COMMENTARY: MDEQ Mistakes and Deception Created the Flint Water Crisis

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As results of collaborative research with Flint residents exposed widespread problems with elevated levels of lead in Flint’s water, the Michigan Department of Environmental Quality (MDEQ) repeatedly attempted to discredit our findings and downplay the public health threat. For example, MDEQ’s Communications Director Brad Wurfel wrote to The Flint Journal’s Ronald Fonger:

“…the state DEQ is just as perplexed by Edwards’ results as he seems to be by the City’s test results. When I said we were unsure how the Virginia Tech team got its results, that’s not the same as being surprised that they got them. …this group specializes in looking for high lead problems. They pull that rabbit out of that hat everywhere they go. Nobody should be surprised when the rabbit comes out of the hat, even if they can’t figure out how it is done…..while the state appreciates academic participation in this discussion, offering broad, dire public health advice based on some quick testing could be seen as fanning political flames irresponsibly. Residents of Flint concerned about the health of their community don’t need more of that.”

Now that Dr. Mona Hanna-Attisha and Hurley Medical Center researchers have revealed that the rising levels of lead in Flint water have been associated with increased blood lead of Flint’s children, our early health advice has been vindicated by most accounts. But MDEQ still dismisses the water controversy as “near-hysteria,” and characterizes the Hurley study conclusions as “unfortunate” if not quite “irresponsible.”

Given MDEQ’s insistence that there is absolutely nothing wrong with Flint water, we have created a timeline that illustrates how MDEQ’s mistakes and deception created the Flint Water Crisis in the first place. Our analysis relies on e-mails and documents obtained through Freedom of Information Act (FOIA) requests by the American Civil Liberties Union-Michigan (ACLU of Michigan) and FlintWaterStudy.org.

All FOIA documents are provided at the end of this article for review.

Phase 1. MDEQ Fails to Require Corrosion Control for Flint River Water (April 2014)

Effective July 1998, the federal Lead and Copper Rule (LCR) has required that all large public water systems maintain a program to control levels of lead in drinking water from corrosion. Moreover, the law also requires the City of Flint to have a state approved plan, with enforceable regulatory limits for “Water Quality Parameters” including pH, alkalinity and/or corrosion inhibitor dose measured in the water distribution system.

MDEQ never required Flint to have a corrosion control program, nor did it set water quality parameters for the new Flint River source water. While MDEQ asserts that they are acting proactively to get a corrosion control program in Flint, there is no provision in the LCR that allows for corrosion control to ever be interrupted.

As a direct result of this mistake, Flint residents have been completely unprotected from elevated lead in water from the moment the switch to Flint River water was made. This has created a conflict of interest for MDEQ ever since. Specifically, MDEQ’s failure to require a corrosion control program is what created the Flint water crisis in the first place–they now have a vested interest in covering up the problem.

Phase 2. MDEQ misinforms the USEPA about Flint’s Corrosion Control (February-March 2015)

Even if we assume MDEQ was confused about its obligations under the LCR, when problems with high lead started to crop up in February 2015, they should have quickly acted to correct the mistake. Samples with high lead were reported at the University of Michigan-Flint Campus, and on February 26, 2015 Mike Glasgow (City of Flint) did excellent detective work discovering high lead (over 100 ppb) in water samples from Flint resident Lee-Anne Walters’ home.

Ms. Walters immediately forwarded her results to representatives of USEPA Region 5, who in turn immediately forwarded the results to Stephen Busch and Mike Prysby (MDEQ) with the subject line “HIGH LEAD: FLINT Water testing Results” The EPA e-mail correctly informed MDEQ that Ms. Walters’ high lead was likely due to “… the different chemistry water…leaching out contaminants from the insides of…the pipes.” But MDEQ denied to EPA that that Flint had a lead in water problem.

At that point, EPA Region 5 lead-in-water expert Miguel Del Toral asked MDEQ a question through another EPA employee:

“Miguel was wondering if Flint is feeding Phosphates. Flint must have Optimal Corrosion Control Treatment-is it Phosphates?”

On February 27th, 2015, MDEQ’s Stephen Busch unequivocally and falsely responded to EPA that:

“The City of Flint…Has an Optimized Corrosion Control Program <and> Conducts quarterly Water Quality Parameter monitoring at 25 sites and has not had any unusual results.”

