Allen JM, Cuthbertson AA, Liberatore HK, Kimura SY, Mantha A, Edwards MA, Richardson SD. Showering in Flint, MI: Is there a DBP problem? J Environ Sci (China). 2017 Aug;58:271-284. doi: 10.1016/j.jes.2017.06.009.
Lead contamination in the City of Flint, MI has been well documented over the past two years, with lead levels above the EPA Action Level until summer 2016. This resulted from an ill-fated decision to switch from Detroit water (Lake Huron) with corrosion control, to Flint River water without corrosion control. Although lead levels are now closer to normal, reports of skin rashes have sparked questions surrounding tap water in some Flint homes. This study investigated the presence of contaminants, including disinfection by-products (DBPs), in the hot tap water used for showering in the homes of residents in Flint. Extensive quantitative analysis of 61 regulated and priority unregulated DBPs was conducted in Flint hot and cold tap water, along with the analysis of 50 volatile organic compounds and a nontarget comprehensive, broadscreen analysis, to identify a possible source for the reported skin rashes. For comparison, chlorinated hot and cold waters from three other cities were also sampled, including Detroit, which also uses Lake Huron as its source water. Results showed that hot water samples generally contained elevated levels of regulated and priority unregulated DBPs compared to cold water samples, but trihalomethanes were still within regulatory limits. Overall, hot shower water from Flint was similar to waters sampled from the three other cities and did not have unusually high levels of DBPs or other organic chemicals that could be responsible for the skin rashes observed by residents. It is possible that an inorganic chemical or microbial contaminant may be responsible.
Sampling for lead in drinking is easier said than done. There are scientific and technical issues that complicate sampling and interpretation of testing results. It is important to understand that the purpose of sampling for lead under the USEPA lead rule is not exposure assessment. The primary goal is to confirm whether or not the water system is practicing optimal corrosion control. Seems to me that we are at a critical juncture in regulating lead in drinking water and some innovative thinking is needed to develop and move forward with a regulatory approach that will be effective in reducing lead exposure.
Goovaerts P. Monitoring the aftermath of Flint drinking water contamination crisis: Another case of sampling bias? Sci Total Environ. 2017 Mar 2. pii: S0048-9697(17)30440-0. doi: 10.1016/j.scitotenv.2017.02.183.
The delay in reporting high levels of lead in Flint drinking water, following the city’s switch to the Flint River as its water supply, was partially caused by the biased selection of sampling sites away from the lead pipe network. Since Flint returned to its pre-crisis source of drinking water, the State has been monitoring water lead levels (WLL) at selected “sentinel” sites. In a first phase that lasted two months, 739 residences were sampled, most of them bi-weekly, to determine the general health of the distribution system and to track temporal changes in lead levels. During the same period, water samples were also collected through a voluntary program whereby concerned citizens received free testing kits and conducted sampling on their own. State officials relied on the former data to demonstrate the steady improvement in water quality. A recent analysis of data collected by voluntary sampling revealed, however, an opposite trend with lead levels increasing over time. This paper looks at potential sampling bias to explain such differences. Although houses with higher WLL were more likely to be sampled repeatedly, voluntary sampling turned out to reproduce fairly well the main characteristics (i.e. presence of lead service lines (LSL), construction year) of Flint housing stock. State-controlled sampling was less representative; e.g., sentinel sites with LSL were mostly built between 1935 and 1950 in lower poverty areas, which might hamper our ability to disentangle the effects of LSL and premise plumbing (lead fixtures and pipes present within old houses) on WLL. Also, there was no sentinel site with LSL in two of the most impoverished wards, including where the percentage of children with elevated blood lead levels tripled following the switch in water supply. Correcting for sampling bias narrowed the gap between sampling programs, yet overall temporal trends are still opposite.
Pieper KJ, Tang M, Edwards MA. Flint Water Crisis Caused By Interrupted Corrosion Control: Investigating “Ground Zero” Home. Environmental science & technology. 2017 Feb 1. doi: 10.1021/acs.est.6b04034.
Flint, Michigan switched to the Flint River as a temporary drinking water source without implementing corrosion control in April 2014. Ten months later, water samples collected from a Flint residence revealed progressively rising water lead levels (104, 397, and 707 μg/L) coinciding with increasing water discoloration. An intensive follow-up monitoring event at this home investigated patterns of lead release by flow rate-all water samples contained lead above 15 μg/L and several exceeded hazardous waste levels (>5000 μg/L). Forensic evaluation of exhumed service line pipes compared to water contamination “fingerprint” analysis of trace elements, revealed that the immediate cause of the high water lead levels was the destabilization of lead-bearing corrosion rust layers that accumulated over decades on a galvanized iron pipe downstream of a lead pipe. After analysis of blood lead data revealed spiking lead in blood of Flint children in September 2015, a state of emergency was declared and public health interventions (distribution of filters and bottled water) likely averted an even worse exposure event due to rising water lead levels.
