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Water for Pharmaceutical Use Part 1: Introduction and treatment. Supplementary Training Modules on Good Manufacturing Practice. Objectives Introduction to Water for Pharmaceutical Us e Review WHO GMP guidance S ources and types of water for pharmaceutical use
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Water for Pharmaceutical UsePart 1: Introduction and treatment Supplementary Training Modules on Good Manufacturing Practice
Objectives • Introduction to Water for Pharmaceutical Use • Review WHO GMP guidance • Sources and types of water for pharmaceutical use • Storage of bulk, untreated raw water • Pre-treatment of water
Principles (1) • Like any starting material, water must conform to Good Manufacturing Practice norms • It must be “potable” and comply with WHO Guidelines for drinking-water quality
Principles (2) • Potential for microbial growth • Systems must be properly validated • Water for parenteral use could be contaminated with pyrogens or endotoxins • Specifications and periodic testing is required Annex 5, 7.2.4 Excipients,
Types of water used in pharmaceutical processes • Purified water • Water for Injections – PFW & WFI • Softened Water • Water for Final Rinse • Pure, or clean Steam • Water for cooling Autoclaves
Why purify raw water? • Although reasonably pure, it is always variable • Seasonal variations may occur in water • Some regions have very poor quality water • Must remove impurities to prevent productcontamination. • Controlmicrobesto avoid contaminating products
Contaminants of water (1) • There is no pure water in nature, as it can contain up to 90 possible unacceptable contaminants • Contaminant groups: • Inorganic compounds • Organic compounds • Solids • Gases • Micro-organisms
Contaminants of water (2) Treatment depends on water’s chemistry and contaminants, influenced by: • Rainfall • Erosion • Pollution • Dissolution • Evaporation • Sedimentation • Decomposition
Contaminants of water (3) Problem minerals • Calcium and magnesium • Iron and manganese • Silicates • Carbon dioxide • Hydrogen sulfide • Phosphates
Contaminants of water (4) Further problem minerals • Copper • Aluminium • Heavy metals • Arsenic, lead, cadmium • Nitrates
Contaminants of water (5) Micro-organisms – Biofilm • Algae • Protozoa • Cryptosporidium • Giardia • Bacteria • Pseudomonas • Gram negative, non-fermenting bacteria • Escherichia coli and coliforms
Biofilm formation • Free swimming aquatic bacteria use polymucosaccharides to colonise surfaces • Complex communities evolve which shed micro-colonies and bacteria
Turbidity • Silt, clay, and suspended material cause turbidity • Small particles include "colloids" • Removal ofcolloids is usually the first step in water treatment
Water hardness classification mg/L or ppm as CaCO3 Soft 0-60 Moderate 61-120 Hard 121-180 Very Hard > 180 Water hardness
Source of raw water • Rainwater • Surface or ground water • Well or borehole • Municipal or civil – “tap water” • Purchased in bulk
Well water • Inspect exposed parts of the well • Depth of well Check: • Nearby septic systems • Hazardous materials usage (pesticides, fertilizers, etc) • “Potability” • Well maintenance
Raw water storage • May be required prior to pre-treatment according to local circumstances • Check material of construction • Concrete, steel are acceptable but check corrosion • Plastics or plastic linings may leach • Check cover • To keep out insects, birds and animals • Check disinfection practices
WHO water treatment guidance The following should be monitored • Sources of water • Treatment procedures • Water treatment equipment • Treated water tests • Monitoring records required Annex 1, 17.42
Pre-treatment steps • Primary filtration and multi-media filter • Coagulation or flocculation • Desalination • Softening
Chlorine removal Activated-carbon (AC) filtration or bisulphite • AC removes chlorine but bacteria can then grow • AC filtration can remove organic impurities • Bisulphite leaves sulphate residues but is anti-microbial
Pretreatment – schematic drawing float operated valve To water softener & DI plant activated carbon filter excess water recycled from deioniser sand filter air filter spray ball Water is kept circulating raw water in break tank cartridge filter 5 micrometers centrifugal pump air break to drain « S” trap to sewer
"soft" water to deioniser "hard" water in • zeolite water softener • exchanges • Ca and Mg for Na Water Softener – schematic drawing by pass valve brine and salt tank brine drain
Water pre-treatment complex External raw water storage Pretreatment room