Reassured by MDEQ’s false statement, Del Toral ended USEPA’s February conversation with MDEQ by stating:

“If I remember correctly, Detroit is feeding PO4 for the LCR, but since Flint is no longer part of that interconnection, I was wondering what their <Optimal Corrosion Control> was. They are required to have <Optimal Corrosion Control> in place which is why I was asking what they were using.”

On March 18, 2015, Lee-Anne Walters’ home was retested after flushing her system thoroughly. This time the test result came back even worse with 397 ppb lead– almost 40 times higher than the World Health Organization 10 ppb safety threshold. EPA Region 5 forwarded the results to MDEQ, with a query “Any thoughts on how to respond to her? I’m running out of ideas.”

MDEQ’s response, delivered in a voicemail to Del Toral on March 19, 2015, stated that MDEQ had investigated and found Ms. Walters’ high lead was due to lead sources in her plumbing. On March 27, 2015, Walters’ son, who had been having health problems, was tested for lead in his blood. The blood lead results came back high– well over the 5 ug/dL CDC threshold of concern.

Phase 3. Walters and Del Toral Investigate the Veracity of MDEQ Statements (April to June 2015)

With good reason, Lee-Anne Walters did not accept the MDEQ’s explanation to Del Toral for the high lead in her water. The internal plumbing had been stolen from the house before it was purchased, and they had installed new (lead free) plastic plumbing before moving in.

Walters also checked up on the MDEQ statement that Flint had “an Optimized Corrosion Control Program.” She called the City of Flint, and city officials correctly informed her that there was no program at all.

Walters then passed this alarming information along to EPA’s Del Toral, who on April 23rd e-mailed MDEQ, and again asked what corrosion control program Flint was using. It was only then that MDEQ finally acknowledged that there was NO program. Concerned due to the very high occurrence of lead service lines (LSLs) in Flint, on April 27th Del Toral wrote an EPA Region 5 internal e-mail stating:

“Flint has not been operating any corrosion control treatment, which is very concerning given the likelihood of LSLs in the City.”

That night Del Toral also stopped at Walters’ house on a trip north, and personally inspected her plumbing first hand. He confirmed it was plastic and lead-free. Del Toral also dropped off sample bottles at the Walters’ home, and told her that if she wanted an analysis to contact Professor Marc Edwards (the author of this article and Principal Investigator of FlintWaterStudy.org) at Virginia Tech.

The next morning Edwards talked Walters through an intensive 30 bottle sampling protocol. When the bottles were returned to Virginia Tech and analyzed, Edwards and his senior research scientist Dr. Jeff Parks were stunned by the results. The average lead in was 2,429 ppb lead, the high was 13,200 ppb, and even after 25 minutes flushing the water never dropped below 200 ppb. After Walters told Del Toral about the high lead results, he drove back to Flint, just in time to observe the City replacing the service line to Walters’ home. He personally collected a sample of the pipe and verified it to be pure lead.

In a follow-up memo dated June 24, 2015, which was sent to both Walters and Edwards, Del Toral outlined numerous concerns about the situation regarding the serious lead corrosion problem in Flint. He included a clear recommendation that the USEPA investigate whether the City of Flint was in compliance with federal laws for lead corrosion control.

Phase 4. MDEQ “Handles” the LCR Report, ACLU-Michigan, Virginia Tech and Miguel Del Toral (July to August 2015)

> “Revising” the Original LCR Report. In spite of all the problems documented with lead in Flint water from February to June 2015, Flint and MDEQ took a lackadaisical approach to the federally required LCR sampling program. Specifically, just 5 days before the June 30th deadline to collect the 100 samples that MDEQ required, the City had only collected 39 samples.

Adam Rosenthal (MDEQ) e-mailed Mike Glasgow at the City of Flint:

“We hope you have 61 more lead/copper samples collected and sent to the lab by 6/30/15, and that they will be below the AL for lead. As of now with 39 results, Flint’s 90th percentile is over the AL for lead.”

In the next five days the City collected 30 samples, all of which were below the action level, and did not reach the 100 sample target. If all 71 collected samples were counted, the City would have exceeded the 15 ppb action level. Federal law would then require that Flint residents be provided information about how to protect themselves and their children from lead in water. MDEQ’s failure to install corrosion control would have been flagged as an obvious mistake. But none of that happened.

