In September the BDJ shared the story of ecologist Li An Phoa, founder of Dutch foundation Drinkable Rivers, who was about to begin a 220-mile walk with partner Maarten van der Schaaf from the source of the Thames to its mouth, in support of their vision for a world with drinkable rivers.1 Li An's uncle, maxillofacial prosthodontist Khee Hian Phoa, was due to join the pair for a section of the walk to help raise awareness of clean water among the dental profession and clean water's role in sustainability.

Li An and Khee Hian have been in touch with the BDJ's News Editor with an update on their progress, a week into the four-week walk. Li Ann writes:

'After seven days of walking along the Thames (currently 136.5 km) and an events day in Oxford (Fig. 1) we have reached 128 people. People have joined the walk with us (Fig. 2), carried out citizen science measurements, hosted us or joined our events.

Fig. 1
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Li An (left), Maarten (centre) and Khee Hian in Oxford opposite the Vaults & Garden where the Saturday event was held

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Fig. 2
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A group of walkers between Oxford and Abingdon

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'There is a lot of frustration and anger about the situation with untreated sewage water entering our waterways. With our walk we wish to underline the connectedness among all people within a watershed, or catchment area. We also propose and invite people to adopt drinkable rivers as a compass, to give us direction to act that is both simple to understand, as well as positive and measurable.

'My uncle, dentist Khee Hian, arrived on Friday evening by train and participated in the evening event in Oxford with a group of 50 people and joined the walk between Oxford and Abingdon, a 23 km stretch. Tomorrow he will join our walk from Abingdon to Dorchester.'

In Oxford the group assessed and explored sustainable dental products, including plastic-free dental floss and toothpaste tablets (Fig. 3) which have plastic free packaging, are said not to contain nanoparticles of plastics, and can be used with almost no water.

Fig. 3
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In Oxford exploring sustainable dental products

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To find out more about Drinkable Rivers and the Thames walk - which was due to conclude on 17 October - and Li An and Maarten's book, visit https://drinkablerivers.org/.