Daily Archives: September 24, 2014

Ten Ways to Tell the UN Climate Summit is Not About Climate

From Dr. Roy Spencer:

“Next Tuesday’s UN climate conference in NYC (called Climate Summit 2014) is for politicians, celebrities, and rent seekers. It’s not about climate science, nor Saving the Earth from “carbon emissions” of fossil fuels.” click here for his post.

Review of Drinking Water Arsenic Epidemiology Studies

This study represents a typical epidemiology review of arsenic that is published every so often. This review confirms prior reviews that found exposure misclassification below about 100 ug/L. This severely limits arsenic risk assessment at low concentrations. The problem of misclassification was known over 20 years ago and yet was ignored when the arsenic regulation was lowered to 10 ug/L from 50 u/L. Linear extrapolation of data is an assumption made by regulatory agencies, but does not represent the best peer-reviewed science.

Epidemiologic modeling is a lot like climate modeling in that very little is really known about the physical systems being modeled. Extrapolation to very low levels of arsenic based on detection, feasibility, or health goals is typical of regulatory approaches, but such estimates are theoretical constructs only and have no direct relationship to actual arsenic health effects that may or may not be occurring in the population. Politicians use drinking water contaminants like arsenic to their advantage year after year because intuitively nobody wants arsenic in their drinking water. Arsenic is a contaminant of choice to alarm the public.

Agencies assume a general linearized extrpolation model to reach low regulatory levels. This is common in arsenic risk assessment but is not scientifically justifiable because (1) evidence is emerging to improve our understanding of health effects at low levels, and (2) sufficient evidence exists to show that linear extrapolation at low arsenic concentrations is not accurate. Theoretical estimates using such extrapolation methods are used to claim estimate that “lives are saved” as a result of lower and lower regulatory standards for drinking water when in reality such estimates represent no such thing and typically offer no incremental health benefit at a high cost.

Arsenic in drinking water and urinary tract cancers: a systematic review of 30 years of epidemiological evidence. Saint-Jacques, Nathalie, Parker, Louise, Brown, Patrick, Dummer, Trevor J. B. Environmental Health: A Global Access Science Source. 2014, Vol. 13 Issue 1, p1-43.

Background: Arsenic in drinking water is a public health issue affecting hundreds of millions of people worldwide. This review summarizes 30 years of epidemiological studies on arsenic exposure in drinking water and the risk of bladder or kidney cancer, quantifying these risks using a meta-analytical framework.

Methods: Forty studies met the selection criteria. Seventeen provided point estimates of arsenic concentrations in drinking water and were used in a meta-analysis of bladder cancer incidence (7 studies) and mortality (10 studies) and kidney cancer mortality (2 studies). Risk estimates for incidence and mortality were analyzed separately using Generalized linear models. Predicted risks for bladder cancer incidence were estimated at 10, 50 and 150 ug/L arsenic in drinking water. Bootstrap randomizations were used to assess robustness of effect size.

Results: Twenty-eight studies observed an association between arsenic in drinking water and bladder cancer. Ten studies showed an association with kidney cancer, although of lower magnitude than that for bladder cancer. The meta-analyses showed the predicted risks for bladder cancer incidence were 2.7 [1.2-4.1]; 4.2 [2.1-6.3] and; 5.8 [2.9-8.7] for drinking water arsenic levels of 10, 50, and 150 μg/L, respectively. Bootstrapped randomizations confirmed this increased risk, but, lowering the effect size to 1.4 [0.35-4.0], 2.3 [0.59-6.4], and 3.1[0.80- 8.9]. The latter suggests that with exposures to 50 μg/L, there was an 83% probability for elevated incidence of bladder cancer; and a 74% probability for elevated mortality. For both bladder and kidney cancers, mortality rates at 150 ug/L were about 30% greater than those at 10 μg/L.

Conclusion: Arsenic in drinking water is associated with an increased risk of bladder and kidney cancers, although at lower levels (<150 μg/L), there is uncertainty due to the increased likelihood of exposure misclassification at the lower end of the exposure curve. Meta-analyses suggest exposure to 10 μg/L of arsenic in drinking water may double the risk of bladder cancer, or at the very least, increase it by about 40%. With the large number of people exposed to these arsenic concentrations worldwide the public health consequences of arsenic in drinking water are substantial.

Communal Fluoridation is an Issue That Will not go Away, Until Fluoride Addition Goes Away

“CORNWALL, Ontario – City council still can’t make up its mind on whether to add fluoride to our drinking water.” click here

There are many vested interests in the “public” health industry that keep pushing the need for communal fluoridation of drinking water. How do we know?

A scientific questions that are unresolved cannot be wall-papered over by political decisions for ever. Fluoridation of drinking water began as a political issue and it continues as one. Other agendas keep propping it up.

