TABLE 3.4 Typical Process Times for Mo-99 and Tc-99m Supply Chains

Process steps

Typical process times (hr)

U-235 target irradiation and cooling


(5–7 days)

Shipping and processing of target to extract Mo-99


Mo-99 packaged and shipped


Tc-99m generator prepared and packaged


Tc-99m generator shipped


Tc-99m generator used by hospital or radiopharmacy


(7–14 days)

ties to hospitals and radiopharmacies using both air and ground services. Perhaps the most striking characteristic of these supply chains is their time efficiency: Because of the short half-lives for Mo-99 and Tc-99m, the revenues that can be obtained from their sale depend on how quickly they can be distributed to users. Table 3.4 shows the typical times required to move Mo-99 and Tc-99m through their supply chains, which in some cases span continents. The elapsed time between the time the irradiated targets are delivered to the processing facility and delivery of a Tc-99m dose to a patient can be as little as 25–76 hours. Actual times depend on the shipping distances and availability and frequency of transportation.

Figure 3.5 provides a schematic representation of the supply chains for U.S. producers of Mo-99 and Tc-99m generators. As noted previously, there are two suppliers of Mo-99 to the United States: MDS Nordion and Mallinckrodt. There are also two technetium generator manufacturers in the United States: Mallinckrodt and Lantheus, located in Maryland Heights, Missouri, and Billerica, Massachusetts, respectively.

MDS-Nordion ships most of its Mo-99 from Canada to the United States by air charter to technetium generator manufacturers. It supplies its key customer Lantheus and also supplies some Mo-99 to Mallinckrodt. Lantheus supplies technetium generators to markets throughout North America. Mallinckrodt ships Mo-99 from its production facility in the Netherlands to its Maryland Heights, Missouri, facility by aircraft. Mallinckrodt has an in-house facility at Maryland Heights for preparing and shipping technetium generators. Technetium generators are shipped to radiopharmacies and hospitals across the United States, Canada, and Latin America. The generators are available in a number of different curie loadings, generally ranging from less than half a curie to about 20 curies.27


Under Department of Transportation regulations, technetium generators can be shipped by Federal Express if they contain fewer than 20 curies.

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