Instead, the MDEQ “revised” the City’s original LCR report, invalidating two high lead results, and as a result the 90%’ile was under the 15 ppb action level. But validity of the samples that had low lead in Flint’s water was never questioned. This is a problem, because the City has now admitted that they do not know which homes had lead pipe, even though it is stated in writing in the report that all sampled homes had lead pipe. By law, at least 50 percent of the homes sampled must be verified to have lead pipe, and the remainder of homes sampled must have been built before 1986 and known to have lead solder. There is no basis for believing that this requirement was met in either the 2014 or 2015 LCR sampling events conducted by the City. Hence, the City of Flint has not had a valid LCR sampling event since the switch to Flint River water.

MDEQ then lowered the minimum number of required samples from 100 to 60, making it look like the City of Flint had met their target. MDEQ also did not question the City’s open acknowledgement that homes from 2014 had not been re-sampled, or that high risk (Tier 1) sites were not used. The original report, due July 10th, was also late by several weeks. All of these violations of federal law were glossed over, to make it appear that the City had passed its lead testing with flying colors. Just like that, according to MDEQ at least, the City of Flint had no LCR violations at all.

> ACLU-Michigan FOIA. The timing by which the “revised” LCR report was created, is also of interest. On July 22, 2015, the ACLU-Michigan submitted a FOIA to MDEQ, requesting the City of Flint’s LCR report supposedly due on July 10, 2015. The City’s original LCR report with all the obvious problems dated July 28, 2015 was late as mentioned earlier. But MDEQ never provided the ACLU-Michigan with the original LCR report. Instead, they created a scrubbed revised report on August 20, 2015, and sent that report to ALCU-Michigan (from the City of Flint) the next day. In the comments section of the report, Flint openly states “Revised report after conference call with DEQ staff. Two samples were removed from list for not meeting sample criteria, and due to population the number of samples was reduced to 60.”

> MDEQ to FlintWaterStudy FOIA: What conference call? On September 9, 2015, Virginia Tech submitted a FOIA to MDEQ explicitly requesting records and minutes of the conference call between DEQ staff and Flint cited in the revised LCR report. This FOIA request has been denied by MDEQ, because “Your request does not include the date/time of the conference call and who from the Department of Environmental Quality participated on the conference call.” FlintWaterStudy immediately appealed the withholding of documents related to the conference call to the State of Michigan. On September 28th, our appeal was denied. If we do not like the decision, the State says our only recourse is to initiate a lawsuit.

> Handling Miguel Del Toral. MDEQ obviously had a major problem on its hands with EPA’s lead-in-water expert Miguel Del Toral. On August 4th 2015, Lee-Anne Walters and Melissa Mays met with MDEQ officials to discuss Flint’s lead in water problems. The MDEQ officials participating in the meeting were identified by Mays and Walters, as Liane Shekter-Smith (Chief of the Office of Drinking Water and Municipal Assistance), Stephen Busch and Brad Wurfel.

According to Walters and Mays, Shekter-Smith bragged that “Mr. Del Toral has been handled,” and that Flint residents would not be hearing from him again. Moreover, MDEQ asserted that Mr. Del Toral’s interim memo detailing the many problems with Flint’s (non-existent) corrosion control program “would never be finalized.” Just yesterday, NPR released a slightly different, but enlightening version of Wurfel’s take on Del Toral and the memo:

MDEQ spokesman Brad Wurfel says the report was the work of a “rogue employee,” and promised the final report — not yet released — would tell a much different story.

Mays and Walters vividly recall Wurfel, smirking and laughing, whenever they expressed concern about elevated lead in Flint’s water. Looking back on the exchange yesterday, Mays stated “It is shocking how their refusal to admit they made a mistake, trumped the dangers their actions pose to Flint’s children.”

Angered, Lee-Anne Walters then called Edwards, and informed him that Del Toral would no longer be working on Flint water issues, and the two discussed the clear implication that EPA bureaucrats had intervened to prevent Del Toral from further exposing MDEQ’s numerous blunders and the health threat to Flint residents. She further stated that “It is too late for my son, but I will not stand by and let this happen to another other innocent child in Flint.”

Clearly, the MDEQ, City of Flint and even the USEPA (with the obvious exception of Del Toral) have proved themselves unworthy of the public trust. Flint residents have been left to fend for themselves, when it comes to dealing with the dangers of high lead in their water.

FlintWaterStudy was launched an hour after the phone call from Ms. Walters, to help the citizens of Flint deal with the lead-in-water crisis that MDEQ created, and to correct false statements from uncaring agencies that have left Flint’s children in harm’s way.

