Oxidising biocide offers users ‘safer and easier’ route

Maintaining consistently clean water supplies is of importance in many industries, but is especially crucial within medical settings, where already vulnerable patients are at risk of contracting Legionnaire’s Disease — if Legionella bacteria levels are not tightly controlled — among other waterborne diseases. Bacteria grow in adherent biofilm colonies, making removal even more difficult.

Chlorine Dioxide is widely regarded to be the most effective water treatment chemical at penetrating and removing biofilm, killing bacteria, and preventing regrowth, but as it is traditionally applied in a gaseous form, there are challenges associated with its implementation. Chlorine Dioxide in gas form is highly volatile, cannot be stored, is explosive above 10% in the atmosphere, and is ignited by almost any form of energy. It requires on-site mixing, gasses off at elevated temperatures or turbulent systems, and, once mixed, has a short shelf life. These factors make it hazardous, time-consuming, and costly to use.

‘Lack of innovation’ in treatment chemicals

Chlorine Dioxide was discovered in 1811, and first commercially produced in 1940. It was initially used as a bleaching agent for textiles, wood, pulp, and paper, before transforming the way that drinking water is disinfected. Since then, there has been a lack of innovation in water treatment chemicals. In 2020 the founders of Synthesis discovered a unique oxidising biocide formulation, which had been created by a leading research scientist, but had not been commercially leveraged. Upon securing the commercial licence to distribute the chemistry to new markets, the Synthesis team has undertaken extensive testing, regulatory compliance, and commercialisation, with the aim of transforming global water treatment applications.

Klarolaks differentiates itself from current alternative chemicals by offering Chlorine Dioxide in a safer, more stable, and easier-to-use liquid format, thus providing the most versatile oxidant in water treatment. Klarolaks oxidises cell membranes of microorganisms, rupturing the cell wall, and effectively killing bacteria.

The broad spectrum of coverage, using several modes of action, negates the need for alternative biocide programmes and additional chemical use, while also preventing resistant strains developing. It is also worth noting that Klarolaks can be used for shock dosing, as well as low-level online constant dosing.

High levels of Legionella within a water system following sampling would suggest that the routine measures already deployed to prevent the bacterial growth are no longer effective. As Legionella bacteria can spread quickly under the right conditions, particularly when water temperatures range from 20-45 °C, a system disinfection may be required. If the bacterial issues are not rectified following a shock dose, constant online low-level dosing may be required as a long-term preventative solution.

Klarolaks was tested by Melbec Microbiology to validate compliance with BS EN 13623 for Legionella control. At 3 ppm of active Chlorine Dioxide concentration, Klarolaks met the log reduction requirement with a contact time of 60 minutes for Legionella pneumophila in buffered ferrous hard water. For Pseudomonas aeruginosa, Klarolaks met the log reduction requirement at a product concentration of 5 ppm when diluted in synthetic hard water.

The chemistry of Klarolaks delivers chlorine dioxide via an equilibrium reaction, recycling chlorite back into Chlorine Dioxide. The whole reaction is contained within the complex, therefore minimising any potential for the formation of gaseous chlorinated by-products, while the reprocessing nature of the reaction means less product is needed overall.

Whereas sodium hypochlorite and generated Chlorine Dioxide gas off at around 40 °C, and are therefore ineffective above this temperature, Klarolaks will operate effectively in temperatures up to 70 °C. Combined with the fact that Klarolaks remains active in turbulent environments, and can be applied directly into a tank without losing any chlorine dioxide through gassing off, it proves a step change in hospital and clinical settings, where water often sits at temperatures above 50 °C, and can be delivered in spray applications.

Key benefits of Klarolaks

Among the key benefits of Klarolaks are:

Klarolaks is highly stable, releasing minimal vapour across a wide temperature and pH range, and is safer and easier to transport and store, and suitable for a wide range of applications.
It can be dosed directly into a water supply using a single dosing pump and flowmeter, negating the need for costly generating units, storage, and mixing of hazardous precursor chemicals.
Compared with traditional water treatment chemicals, Klarolaks is less corrosive to water systems, reducing the need for maintenance and system downtime.
The cyclical nature of the equilibrium reaction allows for lower dosing. The drastic reduction in chemical usage reduces expenditure, due to the need for fewer deliveries and reduced storage capacity, and less wastage in use.
Reduced man-hours and labour costs, with the dosing process ‘much less intensive’ than traditional methods.
Simpler inventory planning and control due to longer shelf life, and generates lower wastage levels.
Using Klarolaks helps companies adhere to their ESG (environmental, social, and governance) targets, as the smaller doses and lower frequency of deliveries help minimise carbon footprint.
There are no complexed oxidants, minimising the formation of hazardous by-products or environmental pollutants, and further enhancing the ESG benefits.
Healthcare providers’ reputations are safeguarded by preventing system and site shutdowns due to contamination by waterborne pathogens.
The odour and taste of treated water remains unchanged.

Case study — Legionella outbreak in an NHS respiratory centre

The problem: To fully understand the positive implications of transitioning to this unique new chemistry, let us look at a scenario involving continued elevated counts of Legionella in an NHS respiratory centre. This particular respiratory centre relies on the adjacent hospital for its 
direct water supply, and experienced consistent Legionella contamination over the course of a year, with 14 out of 18 samples detecting Legionella, with 
counts ranging from 25 cfu / litre to 
900 cfu / litre.

Before Klarolaks was introduced, no previous treatment had been applied to address the issue. In an attempt to mitigate the problem, staff members had increased the water temperature and flushed the system, but this activity proved ineffective. The presence of Legionella continued to pose a significant threat to the well-being of patients whose respiratory systems were already compromised.

The solution: To address the Legionella contamination, Klarolaks was constantly dosed directly into the hot and cold water systems at 0.5 ppm using a temporary dosing unit. This solution was employed over a period of three months, with regular testing conducted using a photometer to measure Chlorine Dioxide levels.

The results: Monthly sampling was carried out throughout the three-month implementation period, to monitor the levels of Legionella. After just a month, a noticeable reduction in Legionella counts and overall bacterial levels was observed. This trend continued, and by the end of the three-month trial period, no Legionella was detected. While pre-test sampling resulted in 14 detections of Legionella, eight weeks into the study, only five detections remained, all at lower levels than before Klarolaks was introduced, and four weeks thereafter only one detection remained. The final sample had completely clear results, with no detectable Legionella seen. The implementation of Klarolaks effectively rectified the contamination issue throughout the respiratory centre, and reinstated certified safety parameters on all the wards, allowing for all activities to safely resume.

The utilisation of water treatment chemicals in hospital and clinical environments presents challenges, particularly concerning safety and efficacy. Traditional methods, such as Chlorine Dioxide in its gaseous form, pose significant risk and logistical complexities. Furthermore, there are elevated cost and labour demands to consider. Klarolaks offers a revolutionary solution by providing Chlorine Dioxide in a liquid format, ensuring safer handling, more stability, ease of application, and lowered costs. Its unique chemistry not only eliminates bacteria and prevents regrowth, but also reduces both the need for additional biocide dosing, and the risk of negative environmental impact.

Klarolaks contains active substances either already approved or still under review as part of the GB Review Programme for the purposes of Article 89 of the United Kingdom Biocidal Product Regulations (‘BPR’). Klarolaks may therefore be sold and used for product applications falling under PT5 (drinking water) and PT11 (cooling systems), and is compliant with the requirements of Articles 89 and 95 of the BPR.