Lead (Pb)
Heavy Metal · measured in mg/L
A toxic heavy metal that leaches into water mainly from aging plumbing rather than the water source itself.
Common sources
Corroded lead pipes, lead solder on copper pipe joints, and brass fixtures — especially in homes built before 1986. Also found near some industrial and mining sites.
Health risks
Lead is a potent neurotoxin. In children, even low-level exposure is associated with reduced IQ, attention and behavioral problems, and slowed development; there is no known safe blood-lead level. In adults, chronic exposure is linked to elevated blood pressure, cardiovascular disease, and kidney damage. Pregnant women are a particular concern because lead crosses the placenta.
Sources & further reading
- EPA — Basic Information about Lead in Drinking Water
- CDC — Lead in Drinking Water
- Lanphear BP et al. (2005), 'Low-level environmental lead exposure and children's intellectual function', Environmental Health Perspectives, 113(7):894-899
- Bellinger DC (2008), 'Very low lead exposures and children's neurodevelopment', Current Opinion in Pediatrics, 20(2):172-177
How ClearDive rates severity
Readings are bucketed for map color-coding using thresholds referenced from EPA regulatory limits where available. This is a simplified public-awareness scale, not a substitute for certified lab analysis.
How to test for it
Field colorimetric test kits give a rough screen; for anything above trace levels, send a sample to a certified lab for ICP-MS analysis — this is the EPA-recommended method for compliance-grade results.