The term 'heavy metals' covers a range of metallic elements that are toxic to humans at relatively low concentrations. In the context of drinking water, the metals of greatest concern include lead, arsenic, cadmium, chromium, mercury, nickel, barium, and selenium, among others. Lead and arsenic are covered in separate guides due to their specific significance in our service area. This guide focuses on the broader heavy metals picture and the industrial context most relevant to Metro East residents.

Heavy metals are persistent — they don't break down in the environment. Once they enter soil or groundwater, they tend to stay there. This is what makes industrial legacy contamination such a long-term concern even at sites where active operations ceased decades ago.

The Chemetco Inc. facility in Hartford, Madison County, is among the most significant industrial contamination sites in the Metro East. Chemetco operated a copper smelting and recycling facility at this location, and during its years of operation, the site became one of the most notorious illegal polluters in Illinois history. The company was convicted of Clean Water Act violations for illegally discharging copper-laden wastewater through a hidden underground pipe into a tributary of the Mississippi River.

The Chemetco site was added to the EPA's Superfund National Priorities List and has undergone remediation, but groundwater contamination from this and surrounding industrial sites in the Hartford corridor represents an elevated risk for heavy metals and industrial organic contaminants in the area. Customers in Hartford, Madison, Venice, and surrounding communities have legitimate reason to include a comprehensive metals panel in their water testing.

Heavy metals are toxic through several mechanisms, but a common thread is bioaccumulation — they accumulate in tissue over time and are difficult for the body to eliminate. The kidneys bear the primary burden of filtering metals from the blood, which is why kidney damage is a common effect of chronic heavy metal exposure across multiple compounds.

Cadmium is classified as a known human carcinogen and accumulates primarily in the kidneys. Chromium VI (hexavalent chromium) is a known carcinogen through inhalation and a probable carcinogen through ingestion. Mercury affects the central nervous system, with particularly serious effects on developing neurological systems in fetuses and young children. Barium affects the cardiovascular system. Nickel is associated with increased cancer risk and dermatological effects. The EPA has established MCLs for most regulated heavy metals, though health researchers sometimes consider these standards to underrepresent the actual risk at the lower end.

All three of our testing packages include a comprehensive metals panel using EPA Methods 200.7 and 200.8, covering 25+ individual metals including all of the compounds discussed above. If you're in or near the Hartford, Madison, Venice, or Granite City area, or in any neighborhood with significant industrial history, a metals test is a reasonable baseline investment regardless of your primary concern.

Treatment for heavy metals depends on the specific compounds present and their concentrations. Reverse osmosis is broadly effective across most heavy metals and is the most practical whole-spectrum treatment at the point of use. Ion exchange and adsorption media systems can be targeted to specific metals when a more focused approach is appropriate. As with all treatment decisions, the test results drive the system design — a broad metals screen tells us what we're actually dealing with before any equipment recommendation is made.