UMUR "Purity Dilution" is the debut full-length studio album by US/UK grindcore act Defecation. The album was released through Nuclear Blast Records in 1989. Defecation was formed as a side-project by Righteous Pigs guitarist Mitch Harris (guitars, bass, vocals) and Napalm Death drummer Mick Harris (drums, vocals) in 1987. It was initially a one-off project, as Mitch Harris joined Napalm Death in late 1989, and both guys focused on that band (not for long though as Mick Harris soon left Napalm Death to form Scorn). Mitch Harris ressurected Defecation in the early years of the new millenium and released "Intention Surpassed" in 2003.

The music on "Purity Dilution" is Napalm Death influenced grindcore with the odd nod towards a punked version of old school death metal. The album was recorded and mixed in 29 hours and was co-produded by Danny Lilker (Anthrax, Nuclear Assault, Brutal Truth). It´s audible that the band probably didn´t have time to do more than a few takes of each track, because this is a very organic sounding and not always tight performance. On some tracks the vocalist sounds pretty commanding, delivering some convincing growling vocals, while he sounds strained and hoarse on other tracks, which is probably the consequence of having to record all the vocal tracks within a few hours.

The tracks feature both mid-paced heavy parts, faster punk rhythms, and furiously fast-paced blast beat sections. Despite the relatively varied rhythmic approach the material is a bit one-dimensional and not many tracks stand out from the others. The sound production is pretty raw, lo-fi, and parts of the production lacks punch. So upon conclusion "Purity Dilution" is quality wise a bit of a mixed bag. I admire the DIY approach of the project, but the outcome really isn´t the greatest or most distinct sounding grindcore release and a 2.5 (50%) rating is warranted.