trial data are available but some data following
grower use in 1978 show that residues are not likely to exceed 10
mg/kg on the whole fruit.
A summary of this information is included in Table 1.
Table 1. Carbaryl residues on kiwi fruit.
Number of Rate per Residue on
Applications Application Kg a.i./ha Interval whole commodity
ai g/100 L (days) (mg/kg)
6 120 16.12 delayed 2.0
1 120 2.7 13 3.1
4 220 9.3 9 7.4
2 270/400 9.9 9 5.1
Further monitoring indicated that when the interval between last
application and harvest was as little as 9 days the residues ranged
from 5 to 7.5 mg/kg carbaryl on total fruit. On the basis of this
experience, and subsequent to 1978 the pre-harvest interval was
extended to 21 days but the number of applications was increased as
Because of the hairy nature of the skin spray residues are retained on
the fruit more than would be the case if the skin was smooth.
However, in the case of non-systemic insecticides, trial data have
shown that 90% of the residue remains on the skin. The skin, being
hairy, is relatively unpalatable and is generally discarded.
Carbaryl is used in the regular spray programme for the control of
pests of kiwi fruit. Data supplied by New Zealand, indicates that
following approved uses, involving up to 5 sprays, the last within 21
days of harvest, carbaryl residues on the whole fruit could range up
to 10 mg/kg.
These data provide a basis for recommending a maximum residue limit on
The following additional maximum residue limit is recommended for
kiwi fruit 10 mg/kg
(This is based on a 21 day pre-harvest interval)