Some people joke that they "give blood" for their company, a metaphor for how hard they work. But nowadays, with high unemployment rates there are fewer workers available to literally give their blood to the American Red Cross and other organizations at on-the-job drives.

Corporate blood drives help to bolster local blood supplies across the country, but as the U.S. unemployment rate hit 9.7 percent last month, blood banks are starting to feel the pinch, reports the Associated Press.

"We are seeing a direct effect of the recession," Toni Gould, a spokesperson for Michigan Community Blood Centers, told the AP. "So many businesses and factories are closing, and they accounted for a large share of mobile drives." The group has seen a 15 to 20 percent decrease in donations for the summer as the state's unemployment rate has crept up to 15.6 percent.

Some areas are starting to import blood as they see their reserves drying up. A recent blood drive at an Anheuser-Busch brewery in Jacksonville, Fla., yielded about 45 units of blood, where the city's blood bank could previously count on the company for some 300 units. As workforces decrease and current employees feel pressure to work harder, the number of volunteer donors has dropped for many drives. "Some people were like, 'And now you want my blood?'" Dan Eberts, a spokesperson for Florida Blood Services told the wire service. Some companies have started canceling blood drives altogether.

Despite gloomy outlooks in some places, the American Red Cross maintains that nationally, blood supplies are stable for now. "We're not in a crisis situation," Nick Samaniego, a spokesperson for the organization, told the wire service. "But we're not exactly where we want to be."

Some experts note that the drop could also be attributed to the summer season, when many are on vacation and some popular drive sites, such as schools, are closed. Others suggest that a portion of the decline might be because more people are now ineligible to donate—based on exotic travel or a recent tattoo. According to the American Red Cross, less than 38 percent of the U.S. population would be allowed to donate at any given time, due to ever-more stringent donor restrictions from the Red Cross.

At the other end of the donation spectrum, paid plasma donation have been rising for reasons that might also be related to the economy. Plasma donation companies will pay something to the tune of $200 a month to someone who gives plasma twice a week; plasma donations were up to 18.8 million in 2008. The American Red Cross reported about 15 million blood donations in 2001 (the most recent year of available data).

Image courtesy of Jerry via Flickr