As an observer it looks clear to me that cities continuing communal fluoridation of drinking water, like the Cornwall, Ontario city council, will see this issue come back again and again. 

Gravity-Powered Chemical Dose Controller

Gravity-Powered Chemical Dose Controller for Sustainable, Municipal-Scale Drinking Water Treatment. Swetland, Karen A., Swetland, Karen A., Weber-Shirk, Monroe L., Lion, Leonard W., Journal of Environmental Engineering. Aug 2013, Vol. 139 Issue 8, p1023-1034.

Accurate chemical dosing in water treatment plants is imperative to ensure optimal efficiency of flocculation and disinfection. Design algorithms, calibration techniques, and standardized components are presented for a linear flow orifice meter (LFOM) and a linear chemical dose controller (LCDC). These coupled systems allow water treatment plant operators to easily and reliably set and maintain the desired doses of coagulant and disinfectant. The combined system adjusts the chemical flow rate automatically in response to changes in plant flow rate to maintain the target chemical dose. The LFOM maintains a linear relationship between height of water in the entrance tank and plant flow rate. A lever and float are used to create a direct relationship between the plant flow and chemical flow produced by the LCDC. A linear relationship between head loss and chemical flow in the LCDC is created by using the major head loss through a small diameter tube to control the chemical flow rate. Experimental tests are described that minimize minor losses and verify performance of the LCDC.

Groundwater Controversy at Pavillion, Wyoming Natural Gas Field

Stephens DB. Analysis of the Groundwater Monitoring Controversy at the Pavillion, Wyoming Natural Gas Field. Ground Water. 2014 Sep 17. doi: 10.1111/gwat.12272.

The U.S. Environmental Protection Agency (EPA) was contacted by citizens of Pavillion, Wyoming 6 years ago regarding taste and odor in their water wells in an area where hydraulic fracturing operations were occurring. EPA conducted a field investigation, including drilling two deep monitor wells, and concluded in a draft report that constituents associated with hydraulic fracturing had impacted the drinking water aquifer. Following extensive media coverage, pressure from state and other federal agencies, and extensive technical criticism from industry, EPA stated the draft report would not undergo peer review, that it would not rely on the conclusions, and that it had relinquished its lead role in the investigation to the State of Wyoming for further investigation without resolving the source of the taste and odor problem. Review of the events leading up to EPA’s decision suggests that much of the criticism could have been avoided through improved preproject planning with clear objectives. Such planning would have identified the high national significance and potential implications of the proposed work. Expanded stakeholder involvement and technical input could have eliminated some of the difficulties that plagued the investigation. However, collecting baseline groundwater quality data prior to initiating hydraulic fracturing likely would have been an effective way to evaluate potential impacts. The Pavillion groundwater investigation provides an excellent opportunity for improving field methods, report transparency, clarity of communication, and the peer review process in future investigations of the impacts of hydraulic fracturing on groundwater.

Global Carbon Budget: Nature Absorbs More CO2 Than Previously Estimated

Lot of authors on this work. Certainly does not appear that the “science is settled” by any means.

C. Le Quéré, R. Moriarty, R. M. Andrew, G. P. Peters, P. Ciais, P. Friedlingstein, S. D. Jones, S. Sitch, P. Tans, A. Arneth, T. A. Boden, L. Bopp, Y. Bozec, J. G. Canadell, F. Chevallier, C. E. Cosca, I. Harris, M. Hoppema, R. A. Houghton, J. I. House, A. Jain, T. Johannessen, E. Kato, R. F. Keeling, V. Kitidis, K. Klein Goldewijk, C. Koven, C. S. Landa, P. Landschützer, A. Lenton, I. D. Lima, G. Marland, J. T. Mathis, N. Metzl, Y. Nojiri, A. Olsen, T. Ono, W. Peters, B. Pfeil, B. Poulter, M. R. Raupach, P. Regnier, C. Rödenbeck, S. Saito, J. E. Salisbury, U. Schuster, J. Schwinger, R. Séférian, J. Segschneider, T. Steinhoff, B. D. Stocker, A. J. Sutton, T. Takahashi, B. Tilbrook, G. R. van der Werf, N. Viovy, Y.-P. Wang, R. Wanninkhof, A. Wiltshire, and N. Zeng. Global Carbon Budget 2014. Earth Syst. Sci. Data Discuss., 7, 521-610, 2014. doi:10.5194/essdd-7-521-2014

