Recent sessions of the CCPR have:
(i) Questioned whether prunes should be included with the
recommended MRL for plums (1977);
(ii) Asked the JMPR to review its recommended 2 mg/kg level for
lettuce in the light of USA evidence that 3 mg/kg would seem
more appropriate (1977);
(iii) Questioned the JMPR proposed level of 0.5 mg/kg for tomatoes on
the grounds that it was based on only two trials in one country
involving exposures due to the use of smoke tablets in a
glasshouse; whereas current usages may require limits up to 3
RESIDUES AND THEIR EVALUATION
Plums and `Prunes'
After reviewing information previously considered, the meeting was not
aware of any data relating specifically to residues in dried plums of
the kind widely marketed and commonly referred to as `prunes' in
English-speaking countries. Until such data becomes available
therefore, it was recommended that the commodity `prunes' should not
be covered by the recommendation for plums.
In the absence of a submission of the new data referred to at the 1977
Session of the CCPR, the data considered at the 1975 and 1977 JMPR
meetings were re-examined. These data clearly support a limit of 2
mg/kg for lettuce, even if a preharvest interval of 5 days is selected
instead of one for 7 days. Therefore, the meeting decided not to
alter its recommendation.
The suggested figure of 3 mg/kg arises from a registered use (U.S.A.)
which permits lindane smokes in tomato greenhouses at the rate of 1 g
(a.i.) per 100 cu. ft. with one day pre-harvest interval. Residues
found in tomatoes one day after 15 hour exposure to smoke were 0.9 and
1.4 mg/kg and three days later were 0.9 and 1.3 mg/kg (Smith, 1961).
The limited data together with data considered at the 1977 Meeting and
country information (Cummings, 1979) on changing sources of winter
vegetables and changes in use patterns for lindane in the USA, make it
possible to increase the recommended limit to 2 mg/kg for lindane on
Questions arising from the 1977 and 1979 Sessions of the CCPR referred
to the meeting were: (1) whether prunes should be included in the
recommendations for plums; (2) whether a limit of 3 mg/kg for lettuce
would be more appropriate than 2 mg/kg, and (3) whether a limit of 3
mg/kg for greenhouse tomatoes might be more appropriate than 0.5
On (1) the meeting notes that none of its recommendations for lindane
in plums include prunes and recommends that prunes should be excluded
until such time as residue data are available to support a limit.
On (2) the JMPR examined the data summarized in its 1975 and 1977
monographs and concluded that its recommended limit of 2 mg/kg on
lettuce is supported. National governments with differing data
derived from supervised trials are urged to make it available to the
On (3) the 1979 JMPR considered new residue data and use pattern
information on greenhouse tomatoes and concluded that the limit for
tomatoes should be increased to 2 mg/kg with a one-day preharvest
interval. The analytical distinction between 2 mg/kg and 3 mg/kg is
not considered to be of significance.
The previous maximum residue limit for lindane in or on tomatoes is
amended as follows:
Commodity Maximum Preharvest interval on which
residue the recommendation is
limit (mg/kg) based (days)
Tomatoes 2 (Greenhouse) 1
FURTHER WORK OR INFORMATION
1. Details of the results of supervised trials on the use of lindane
on greenhouse lettuce.
2. Results of supervised trials on the residues of lindane in prunes
made from treated plums.
Cummings, J.G. Private communication (1979).
Smith, F.G. Studies on Residues from Lindane Smokes on Greenhouse
Vegetables, US Department of Agriculture Report, 1961.