Skip to main content
ARS Home » Research » Publications at this Location » Publication #261458

Title: Phytosanitary applications of irradiation

Author
item Hallman, Guy

Submitted to: Comprehensive Reviews in Food Science and Food Safety
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/17/2010
Publication Date: 2/1/2011
Citation: Hallman, G.J. 2011. Phytosanitary applications of irradiation. Comprehensive Reviews in Food Science and Food Safety. 10:143-151.

Interpretive Summary: Quarantine treatments are used to kill quarantine pests in agricultural produce so that it can be traded. Irradiation is a promising quarantine treatment that is increasing in use throughout the world. Almost 19,000 tons of sweet potatoes and several fruits are irradiated each year in six countries, including the United States, to control various plant quarantine pests, such as fruit flies. Advantages of irradiation compared with other quarantine treatments include its greater tolerance by fresh fruits, the ability to treat fruit in the final packaging, in pallet loads, and no pesticide residues. Disadvantages include lack of acceptance by organic growers and limited availability of the technology. A technological disadvantage is lack of an independent check on efficacy of the treatment because live pests may be found when the produce is inspected. With all other quarantine treatment the pests die shortly after treatment. However, this disadvantage does not hamper the use of irradiation by exporters, but makes the treatment more difficult to develop and regulate. Challenges to the increased use of irradiation are the cost because its commercial use has not yet reached an optimum economy of scale, lack of facilities, lack of approved treatments for some quarantine pests, and concern about irradiation by key commercial decision makers (packers, shippers and retailers). Methods for solving these problems are illuminated.

Technical Abstract: Phytosanitary treatments are used to disinfest agricultural commodities of quarantine pests so the commodities can be shipped across quarantine barriers to trade. Ionizing irradiation is a promising treatment that is increasing in use. Almost 19,000 tons of sweet potatoes and several fruits, plus a small amount of curry leaf, are irradiated each year in six countries, including the United States, to control a number of plant quarantine pests. Advantages over other treatments include tolerance by most fresh commodities, ability to treat in the final packaging, in pallet loads, and lack of pesticide residues. Disadvantages include lack of acceptance by organic industries and logistical bottlenecks resulting from current limited availability of the technology. A regulatory disadvantage is lack of an independent verification of treatment efficacy because pests may be found alive during commodity inspection, although they will not complete development or reproduce. For all other phytosanitary treatments, the pests die shortly after the treatment is concluded. This disadvantage does not hamper its use by industry, but rather makes the treatment more difficult to develop and regulate. Challenges to increase the use of phytosanitary irradiation are costly because commercial use has not yet reached an optimum economy of scale, lack of facilities due to their cost and current inability to feasibly locate them in packing facilities, lack of approved treatments for some quarantine pests, and concern about the process by key decision makers (packers, shippers and retailers). Methods for surmounting these challenges are discussed.