The Difference Between Trivalent and Hexavalent Chromium: Why Total Chromium Data Isn’t Enough
Chromium appears mainly in two forms in water: trivalent chromium (Cr(III)) and hexavalent chromium (Cr(VI)), also called chromium-6. While total chromium measurements report the sum of both, they do not specify the proportion of chromium-6, which is the form drawing the most attention. In the Parish Water Company system serving your area in Louisiana, government sampling from 2013 to 2015 found no detections above reporting limits for total chromium, but did detect chromium-6 in 1 out of 48 tests. This detection measured 0.039 micrograms per liter (µg/L, or parts per billion), just above the reporting level of 0.03 µg/L. Total chromium’s federal maximum contaminant level (MCL) is 100 µg/L, far higher than these measurements, and there is no federal MCL for chromium-6. Because total chromium data includes all chromium species, it cannot alone establish chromium-6 levels in your home water.
How the Fleck System Addresses Chromium(VI) in Residential Water
The Fleck Chromium-6 Filter is designed to specifically target hexavalent chromium molecules in household water supplies. Using filtration media and a configuration optimized for chromium-6, this system reduces the concentration of chromium(VI) to lower levels, helping to improve water quality related to this contaminant. The Fleck System ships ready to configure for use in residential settings, allowing direct purchase and setup to suit household water treatment needs involving chromium-6.
Information to Gather Before Seeking Treatment Advice
Before pursuing a water treatment solution, recording accurate test results from your own water is essential. Area-level data indicates background levels but does not reflect your well or tap specifically. Testing for chromium-6 at a certified laboratory will provide the concentration of hexavalent chromium in your home water. Additionally, obtaining total chromium levels can assist in confirming overall chromium presence. Knowing your water source type and any historical treatment is also helpful when considering options like the Fleck Chromium-6 Filter.
Potential Effects of Untreated Chromium-6 Over Time
Long-term exposure to chromium-6 in drinking water at elevated concentrations can raise concerns related to water aesthetics and health considerations, although federal MCLs currently apply only to total chromium. Chromium-6 can contribute to taste and staining issues depending on concentration and water chemistry. Without treatment, household fixtures and water-using appliances may experience discoloration or deposits influenced by chromium species, and residents may wish to reduce chromium-6 levels as a precautionary measure.
Fixtures and Appliances Most Impacted by Chromium-6 Levels
Water fixtures such as faucets, showerheads, and water heaters can accumulate deposits related to chromium compounds over time. Appliances relying on water quality, including dishwashers and ice makers, may also be affected by elevated hexavalent chromium concentrations, influencing both performance and cleanliness. Treating chromium-6 in the water supply can help maintain appliance longevity and water appearance.
What This Area Data Does Not Mean for Your Household
While government sampling of the Parish Water Company system shows only one chromium-6 detection slightly above the reporting level and no exceedances of federal limits for total chromium, this does not establish the chromium-6 concentration in your home water. Detection is not synonymous with a violation or unsafe condition. You should not assume your water matches the reported system averages. Individual testing is the only way to confirm chromium-6 levels specific to your household, which will inform whether treatment with the Fleck Chromium-6 Filter or other options is appropriate.
Where this information comes from
Source: EPA SDWIS public water system record. Sampled 2013-11-09. These figures describe the public water system's record, not the plumbing inside any individual building.
On record: EPA UCMR3 monitoring (2013-2015) for Parish Water Company (LA1033019), LA: 96 results across 2 listed contaminants, 1 detections above the reporting level; no federal MCL for hexavalent chromium; total chromium MCL 100 ug/L