Dreaded Pseudomonas – The Ozone Solution
Over the last decade, Pseudomonas aeruginosa has become one of the most common pathogens in source waters across India. While chlorine has been traditionally used to eliminate Pseudomonas from source water, it has been found that the dose and contact time required for chlorine to be effective has increased over the years, leading to inconsistent results. UV treatment also has failed to consistently remove pseudomonas. This has resulted in Ozone being the disinfectant of choice when it comes to Pseudomonas aeruginosa.
Pseudomonas
What is Pseudomonas?
Pseudomonas is a Gram-Negative bacteria, dreaded by both pharmaceutical companies and hospitals. Gram-negative bacillus of late presents a major clinical significance; many instances of infections with these organisms have been noted regularly now. Infections include bacteraemia/septicaemia caused by contaminated solutions. Environmental studies have revealed that the organism can survive in chlorine-treated municipal water supplies, making Pseudomonas removal challenging. The bacteria often colonize sink basins and taps, intubation tubes, humidifiers, incubators for new-borns, ice chests and syringes, contaminated medical devices such as blood gas analysers, nebuliser equipment and has become a potential reservoir for infections in the hospital environment. However, ozone has emerged as a powerful solution to remove Pseudomonas from water systems, providing more reliable protection compared to traditional methods.
Role of Bio films:
The sources of water in most Pharmaceutical Industry /hospitals are from sources outside and unknown to them. Water supplies are under contract to these water suppliers. This water is treated and used for all purposes including advanced treatment processes for Pharmaceutical compounding, Water for Injections in Pharmaceutical companies, and for all purposes in Hospitals. Pseudomonas can pass through even advanced treatment process and emerge in the final product water. As these ordinary treatment processes continue, there is a formation of biofilm in all the water pipes. Conventional Bio films removal with ozone methods process such as CIP with Hydrogen peroxide, per-acetic acid or even steam have not found to be too effective against Bio film removal .These biofilms provide safe haven to most of these opportunistic bacteria and they proliferate when opportunity arises. The locations that has been identified are areas, especially where there are increased storage facilities, and in areas where chlorine residuals are removed with SMBS. Effective methods to remove Pseudomonas from water systems and manage Pseudomonas in water pipes are crucial for maintaining a pathogen-free environment.
Inferences that can be drawn are:
All of them are Gram Negative.
All of them find their way into water through soil contamination/sewage contamination.
Most of them hide behind bio fouling material to escape disinfectant action.
All pseudomonas and many of the other species are chlorine resistant.
Likely ozone actions on these bacteria: Construction of Bacteria
Bacteria are microscopically small single-cell creatures that take up foodstuffs and release metabolic products and multiply by division. The bacteria body is sealed by a relatively solid cell membrane. Their vital processes are controlled by a complex enzymatic system.
Action of Ozone on Bacteria
Ozone interferes with the metabolism of bacterial cells, most likely through inhibiting and blocking the operation of the enzymatic control system. A sufficient amount of ozone breaks through the cell membrane, and this leads to the destruction of the bacteria.
Why Gram Negative Bacteria (Pseudomonas) are more susceptible to ozone?
Gram negative bacteria like Pseudomonas are more susceptible to ozone than gram positive organisms. Gram negative organisms, fatty acid alkyl chains, and helical lipoproteins are present. In acid-fast bacteria, such as Mycobacterium tuberculosis, one-third to one-half of the capsule is formed of complex lipids and glycolipids. The high lipid content of the cell walls of these bacteria may explain their sensitivity, and eventual demise, subsequent to ozone exposure. Ozone may also penetrate the cellular envelope, directly affecting cytoplasmic integrity, disrupting any one of numerous levels of its metabolic complexities.
Ozone skid to eliminate Pseudomonas in pharmaceutical water
Ozone solutions to obtain pathogen free water
Ozone is very effective for Pseudomonas removal because of its mode of action. Ozone is very effective against all pseudomonas strains, unlike chlorine. Ozone destroys bio-fouling material on the inner surfaces of the pipes and tanks, hence preventing subsequent proliferation of these bacteria and exposes them to ozone action.
Ozone on Bio films:
Biofilms can be classified as
- Primary films
- Secondary films
Primary films are the biofilms that have been formed and exist in layers on the surfaces of the tanks and pipes. Secondary films are Bio films that are relatively new and appear in clusters on the surfaces or in the pipes. Ozone can remove exo-polysaccharides in the biofilm matrices and is very effective against biofilms against secondary bio films and can remove them totally with small amounts of residual ozone and lower contact time. Residual ozone of below 0.3 ppm ozone has been found to be effective. Regular use of ozonated water will prevent the formation of such Bio films.
Conclusion
To summarize, Ozone is the best available technology to fight the dreaded Pseudomonas bacteria. Since no Pseudomonas strain has exhibited any resistance to Ozone treatment, the Ozone dosage and contact time to eliminate Pseudomonas is fixed and measurable. This results in easy online validation and process control unlike other disinfectants available. For pre-treatment systems, Ozone is generated using Ozone generators with air or Oxygen as a feed gas through the principle of corona discharge. For purified water systems, Ozone is also generated directly from pure water [water-based or electrolytic ozone generators. The Ozone generated is then mixed in the process water using diffusers or venturis to achieve the necessary disinfection goals.