Lead in Drinking Water: What Every Parent Must Know

In April 2014, the city of Flint, Michigan switched its water source to save money. Within weeks, residents were calling to complain about discoloured, foul-smelling water. Within months, a paediatrician named Mona Hanna-Attisha began noticing something in her clinic data: the proportion of children with elevated blood lead levels had nearly doubled in some Flint zip codes.

The state initially pushed back on her findings. It took almost a year for the federal emergency declaration that followed.

By then, thousands of children had been drinking lead-contaminated water for over a year. At levels that measurably damaged their developing brains. The exposure was invisible — lead in drinking water has no taste, no colour, no smell. And it came not from the water itself but from the pipes it travelled through, corroded by water chemistry that was never properly managed.

Flint became shorthand for infrastructure failure and environmental injustice. But it was also a clarifying moment for something scientists had known for decades: there is no safe level of lead exposure for children. Not anywhere near the levels found in Flint. Not at any level the CDC has ever used as a "reference value." The lead-IQ relationship, in study after study, goes all the way down to zero.

Lead doesn't start in the water treatment plant. It gets in on the way to your tap.

The source: pipes and fixtures The primary entry point for lead into drinking water is the home's own plumbing. Lead service lines — the pipes connecting the water main to the building — were standard installation until 1986, when they were banned for new construction. An estimated 6 to 10 million lead service lines remain in use across the US today.

Inside the home, older brass fixtures, lead-tin solder on copper pipes, and chrome-plated faucets with lead components all contribute. Even "low-lead" brass certified after 2014 can contain up to 0.25% lead by weight — enough to leach into water that sits in the pipe.

The corrosion factor Lead doesn't leach significantly into water that's flowing. The risk is water that sits in contact with lead pipes and fixtures — particularly the first draw of cold water in the morning, or water that's sat for several hours. The chemistry of the water itself also matters enormously: Flint's problem was that the new water source was more corrosive than the old one, accelerating lead dissolution from pipes that had been coated with protective mineral deposits.

Who is most exposed Infants consuming formula made with tap water have the highest exposure per body weight. Young children drinking water at home and at school are the next most exposed. Schools built before 1986 may have both lead service lines and interior lead plumbing — a combination that has produced elevated readings in school drinking water testing in cities across the country.

Flint didn't reveal a new problem. It revealed how badly managed an old problem had become — and how little protection existing regulatory frameworks provided.

The crisis began when Flint switched its water source without implementing corrosion control — a basic requirement under the Lead and Copper Rule that was somehow overlooked. The state's initial response was to send residents letters assuring them the water was safe, based on testing protocols that systematically undercounted lead levels by selecting sample sites unlikely to show high results.

What the crisis revealed about the regulatory framework: • The action level of 15 ppb — the point at which utilities must take action — is not a health-based standard. The MCLG for lead is zero. • Sampling protocols under the Lead and Copper Rule allowed utilities to avoid testing the homes most likely to have high lead results. • Compliance with the rule did not necessarily mean safe water. Flint was technically in compliance in some reporting periods while children were being poisoned.

The EPA has since updated the Lead and Copper Rule, requiring utilities to create inventories of lead service lines and replace them — but the pace of replacement is slow. The Biden Infrastructure Law allocated $15 billion specifically for lead service line replacement, but at current replacement rates, some estimates suggest it could take 20 or more years to eliminate all lead service lines nationally.

You cannot rely on your utility's compliance status alone to determine whether your home's tap water is safe from lead. The most protective approach involves testing your own tap.

Testing your tap water Independent lead testing costs $20–50 through certified labs. Collect the first-draw sample in the morning before running any water — this captures water that has been sitting in contact with your plumbing overnight, the worst-case scenario. If your first-draw result is above 1 ppb (the health-protective level used by many experts, well below the 15 ppb action level), investigate further.

The first-flush rule Run your cold water tap for 30 seconds to 2 minutes before using water for drinking or formula preparation if you have any concern about lead pipes in your home or building. This flushes water that has been sitting in contact with lead plumbing. Use cold water only — hot water dissolves lead from pipes significantly faster.

Effective filtration Not all filters remove lead. Look for products certified to NSF/ANSI Standard 53, which specifically covers lead reduction. Pitcher filters such as Brita's Standard filter are not certified for lead removal; their Longlast+ filter is. Under-sink filters and reverse osmosis systems certified to NSF 58 are highly effective.

Check your water system's lead history PollutionProfile's Water Quality feature connects your address to your utility's compliance history and testing data — so you can see at a glance whether your system has a history of elevated lead results and whether your service lines have been inventoried and flagged for replacement.