2 minute read
Lead in Water
With all the safeguards and regulatory laws of the modern world, we tend to think of lead problems as isolated incidences, most famously the Flint, Michigan disaster that made headline news worldwide in 2014. And while it is true that Flint is nearly a worst-case scenario when identifying potential weak links in the US regulatory chain, there’s a strong argument that lead poses a much higher threat to public drinking water than most people realize. In the USA alone, over one million miles of lead pipe transporting “safe” water to public taps remain in use.
The reason why these dangerous pipes are not considered an emergency was the unplanned benefit of what is now known as “biofilm”. Biofilm is an accumulation of organic and inorganic, living and dead material collected on the interior pipe surface, which can effectively sequester lead particles that would otherwise contaminate the water. What happened in Flint was pure negligence: switching water sources, and therefore, water chemistry, disrupted the integrity of the biofilm lining, releasing incalculable amounts of lead directly into residential home drinking water. As of 2018, 7,600 lead pipelines in Flint have been replaced, leaving half a million pipelines to go. The city reassured its residents that in the remaining lead pipes, the biofilm had returned, so not to worry.
Lead pipe concerns are certainly not just an American phenomenon. Although banned in the UK for many years, homes built before 1970 used lead pipes for their water main. In Canada, the results of a multi-year long study across 11 cities found that 18% of water tests given produced results over the US limit of 15ppb. This shocking result is even more disturbing knowing that Canada has the third-largest per-capita freshwater reserve on the planet. It is estimated that old lead pipes service about half a million homes across the county.
There is a well-documented human cost to lead consumption, including heart disease, stroke and most tragically, low IQ in children. There is no level of exposure to lead that is known to be without harmful effects. One of the reasons growers use water filters for lead (and other heavy metals) is that these compounds can be transmitted from plant to human through consumption: some plants bio-accumulate metals, and when consumed, transfer concentrated amounts of the toxic substance. The easiest way to prevent waterborne lead from entering your body (or your garden) is to use a reverse osmosis filter to produce water for washing and consumption.
By Richard Gellert
Richard is an adventure-seeker; he loves wilderness, biking, and hitting the slopes - the steeper, the better. Also an avid gardener, Rich has created extensive gardens to grow fruits and vegetables for his family year-round. He is the president of Hydrologic Purification Systems, a company delivering top-shelf hydroponic water filtration systems to consumers. Speaking five languages, and with as many advanced degrees, Rich has become the industry’s leading expert in water quality, facility discharge, reclamation systems, and regulation compliance. His articles have appeared in MaxYield, HydroLife, Garden Culture, and Urban Garden.