Goovaerts P. The drinking water contamination crisis in Flint: Modeling temporal trends of lead level since returning to Detroit water system. The Science of the total environment. 2016 Oct 5. pii: S0048-9697(16)32137-4. doi: 10.1016/j.scitotenv.2016.09.207.
Since Flint returned to its pre-crisis source of drinking water close to 25,000 water samples have been collected and tested for lead and copper in >10,000 residences. This paper presents the first analysis and time trend modeling of lead data, providing new insights about the impact of this intervention. The analysis started with geocoding all water lead levels (WLL) measured during an 11-month period following the return to the Detroit water supply. Each data was allocated to the corresponding tax parcel unit and linked to secondary datasets, such as the composition of service lines, year built, or census tract poverty level. Only data collected on residential parcels within the City limits were used in the analysis. One key feature of Flint data is their collection through two different sampling initiatives: (i) voluntary or homeowner-driven sampling whereby concerned citizens decided to acquire a testing kit and conduct sampling on their own (non-sentinel sites), and (ii) State-controlled sampling where data were collected bi-weekly at selected sites after training of residents by technical teams (sentinel sites). Temporal trends modeled from these two datasets were found to be statistically different with fewer sentinel data exceeding WLL thresholds ranging from 10 to 50μg/L. Even after adjusting for housing characteristics the odds ratio (OR) of measuring WLL above 15μg/L at non-sentinel sites is significantly >1 (OR=1.480) and it increases with the threshold (OR=2.055 for 50μg/L). Joinpoint regression showed that the city-wide percentage of WLL data above 15μg/L displayed four successive trends since the return to Detroit Water System. Despite the recent improvement in water quality, the culprit for differences between sampling programs needs to be identified as it impacts exposure assessment and might influence whether there is compliance or not with the Lead and Copper Rule.
Posted in Lead
Tagged Lead, Michigan
Mona Hanna-Attisha, Jenny LaChance, Richard Casey Sadler, and Allison Champney Schnepp. Elevated Blood Lead Levels in Children Associated With the Flint Drinking Water Crisis: A Spatial Analysis of Risk and Public Health Response. American Journal of Public Health. 2016;106:283–290. doi:10.2105/AJPH.2015.303003
Objectives. We analyzed differences in pediatric elevated blood lead level incidence before and after Flint, Michigan, introduced a more corrosive water source into an aging water system without adequate corrosion control.
Methods. We reviewed blood lead levels for children younger than 5 years before (2013) and after (2015) water source change in Greater Flint, Michigan. We assessed the percentage of elevated blood lead levels in both time periods, and identified geographical locations through spatial analysis.
Results. Incidence of elevated blood lead levels increased from 2.4% to 4.9% (P < .05) after water source change, and neighborhoods with the highest water lead levels experienced a 6.6% increase. No significant change was seen outside the city. Geospatial analysis identified disadvantaged neighborhoods as having the greatest elevated blood lead level increases and informed response prioritization during the now-declared public health emergency.
Conclusions. The percentage of children with elevated blood lead levels increased after water source change, particularly in socioeconomically disadvantaged neighborhoods. Water is a growing source of childhood lead exposure because of aging infrastructure.
Posted in Lead
Tagged Lead, Michigan
This may be hard for some people to swallow. But history has shown that problems like the Flint water crisis are the outgrowth and fruit of Democrat party controlled government…..I wish it were not so, but we can no longer be deniers.
“Flint, like big brother Detroit down the way, has a long history of political dominance by the Democratic party. Its current mayor is a Democrat; so was her predecessor; the mayor before him, Don Williamson, was a career criminal (he did time for various scams some years back) and a Democrat who resigned under threat of recall; his immediate predecessor, Democrat James W. Rutherford, is a longtime politico and was elected to finish out the term of Woodrow Stanley, who was recalled because of the financial state in which he left the city.” click here
It has been very interesting taking a look into the history and issues surrounding fluoride addition to drinking water. It’s for the children, of course. That’s why children were used as guinea pigs when fluoride addition to drinking water was tested in Grand Rapids, Michigan in 1945. If it was really harmfull, they would be sure to be able to tell right away. Those public health people….right on it!
(Um…well, this could not be done today most likely…..and a lifetime exposure effect like cancer would not be known until these children die, even if it could be detected in a small population…..but it must be safe….by definition.)…..And if there is a problem, these school and government officials will have retired by the time a problem is found anyway….so all is well. Right!
Children giving saliva samples in Grand Rapids, MI. National Library of Medicine
Click here for one of the more interesting fluoride history articles.