The pH value of lead in water can range from acidic to basic, but it is most soluble in nearly all natural water with a pH between 6 and 8. Lead is colorless, odorless, and tasteless in water, making it difficult to determine if your water contains lead without testing. The only sure way to determine if your water contains lead is to have the water tested by a state-accredited water testing lab.
Understanding the pH Range of Lead in Water
Lead is most soluble in water with a pH between 6 and 8, which is the typical range for most natural water sources. However, if the pH of the water is below 6.5, it has a greater capacity for the water to leach lead from plumbing components such as pipes, pipe joints (solder), or water fixtures (valves, faucets, etc.). This type of problem is associated primarily with private water systems using groundwater that has a pH below 6.5.
The second way that lead can become a problem is when some change in water chemistry occurs, either through mixing water sources or making adjustments in water chemistry to deal with drinking water issues other than lead. Over time, lead salts or lead oxides may have built up as films or in scales within distribution systems. A sudden change in water chemistry may cause lead to be released from scales back into treated water within the distribution.
Balancing the pH of Lead in Water
To balance the pH of lead in water, you can neutralize the acidic water for both corrosion control and lead reduction benefits. If you are on a public water system, the water utility is required by law to periodically check tap water from those areas most likely to have lead contamination. This especially applies to housing areas with lead service lines or copper plumbing with lead-based solder that has not been replaced.
Home Remedies to Remove Lead from Water
There are several home remedies to remove lead from water. One effective method is to use a reverse osmosis (RO) system, which can remove up to 99% of lead from water. Another method is to use a water filter that is certified to remove lead, such as a carbon block filter or a distiller.
Other Contaminants Associated with High pH Lead in Water
In addition to lead, there are other contaminants, chemicals, and substances present in water with a high pH of lead. These include arsenic, aluminum, and other metals that can accumulate in the corrosion scale of lead pipes. A significant fraction of the total lead concentration in water is traced to particulate lead, which is the primary contributor to total lead concentration in flowing systems.
Importance of Regular Water Testing and Appropriate Action
To deal with these contaminants, it is important to test your water regularly and take appropriate action based on the test results. This may include using a water filter, replacing lead pipes, or adjusting the pH of your water. It is also important to flush stagnant water from the lines before filling containers for drinking or cooking to eliminate most of the lead risk.
Conclusion
In summary, the pH of lead in water is an important factor to consider when it comes to water quality. By understanding the pH range of lead in water, how it can affect lead solubility, and how to balance the pH, you can take steps to ensure that your water is safe to drink. Regular testing, using home remedies such as water filters, and taking appropriate action based on test results can help you maintain safe levels of lead and other contaminants in your water.
References:
1. Assessing the Lead Solubility Potential of Untreated Groundwater in Pennsylvania, Journal of Environmental Quality, 2011.
2. Lead in Drinking Water – Penn State Extension, 2022.
3. Effect of pH on the concentrations of lead and trace contaminants in drinking water delivered through lead pipes, Journal of Hazardous Materials, 2011.
4. Water Health – If normal lead (Pb) concentrations in freshwater are much lower than the standards set for drinking water, how does lead concentration get high enough in drinking water to become a health issue? Freedrinkingwater.com, 2023.
5. Effect of pH on the concentrations of lead and trace contaminants in drinking water, Journal of Environmental Quality, 2011.
6. Lead, Pb (atomic no. 82) – EPOC, Environmental Protection Agency, 2017.