Microbiological contamination purified water

The pharmacopoeias deal with ingredient water of two types. Purified Water and Water for Injection. The principal difference in biological quality between the two types of water is that Water for Injection is specified to be pyrogen-free (less than 0.25 Eu of bacterial endotoxin per mL). Only water of Water for Injection quality may be used to dissolve, dilute, or compound parenteral products, because endotoxins may pass through 0.22 pm sterilizing filters. Control of bacterial endotoxins is achieved in the first instance through control of microbiological contamination. 

The use of purified water is recommended to keep the initial contamination low and thereby to hold the Ph. Eur. requirements for microbiological quality of non-sterile pharmaceutical preparations. The requirements of the chemical and microbiological purity of purified water are well defined, see Sect. 23.3.1. The concentration of ions in purified water is low, which is an advantage as they may catalyse degradation of active substances and excipients and form complexes with active substances and excipients. 

Redipacs are produced under GMP conditions. They are practically free from dust particles and have a good microbiological quality after production. Redipacs are not supplied sterile. When the preparation cannot be sterilised in the Redipacs, the Redipacs should be sterilised empty before use. When the Redipacs have become contaminated with dust particles, for example during pre-process handling, they should be flushed several times with purified water and dried if they are not immediately filled. 

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