Ruling Out Danger

  • January 11, 2018

Like many people, Cal State East Bay student David Tanouye had been following the lead poisoning crisis in Flint, Michigan, on national news for weeks.

In an effort to save money, the city of Flint switched its water source from Lake Huron to the Flint River and almost immediately began receiving complaints about the taste, smell and color of the water. In less than a year, tests run by the Environmental Protection Agency and Virginia Tech revealed toxic levels of lead, which is poisonous to all people, but reaps particularly devastating consequences on the developing brains of children.

Flint was declared a state of emergency by former President Barack Obama and communities across the country held up the city as a worst-case scenario — a place synonymous with blight, contamination and disaster. A benchmark by which to feel better about your own neighborhood.

That is, until a Reuters investigation identifying 3,000 lead-contaminated cities across the U.S. was released in December 2016. The East Bay Times was among the first local news outlets to run the story, publishing this headline: “Oakland: Child lead exposure in Fruitvale worse than Flint, Michigan.”

Tanouye was riveted. Unlike Flint, lead had not first been found in the water, but in the blood samples of local children. Newspapers and city officials pointed to the Fruitvale neighborhood’s large percentage of old homes layered in lead paint, and the cross-contamination of surrounding soil and garden beds from the buildings’ chipping, flaking exteriors.

As an engineering geologist for the San Francisco Bay Regional Water Board — and a graduate student struggling to nail down his thesis — Tanouye had a lightning-bolt moment: The bacteria- and contaminant-laden river in Flint and the geological basin that defines the Fruitvale neighborhood were strikingly similar, and both were poor, minority communities.

He turned to his computer.


“I got this email from David,” Assistant Professor of  Earth and Environmental Studies Mike Massey recalls.

“We had been kicking around ideas about his research and were having trouble finding something satisfying. But then I got this proposal from him right after the news broke about Fruitvale and it was this perfectly worded, complete idea — it was beautiful. It was based on something relevant to geology and scientific study, but really inspired by community. I immediately signed off on the project and we started making plans.”

Tanouye’s hypothesis was simple: As a consequence of the shape and geological depression of lower Oakland, the East Bay watershed may have been depositing lead into Fruitvale soil, where in turn children at parks and on trails near water sources might be exposed.

“I wanted to see if the down gradient flow of water was transporting lead into the Fruitvale area, where it was then getting deposited because of the area’s geography,” Tanouye says. “My hypothesis was that hydrogeologic processes, specifically erosion and deposition, could be contributing to the prevalence of lead in the low-lying areas of Oakland, with Fruitvale being in the center.”

After obtaining permission from the city of Oakland to test soil at public parks and on trails, Massey and Tanouye began canvassing the Peralta and Sausal creeks, and sandboxes and play areas at parks using a fluorescent X-ray spectrometer gun to detect lead in soil at levels as low as 20 parts per million. Although the sampling process takes just seconds and is a simple point-and-shoot operation, the pair are among the first researchers to collect information on lead deposits in a city now known as a national hotspot.

And with five sites under their belts and more than 100 data points comprising their ongoing research, they’ve produced the best results imaginable: Almost nothing.  

“It would have been really interesting from a geologic view, to be able to show the process of how lead is transported, so it’s a little disappointing that my hypothesis was inaccurate,” Tanouye says. “But what this means is that lead isn’t getting into the area from natural sources — it’s a result of anthropogenic (human-made) sources. We’re evaluating how much lead occurs naturally and how much may result from our neglect of lower-income communities. This is the application of geological sciences to real-world problems, and that too, is exciting.”

It’s also useful to the city of Oakland and those vested in addressing lead poisoning and prevention issues.

“I hate that we use our children as our lead detectors.”


“I hate that we use our children as our lead detectors,” Cal State East Bay alumnus Larry Brooks says. Brooks, director of Alameda County’s Department of Healthy Homes and a lead-poisoning prevention expert, has been working at a breakneck pace since the Reuter’s report on Fruitvale broke one year ago.

“We wait until a child is poisoned to start an investigation and send a team out, and then we say ‘A-ha! It’s the paint or the soil contaminated by lead paint,’” he says. “We don’t have enough staff to inspect all these homes, and my plea is to parents to actively get their children lead tested. Lead testing in children between the ages of 12 months and 6 years old when their brains are developing is so important because the longer a child is exposed the more likely they are to have brain cell loss, which lowers IQ levels, and in some cases, cause severe learning disabilities that will affect a child their entire life.”   

Brooks is currently championing efforts for a bill that would mandate blood lead testing for all children ages 1-6 years old in Oakland, as well as a handful of other California cities that have been identified as high-risk. Although an attempt by Dist. 20 Assemblymember Bill Quirk to pass a universal blood-testing bill for the entire state was shot down earlier this year, Brooks is now working with a group called the Oakland Get The Lead Out Coalition to advance the call for mandated blood testing.

And until that happens, he’ll be doing everything he can to add to the scant data available on lead deposits in Oakland, starting with Cal State East Bay. Tanouye and Massey’s results may not have been what they anticipated, but by helping to confirm Fruitvale’s lead problem isn’t naturally occurring, their results can be used to support the call for other remediation efforts.  

“[Tanouye] might feel like he didn’t find what he was looking for, but I’d say he found exactly that — he ruled out a potential danger,” Brooks says. “The best play is to always be trying to rule things out, because we do know that there have been neighborhoods that were formerly industrial sites and when we test soil there, it sometimes comes back hot — contaminated. These trails and creeks, whether they’ve been used in the past by industry or for illegal dumping, we need to know about it. And as you’re looking at the lead, maybe you discover arsenic or some other chemical or contaminant that we didn’t know was there. I’m so proud of these Cal State East Bay students who are out there learning about our past and caring about our future.”

“[Tanouye] might feel like he didn’t find what he was looking for, but I’d say he found exactly that — he ruled out a potential danger.”


Tanouye and Massey aren’t done yet. Though their research has generated positive results for the Fruitvale community, they’ve learned something noteworthy about lead itself that the professor says is worthy of more exploration.

“What we’ve found is that there is huge variation on the microscale between lead deposits,” Massey says. “I could be standing in one spot and you could be standing three feet away, and there might be 10 times the amount of lead where you are compared to where I am. The next question is looking at the soil and sediment, the shape of the stream channel and other factors, and trying to figure out why there is so much small-scale variation.”

While Massey is careful to emphasize that none of the lead found surpasses the recommended safety level of parts per million, his and Tanouye’s method of quantifying the lead in Fruitvale differs significantly from the only other assessment they were able to find on the area.

“There’s one other paper that looked at lead contamination in Oakland from UC Berkeley in 2012, which we’ve cited in our research,” Massey says. “But they used a method that took a bunch of samples, mixed them up and came up with an average number for how much lead is in a designated area. And that doesn’t tell us very much about how lead behaves so we'd like better data in order to make better predictions about where we might find it and where there might be risks.”

Tanouye, who recently presented on his and Massey’s findings at the American Geophysical Union’s annual conference in New Orleans, believes the answer to learning more about lead is a matter of unlocking the secrets of soil.

“It’s the composition of the soil that [determines] how the lead is accumulated and whether it’s mobile,” Tanouye says. “Numerous factors can change the chemical and physical makeup of the soil, which has a direct effect on lead content. There just really isn’t a lot of data out there — that information usually only comes as a consequence of a cleanup or redevelopment. I’m hopeful that we can add to the conversation that helps characterize and predict lead contamination before it happens.”