Purified water treatment

Purified Water Treatment Hydrology

Overview

• Water is essential in the pharmaceutical industry for various applications, including:

  • Raw material for drug products.

  • Ingredient and solvent in formulation.

  • Cleaning and rinsing lab equipment.

  • Analytical reagent in quality control.

Importance of Water Purity

• Water used in pharmaceuticals must meet standards from USP or EP.

• Contaminated water can compromise drug safety and efficacy.

• Regular quality control tests are necessary to ensure compliance.

Types of Water in Pharmaceuticals

• USP Classifications:

  1. Purified Water (PW)

  2. Water for Injection (WFI)

• EP Classifications:

  1. Purified Water (PW)

  2. Highly Purified Water (HPW)

  3. Water for Injection (WFI)

Subtypes of Water for Injection (WFI)

1. Sterile Water for Injection:

   • Used as a sterile diluent for parenteral products.

   • Packaged in single-dose containers (max 1L).

2. Bacteriostatic Sterile Water for Injection:

   • Contains antimicrobial preservatives.

   • For multi-dose products requiring repeated withdrawals.

3. Sterile Water for Inhalation:

   • Used in inhalators and inhalation solutions.

4. Sterile Water for Irrigation:

   • Packaged in larger containers (>1L).

Purified Water Treatment Process

• Purified water used in:

  • Oral liquid preparations (syrups, elixirs).

  • Oral solid preparations (tablets).

  • Topical preparations (creams).

Treatment Process Techniques

1. Ion-Exchange

   • Reduces water hardness using resin beds exchanging Na with Ca and Mg ions.

   • Regeneration occurs using brine solution.

2. Reverse Osmosis (RO)

   • Uses semi-permeable membranes; high pressure forces feed water through.

   • Rejects dissolved solids and microorganisms.

3. Deionization

   • Removes cations and anions using ionic exchange resin beds (H+ and OH- ions).

4. Ultrafiltration (UF)

   • Membrane filtration process using 0.02 micron membranes.

   • Removes particles larger than submicron size.

5. Distillation

   • Converts water to vapor and back to liquid, removing impurities.

   • Different types include simple, fractional, steam, and vacuum distillation.

Specification Requirements

• Compliance with USP standards in terms of:

  • Microbiological assay values.

  • Contaminants and conductivity levels.

  • Total organic carbon (TOC) levels.

Quality Control Testing Methods

1. Conductivity Testing:

   • Measures dissolved ions to reveal impurities.

2. Total Organic Carbon (TOC):

   • Assesses organic contamination levels.

3. Total Viable Counts (TVC):

   • Counts microorganisms by incubating water samples.

4. Endotoxin Testing:

   • Detects bacterial endotoxins using LAL test.

Storage and Distribution

• Systems designed to prevent contamination:

  • Closed systems to maintain water purity.

  • Regular cleaning and sanitization essential.