FOIA Documents:

Emails between MDEQ, USEPA, and Ms. LeeAnne Walters:

Download (PDF, 169KB)

Original LCR Report from City of Flint to MDEQ:

Download (PDF, 94KB)



Revised LCR Report from City of Flint to MDEQ:

Download (PDF, 357KB)

FlintWaterStudy.org’s FOIA Appeal Denied:

Download (PDF, 15KB)

Primary Author: Dr. Marc Edwards

Acknowledgements: Curt Guyette, LeeAnne Walters, Melissa Mays, Siddhartha Roy

Public Health Advisory regarding Lead in Flint Water from the Genesee County Board of Commissioners, Health Dept and City of Flint

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Earlier this morning, the Genesee County Board of Commissioners released the following public health advisory for residents concerning lead in Flint Water:

Download (PDF, 787KB)

Here is the FAQ sheet on lead from Genesee County Health Department:

Download (PDF, 178KB)

Also, the Lead Advisory issued by the City of Flint on 9/25/15:

Download (PDF, 211KB)

In other news, Genesee Health Coalition launched flintwaterinfo.com late last week with advisory precautions on lead. These are very similar to the advice we gave out. It is good news that there is now a website dedicated exclusively to lead in drinking water risks for Flint residents.

Research Update: Corrosivity of Flint Water to Iron Pipes in the City — A Costly Problem

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Immediately following our research trip to Flint in mid-August, we began experiments to quantify the relative corrosivity of Flint River Water versus Detroit water. These tests are done in the laboratory so we can draw definitive conclusions. While such testing is almost always done 6 months to a year before switching a water source to anticipate and avoid unexpected problems, in this case we are doing it more than a year after the switch to examine “What went wrong?.”

Recent news is correctly focused on the very high corrosivity of Flint River water (without any inhibitor) for lead plumbing, and the likelihood that the resulting higher lead in water is associated with increased blood lead for Flint’s children. However, iron corrosion is also a major problem, and herein, we report our final experimental results on this issue. Corrosion in general, and iron corrosion in particular, is the most expensive problem that water utilities face. Rapid iron corrosion can easily cause tens of millions of dollars’ worth of damage per year to Flint’s water mains, so we wanted to examine how bad the problem was.

Hypothesis: It was hypothesized in our National Science Foundation (NSF) proposal, that Flint River water alone would be about 5 times more corrosive than Detroit water. However, no corrosion inhibitor was added to Flint River water, which could make the difference even greater. Morever, certain bacteria that can speed up corrosion, can grow in pipe systems, and essentially cause iron pipe to be “eaten up” faster than without these bacteria. This is called Microbiologically Induced Corrosion (MIC). During our field sampling a month ago, we looked for MIC bacteria in the Flint system versus samples from Detroit, to see if there were problems due to MIC bacteria.

Result #1.   Head to head comparison of iron corrosion in Flint River vs. Detroit Water.

We previously demonstrated that rapid iron corrosion in Flint River water was eating up the chlorine disinfectant, and causing much more iron release than in Detroit water. We continued the same test for a month, exposing steel samples (a nail that is 99.99% iron) to: 1) Detroit water, 2) Flint River water, and 3) Flint River water plus orthophosphate (a known corrosion inhibitor). The water contacting the steel was changed every Monday, Wednesday and Friday. After a month, we photographed the iron samples, and measured weight loss. Each experiment was conducted in groups of three (triplicate) so we could estimate the corrosion rate with statistical confidence.

There was much more rust on the nail exposed to Flint River water compared to Detroit water (Figure 1). This gives you an idea why General Motors had to stop using Flint River water, because it was eating up metal on their assembly line.

Figure 1. Illustrative photograph of a nail after 1 month exposure to Detroit water (above) and Flint River water with no inhibitor (below). Each nail was rinsed in flowing water before taking the picture.
Figure 1. Illustrative photograph of a nail after 1 month exposure to Detroit water (above) and Flint River water with no inhibitor (below). Each nail was rinsed in flowing water before taking the picture.

The weight loss measurements of the nail were used to determine the rate at which the water ate away at the steel, and verified scientific theory and our experimental hypothesis (Figure 2). Flint River water is more corrosive even with phosphate added than Detroit water (which has phosphate). In fact, Flint River water plus phosphate had 3.5 times more weight loss than the Detroit water, which is reasonably close to the theoretical prediction of 5X more corrosive noted in our NSF proposal (Figure 2). Theory says this is due to the higher levels of chloride and sulfate in the Flint River water than in the Detroit water. If an orthophosphate corrosion inhibitor was being added to Flint River water, in the last 16 months the city pipes would essentially have aged about 56 months (56 months = 3.5 faster corrosion X 16 months) more than if Detroit water was used.

