Irradiation to decontaminate herbs and spices 71
of radiation-processed foods have been studied in great detail (WHO, 1994; Diehl,
1997). These include:
∑ possibility of induced radioactivity
∑ microbiological safety
∑ safety of chemical changes
∑ nutritional adequacy
∑ animal feeding
∑ human trials.
At the energies of the gamma rays from Cobalt-60 (1.3 MeV) and those recommended
for X-rays (5 MeV) and accelerated electrons (10 MeV), no induced radioactivity has
been detected. The microbiological aspects of radiation-processed foods have been
studied in detail. None of these studies have indicated that foods preserved by radiation
pose any special problems in relation to microflora. It has been found that there is no
unique radiolytic product formed and free radicals in the system disappear depending
on the nature of the commodity and its post-irradiation storage and treatment. In fact,
the chemical differences between radiation-processed foods and non-irradiated foods
are too small to be detected easily. Though the rough composition of the food remains
largely unchanged, some losses in vitamins may be encountered. However, these
losses are often minor and could be made up from other sources.
Animal feeding studies have been the most time-consuming and expensive feature
of wholesomeness testing of irradiated foods. None of the short- or long-term feeding
studies, as well as the mutagen testing studies conducted with several irradiated
foods in several species of laboratory animals, has shown any adverse effect on these
animals. Similarly, no adverse effects have been found in human volunteers fed
irradiated food (WHO, 1994).
3.5 International approval.....................................................................
In 1980 a joint FAO/IAEA/WHO Expert Committee on Food Irradiation (JECFI)
reviewed the extensive data on wholesomeness collected up to that time and concluded
that irradiation of any commodity up to an overall dose of 10 kGy presents no
toxicological hazards and introduces no special nutritional or microbiological problems.
An expert group constituted by WHO in 1994 once again reviewed the wholesomeness
data available till then and validated the earlier conclusion of JECFI (WHO, 1994).
In 1997 a joint FAO/IAEA/FAO Study Group constituted by WHO affirmed the
safety of food irradiated to doses above 10 kGy (WHO, 1999). In view of this
recommendation the Codex Committee on Food Standards of The Codex Alimentarius
Commission has also revised the Codex General Standard for Irradiated Foods that
now allows use of doses higher than 10 kGy in case of a technological need. In this
context it may be noted that the USFDA has approved a dose of 30 kGy for sterilization
of spices, herbs and vegetable seasonings.
3.6 SPS application to boost international trade.................................
One of the major problems of international trade in spices and herbs is the presence
of exotic insect pests and microbes. This invites quarantine restrictions and hinders