The Health, Labor and Welfare Ministry is reviewing the minimum age for blood donors to make it possible for 16-year-olds and 17-year-olds to donate 400 ml -- the same amount as donors above 18.
Under current health ministry guidelines, people under 18 can donate only 200 ml of blood at a time. But the smaller amounts raise the risk of patients contracting fever and rashes due to blood-mixing, health officials say.
As a result, hospitals and clinics generally use the 400-ml donations first, which has raised the percentage of 200-ml donations thrown out after their expiration date that much higher.
Given these circumstances, the health ministry is looking to expand the number of people who can make 400-ml donations and extend the period during which the blood may be used.
Ministry officials have set up an expert team to look into the matter and collected information from overseas to analyze the effect of 400-ml donations on the health of 16-year-old and 17-year-old donors.
They are also discussing extending the upper age limit for blood donors, which is currently set at 69.
The ministry hopes to draw up a conclusion by the end of the fiscal year.
According to the Japanese Red Cross, 1.54 million people made 200-ml donations and 2.73 million made 400-ml donations last year.
Red platelets retrieved from the donated blood and manufactured into transfusion-ready solutions are considered effective for up to 21 days, after which they are discarded.
Last year, 11.4 percent of the 200-ml donations were discarded, compared with 3.9 percent of the 400-ml donations.