Obama Administration Preparing Reckless Amnesty Plan

“The White House is considering two central requirements in deciding which of the nation’s 11 million illegal immigrants would gain protections through an expected executive action: a minimum length of time in the U.S., and a person’s family ties to others in the country, said people familiar with the administration’s thinking.” click here

CDC Finally Admits Ebola Potentially Transmitted Through Sneezing

“Ebola is a lot easier to catch than health officials have admitted — and can be contracted by contact with a doorknob contaminated by a sneeze from an infected person an hour or more before, experts told The Post Tuesday.” click here

Evaluation of Fluoride, Herbal Toothpastes Against Streptococcus mutans

Randall J, Seow W, Walsh L. Antibacterial activity of fluoride compounds and herbal toothpastes on Streptococcus mutans: An in vitro study. Australian dental journal. 2014 Oct 27. doi: 10.1111/adj.12247.

BACKGROUND: Streptococcus mutans is an important bacterial species implicated in dental caries. This laboratory study compared the antimicrobial activity of a number of fluoride-containing and herbal dentifrices and their components against S. mutans.

METHODS: An agar diffusion method was used with Mueller-Hinton agar. Wells were filled with either 10 commercial fluoride or 6 herbal dentifrices, or with solutions of various fluoride compounds, sodium lauryl sulphate, sodium benzoate, chlorhexidine digluconate or triclosan. Diameters of zones of bacterial growth inhibition surrounding the wells were measured using a micrometer.

RESULTS: Significant differences were found for growth inhibition between the 10 fluoridated dentifrices (P<0.0001), with Colgate Total having the greatest effect. There was not a direct correlation with fluoride type or fluoride concentration. The antibacterial activities of the 6 herbal toothpastes varied, with Herbal Fresh being the strongest. Sodium lauryl sulphate showed strong antimicrobial activity against S. mutans at the levels used in dentifrices.

CONCLUSIONS: Antimicrobial activity of commercial dentifrices against S. mutans may be exerted by components other than fluoride. Ingredients such as triclosan and sodium lauryl sulphate have larger antimicrobial effects than fluorides in this model.

Click here for full paper (fee).

 

Radon in Beijing City Drinking Water

Wu YY, Ma YZ, Cui HX, Liu JX, Sun YR, Shang B, Su X Radon concentrations in drinking water in beijing city, china and contribution to radiation dose. International journal of environmental research and public health. 2014 Oct 27;11(11):11121-31. doi: 10.3390/ijerph111111121.

222Rn concentrations in drinking water samples from Beijing City, China, were determined based on a simple method for the continuous monitoring of radon using a radon-in-air monitor coupled to an air-water exchanger. A total of 89 water samples were sampled and analyzed for their 222Rn content. The observed radon levels ranged from detection limit up to 49 Bq/L. The calculated arithmetic and geometric means of radon concentrations in all measured samples were equal to 5.87 and 4.63 Bq/L, respectively. The average annual effective dose from ingestion of radon in drinking water was 2.78 μSv, and that of inhalation of water-borne radon was 28.5 μSv. It is concluded that it is not the ingestion of waterborne radon, but inhalation of the radon escaping from water that is a substantial part of the radiological hazard. Radon in water is a big concern for public health, especially for consumers who directly use well water with very high radon concentration.

Click here for paper (Open Access).

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.

Effect of Rising CO2 Levels on Eutrophic Surface Waters

A lot of effort was expended in performing this study with some interesting results. Keep in mind that a laboratory chemostat is an artificial environment. The natural environment is much more complex and may not behave according to the model in the same way as in the laboratory.  How the model fairs when applied more broadly to different types of natural waters should be evaluated.  As noted in the paper’s introduction, mineralization of organic carbon can cause CO2 supersaturation in a lake. Aquatic CO2 levels exceeding 10,000 ppm have been noted.

Jolanda M. H. Verspagen, Dedmer B. Van de Waal Jan F. Finke, Petra M. Visser, Ellen Van Donk, Jef Huisman. Verspagen JMH, Van de Waal DB, Finke JF, Visser PM, Van Donk E, et al. (2014) Rising CO2 Levels Will Intensify Phytoplankton Blooms in Eutrophic and Hypertrophic Lakes. PLoS ONE 9(8): e104325. doi:10.1371/journal.pone.0104325

Harmful algal blooms threaten the water quality of many eutrophic and hypertrophic lakes and cause severe ecological and economic damage worldwide. Dense blooms often deplete the dissolved CO2 concentration and raise pH. Yet, quantitative prediction of the feedbacks between phytoplankton growth, CO2 drawdown and the inorganic carbon chemistry of aquatic ecosystems has received surprisingly little attention. Here, we develop a mathematical model to predict dynamic changes in dissolved inorganic carbon (DIC), pH and alkalinity during phytoplankton bloom development. We tested the model in chemostat experiments with the freshwater cyanobacterium Microcystis aeruginosa at different CO2 levels. The experiments showed that dense blooms sequestered large amounts of atmospheric CO2, not only by their own biomass production but also by inducing a high pH and alkalinity that enhanced the capacity for DIC storage in the system. We used the model to explore how phytoplankton blooms of eutrophic waters will respond to rising CO2 levels. The model predicts that (1) dense phytoplankton blooms in low- and moderately alkaline waters can deplete the dissolved CO2 concentration to limiting levels and raise the pH over a relatively wide range of atmospheric CO2 conditions, (2) rising atmospheric CO2 levels will enhance phytoplankton blooms in low- and moderately alkaline waters with high nutrient loads, and (3) above some threshold, rising atmospheric CO2 will alleviate phytoplankton blooms from carbon limitation, resulting in less intense CO2 depletion and a lesser increase in pH. Sensitivity analysis indicated that the model predictions were qualitatively robust. Quantitatively, the predictions were sensitive to variation in lake depth, DIC input and CO2 gas transfer across the air-water interface, but relatively robust to variation in the carbon uptake mechanisms of phytoplankton. In total, these findings warn that rising CO2 levels may result in a marked intensification of phytoplankton blooms in eutrophic and hypertrophic waters.

Click here for full paper (Open Access).

Ebola Survives on Surfaces, Certain Strains Last for Weeks

A pretty good overview of the Ebola situation is here.

1414427694150_wps_3_Figure_3_jpg ebola survival

The left-hand charts plot survival rates of Zaire strain of Ebola (Zebov) and Lake Victoria marburgvirus (Marv) on glass (a) and plastic (b) at 4° (39°F) over 14 days. The right-hand charts reveal the survival rate under the same conditions over 50 days. Both viruses survived for 26 days, and Ebola was extracted after 50 days.    Source: Mail Online

Of course, one must ask why the Obama Administration handled it the way they did, starting off as Ebola deniers.