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Skewed Sampling Persists in St. Louis Lead Contamination Testing

Riley Beggin
Number of lead in water tests done since 2005 by the City of St. Louis Water Division mapped by ZIP code.

The water crisis in Flint, Michigan has turned the national spotlight on lead risks in drinking water across the country. That spotlight has exposed widespread problems with the system that tracks and tests for lead in water systems. KBIA’s investigation into these regulations has found that even if your water utility follows every EPA regulation, you could still be in danger for exposure to lead.

  One such utility is here in Missouri, anchored on the banks of the Mississippi River. St. Louis has never exceeded federal lead levels like Flint, and the city utility follows EPA regulations closely. However, St. Louis citizens, and citizens across Missouri, are still at risk due to lax federal requirements and regulatory loopholes.

A KBIA analysis of St. Louis Lead and Copper monitoring data and blood lead level data from the Missouri Department of Health and Senior Services has also found that over the past ten years, the utility has done over 90 percent of its testing on the south side of the city, where blood lead levels in children are generally lower than they are on the north side.

Lead service lines

The root of the problems in Flint are pipes made out of lead, which were used for plumbing until the 1930s. These lead pipes are called service lines, and they connect your home to the water main that brings water from the city to your house. In St. Louis, as is the case in most cities, homeowners own their service lines.

By the late 1800s, lead service lines were a known cause of lead poisoning. However, the cheap and abundant availability of lead combined with persistent lobbying from the lead industry prompted plumbers to continue to install lead pipes for decades. Installing lead service lines didn’t even become illegal nation-wide until 1986.

In 1990, the American Water Works Association conducted a survey of known lead service lines, and found 3.3 million across the country. Some experts now estimate that that number is closer to 7.3 million. Missouri was among the states the AWWA listed as having one of the highest numbers of these pipes.

According to a survey from the Manual of American Water Works, St. Louis was the largest of several Missouri water systems to be built with all-lead service lines.

“That was standard technology at one point,” said Curt Skouby, Director of Public Utilities for the City of St. Louis. “In the ‘30s I think they switch over to copper on service lines. Probably before that they were all leaded.”

In St. Louis, nearly 75 percent of homes were built before 1930.

How lead gets into drinking water

Without proper water treatment, these lead service lines can be a big problem.

“From a health standpoint, there’s no amount of lead that is healthy for a body to ingest,” said Chris Whitley, a public affairs spokesman for EPA Region 7, which oversees Missouri and three other states.
For young children and expectant mothers, the impact of lead consumption can be especially devastating.

“We’re talking about developmental defects, nervous system developmental issues, diminished IQ… there are lots of potential negative impacts from exposure to lead,” Whitley said.

Unlike most contaminants, lead gets into drinking water at the end of the system, meaning water utilities can’t catch lead in water at the treatment plants. Water is pushed through the city’s water mains, then gathers lead as it goes through the pipes between the main and your faucet. If a home has lead service lines, or even lead solder or fixtures, they could corrode and leach lead into water.

Most water sources have naturally corrosive water, so most utilities—including St. Louis’—treat their water with anti-corrosion chemicals like orthophosphate that prevent lots of lead leaching out of the pipe.

Though chemical treatment drastically lowers the amount of lead in water, it cannot fully prevent lead leaching. Dr. Marc Edwards, a researcher at Virginia Tech and one of the nation’s foremost experts on lead in drinking water, said that most American styles of chemical corrosion control are not strong enough to fully protect people.

“[Corrosion control] absolutely does not stop lead leaching from the service lines,” Edwards said. “In general we’re finding that even with corrosion control in its current form, it’s not reducing the lead release to an extent that satisfies me. If you have a lead pipe in front of your house, you probably can’t trust the water.”

In England utilities use a similar corrosion control that is three times stronger, Edwards said. It is more expensive, but more effective for protecting people against their lead pipes. The dilemma with this treatment style is that the main chemical type used—orthophosphates—can be harmful to lakes and rivers, so EPA puts a cap on how much can be used.

