(In this version of February 8th’s story, NorthStar corrects date by which it will supply 10 percent of U.S. market to late 2018, not late 2019.)

WASHINGTON (Reuters) - The U.S. federal government on Thursday approved a device made by a private company in Wisconsin that will allow the first domestic production of a medical imaging isotope in 25 years, a move the government said would enhance national security by reducing the need to transport weapons-grade uranium.

The Food and Drug Administration granted the approval to NorthStar Medical Radioisotopes, which said it would begin delivering systems to make technetium-99 within weeks.

Technetium-99 is the most common isotope in medicine and is used in 40,000 procedures a day in the United States, the world’s top consumer of radioisotopes for medical imaging to help detect cancer and heart problems.

However, U.S. consumers have long had to depend on a complicated and risky supply chain for the materials.

The current process involves shipping weapons-grade, or highly enriched, uranium from the United States to research reactors in Australia, South Africa and Europe where it is irradiated to make molybdenum-99, which decays into technetium-99.

The molybdenum-99 has to be rushed back to U.S. hospitals because of the speed of the rate of decay.

“This is a win for our national security,” said Peter Hanlon, an official with the National Nuclear Security Administration (NNSA) office of material management and minimization.

Critics of the current system say shipping highly enriched uranium leaves it vulnerable to being stolen by militant groups who could use it to make a dirty bomb.

The NNSA has agreed to fund three projects with $25 million each to produce moly-99 not based on highly-enriched uranium, including ones by SHINE Medical Technologies, General Atomics, and NorthStar.

The United States has suffered shortages of imaging isotopes, the most severe one in 2010. The risk of shortages increased when Canada shut a research reactor in 2016.

FDA Commissioner Scott Gottlieb said supply disruptions, and even the threat of disruptions, have pushed clinicians to shift to alternative isotopes “that may be more expensive or may expose patients to higher doses of radiation.”

NorthStar said that by late 2018 it expects to have the ability to supply around 10 percent of the U.S. market.

That would “very significantly mitigate the impact of the type of shortages we have been seeing recently,” a company official said. It plans to ramp-up production capacity over the next few years in a bid to meet two-thirds of U.S. demand.