Poor Black Baltimore Families Used as Human Guinea Pigs in Sludge Study

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Poor Black Baltimore Families Used as Human Guinea Pigs in Sludge Study: "In 2000, nine Baltimore families -- all black residents of the city's east side -- received food coupons in exchange for permission to allow researchers to spread "Class A" Baltimore sewage sludge (brand name, Orgro High Organic Compost) on their yards, till it into the soil and then plant grass seed.

"The rationale for this experiment was to find out whether municipal sewage sludge could lower the amount of lead that children who played in the nine experimental yards would absorb. Veolia Water, the corporation that markets Baltimore municipal sludge as Orgro, claims its "beneficial biosolids" are so safe they are even used on the White House lawn.

An Associated Press article provides more information, including that the families "were assured the sludge was safe and were never told about any harmful ingredients." The study was conducted by the USDA, the EPA, and Johns Hopkins University over two years, using a $446,231 grant funded by the Housing and Urban Development Department. The principal investigator in the study had a joint appointment with the Bloomberg School of Health at Johns Hopkins and the Kennedy Krieger Institute in Baltimore. The study was published in 2005. Due to privacy concerns, the study participants (the Baltimore families) were not identified. However, "there is no evidence of any medical follow-up" by the government after exposing the families to sewage sludge.

Researchers claimed that "the sludge... put the children at less risk of brain or nerve damage from lead. A highly toxic element once widely used in gasoline and paint, lead has been shown to cause brain damage among children who ate lead-based paint that had flaked off their homes." They added that "the phosphate and iron in the sludge can bind to lead and other hazardous metals in the soil, allowing the combination to pass safely through a child's body if eaten."

The AP adds:

"There has been little research, meanwhile, into possible harmful effects of heavy metals, pharmaceuticals, other chemicals and disease-causing microorganisms often found in sludge. A series of reports by the EPA's inspector general and the National Academy of Sciences between 1996 and 2002 faulted the adequacy of the science behind the EPA's 1993 regulations on sludge."

Associated Press Investigation

John Heilprin, who co-authored the AP story, said, "Well, at root, the problem that I see is that the material in question that the used, no one can prove that the material is safe. That's the essence of it." Later in the interview he added: "But, you know, at root, all this material that we're talking about in this particular case comes from a waste water treatment plant in Baltimore. Like every other city, it takes in tens of thousands of organic pollutants, heavy metals, pathogens, PCBs, etc. It sends them to processes. This fertilizer we're talking about is a more highly treated form. However, at root, nobody can say on any given day what exactly is in this stuff." (emphasis added)

He continued, saying:

"Well, we've been taking a look at sludge for over a year now. And EPA permits two classes of what's called sewage sludge - or biosolids is the preferred term by the industry - Class A, Class B. The Class B is more commonly used for agricultural products. The Class A, which was used for the study, is more highly treated. And in this case, it is sold at nurseries, hardware stores, at the proponents say, it's used in the White House lawn, or it has been. However, the treatment level is that they kill off indicator pathogens, like E. coli and salmonella. They do not kill all the pathogens. And they kill them to detectable levels, which means that there may be some left. That's the essence of it."

Farai Chideya asked him, "One of the questions that has arisen is the question of consent. You know, when you agree to be part of a study, how do you agree? Do you understand what's going on? What's your understanding of how the people who were approached, the families who were approached, were given information to make a good decision about what they did?"

Heilprin replied, "Well, you know, first of all we try to find the participants and nobody would tell us their identities. We had to send a Freedom of Information Act request to Department of Housing Urban Development to get some documents. The Kennedy Krieger Institute referred all questions to Hopkins. We finally got a few answers from them, but not the participants. So what we were told was that they were given brochures on the dangers of lead contamination, which is a problem in a city like Baltimore, with aging housing. And that they were told that the fertilizer was a commercially grade fertilizer, sold in the state of Maryland and that there wasn't any danger to it."

Response from Johns Hopkins

Dr. Michael Klag, Dean of the Bloomberg School of Health at Johns Hopkins University said the study was done in Baltimore because "Baltimore was in an epidemic of lead poisoning. And in the area where this study was done, elevated blood levels in children were 35 to 40 times higher than the national average... Kennedy Krieger Institute was looking at how to prevent this epidemic in the areas that were most affected."

When asked whether the sludge was safe, he replied to NPR's Farai Chideya, "Let's be clear. The controversy you are referring to refers to sludge, the type B bio-solvent. This is type A. So this is compost that you can buy at any garden store. The state environmental regulations here are much stricter than the EPA and this product was far below those standards. So I think one of the issues was with the initial report is there was confusion between the type A bio solvent and the type B. So the anecdotal reports which have been put out about harm have related to the type B."

His distinguishing between Class A Biosolids and Class B Biosolids is dishonest, as the only differences between Class A and Class B are allowable levels of two pathogens, fecal coliform and salmonella, and "vector controls" on Class A biosolids. (Vector controls refers to ensuring the sludge does not attract insects or rodents that transmit disease.) Yet he continued, saying: "Well, I think it was inaccurately portrayed in the press. It was portrayed as putting toxic sludge on the lawns of poor people to experiment on them, and it's just not true."

On its website, Johns Hopkins wrote that "In 2005, the results of this groundbreaking study were published in a peer reviewed journal and its success provided a tool to policymakers for cost-effective remediation of lead contaminated soil, in urban neighborhoods."

It explained the lack of medical follow-up as follows:

"The research premise was to study by how much the compost could reduce the levels of “bio-accessible” lead in the soil. It was not to study the people affiliated with the study site. All children were required by Baltimore City law to be tested for lead levels by their primary care physician, and the materials given to study participants encouraged them to have their children tested and advised them that they could get free blood testing.

"Further, there was no need to conduct medical follow-up related to the use of the compost since there was no evidence then, nor now, that this commercially available, general use product posed any health risks."

John Hopkins said the following about participants consent and compensation:

"Participants signed a consent form which included very specific detail on the study, including the compost used. As always in such studies, a qualified member of the study team walked through the details of the study with participants, and answered all questions. Participants were given as long as they wanted to decide to allow their yards to be tested.

"Participants were given $10 gift certificates to local food stores in exchange for allowing treatment of their yards as part of the study. Testing took time and they needed to be home. The gift certificate compensated them for their time – a routine practice in most studies."

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