Does a Brita filter remove chromium-6?

No. Standard Brita pitcher filters use activated carbon certified to NSF 42 for taste and odor. Activated carbon has limited effectiveness against chromium-6 at typical concentrations. For reliable chromium-6 removal, you need reverse osmosis or another system specifically tested and certified for chromium reduction. Check the NSF product database for any filter you're considering.

What NSF certification covers chromium-6 removal?

NSF/ANSI 58 is the standard for reverse osmosis systems. Systems certified under NSF 58 have been tested for a defined set of contaminants including chromium. When looking at a specific product, check the NSF certificate to confirm chromium is listed among the certified reductions for that model, not just that the system is "NSF 58 certified" broadly.

How much chromium-6 does reverse osmosis remove?

NSF 58-certified RO systems typically achieve 85-95% or greater reduction of total chromium in controlled testing. Real-world performance depends on membrane age, water pressure, and temperature. A membrane past its rated service life will show declining rejection rates for all contaminants including chromium.

Is a whole-house filter needed to remove chromium-6?

For most households, no. Chromium-6 health risk comes from ingestion. Treating drinking and cooking water at the point of use with an under-sink RO addresses the primary exposure pathway. Whole-house chromium-6 removal systems exist but are expensive and aren't necessary for the majority of households unless levels are very high or there's a specific skin exposure concern.

How do I know if my RO system is actually removing chromium-6?

Test your filtered water. A certified lab test for chromium on your filtered water output tells you your actual reduction rate. Do this after the system runs for 2-3 weeks to flush the new membrane. Repeat annually or whenever you replace the membrane.

How to Remove Chromium-6 from Drinking Water

Health disclaimer: This page provides general information about chromium-6 treatment options for drinking water. It is not medical advice. If you have health concerns related to chromium-6 exposure, consult your doctor. For treatment system selection, consult a licensed water treatment professional.

Chromium-6 removal comes down to one technology: reverse osmosis. Other common filter types don’t do the job.

That’s a short answer, but the details matter. Not every RO system is certified for chromium. And verifying the treatment is working requires a follow-up test, not just trust.

What NSF Testing Shows

NSF/ANSI 58 is the independent standard for reverse osmosis drinking water treatment systems. When a manufacturer submits an RO system for NSF 58 certification, the system is tested against a defined list of contaminants at specific challenge concentrations. Chromium is on that list.

The nuance is that NSF 58 certification covers the product line as a whole, but individual models within a line may have different certified reduction claims. A manufacturer can legitimately call a system “NSF 58 certified” if it meets the structural and materials requirements of the standard, even if that specific model wasn’t tested for every possible contaminant reduction.

Before buying any RO system for chromium-6, check the NSF product database at nsf.org/certified-products. Search the specific model number and look at what contaminants are listed as certified reductions. You want to see “chromium (hexavalent)” or “chromium (trivalent)” and “chromium (VI)” in the certified claims. If the certificate doesn’t show chromium reduction for that model, don’t assume it handles chromium-6 just because it’s NSF 58 certified.

Most major under-sink RO brands, including APEC, iSpring, Waterdrop, and AquaTru, have models with certified chromium reduction. Look up the specific model you’re considering, not the brand.

Step-by-Step: Choosing and Installing an RO System

Step 1: Confirm chromium-6 is present. Check your utility’s Consumer Confidence Report or use the best mail-in water tests to test your tap water before buying treatment equipment. If chromium-6 is below detectable levels in your water, you don’t need specialized treatment.

Step 2: Choose under-sink RO for most households. An under-sink RO system treats water at the kitchen faucet, covering drinking and cooking. That’s where ingestion exposure happens. Under-sink RO units run $150-400 for a quality system. That’s the right starting point for the vast majority of households.

Step 3: Check the NSF certification for your specific model. Use the NSF product database as described above. Confirm chromium is in the certified reduction claims for the model you’re buying, not just for the brand’s broader product line.

Step 4: Install and run the flush cycle. Follow the manufacturer’s installation guide. Most under-sink RO systems connect to your cold water supply line and drain. The installation process typically takes 30-60 minutes with basic plumbing skills. After installation, run the flush cycle as directed, which usually means filling and discarding the storage tank 2-3 times. New membranes release a small amount of manufacturing residue that the flush cycle removes.

Step 5: Test your filtered water after 2-3 weeks. Don’t assume the system is working. Collect a sample from the RO output faucet and send it to the same certified lab you used for your source water test. This confirms your actual reduction rate and gives you a baseline to compare against in future annual tests.

What Doesn’t Work

Activated carbon is the technology in most household filters, including pitcher filters, faucet-mounted units, and many under-sink systems that aren’t RO. Carbon works well for chlorine, taste, odor, and some organic compounds. It doesn’t reliably bind chromium-6 ions at the concentrations found in tap water.

Don’t count on a Brita, PUR faucet filter, or similar carbon-based product for chromium-6. They aren’t certified for it because they aren’t effective at it.

Water softeners also fail here. Softeners use ion exchange to swap calcium and magnesium for sodium, which addresses hardness. Chromium ions don’t get exchanged in that process. A softener will do nothing to your chromium-6 level.

Faucet-mounted carbon filters have the same problem as pitcher filters, different form factor, same chemistry limitations. Even expensive countertop carbon filters won’t address chromium-6 without an RO membrane in the system.

If a filter isn’t specifically NSF 58 certified with chromium in the reduction claims, assume it doesn’t remove chromium-6.

Maintaining Your System

A system that isn’t maintained won’t perform as certified. RO membranes have a service life, and chromium rejection rates decline as the membrane ages.

Pre-filters (sediment and carbon) typically need replacement every 6-12 months depending on your water quality. Clogged pre-filters reduce water pressure to the membrane, which directly affects rejection performance. Chromium removal efficiency drops when pressure drops. Change pre-filters on schedule.

RO membranes are rated for 2-5 years for most under-sink systems. Some higher-end systems claim longer lifespans. Follow the manufacturer’s recommendation and don’t stretch it to save money. The membrane is the component doing the heavy lifting for chromium removal.

A TDS meter gives you an ongoing rough indicator. Measure your filtered TDS when the system is new and note the rejection rate. If TDS starts climbing compared to your original baseline, the membrane may be losing efficiency. Annual chromium testing on your filtered water is the definitive check.

If your utility has shifted to a new water source, or if you’ve had any changes to your home plumbing, retest. Chromium levels in source water can change seasonally and with supply changes.

For product comparisons, see the best under-sink RO systems page.

For background on chromium-6 health effects, the federal regulatory gap, and where contamination is highest, see the chromium-6 contaminant overview.

Sources

NSF International, “NSF/ANSI 58, Reverse Osmosis Drinking Water Treatment Systems”: nsf.org
EWG, “Chromium-6 Is Widespread in US Tap Water”: ewg.org/research/chromium-6-widespread-in-us-tap-water
EPA, “National Primary Drinking Water Regulations, Chromium”: epa.gov/ground-water-and-drinking-water/national-primary-drinking-water-regulations
NSF, “Certified Product Listings”: nsf.org/certified-products

Health disclaimer: This page provides general information about chromium-6 treatment options. It is not medical advice. Always verify treatment effectiveness by testing your filtered water through a certified laboratory. For system selection at high contamination levels, consult a licensed water treatment professional.