National Toxicology Program

• Primary Uses or Exposures: HCV is an RNA-enveloped virus. The major risk factor for infection is illegal intravenous drug use, which accounts for 60% of acute HCV infections in adults. Since the screening of blood and blood products for HCV began in the 1990s, blood transfusion has accounted for only a small percentage of adult HCV cases (about 3%). Other routes of transmission include sexual, perinatal (from mother to infant at birth), familial (at low rates), and through health-care practices, including transmission by contaminated equipment or supplies, from patient to patient (at low rates), and through occupational exposure (at low rates).
• Nominated by: NIEHS
• Basis for Nomination: Classified by IARC¹ as carcinogenic to humans based on sufficient evidence in humans
• Current Status: Listed in the RoC as known to be a human carcinogen since the 11th RoC (2004)

¹ International Agency For Research On Cancer (IARC)