May 23, 2024

Welsh company using British shells to reduce rising hot tub infections and cut plastic waste

A Welsh company that pioneered development of water cleaning products to protect people from swimming pool and hot tub infections – by innovatively using British shells – is now also preventing plastic from heading to landfill or the ocean.

Pennosan was well placed to respond to the boom in hot tub and pool sales at the start of the pandemic having created a range of natural water clarifiers to help keep people safe.

The company’s products are made using crab, langoustine and shrimp shells from around the UK including Scotland and Cornwall and Northern Ireland. All the shells were destined for landfill.

But when the hard outer skeletons of shellfish are specially treated, they produce chitosan, a type of sugar polymer which has a number of commercial and biomedical uses.

As well as being a natural product that is wholly biodegradable and 100% allergen free, chitosan is also antimicrobial. Chitosan cleans pool and hot tub water by clumping together floating dirt, oils and dissolved metal particles, which are too small or light to sink to the bottom to be filtered out.

Hot tub and swimming pool sales have boomed in the past 12 months thanks to COVID-19 and the rise of the ‘staycation’. But many people are unaware of how to keep them clean and safe for use.

Environmental Scientist Sue Dentley of Pennosan Limited, which is based near Pwllheli,said: “We were concerned that so many people are unaware of the health risks if they don’t look after their hot tub or swimming pool water properly.

“Problems can range from itchy skin, a bacterial skin infection ‘hot tub rash’ to, in extreme cases, respiratory problems.

“We recycle British seashells to create environmentally friendly, safe products high in antimicrobial properties which help to keep water clean and fresh. Our products also reduce chlorine doses, which is better for people’s skin and eyes.”

The company prides itself on its green credentials.

Sue said: “Sustainability has always been a driving force behind our business. As well as recycling seashells and putting them to a good use, we wanted to do what we can to help reduce the number of plastic bottles going into the recycling system.

“Our products are supplied in recyclable plastic bottles, made from HDPE, with removable labels. Although HDPE can be recycled up to 10 times, the plastic in each bottle has an expected service life of up to 20 years.

“Because chitosan is anti-microbial, the bottles don’t harbour germs and can be refilled hundreds of times.”

It is estimated that around 13 billion plastic bottles are used in the UK every year with only 7.5 billion being recycled.

Paul McMichael, Service Director of Bell Leisure Swimming Pools in West Sussex, asked Pennosan to help reduce the amount of single use plastics they were using in their pool maintenance operations.

Paul said: “We carry out over a thousand pool services a month across West Sussex.

“If each customer had one bottle every year, over 20 years that equates to 8,000 bottles. Now imagine that each customer had two bottles a year – that’s 16,000 bottles.

“By refilling in this environmentally friendly way, we can reduce the number of bottles going into the recycling system by up to 15,600 over a 20-year period. That’s a lot of bottles!

“Since the start of the pandemic there has been a boom in hot tub sales, but we have noticed a shocking lack of knowledge from the people who have bought them about how to actually look after their water quality.

“You’re meant to shower before getting into a hot tub, but many people jump straight in with sun cream, make-up and fake tan on which leaves a fatty scum line in the water.

“So many people have bought hot tubs thinking they are easy to maintain without understanding that you need to change the water every 4-6 weeks – not just once a year – and you need to spend time throughout the week to test and dose it accurately.

“You don’t add chemicals to a bath, but you drain it after a single use, don’t get back into the water and generally don’t share it.

“With a hot tub, you will be introducing bacteria as soon as you get into it. If you don’t have the chemicals balanced and the sanitiser at the correct level, those bacteria will multiply.

“It’s not surprising that there’s been an increase in GPs seeing hot tub users with itchy ‘hot tub’ skin rashes caused by germs in the water.

“Pennosan works for 100% of the pools I look after. It has a multitude of great benefits behind the scenes without influencing other products. It’s the key for good swimming pool chemistry.

“Not only does it help to keep water safe for bathers, it also gives a lovely ‘gin clear’ clarity to the water. The fact that it is made from crushed British seashells and uses recyclable containers is something that impresses customers too.”

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