Do Not Give the Water to Infants: What a Nitrate or Nitrite Warning Means

What the notice actually said

Slater, Iowa, sits about twenty miles north of Des Moines. A sample of the city supply came back at 1.1 milligrams per liter of nitrite, just over the federal limit of 1 milligram per liter measured as nitrogen.123

The city told residents not to give the tap water to infants under six months or use it for formula, to mix formula with bottled water, and to talk to a doctor if pregnant. Adults and older children were told the water was fine. Then came the instruction that catches people off guard: do not boil it, because heating the water makes the nitrite stronger.12

Why boiling makes this one worse

Boiling is the reflex because most water notices are about germs. A boil water advisory works because heat kills bacteria and parasites. Nitrate and nitrite are not organisms. They are dissolved chemicals that do not break down at a rolling boil. Boiling turns water into steam and leaves the same chemical behind in a smaller volume. The Minnesota Department of Health states it flatly: boiling makes nitrate more concentrated.4 Penn State Extension says the same.6

Same logic as our guide to what boiling does and does not remove. Letting the water sit out does not help either.

Nitrate and nitrite are usually two different stories

Same family, same warning language, different routes in. Nitrate usually points upstream, at the source. EPA lists the sources for both as runoff from fertilizer use, leaking septic tanks and sewage, and erosion of natural deposits.3 Iowa monitoring has historically shown nitrate peaking in spring and early summer with heavy rain, then falling to near zero into early winter. A wet autumn breaks that: fall rains keep drainage tiles flowing and fall fertilizer adds to it.9 Iowa logged 36 nitrate violations at 13 water systems in 2025, up from 14 the year before.8

Nitrite more often points at the pipes. EPA describes nitrification as a microbial process in which ammonia is oxidized to nitrite and then nitrate, appearing in reservoirs or low flow sections where water sits longest. Systems that disinfect with chloramine add ammonia deliberately, giving those bacteria something to work on.10 That is worth a phone call: a source water nitrate problem is usually seasonal and regional, while a distribution nitrite problem can be confined to a few streets and is often cleared by flushing.

Who the warning is for, and who it is not

Six months is the line, and the reason is specific. Nitrate converts in the body to nitrite, which interferes with the way blood carries oxygen. The result is methemoglobinemia, long known as blue baby syndrome. Bottle fed babies under six months are at highest risk: infant digestive chemistry, a small body, and formula mixed with a lot of that water.4

Beyond infants the answer is less settled, and it is worth saying so rather than rounding it up into alarm. Penn State Extension points to World Health Organization and National Academy of Sciences reviews indicating nitrate does not represent a significant risk to adults at typical levels.6 Pregnancy is where the research keeps pointing somewhere. A Stanford analysis of 1.4 million California births, published in Environmental Health Perspectives in 2021, found nitrate between 5 and 10 mg/L associated with 47 percent higher odds of early preterm birth than water under 5 mg/L. Lead author Allison Sherris noted the association appeared even below the federal limit.7 Oregon State Extension lists low birth weight and preterm birth among pregnancy concerns.5 That is an association in one population, not a diagnosis, and a fair reason to raise with a doctor. If mixing formula, our guide to filtered water and baby formula covers the rest.

Where a filter fits, and where it does not

We sell carbon filters, so let us be direct. A carbon pitcher filter is not a nitrate filter, and Epic does not claim that it is.

Oregon State Extension puts it about as plainly as a public agency can: do not rely on activated carbon filters such as those found in a water pitcher or on your refrigerator, because these do not remove nitrate. Neither do water softeners.5 The methods that do are reverse osmosis, anion exchange, and distillation.56

If you are on a private well, or your utility has flagged nitrate, the honest path is a certified lab test plus one of those three technologies or an alternate supply. Our guides to testing a private well and testing your tap water cover getting a real number.

EPA on well water contaminants ↗

For area level background, Epic’s What’s in Your Water lookup is a starting point, not a test of your own tap.

What a carbon block is built for is a different list. The Pure XP and Nano XP cartridges hold NSF certification under NSF/ANSI Standard 42 for material safety and NSF/ANSI/CAN 372 for lead content: the filter is safe to drink through and will not add lead. Reduction performance is documented separately, in independent testing: lead at 99.9 percent under the NSF/ANSI 53 protocol, PFOA and PFOS under the P473 protocol, and over 99.9 percent of microplastics. Those are test results, not certified reduction claims, and none is a nitrate claim.11

If a pitcher fits the rest of what is in your water, explore Epic’s pitchers, dispensers, and bundles, and read the documentation for the exact filter.