Tag Archives: Colorado

Arsenic in Drinking Water can be Associated with just about any Adverse Health Effect

Arsenic is a favorite contaminant to be studied by epidemiologists. Looks as though there are more limitations to this study design than acknowledged by the authors. 

James KA, Byers T, Hokanson JE, Meliker JR, Zerbe GO, Marshall JA. 2015.  Association between lifetime exposure to inorganic arsenic in drinking water and coronary heart disease in Colorado residents. Environmental Health Perspective 123:128–134; http://dx.doi. org/10.1289/ehp.1307839

Background: Chronic diseases, including coronary heart disease (CHD), have been associated with ingestion of drinking water with high levels of inorganic arsenic (> 1,000 μg/L). However, associations have been inconclusive in populations with lower levels (< 100 μg/L) of inorganic arsenic exposure.

Objectives: We conducted a case-cohort study based on individual estimates of lifetime arsenic exposure to examine the relationship between chronic low-level arsenic exposure and risk of CHD.

Methods: This study included 555 participants with 96 CHD events diagnosed between 1984 and 1998 for which individual lifetime arsenic exposure estimates were determined using data from structured interviews and secondary data sources to determine lifetime residence, which was linked to a geospatial model of arsenic concentrations in drinking water. These lifetime arsenic exposure estimates were correlated with historically collected urinary arsenic concentrations. A Cox proportional-hazards model with time-dependent CHD risk factors was used to assess the association between time-weighted average (TWA) lifetime exposure to low-level inorganic arsenic in drinking water and incident CHD.

Results: We estimated a positive association between low-level inorganic arsenic exposure and CHD risk [hazard ratio (HR): = 1.38, 95% CI: 1.09, 1.78] per 15 μg/L while adjusting for age, sex, first-degree family history of CHD, and serum low-density lipoprotein levels. The risk of CHD increased monotonically with increasing TWAs for inorganic arsenic exposure in water relative to < 20 μg/L (HR = 1.2, 95% CI: 0.6, 2.2 for 20–30 μg/L; HR = 2.2; 95% CI: 1.2, 4.0 for 30–45 μg/L; and HR = 3, 95% CI: 1.1, 9.1 for 45–88 μg/L).

Conclusions: Lifetime exposure to low-level inorganic arsenic in drinking water was associated with increased risk for CHD in this population.

Boulder Temperature Adjustments Arbitrary

“Measured minimum temperatures in Boulder, CO show a strong cooling trend over the last 60 years, but NOAA massively tampers with the data to turn it into a warming trend.” click here

Tertiary-Butyl Alcohol in Hydrocarbon-Rich Groundwater Basin, Colorado

Quast KW, Levine AD, Kester JE, Fordham CL. Forensic analysis of tertiary-butyl alcohol (TBA) detections in a hydrocarbon-rich groundwater basin. Environmental monitoring and assessment. 2016 Apr;188(4):208. doi: 10.1007/s10661-016-5193-7.

Tertiary-butyl alcohol (TBA), a high-production volume (HPV) chemical, was sporadically detected in groundwater and coalbed methane (CBM) wells in southeastern Colorado’s hydrocarbon-rich Raton Basin. TBA concentrations in shallow water wells averaged 75.1 μg/L, while detections in deeper CBM wells averaged 14.4 μg/L. The detection of TBA prompted a forensic investigation to try to identify potential sources. Historic and recent data were reviewed to determine if there was a discernable pattern of TBA occurrence. Supplemental samples from domestic water wells, monitor wells, CBM wells, surface waters, and hydraulic fracturing (HF) fluids were analyzed for TBA in conjunction with methyl tertiary-butyl ether (MTBE) and ethyl tertiary-butyl ether (ETBE), proxies for evidence of contamination from reformulated gasoline or associated oxygenates. Exploratory microbiological sampling was conducted to determine if methanotrophic organisms co-occurred with TBA in individual wells. Meaningful comparisons of historic TBA data were limited due to widely varying reporting limits. Mapping of TBA occurrence did not reveal any spatial patterns or physical associations with CBM operations or contamination plumes. Additionally, TBA was not detected in HF fluids or surface water samples. Given the widespread use of TBA in industrial and consumer products, including water well completion materials, it is likely that multiple diffuse sources exist. Exploratory data on stable isotopes, dissolved gases, and microbial profiling provide preliminary evidence that methanotrophic activity may be producing TBA from naturally occurring isobutane. Reported TBA concentrations were significantly below a conservative risk-based drinking water screening level of 8000 μg/L derived from animal toxicity data.

Lack of Evidence for Drinking Water Well Contamination from Hydraulic Fracturing

Li H, Son JH, Carlson KH. Concurrence of aqueous and gas phase contamination of groundwater in the Wattenberg oil and gas field of northern Colorado. Water research 2015 Oct 21;88:458-466. doi: 10.1016/j.watres.2015.10.031.

