Biohazard is an American hardcore band formed in Brooklyn, New York City, in 1987. They are one of the earliest bands to fuse hardcore punk and heavy metal with elements of hip hop. The original lineup consisted of bassist/vocalist Evan Seinfeld, guitarist Bobby Hambel, and drummer Anthony Meo. Guitarist/vocalist Billy Graziadei joined soon after, and drummer Danny Schuler replaced Meo before the recording of their first album, thus solidifying the band's lineup from 1988 to 1995.

Evan Seinfeld is an American musician and former pornographic actor, writer and director. He is best known as the lead vocalist, bassist, and founding member of the hardcore/metal band Biohazard. Seinfeld left the band in May 2011 citing personal reasons, but rejoined in October 2022 after performing with several other acts.