Lead can also be physically shaken from the inside of pipes, which often happens when there is construction on a nearby water main, when a water main breaks or during a partial pipe replacement.

Skouby said that St. Louis has around 300 water main breaks every year.

“EPA is certainly concerned about the overall age and condition of water infrastructure all over the country,” Whitley said. “There’s always the potential that as they deteriorate, they would leach lead or copper into the water that ends up being consumed.”

What’s more, very few cities—including St. Louis—know where the service lines in their city are. Because service lines belong to the individual homeowner and they weren’t considered a threat for many years, most cities did not record the plumbing materials of homes as they were built.

“That’s something historically we haven’t really paid much attention to,” Skouby said. “Up to the 1930s, no one thought there was a health issue with it, so it wasn’t something anybody kept record of.”

Whitley and Edwards agree that not knowing where service lines are can be a problem. When utilities don’t know where the lead service lines in their city are, they would have a harder time warning residents about the dangers they could face in their tap water if there were problems.

Trouble with sampling

Theoretically, utilities catch lead that leaches from pipes by complying with the Lead and Copper Rule, the 90’s-era EPA regulation that requires utilities to test regularly for lead. If utilities don’t meet the standards, they have to take further measures to ensure safety, including implementing corrosion control or considering pipe removal projects.

However, research has shown that the current Lead and Copper Rule is not adequately equipping utilities to conduct accurate water sampling and testing, which can lead to false assurances for homeowners.

Edwards and his colleagues lead the Flint Water Study, a group that has been working to resolve scientific and policy considerations following the crisis in Flint. Edwards worked on a study published in 2012 that found six different instances within the EPA-approved testing process where lead particles could be partially removed from the water sample.

“There are many ways that sampling instructions can miss lead in water,” Edwards said. “We’re finding problems with all phases of lead and water, quantifying the risk. We’ve actually identified samples with as much as 1,500 parts per billion lead that only measured seven (parts per billion) because of the flawed sampling.”

Although there is no healthy amount of lead to consume, the federal action level for lead is 15 parts per billion. If more than 10 percent of sampled homes have lead levels higher than 15, the utility will be required to make changes to its existing policy.

One of the testing mistakes Edwards’ team found was that switching the water sample from its original bottle to another before testing can miss 40 to 100 percent of lead in the sample. City Water Chemistry Manager Jim Kopp said this is a practice that St. Louis’ laboratory does every time it tests.

Because St. Louis consistently tested underneath the action level when the Lead and Copper Rule was implemented, it is now only required to test 50 homes every three years.

The case of St. Louis

St. Louis is not ignoring the threat of lead service lines. Like most cities, it treats its water with the corrosion chemicals that prevent the majority of lead from leaching into the water. Unlike twenty other water utilities in Missouri alone, St. Louis’ tests have never exceeded the action level for lead in water.

On top of that, Dr. Daniel Giammar, a professor of environmental engineering at Washington University in St. Louis, said the chemistry of the river water sent to local homes is naturally resistant to the corrosion that causes lead leaching.

“St. Louis is a little bit unique because our water is so non-aggressive towards corrosion of the pipes,” Giammar said. “It’s a ‘if it isn’t broke don’t fix it’ kind of situation.”

Nonetheless, he said that having lead service lines always leaves the possibility that some lead will get in the water, and that there is a lot of room for improvement when it comes to sampling practices.

“I think that overall our testing procedure could be a lot better,” Giammar said. “I don’t think we’re really missing a problem by doing this, it just means that our data are—the word we would use in research is ‘noisy’.”

Put simply, the data showing safe levels of lead in drinking water are not entirely reliable.

One issue lies in the sampling instructions. Documents provided to KBIA by the Missouri Department of Natural Resources show that both the St. Louis City and St. Louis County utilities ask homeowners to “slowly” or “gently” fill their sampling bottle. According to Giammar, samples should be collected at the rate one would normally fill a glass of water—slower rates can leave lead undetected.

