It’s World Plumbing Day on 11 March and our message couldn’t be clearer: let’s get lead out of the water supply.
The World Health Organisation (WHO) publish Water Quality Guidelines stating that infants and children are considered to be the most sensitive subgroups of the population and are most at risk from Lead in drinking water. The WHO suggests that the presence of Lead in tap water is primarily due to the corrosive water effects on domestic plumbing systems containing lead pipes, solder or fittings with high lead content – or from the service connections to homes.
Several factors are judged to affect the rate at which lead is dissolved from the plumbing system – these include pH (soft, acidic water being most plumbosolvent), temperature, alkalinity, scale in pipe and standing time of the water (stagnation). The WHO points out that significant changes in the water quality of a supply, resulting from, for example, changes in treatment or changes of source, can result in changes in plumbosolvency or solubilisation of lead deposits, or both. However, in situations where water treatment fails, domestic plumbing can make the drinking water into a toxic soup which presents a significant danger to human health.
In April 2014, the people of Flint, Michigan, USA, were exposed to Lead toxins in the tap water; in a bid save money, Flint authorities drew some river water which was ‘untreated’ rather than the treated source they normally purchased. In Clark’s (2018: 214) book “Flint’s water and the American urban tragedy”, she refers to the place as “The Poisoned City”, chronicling the town and its people:
“We built our cities out of lead. We were sure we could make this metal work for us. History revealed a pattern of poisoning, but we were certain that we could contain it, control it. Progress came when we acknowledged how terribly harmful lead is and instituted anti-lead laws that reduced our exposure to one of the world’s best-known neurotoxins. But the next great challenge – a tremendously difficult one – is reckoning with the lead that still in our environment.
The Flint tragedy is a reminder that many domestic plumbing systems in the UK and the Western World have to potential to threaten human health and that the well-being of the population relies heavily on phosphate water treatment.
Compared to other chemical hazards, Lead is exceptional because most lead in drinking‐water arises from lead service connections and plumbing in buildings, and the remedy consists principally of removing service connections, plumbing and fittings containing lead. However, during my three decades working as a hands-on plumber in the UK, I always used lead-free solder for all installations but we removed very few existing copper plumbing systems containing lead joints because they were often very robust and it was legal with the Water Regulations Advisory Scheme (WRAS) to join new lead-free plumbing onto old toxic systems.
There is now growing evidence that plumbing companies in the UK are largely ignorant to the ‘significant’ dangers of Lead which are not communicated sufficiently to the public and plumbers by water authorities and environmental agencies. Reddy’s (2017) World Plumbing Council report stated that the UK organisation Watersafe limited their warnings only to the dangers of ‘lead pipes’ in domestic dwellings, hardly mentioning the significant and much more widespread dangers from copper systems containing lead joints.
Such is the level of incompetence regarding the dangers of Lead in the UK, that a major provider of plumbing qualifications – the British Plumbing Employers Council (Bpec) – were arguably promoting the use of lead solder for training in UK Further Education colleges without providing the necessary health and safety warnings at point of use (leadinthewater, 2018). This type of hazardous information in training, along with incompetence on a National level in Further Education Colleges’ systems of education and training, has had an impact on the best practices of the UK plumbing and heating community. In 2019, lead-solder is still used extensively by Registered Gas Installers for non-potable work like copper-pipe central heating systems. If you visit Twitter, there have been many revelations (via many high definition images) of installations that are highly suspected of containing lead solder on drinking water supplies. The registered gas engineer who did the installation below in October 2018 said it was the 42nd boiler installation that year.
It is important to point out that new lead-solder used on a drinking water installation has a much higher dissolve rate in early life (the rate of lead dissolved in the water tails off over time). Therefore, these new installations are a particular worry.
In UK Further Education, I recently worked as a plumbing teacher over a three year period using ‘Facebook Closed Group’ communities of practice project with plumbing apprentices. Nearly all apprentices in my group at one college were observed to be using lead solder at work on central heating systems between 2015-2018. It was also noted from the Facebook community images presented by students that some plumbing apprentices made mistakes and mixed up the lead-solder and unleaded solder on new houses. The use of lead solder can be easily identified on images of plumbing because it has a different colour to lead-free (lead solder is dull grey and lead-free shiny and silver). The lead solder also has a different plastic range to lead-free solder when the materials are melted. This means that lead solder will make blobs and lead-free will not (lead-free solder is either liquid or solid with little in between compared to lead solder which remains an plastic state when melted for several seconds).
In order to communicate the significance of the dangers of Lead, the World Health Organisation have included the toxic substance in the ‘Ten chemicals of major public health concern’ and it sits alongside other dangerous chemicals that you should never not expose people to – including arsenic, asbestos and mercury.
The WHO state clearly that for “new installations or repairs, lead‐free service connections and solder and low lead alloy fittings should be used to prevent the introduction of contamination”.
It may be an expensive undertaking to re-plumb a house and it is recognised by the WHO that not all water will meet the guidance value immediately but they recommend that all other practical measures should be taken to reduce total exposure to lead, including corrosion control.
Changes to the ‘Drinking Water EU Directive’ meant fitters and plumbers across Europe have been obligated since December 2013 to use materials that comply with these guidelines. This means that “all those responsible in the action chain” – not only the fitters – can expect legal consequences if unapproved materials are used in construction projects for drinking water installations after 10th April 2017 (Beulco, 2019). For the UK, this includes the installation of heating systems with lead-based solder which are intended to be connected to the drinking water mains.
In summary there is no place for the use of lead solder in domestic plumbing and heating in 2019 and those continuing with its use are risking the health and well-being of their clients.
References and Further Reading:
WHO (2016) Water Quality Guildines 12: Fact Sheet