Not health advice. Contact your local water utility for concerns.
Data from EPA Water Quality Reports. For official information, contact your water utility or health department.
Analysis of chromium contamination levels across Idaho cities
Complete list of cities where chromium has been detected, sorted by level
| City | Level | EPA Limit | % of Limit | Status |
|---|---|---|---|---|
| LewistonGrade B- | 0.048 mg/L | 0.100 mg/L | 48.0% | Safe |
| AmmonGrade B- | 0.041 mg/L | 0.100 mg/L | 40.5% | Safe |
| EagleGrade C+ | 0.035 mg/L | 0.100 mg/L | 34.5% | Safe |
| BoiseGrade B+ | 0.030 mg/L | 0.100 mg/L | 29.7% | Safe |
| Garden CityGrade B- | 0.025 mg/L | 0.100 mg/L | 24.5% | Safe |
| MoscowGrade B+ | 0.021 mg/L | 0.100 mg/L | 20.7% | Safe |
| BlackfootGrade C+ | 0.016 mg/L | 0.100 mg/L | 16.2% | Safe |
| MeridianGrade C+ | 0.015 mg/L | 0.100 mg/L | 15.2% | Safe |
| PocatelloGrade A | 0.013 mg/L | 0.100 mg/L | 13.3% | Safe |
| NampaGrade B- | 0.011 mg/L | 0.100 mg/L | 11.4% | Safe |
| Twin FallsGrade B- | 0.011 mg/L | 0.100 mg/L | 10.9% | Safe |
| CaldwellGrade B+ | 0.0088 mg/L | 0.100 mg/L | 8.8% | Safe |
| KunaGrade B- | 0.0075 mg/L | 0.100 mg/L | 7.5% | Safe |
| JeromeGrade B | 0.0050 mg/L | 0.100 mg/L | 5.0% | Safe |
| ChubbuckGrade A- | 0.0049 mg/L | 0.100 mg/L | 4.9% | Safe |
| Post FallsGrade A- | 0.0048 mg/L | 0.100 mg/L | 4.8% | Safe |
| Mountain HomeGrade A- | 0.0027 mg/L | 0.100 mg/L | 2.7% | Safe |
Chromium-6 (hexavalent chromium) is a known human carcinogen when inhaled. When ingested through drinking water, chromium-6 has been shown to cause cancer in laboratory animals. Health effects include damage to the liver, kidney, and gastrointestinal and immune systems. California has proposed a specific MCL of 10 ppb for chromium-6, much lower than the federal total chromium standard.
Discharge from steel and pulp mills; erosion of natural deposits; industrial pollution
Based on our analysis of EPA Safe Drinking Water Information System (SDWIS) data and local water utility reports,chromium has been detected in 17 Idaho water systems. The average level across all tested cities is 18% of the EPA Maximum Contaminant Level (MCL), with the highest detection at 48.0% of the limit.
The EPA MCL for total chromium is 0.1 mg/L (100 ppb). The EPA MCL for chromium is 0.1 mg/L. This limit is set to protect public health based on available scientific evidence about the contaminant's health effects.
17 Idaho cities have chromium detected in their water supply. All tested cities are within EPA safety limits.
Potential carcinogen, liver and kidney damage, gastrointestinal effects. The most vulnerable groups include children and people with kidney disease.
The most effective methods for removing chromium include Reverse Osmosis, Strong Base Anion Exchange. Look for filters certified by NSF/ANSI for chromium reduction.
The EPA Maximum Contaminant Level (MCL) for chromium is 0.1 mg/L.The EPA MCL for total chromium is 0.1 mg/L (100 ppb).
Recommended filtration methods for chromium removal:
Removes both chromium-3 and chromium-6
Best for chromium-6
pH dependent