Using duplex-consensus sequencing technology, we recently identified the characteristic high-resolution mutational spectrum of the liver carcinogen aflatoxin B₁ in a mouse model, many months before aflatoxin-induced tumors are detectable. The diagnostic power of this spectrum is then demonstrated by accurately identifying, among the sequenced human liver tumors, the subset of cancers associated with aflatoxin B₁ exposure. Keywords: Duplex sequencing; HCC; hepatocellular carcinoma; mutagenesis; mutational signature; mycotoxin