Sources of Contamination

Sources of Contamination

Sources of Contamination

1 of 8

Sources - Water

  • Reduction in microbial count from water samples
    • Chemical treatment
      • Chlorine - Cl
      • Chlorination
      • Sodium hypochlorite - NaCl
      • 0.5-5ppm of free chlorine for most purposes
      • 50-100ppm of free chlorine for storage and distribution
    • Membrane filtration
    • UV irradiation
      • Short wavelength (250nm)
    • Heating
2 of 8

Sources - Operators

  • Contamination from skin (e.g. S aureus)
    • transient and resident microorganisms
    • can be associated with poor hygiene
  • Contamination from respiratory tract
    • coughs and sneezes
  • Reducing contamination from operators
    • Gloves
    • Face masks
    • Shoe covers
    • Hair nets
3 of 8

Sources - Surfaces

  • Building
    • Walls and ceiling
      • moulds a common flora (poorly ventilated buildings and painted walls)
      • use of disinfectants, laminated plastic, ventilation (filtration)
    • Floors and drains
      • easily cleaned
      • drains avoided in areas where sensitive products are being manufactured
    • Doors, windoes and fittings
      • prevention of dust
      • permit only light entry
4 of 8

Sources - Surfaces

  • Packaging
    • Contain the product (e.g. solution, dressing)
    • Prevent the entry of microorganisms (e.g. rubber cap)
    • Prevent the degradation of the product during storage (e.g. light, moisture)
    • Withstand the appropriate sterilisation process
      • heat sterilisation
      • gas sterilisation
5 of 8

Sources - Surfaces

  • Equipment
    • Variety of equipment
      • pharmaceutical manufacture
      • surgical equipment
      • critical, semi-critical, non-critical items
    • Reduction in microbial count
      • sterilisation (physical and chemical)
      • disinfection
      • single use items
6 of 8

Sources - Raw Materials

  • Products of natural origin
    • animal: gelatine, desiccated thyroid, growth hormones
    • plant: starches, gum acacia
    • British Pharmacopoeia: strict controls of E.coli, Salmonella spp. in particular
  • Reduction in microbial count from water samples
    • minimum water activity: spoilage
    • packaging (paper)
    • liquid and semi-solid raw materials (sometimes kept at higher temperature, but extra cost to company)
7 of 8

Sources - Atmosphere

  • Filtration
    • High-efficiency particulate air (HEPA) filters can remove up to 99.997% of particles greater than 0.3um in diameter
    • Complete room, confined to specific area (laminar air flow cabinet, isolators)
    • High-pressure rooms (positive pressure): keeps atmospheric contamination out
  • Chemical disinfection
  • UV irradiation
8 of 8

Comments

No comments have yet been made

Similar Pharmacy resources:

See all Pharmacy resources »See all PH1123 resources »