UMass Experts Recruited To Address DBP Questions In The Aftermath Of The Flint Water Crisis

The ongoing water crisis in Flint, Michigan is a tragedy. The lead (Pb) issue is well documented, as are the health effects from ingesting lead. No safe blood Pb level in children has been identified, and exposure to elevated levels of Pb can cause intellectual impairment and other health issues.

More recently, concerns have arisen regarding disinfection byproducts (DBPs) in Flint drinking water. Unlike exposure to high levels of Pb, the risk from DBPs is a chronic exposure risk, not an acute poisoning risk. In general, consuming elevated levels of DBPs is thought to cause an increased risk of some cancers over a typical lifetime. For this reason, some representative DBPs are regulated by the Environmental Protection Agency (EPA) under the Clean Water Act.

DBPs are formed in the water distribution system through an oxidation reaction between chlorine and natural organic matter (NOM). This formation of DBPs is an unfortunate negative consequence of adding chlorine for water disinfection, which is very common in the United States and other countries. Water chlorination has been practiced for 112 years, starting in Jersey City.

It is difficult to overstate the importance of water chlorination–perhaps the most important public health breakthrough of modern civilization, leading to eradication of most waterborne disease. However, the chlorine required to inactivate pathogens also reacts with NOM to form halogenated (chlorine is a halogen) organic byproducts including total trihalomethanes (aka TTHMs) and Haloacetic Acids (HAAs). This reaction is well understood, and is known to be a function of NOM concentration and character, pH, chlorine dose, time, temperature and other factors. DBPs are always formed whenever chlorine is added to surface waters, but the concentration and type of DBPs vary somewhat from city to city.

TTHMs in Flint water were shown to be problematic in 2014, with violations noted in the Consumer Confidence Report (CCR) of that year. (A similar violation for HAAs occurred in Amherst, Massachusetts that same year). Recently, DBPs including TTHMs have drawn attention following the discovery of Pb and other issues in the Flint Water system, and the subsequent measurement of some DBPs by non-scientists. However, the methods used in this sampling were unorthodox, relying on proprietary sponges marketed by the group, to collect samples, and the results are not comparable to refined and standard scientific methods. There are proven, peer-reviewed and published methods for collecting and analyzing DBP samples. These methods were refined by researchers at UMass, and trustworthy data that is scientifically rigorous are needed during times of crisis.

The UMass team was recruited by Virginia Tech, to execute the advanced DBP sampling. The team (lead by Dr. David Reckhow) is bringing drinking water quality expertise, to quantify the extent of DBP formation in the drinking water currently delivered to Flint residents, following the switch back to the Detroit Water & Sewerage Department (DWSD). It should be noted that, before the switch to Flint River in 2014, DWSD water was far below regulatory limits for TTHMs and HAAs, and no changes to the system during the water crisis is expected to affect formation of DBPs in the Flint system.

Initial results from samples collected in May 2016 indicate that there is nothing exceptional about DBP levels in Flint. Additional rounds of sampling and analyses are now being conducted to gather more information. Beyond regulated TTHMs and HAAs, the UMass team is also conducting analysis for >60 unregulated byproducts to get a more complete picture of the drinking water quality.Results from analysis will be forthcoming.

Members of the UMass Flint DBP Team include:

Dr. Dave Reckhow (Team Lead)

Dr. Joe Goodwill (DBP sampling, THMs, Iodo-THMs and other volatiles)

Yanjun Jiang (Iodo-THMs and other volatiles)

Xuyen Mai (DBP sampling)

Xian “Max” Ma (DBP sampling, Haloacetamides)

Ran Zhao (Haloacetamides and HAAs)

Soon-Mi Kim (Haloacids)

Yun “Rosa” Yu (N-halo-haloacetamides)

Aarthi Mohan (Halobenzoquinones)

Pranav Mashankar (Aldehydes)

Sherrie Webb-Yagodzinski (Sampling preparation)

Select members from both UMass Amherst and Virginia Tech during a sampling trip in late-May
Select members from both UMass Amherst and Virginia Tech during a sampling trip in late-May

Primary Author: Dr. Joseph Goodwill

Acknowledgements: Drs. Dave Reckhow and Marc Edwards

Results of March 2016 Legionella Sampling Event in Smaller Buildings in Flint

In March 2016, we sampled tap water from 5 homes and 6 small businesses in Flint, with ALL testing culture-negative for Legionella.  We used a standard culture-method often used by hospitals to determine if there is a risk of Legionnaire’s Disease outbreak.  This is good news.  We will be following up with another sampling this summer when the weather is warmer and there is more of a tendency of Legionella bacteria to grow.

