Toxicity is the second studio album by the American heavy metal band System of a Down, released on September 4, 2001, by American Recordings and Columbia Records. Expanding on their 1998 eponymous debut album, Toxicity incorporates more melody, harmonies, and singing than the band's first album. Categorized primarily as alternative metal and nu metal, the album features elements of multiple genres, including folk, progressive rock, jazz, and Armenian and Greek music, including prominent use of instruments like the sitar, banjo, keyboards, and piano. It contains a wide array of political and non-political themes, such as mass incarceration, the CIA, the environment, police brutality, drug addiction, scientific reductionism, and groupies.

Toxicity was recorded at Cello Studios in Hollywood, California. Over 30 songs were recorded, but the band narrowed the number of songs on the album to 14. The album peaked at number one on both the Billboard 200 and the Canadian Albums Chart, selling 220,000 copies in its first week of release. It was certified sextuple platinum by the Recording Industry Association of America (RIAA) in July 2022, signifying at least six million copies sold in the United States. All of Toxicity's singles reached the Billboard Hot 100. The final single, "Aerials", went to number one on both the Mainstream Rock Tracks and the Modern Rock Tracks charts. Toxicity received highly positive ratings and reviews from critics, among them perfect ratings from AllMusic, Kerrang!, and Blabbermouth.net. Many critics praised the album's sound and innovation, and it ranked on multiple "best albums" lists.

The promotional shows for Toxicity resulted in a number of controversial incidents. A six-hour riot ensued at a free concert in Hollywood the day before the album's release as a result of the show's cancellation due to an overcrowded show; the crowd in attendance was estimated to be at least twice the size that was expected. Another scheduled System of a Down performance was canceled to prevent a similar riot. The band then toured with Slipknot on the Pledge of Allegiance Tour, and bassist Shavo Odadjian was harassed, racially profiled, and physically beaten by guards when he tried to enter backstage at a concert in October 2001.

Name	Status	Rating	Review
serge		3.5/5 stars
Jeromium		3.5/5 stars