According to drinking water experts, inconsistent sampling is an issue across the country. Other required sampling protocols include taking the first draw of tap water after it has sat in the pipes for at least six hours, using a wide-mouthed bottle and drawing cold water. That means that homeowners can’t get a glass of water or go to the bathroom in the middle of the night, otherwise their sample will be invalid. Because homeowners take the sample themselves, it is up to them to ensure that they are drawing the most accurate sample possible with their city’s instruction.

Another issue lies in the location of water sampling. Blood lead level data from the Missouri Department of Health and Senior Services shows that there are neighborhoods on the north side of St. Louis where lead poisoning in children is high year after year.

Meanwhile, the majority of the city’s water sampling over the last ten years has not come from those neighborhoods, but from south-city neighborhoods that do not have as significant a problem with lead poisoning in children.

The demographic differences between these two areas are significant, too: The people that live in the southern neighborhoods are more frequently white and middle-class, and the people in the northern neighborhoods are mostly black and lower-income.

Skouby said that targeting south city neighborhoods was not intentional.

“If anything, it is how we found the volunteers willing to do it,” Skouby said. “A lot of times there’s a connection, people that we know or know through somebody that we can ask if they are willing to do it. The same water quality goes throughout the city, and chemistry-wise it should be the same regardless.”

Dr. Yanna Lambrinidou, an affiliate faculty member in the Department of Science and Technology in Society at Virginia Tech, said that a variety of factors can make one set of homes with lead service lines test low for lead, and another set of homes test high for lead in the same water system.

“I think that the neighborhoods where there seems to be a greater concentration of children with elevated blood lead levels should really be the gold standard for water utilities to focus on in their sampling,” Lambrinidou said.

Skouby also said that they don’t target areas with high blood lead levels because many homes in the area have lead paint, which is a well-known cause of lead poisoning.

“The city has a pretty aggressive program for reducing lead levels in children,” Skouby said. “They’ve been monitoring it and they’ve been pretty successful—it’s attributed to the lead paint in the homes.”

Lead-based paint is the largest contributor to elevated blood lead levels in children across the country. However, a study published in the American Journal of Public Health said that 10 to 20 percent of lead poisoning in children, and 40 to 60 percent of lead poisoning in formula-fed infants can be traced back to water.

National Drinking Water Advisory Council meeting notes have also suggested that there is a link between elevated blood lead levels in children and lead in water, especially when inspectors found that the home did not have lead paint.

John Carrico, the program manager of the city’s Lead Remediation Program, said that they do not check for lead in water when they do inspections because that is under the purview of the water division, and it is not paid for through the department of Housing and Urban Development.

Cities like Chicago that have a similar problem with lead poisoning in poor, majority-black communities are changing their testing policies to target testing in at-risk neighborhoods.

Lambrinidou said that even when sampling is done appropriately, the unpredictable nature of lead service lines can make sampling a lot like Russian roulette.

“The way in which lead in water releases tends to be unpredictable and tends to fluctuate,” Lambrinidou said. “You can go and use the same tap ten different times, fill up a glass of water and your water might be perfectly safe with non-detect levels of lead all ten times. Then you go back, and the eleventh time you’ve caught a chunk of lead—a lead particulate—that has happened to fall into the water right at the time you were filling up your glass.”

In order to test the unpredictability of the sampling process, KBIA worked with Giammar’s lab to conduct some spot testing. Ten homeowners—five on the south side of the city and five on the north side of the city—provided us with water samples that were tested according to EPA sampling protocol.

We made sure to follow some of the protocols Edwards and others say are better than the EPA’s current processes. For example, we asked the homeowners to take the sample at the rate they would fill a glass of water, not “slowly” or “gently,” as the city currently requires.

It became obvious that it is difficult to get a good sample. Finding the right houses, getting people to agree to do the tests and making sure the homeowners followed the instructions was a tedious process.