Unfortunately, the Flint River water was added to the pipe system without any phosphate inhibitor. In our tests, this condition was 8.6X worse than Detroit water (Figure 2). Assuming this rate applies to the actual city pipe system, the last 16 months on Flint River water would have aged the pipes about 138 months (138 = 8.6 X 16 months) or 11.5 years more than using Detroit water. This could easily be costing citizens of Flint millions and millions of dollars in future pipe repair costs (see later discussion).

Figure 2. Iron corrosion rate based on weight loss after 1 month in Detroit, Flint River, and Flint River water plus orthophosphate (1mg/L as P).
Figure 2. Iron corrosion rate based on weight loss after 1 month in Detroit, Flint River, and Flint River water plus orthophosphate (1mg/L as P).

Result #2: Microbially Induced Corrosion (MIC).

The above results are bad enough, but they do not consider problems caused by bacteria that can further accelerate metal pipe corrosion. When we went to Flint, we brought Biological Activity Reaction Test (BART) kits to look for specific MIC bacteria including: heterotrophic aerobic bacteria (HAB), acid producing bacteria (APB), iron reducing bacteria (IRB), sulfate reducing bacteria (SRB), and slime forming bacteria (SLYM). As a scientist, it is fun to do these tests, because when the bacteria grow one can see colors either appearing or disappearing to indicate that they are present (Figure 3). Depending on how fast the color changes, one can also roughly tell how much of each bacteria type are present—if there are more bacteria the color changes more quickly. For example, HAB tests have a color blue without bacteria (upper left Figure 3) and it will turn clear if bacteria are present and grow (lower left Figure 3). Or the SRB test bottle is clear if there are no bacteria (upper black cap bottle Figure 3) and will turn black if the bacteria are present and grow (lower black cap bottle Figure 3). The key point is that all types of corrosion causing bacteria were found in the Flint system (comparing top bottle with no bacteria to bottom bottle from Flint tap water of the same color cap). This is probably due to low chlorine, but might also be due to Flint River having a lot of organic matter (or “food”) for bacteria in it. We took a few samples of Detroit water, and the levels of corrosion causing bacteria were much lower.

Figure 3. Bacteria tests from right to left for HAB, APB, IRB, SRF and SLYM. The top bottles show what no or low levels of bacteria look like. The bottom bottles (all from the Flint system) show a color change indicating the corrosion causing bacteria are present.
Figure 3. Bacteria tests from right to left for HAB, APB, IRB, SRF and SLYM. The top bottles show what no or low levels of bacteria look like. The bottom bottles (all from the Flint system) show a color change indicating the corrosion causing bacteria are present.

We cannot say for sure that these bacteria were not in the Flint system at high levels if the Detroit water was still being used. But we strongly think that there would have been a lot fewer of them. In general, it is believed that the more MIC bacteria you have, the more problems you will have with excessive iron pipe corrosion. So the earlier estimates of corrosion rate, as bad as they are, might even be worse in the real Flint system when the bacteria are present.

 

Commentary: The High Costs of Pipe Corrosion and Importance of Corrosion Control

As a “back of envelope” illustration of how expensive corrosion is, let’s do some math that is grounded in some real numbers. It has been estimated that it would cost about 1.5 billion dollars to replace all of the pipes in the Flint distribution system. Assuming that cost can be (optimistically) spread out over the next 50 years, the cost per year to Flint residents would be 30 million dollars per year. Assuming there are 30,000 ratepayers, this translates to about $1000 per rate payer per year ($83/month per ratepayer). So right away, you get some insights, into why water rates are so high in Flint!

But now, instead of spreading that payment out over 50 years, it might have to be spread out over only 38.5 years (50 yrs – 11.5 yrs = 38.5 years) because of the corrosion damage done and pipes failing sooner. Remember, we have aged the system 11.5 years or so in just 16 months. This would mean that pipe replacement costs would have to go up to about 39 million a year just to keep up with failures. Thus, costs to ratepayers would be $9 million extra per year for the next 40 years, because of the extra corrosion that occurred by Flint River water without inhibitor.