The potential impact of rapid development of unconventional oil and natural gas resources using hydraulic fracturing and horizontal drilling on regional groundwater quality has received significant attention. Major concerns are methane or oil/gas related hydrocarbon (such as TPHs, BTEX including benzene, toluene, ethybenzene and xylene) leaks into the aquifer due to the failure of casing and/or stray gas migration. Previously, we investigated the relationship between oil and gas activity and dissolved methane concentration in a drinking water aquifer with the major finding being the presence of thermogenic methane contamination, but did not find detectable concentrations of TPHs or BTEX. To understand if aqueous and gas phases from the producing formation were transported concurrently to drinking water aquifers without the presence of oil/gas related hydrocarbons, the ionic composition of three water groups was studied: (1) uncontaminated deep confined aquifer, (2) suspected contaminated groundwater – deep confined aquifer containing thermogenic methane, and (3) produced water from nearby oil and gas wells that would represent aqueous phase contaminants. On the basis of quantitative and spatial analysis, we identified that the “thermogenic methane contaminated” groundwater did not have similarities to produced water in terms of ionic character (e.g. Cl/TDS ratio), but rather to the “uncontaminated” groundwater. The analysis indicates that aquifer wells with demonstrated gas phase contamination have not been contacted by an aqueous phase from oil and gas operations according to the methodology we use in this study and the current groundwater quality data from COGCC. However, the research does not prove conclusively that this the case. The results may provide insight on contamination mechanisms since improperly sealed well casing may result in stray gas but not aqueous phase transport.

Colorado Arsenic Study Looks Impressive, but is it True?

Back in the days when drinking water epidemiology studies were useful, this type of study would not have gotten off the ground because exposure is not directly measured. Why is this important? Because if enough assumptions are made using computer models an association can be found just about anywhere between anything. And that looks to be what has happened here. These authors in many respects have simply ended up assuming their way to the desired conclusion without realizing it. Having said that, it is reasonable to expect arsenic exposure to have a role in CHD and the Alamosa area is known for high ground water arsenic concentrations. (The town of Alamosa now has treatment for arsenic removal.) At issue is whether there is an effect at concentrations below 50 ug/L (the old limit) or even 10 ug/L (the new standard). As with the Alan Smith internal cancer study in 1991, advocates will grab on to this study to make alarming political statements.

As a side note, whether funding was provided for the study (and if so from who) really has no role in defining the credibility of the study. The authors state they were not financially supported. But this is irrelevant. Of most importance are the assumptions behind the analysis many of which are unstated. And of course, if they are employed someone pays them for their work. A lot of work went into this study and some aspects are useful. The weakness is in the underlying data, analysis and interpretation. Data and analysis are not neutral. The presuppositions and assumptions of the researchers define the outcome.

Finally, EHP is government funded and run publication that generally publishes papers from a particular point of view regardless of the strength of the study.

James KA, Byers T, Hokanson JE, Meliker JR, Zerbe GO, Marshall JA. Association between Lifetime Exposure to Inorganic Arsenic in Drinking Water and Coronary Heart Disease in Colorado Residents. Environ Health Perspect. 2014 Oct 28.

BACKGROUND: Chronic diseases, including coronary heart disease, have been associated with ingestion of drinking water with high levels of inorganic arsenic (over 1000 μg/L). However, associations have been inconclusive in populations with lower levels (<100 μg/L) of inorganic arsenic exposure.

OBJECTIVES: We conducted a case-cohort study based on individual estimates of lifetime arsenic exposure to examine the relationship between chronic low-level arsenic exposure and risk of CHD.

METHODS: This study included 555 participants with 96 CHD events diagnosed between 1984 and 1998 for which individual lifetime arsenic exposure estimates were determined using data from structured interviews and secondary data sources to determine lifetime residence which was linked to a, geospatial model of arsenic concentrations in drinking water, which were correlated with historically collected urinary arsenic concentrations. A Cox proportional hazards model with time-dependent CHD risk factors was used to assess the association between lifetime exposure to low-level inorganic arsenic in drinking water and incident CHD.

RESULTS: We estimated a positive association between low-level inorganic arsenic exposure and CHD risk (Hazard Ratio (HR): =1.38, 95%=1.09 1.78 per 15 μg/L) while adjusting for age, gender, first-degree family history of CHD, and serum low density lipoprotein levels. The risk of CHD increased monotonically with increasing TWAs for inorganic arsenic exposure in water relative to < 20 μg/L (HR=1.2; 95% CI: 0.6, 2.2 for 20-30 μg/L, HR=2.2; 95% CI: 1.2, 4.0 for 30-45 μg/L, and HR=3; 95% CI: 1.1, 9.1 for 45-88 μg/L).

CONCLUSIONS: Lifetime exposure to low-level inorganic arsenic in drinking water was associated with increased risk for CHD in this population.

The study is here.

Untruths (aka lies) spread by the Union of Concerned Scientists on fracking

“Local officials in Erie, Colo., are pushing back hard against a national environmental group for misrepresenting the outcome of a failed “ban fracking” campaign in their town. The officials say the Massachusetts-based group has “ignored or misstated” the facts, including a number of scientific analyses posted on the town’s website, and they are demanding to know: “Why did you ignore this information?” ” click here

Colo. Gov. Hickenlooper admits – gun laws do not prevent shootings

“During a December 15 appearance on Face the Nation, Colorado Governor John Hickenlooper (D-CO) said the gun control laws that have cost at least two state senators their political careers did not make “a difference at all” in the Arapahoe High School shooting.” click here