When our test results came back from the lab about a month later, they showed very low levels of lead in the drinking water of the homes we tested from both the north and south side.

The results are good news for those homeowners. However, the small sample size speaks to Lambrinidou’s comparison of sampling to Russian roulette. We did 10 tests; the city of St. Louis does 50 tests every three years. Some cities need to test more homes more often than that, but because St. Louis has complied with the Lead and Copper Rule since it began, the testing is less stringent.

Bureaucratic changes ahead

EPA is currently in the process of revising the Lead and Copper rule to better protect people from lead in their water. EPA began that process in 2010. They have known about problems with their regulations since at least 2004, when a drinking water crisis in Washington, D.C. prompted the agency to begin looking into the effectiveness of how the Lead and Copper Rule is implemented.

Lambrinidou served as a member of the Lead and Copper Rule Working Group, a board of scientists, NGOs and utility representatives that have been discussing the best possible changes to the rule over the past two years.

She said there are four major areas that her group sought to address that, combined, make the testing process really unreliable: public education about lead in water, sampling procedures, the effectiveness of corrosion control treatment and the remedial measure of lead service line replacement.

A water system is only required to start replacing its lead service lines if it has exceeded the lead action level and its corrosion control treatment is failing. Some cities have considered replacing service lines before they are required to as a remedial measure.

Even the concept of Lead and Copper Rule compliance as it currently exists leaves room for lead poisoning to go undeterred. Up to 10 percent of samples in a utility’s service area can have any amount of lead—it is not until the ratio of poisoned homes goes beyond 10 percent of the samples do any changes need to occur.

“The Lead and Copper Rule requires water utilities to address widespread city-wide contamination, when such contamination is detected,” Lambrinidou said. “So you can have utilities that meet the rule requirements, and at the same time you can have individual homes within the service area of these water utilities with astronomical levels of lead in drinking water.”

The working group’s official recommendations were presented to EPA in late August last year. The revisions will go through another round of editing – depending on how long that takes, it could be implemented in 2018 or beyond. Edwards says that until Flint, EPA did not insist upon any major changes to policy until the revision officially came into effect.

“It’s just been incredibly frustrating to push and push and for EPA to sit there and claim they can’t do anything until the revision is in place,” Edwards said. “The revision is going to be a decade overdue by the time it comes.”

Edwards said that utilities, state departments of natural resources and EPA need to change their attitudes.

“It’s viewed as bad news if you find high lead in water,” Edwards said. “[Cities] want to cover it up. Instead, what they should be doing is telling people about the problems with lead in their system honestly and openly, so that they can take simple strategies that are inexpensive to protect themselves and their children if there are problems.”

What homeowners can do

For people that have lead pipes, the easiest way to lower the risk of lead exposure is to drink filtered water, and to run tap water for several seconds or minutes before drinking it. Many local water utilities offer individual testing at a low cost, and people can hire a plumber to help determine the makeup of their piping.

Another option is to replace the lead service lines. This can be a large barrier for low-income families—or any family, for that matter—as replacing each service line can cost up to $6,000. Giammar said that if people decide to replace service lines, they need to take some precautions to make sure that even more lead isn’t let loose into their system. Disruption of lines is a common cause of lead exposure.

“If you’re going to [replace your service lines], two things: You don’t want to do a partial lead service line replacement. Second, if you do it, you need to be sure you flush and test after that line is removed,” Giammar said.

Some cities have opted to help their citizens pay for the removal of their service lines, though it can be a controversial solution. As Skouby explained, it raises the question of who is responsible for addressing issues with privately-owned lead lines.

“The lead service lines, we don’t own them,” Skouby said. “They’re private property, we’re a public agency. Spending public funds on private property is problematic.”

Skouby’s viewpoint is just one in a complex national conversation about lead in drinking water following the crisis in Flint. Government entities, scientists and local utilities all have their own opinions about how to best combat this issue. St. Louis, and cities like it, are working within the guidelines of EPA regulations, which are long overdue for change.