Accurate assessment of anthropogenic carbon dioxide (CO2) emissions and their redistribution among the atmosphere, ocean, and terrestrial biosphere is important to better understand the global carbon cycle, support the development of climate policies, and project future climate change. Here we describe datasets and a methodology to quantify all major components of the global carbon budget, including their uncertainties, based on the combination of a range of data, algorithms, statistics and model estimates and their interpretation by a broad scientific community. We discuss changes compared to previous estimates, consistency within and among components, alongside methodology and data limitations. CO2 emissions from fossil fuel combustion and cement production (EFF) are based on energy statistics and cement production data, respectively, while emissions from Land-Use Change (ELUC), mainly deforestation, are based on combined evidence from land-cover change data, fire activity associated with deforestation, and models. The global atmospheric CO2 concentration is measured directly and its rate of growth (GATM) is computed from the annual changes in concentration. The mean ocean CO2 sink (SOCEAN) is based on observations from the 1990s, while the annual anomalies and trends are estimated with ocean models. The variability in SOCEAN is evaluated with data products based on surveys of ocean COmeasurements. The global residual terrestrial CO2 sink (SLAND) is estimated by the difference of the other terms of the global carbon budget and compared to results of independent Dynamic Global Vegetation Models forced by observed climate, CO2 and land cover change (some including nitrogen-carbon interactions). We compare the variability and mean land and ocean fluxes to estimates from three atmospheric inverse methods for three broad latitude bands. All uncertainties are reported as ±1σ, reflecting the current capacity to characterise the annual estimates of each component of the global carbon budget. For the last decade available (2004–2013), EFF was 8.9 ± 0.4 GtC yr−1ELUC 0.9 ± 0.5 GtC yr−1GATM 4.3 ± 0.1 GtC yr−1SOCEAN 2.6 ± 0.5 GtC yr−1, and SLAND 2.9 ± 0.8 GtC yr−1. For year 2013 alone, EFF grew to 9.9 ± 0.5 GtC yr−1, 2.3% above 2012, contining the growth trend in these emissions. ELUC was 0.9 ± 0.5 GtC yr−1GATM was 5.4 ± 0.2 GtC yr−1SOCEAN was 2.9 ± 0.5 GtC yr−1 and SLAND was 2.5 ± 0.9 GtC yr−1GATM was high in 2013 reflecting a steady increase in EFF and smaller and opposite changes between SOCEAN and SLAND compared to the past decade (2004–2013). The global atmospheric CO2 concentration reached 395.31 ± 0.10 ppm averaged over 2013. We estimate that EFF will increase by 2.5% (1.3–3.5%) to 10.1 ± 0.6 GtC in 2014 (37.0 ± 2.2 GtCO2 yr−1), 65% above emissions in 1990, based on projections of World Gross Domestic Product and recent changes in the carbon intensity of the economy. From this projection of EFF and assumed constant ELUC for 2014, cumulative emissions of CO2 will reach about 545 ± 55 GtC (2000 ± 200 GtCO2) for 1870–2014, about 75% from EFFand 25% from ELUC. This paper documents changes in the methods and datasets used in this new carbon budget compared with previous publications of this living dataset (Le Quéré et al., 2013, 2014). All observations presented here can be downloaded from the Carbon Dioxide Information Analysis Center (doi:10.3334/CDIAC/GCP_2014).

Click here for full paper (Open Access).

 

Total water intake in the general population in Greece

Malisova, O., Bountziouka, V., Panagiotakos, D. Β., Zampelas, A., Kapsokefalou, M. Evaluation of seasonality on total water intake, water loss and water balance in the general population in Greece. Journal of Human Nutrition & Dietetics Jul2013 Supplement, Vol. 26, p90

Background: Water balance is achieved when water intake from solid and fluid foods and drinking water meets water losses, mainly in sweat, urine and faeces. Seasonality, particularly in Mediterranean countries that have a hot summer, may affect water loss and consequently water balance. Water balance has not been estimated before on a population level and the effect of seasonality has not been evaluated. The present study aimed to compare water balance, intake and loss in summer and winter in a sample of the general population in Greece.

Methods: The Water Balance Questionnaire ( WBQ) was used to evaluate water balance, estimating water intake and loss in summer ( n = 480) and in winter ( n = 412) on a stratified sample of the general population in Athens, Greece.

Results: In winter, mean (SD) water balance was −63 (1478) mL/day−1, mean (SD)water intake was 2892 (987) mL/day−1 and mean (quartile range) water loss was 2637 (1810-3922) mL/day−1. In summer, mean (SD) water balance was −58 (2150) mL/day−1, mean (SD) water intake was 3875 (1373) mL/day−1 and mean (quartile range) water loss was 3635 (2365-5258) mL/day−1. Water balance did not differ between summer and winter ( P = 0.96); however, the data distribution was different; in summer, approximately 8% more participants were falling in the low and high water balance categories. Differences in water intake from different sources were identified ( P < 0.05).

Conclusions: Water balance in summer and winter was not different. However, water intake and loss were approximately 40% higher in summer than in winter. More people were falling in the low and high water balance categories in summer when comparing the distribution on water balance in winter.