We are also examining the water samples we have collected more closely using DNA-based methods.  The DNA methods may help us detect lower levels of Legionella that we couldn’t see with culture and also identify different kinds of Legionella, but the trade-off is that we will not be able to tell the difference between live and dead bacteria.  That is why the culture method is considered the standard for determining risk of getting Legionnaires’ Disease from tap water.

Using the best available science, the sampling we performed in March 2016 showed that if any living Legionella were present, their levels were low the day of testing. There is always some risk of Legionnaire’s Disease from tap water, but our current results from March suggest the risk was not concerning at any of our sample sites in Flint.  We will remain vigilant in our tracking and testing of this potential problem in Flint homes.

Flint Trip #3: Quick Sampling Update

Dr. Otto Schwake, Min Tang, and Ni “Joyce” Zhu are in Flint sampling the water for opportunistic pathogens, iron and lead before the switch to Detroit water. We will post an update on what we find very soon. Meanwhile, here is a photograph Joyce took when sampling water inside a Flint Hospital. We hope this is the last time we find something like this in a hospital or home in Flint.

Tap Water in a Flint Hospital on Oct. 16 (Picture courtesy: Joyce Zhu)
Tap Water in Flint’s Hospital on Oct. 16 (Picture courtesy: Joyce Zhu)

Watch the news coverage regarding our visit on ABC12 here.

Our Flint Sampling Trip (Aug 17-19 2015)

Objective: In response to the possible public health problems and infrastructure degradation that is occuring in the City of Flint, we organized a field trip for extensive sampling to better assess water quality concerns. This trip was planned and executed immediately after we finished mailing out 300 lead sampling kits to Flint residents.

Personnel: Our entire team of undergraduate/graduate students and scientists contributed in the time period leading up to the trip. Dr. Marc Edwards, Rebekah Martin, Dr. David “Otto” Schwake, Colin Richards, and Min Tang were the team selected to drive to Flint from Blacksburg VA. Emily Garner spent over 80 hours preparing a comprehensive biological sampling kit to look for OPPPs and bacteria that cause corrosion, while Dr. Jeff Parks and Anurag Mantha led up efforts to equip the FLINTWATERSTUDY van as a mobile lab.

Day 1 (Aug 17 2015)

Our trip to Flint MI from Blacksburg VA took eleven hours after which we made our first stop at Mrs LeeAnne Walters’ house to pick up sample kits supplied by Genesee County Health Department for measuring Escherichia coli and Coliforms. E.coli and coliforms are common (fecal indicator) bacteria and our analyses showed no presence of these in the water. We also tested for chlorine residuals in her tap water and were introduced to her family.

Ms. LeeAnne Walters shows Dr. Edwards a used Granular Activated Carbon (GAC) filter that was full of rust seven days into use
Ms. Walters shows Dr. Edwards a used filter that was full of rust seven days into use

Day 2 (Aug 18 2015)

We spent about five hours sampling at 10 sites, most of which are used by the city for their distribution system monitoring. These included the Flint River, a McDonald’s franchisee next to the water treatment plant, and another eight distribution monitoring sites typically used by the city. We took 1.5 L samples for microbial analyses and 500 mL samples to analyze the water temperature, dissolved oxygen and chlorine residual. These samples were processed immediately in our mobile lab. The purpose of this approach was to gather data on water quality at different points along Flint’s distribution system, and to verify similar data that was being collected by the city on the same day.

We then shipped the biological samples overnight to our Virginia Tech labs in Blacksburg, and submitted the E. coli and coliform samples to the Health Department for analysis in the afternoon. We later had dinner with Flint residents and community leaders, and interviewed them about their experiences with Flint water (to be uploaded).

Day 3 (Aug 19 2015)

We divided ourselves into three groups to maximize sampling. The first group sampled four businesses still on Detroit water, the second sampled four homes that are on Flint water, and the final group sampled two homes where residents had reported health issues. Chlorine levels were also monitored for one place with Detroit water and another with Flint water. We stayed up late to sample what happened to the water at night. The Detroit water had consistent chlorine residual of about 0.5 mg/L whereas the Flint waters had no residuals at 3 am.

We wrapped up sampling around noon, said our goodbyes to Ms. Walters and her family, and set off for the long journey back home.


Figure 4. The sampling sites with Detroit water (A-D) and Flint water (101-104, 11, 13). The water from one resident had white precipitates which needs further investigation.
The sampling sites with Detroit water (A-D) and Flint water (101-104, 11, 13). The water from one resident had white precipitates which needs further investigation.

Primary Authors: Min Tang and Colin Richards

Acknowledgements: Siddhartha Roy, Dr. Marc Edwards