Biohazard formed in Brooklyn in 1988 and soon after released their first demo. The band consisted of founding members Billy Graziadei (vocals, guitar), Bobby Hambel (lead guitar) and Evan Seinfeld (vocals, bass). After the release of their second demo in 1989, drummer Anthony Meo left the band and drummer Danny Schuler replaced him. BIOHAZARD released their combined the urban sounds of hard-core, metal and rap with scorching lyrics describing the forces at work in our modern urban lives. With an impressive career spanning over 20 years with 10 albums (on both indie and major labels), the band sold over 5 million records. In 1990, Biohazard signed a recording contract with Maze Records. The band’s self-titled debut album was poorly promoted by the label and sold approximately 40,000 copies. The album’s subject matter revolved around Brooklyn, gang-wars, drugs, and violence.

In 1992, Biohazard signed with Roadrunner Records and released Urban Discipline, which gave the band national and worldwide attention in both the heavy metal and hardcore communities. The video for the song “Punishment” became the most played video in the history of MTV’s Headbanger’s Ball, and the album sold over one million copies. The band also began opening for larger acts such as Pantera, Suicidal Tendencies, House of Pain, Fishbone, and The Cro-Mags. In 1993, the hardcore rap group Onyx brought on Billy Graziadei for an alternate “Bionyx” version of their hit single “Slam” with Biohazard as their backup band. This led to a collaboration on the title track of the Judgment Night soundtrack. The soundtrack would go on to sell over two million copies in the United States. Months later, the band left Roadrunner Records and signed with Warner Bros. Records Inc. who released their third studio LP, State of the World Address. The album was produced by Ed Stasium in Los Angeles and contained the single “How It Is” featuring Sen Dog of Cypress Hill, for which a video was also shot. During their 1994 tour, the band made an appearance on the second stage at the Monsters of Rock festival held at Castle Donington. State of the World Address went on to sell over one million copies, and Rolling Stone magazine selected the Biohazard logo as the best logo of the year.

This was the last Biohazard album with Bobby Hambel, who left due to differences with the rest of the band. The band recorded their fourth studio album, Mata Leao, as a three piece in 1996. It was produced with the help of Dave Jerden. For the 1996-97 Mata Leao Tour, former Helmet guitarist Rob Echeverria joined the band. The band also played on the Ozzfest mainstage alongside Ozzy Osbourne, Slayer, Danzig, Fear Factory, and Sepultura. While touring Europe in support of the Mata Leao album, the band recorded their Hamburg, Germany, show for their first live album, No Holds Barred (Live in Europe), which was released in 1997 through their former label, Roadrunner Records. The band signed to Mercury Records and released their fifth studio album, New World Disorder, in 1999, once again with Ed Stasium as a producer.

The relationship with Mercury Records soured quickly as the band felt betrayed and misunderstood by the label. They severed their ties with the label amidst the merger of Mercury Records, Island Records, Def Jam Records, and Polygram into the Universal Music Group. The following year, Biohazard signed two new record deals with SPV/Steamhammer in Europe and Sanctuary Records for the remainder of the world. Despite the new record deals, the band took some personal time in order to work on other projects. Graziadei and Schuler also collaborated in transforming the band’s rehearsal Brooklyn studio into a digital recording studio, known as Rat Piss Studios and soon after changed the name to Underground Sound Studios. Re-investing into the band, Graziadei and Schuler honed their engineering and productions skills while recording and producing local acts and new Biohazard demos. The band then undertook the process of writing, recording, and producing their own music. Their studio work led to the band’s sixth studio album, Uncivilization, released in September 2001.

The album featured several guest appearances by members of bands such as Agnostic Front, Hatebreed, Pantera, Slipknot, Sepultura, Cypress Hill, Skarhead, and Type O Negative. Shortly after the release of Uncivilization, guitarist Leo Curley left the band and was replaced by former Nucleus member Carmine Vincent, who had previously toured with Biohazard as part of their road crew. The band had to cancel scheduled European festival dates when Carmine Vincent underwent major surgery. The band did manage to find a temporary guitarist, Scott Roberts, formerly of the Cro-Mags and the Spudmonsters, in time to join the Eastpak Resistance Tour with Agnostic Front, Hatebreed, Discipline, Death Threat, Born From Pain and All Boro Kings. Biohazard completed their seventh studio album in seventeen days; Kill Or Be Killed was released in 2003. While touring North America with Kittie, Brand New Sin and Eighteen Visions, Biohazard announced that Roberts would remain as their permanent lead guitarist. The tour was curtailed when it was announced that Seinfeld had fallen ill. With more downtime due to Seinfeld’s illness, Graziadei and Schuler collaborated to mix Life of Agony’s live comeback album, River Runs Again: Live 2003. Once Seinfeld was healthy again, the band toured Japan and North America, headlining over bands such as Hatebreed, Agnostic Front, Throwdown, and Full Blown Chaos.

By the end of 2003, the band had begun recording its eighth studio album, Means To An End. The completed album was lost in a studio disaster, forcing the band to completely re-record the album, which was finally released in August 2005. In October 2004, Graziadei announced that Means To An End had been the final Biohazard album and that he would continue playing with his new band Suicide City as his main focus. One month later, on the Biohazard website, it was announced that there would in fact be a 2005 Biohazard tour. On December 15, 2005, Seinfeld and Graziadei participated in the Roadrunner United conglomerate event at the Nokia Theater in New York for an all-star event. The show opened with Biohazard’s “Punishment,” performed by Seinfeld, Graziadei, Sepultura’s Andreas Kisser, former Fear Factory member Dino Cazares, and Slipknot’s Joey Jordison. Graziadei and Schuler relocated their recording studio to South Amboy, New Jersey and renamed it Underground Sound Studios. The studio was renovated to include a live room with 20-foot (6.1 m) ceilings and 4,000 square feet (370 m2) of studio space. After Schuler’s departure from the studio business, Graziadei relocated the studio to Los Angeles and changed the name to Firewater Studios. In January 2008, the classic lineup of Evan Seinfeld, Billy Graziadei, Danny Schuler and Bobby Hambel made the announcement that rehearsals had begun for a 2008 summer tour to commemorate the band’s 20th anniversary. They toured Australia and New Zealand in April with Chimaira, Throwdown, Bloodsimple and headliners Korn to celebrate their newly declared reunion. The band also took part in Persistence Tour 2009, and announced at one of their shows that they were working on a new record. Biohazard brought in producer Toby Wright to work on the album and after several months at Graziadei’s Firewater Studios in Los Angeles, the band completed their recording sessions. In June 2011, Biohazard announced that Evan Seinfeld had quit the band and Scott Roberts returned to replace Seinfeld for two UK dates but no decision regarding a permanent replacement was made. In January 2012, the band decided that Scott Roberts would remain with the band as a permanent member. The new album, Reborn In Defiance, was released worldwide, with the exception of North America, on January 20, 2012 through the Nuclear Blast label. In support of the album, Biohazard embarked on a short co-headlining tour of Europe with Suicidal Tendencies in the latter half of January 2012. After touring the world in support of Reborn in Defiance, the band entered the studio to work on a new release and after a falling out, Roberts departed the band.

Biohazard remains as it’s core founding members of Graziadei, Shuler and Hambel. Graziadei has since ventured off onto a solo career as BillyBio and teamed up with Cypress Hill frontman Sendog to start Powerflo. Both groups are working on their second releases due out late 2021 and early 2022.