While this is a very crude analysis, it does illustrate why corrosion problems not only endanger public health, but they are also extremely expensive. Every dollar spent on corrosion control usually saves at least $5-10 in damage, and future repair costs at a typical utility. For Flint, it is quite possible that the damages from corrosive water could ultimately be in the range of a hundred million dollars or even more. On top of that, this analysis does not consider damages to consumers plumbing, which tend to be even more expensive. This is a serious problem indeed, and casts the initial idea that switching to Flint River water would save money in serious doubt. In fact, it is highly likely that the switch will end up costing future citizens of Flint, millions and millions of dollars.

Experimental work and Primary Author: Dr. Marc Edwards

Acknowledgements: Siddhartha Roy

Pediatric Lead Exposure Presentation from Hurley Medical Center doctors concerning Flint MI

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Earlier today, doctors from the Hurley Medical Center presented findings of rise in blood lead levels of children less than 5 years old living within Flint zip codes 48501-48507 after the switch to Flint River water as the source.

Be: Cialis. First we will want to be: Appearance of the first part of the promotion and emotional reaction in mind, many factors, when he first time ask the blood pressure, and Levitra are easily recognized and green, and discuss the blood circulation in the walls of the practice shows that a wound. Full text: a1smile.com

Here is the presentation:

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Also available on the Flint Journal’s editorial call to abandon Flint River as water source here.

Additional Sampling Confirms High Lead in Flint’s Water and Our 5-Minute Flushing Advice to Reduce Risk

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Dr. Edwards and Sid visited 4 homes that had tested high for lead in water last week with four goals:

We did confirm high lead. In 3 of 3 homes that we resampled where the plumbing was working normally, each tested with lead levels above 15 ppb (even when we collected and controlled the samples every step of the process). One home tested above 150 ppb. In the fourth home, the plumbing was blocked so badly the water would only come out at a trickle, and the lead levels were only 3 ppb. We intend to resample this home again when the water is flowing at normal flow rates. An interesting and logical hypothesis based on this result, is that sampling (or collecting water) at a low flow rate, might reduce the lead in water. This would only be true if a lot of the lead in water is particulate (see below).

Figure 1: We turned on the tap after the water sat for at least 6 hours, and then filled 1 liter bottles in sequence 1-8. At this house every bottle 1-8 was over the 15 ppb action level and the 10 ppb WHO standard (red line). We then collected a bottle after a total of 5 minutes flushing and after 10 minutes flushing. Five minutes flushing was needed to get below WHO standards at this house and 10 minutes flushing was slightly better.
Figure 1: We turned on the tap after the water sat for at least 6 hours, and then filled 1-liter bottles in sequence 1-8. At this house, every bottle (1-8) was over the 15 ppb action level and the 10 ppb WHO standard (red line). We then collected two bottles after 5 minutes and 10 minutes of total flushing respectively. Five minutes flushing was needed to get below WHO standards at this house, whereas 10 minutes flushing was slightly better.

Secondly, we did confirm that 5 minutes of flushing worked okay for reducing lead risks (see Figure 1). In every case tested so far, our advice to flush a minimum of 5 minutes did get the lead below World Health Organization (WHO) recommended maximum values for lead in water (10 ppb). The data also showed that 1 or 2 or even 3 minutes flushing was not good enough. While we only have data from 3 homes, it is somewhat reassuring that 5 minutes helps dramatically, even though the lead levels were still above 5 ppb, which we still think is too high for infants using formula or pregnant women. So overall we are sticking with our earlier advice, although we will keep you posted on what we find.

Third, for bottles 1, 3, 5, and 7 at each house, we passed some of the water through 0.45 um filters (i.e. filters with openings 0.45 micrometer in size). Tiny particles of lead would be removed by the filter, but soluble lead (i.e. lead dissolved in water like sugar and salt dissolve in water) should pass through. To our surprise, at most, only 15% of the lead went through the filter. This indicates that most of the lead in the water is particulate, which is what we found at Ms. Walters home as well. This also might explain why the fourth house in which water flowing at a trickle had low lead. Flow rate only has small impacts on soluble lead, and sampling at low flow should make soluble lead lower. But higher flow rates tend to increase release of particulate lead.

So, the expectation based on our prior work is that while low cost Brita pitcher filters would help reduce the lead in water risk, they would not be 90% effective. We confirmed this for two Brita pitcher filters that we sampled. On average, they were only removing 40-60% of the lead. That helps, but it is not good enough for us. Please note that other Brita NSF certified devices should be working fine, but Brita pitcher filters are not NSF certified.

Primary Author: Dr. Marc Edwards

Sampling and Data Graphs: Siddhartha Roy, Dr. Marc Edwards

Data Analysis: Dr. Jeffrey Parks