EarthTalk: Does oil drilling cause sinkholes or earthquakes? and is teeth whitening safe?
Dear EarthTalk: What, if anything, fills the empty space underground created by the extraction of billions of gallons of oil? Could oil drilling be one of the causes of increasing amounts of land settling and sinkholes in oil rich areas? Can it cause earthquakes?
– Linda Anderson, Sedona, AZ
The crude oil (and natural gas) we drill for the world over is, for the most part, stored in tiny pores within rock up to only about three miles deep in the Earth’s hugely dense crust. At such depths, the oil there is under fairly high pressure. When it is removed, other liquids — usually water — move in to take its place, equalizing the pressure in the process. Sometimes oil extractors pump water into one side of an oil field to push oil toward wells on the other side, and the water replaces the oil accordingly.
The U.S. Geological Survey cites several cases throughout the 20th century which they say demonstrate how accelerated withdrawal of oil and gas from some reservoirs can lower land elevation, cause minor earthquakes and activate faults around oil fields. Photo credit: Richard Masoner, courtesy Flickr
In cases where other liquids don’t move in, such as in the North Sea off The Netherlands, the porous rock layer that harbored the oil originally can collapse after extraction, causing slight amounts of land settling (known as “land subsidence”) in the rock layer surfaces above, but typically no more than a few tenths of an inch per year.
Here in the U.S., land subsidence induced by the large volume extraction of underground resources including oil and gas “is more common than most people realize,” according to the U.S. Geological Survey (USGS), a government agency which collects, monitors, analyzes and provides scientific understanding about natural resource conditions, issues and problems. Flat coastal plains and wetlands near sea level are most at risk from this potential side effect.
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No Standard for the Placebo?
University of California – San Diego: Much of medicine is based on what is considered the strongest possible evidence: The placebo-controlled trial. A paper published in the October 19 issue of Annals of Internal Medicine – entitled “What’s In Placebos: Who Knows?” calls into question this foundation upon which much of medicine rests, by showing that there is no standard behind the standard – no standard for the placebo.
The thinking behind relying on placebo-controlled trials is this: to be sure a treatment itself is effective, one needs to compare people whose only difference is whether or not they are taking the drug. Both groups should equally think they are on the drug – to protect against effects of factors like expectation. So study participants are allocated “randomly” to the drug or a “placebo” – a pill that might be mistaken for the active drug but is inert.
But, according to the paper’s author, Beatrice Golomb, MD, PhD, associate professor of medicine at the University of California, San Diego School of Medicine, this standard has a fundamental problem, “there isn’t anything actually known to be physiologically inert. On top of that, there are no regulations about what goes into placebos, and what is in them is often determined by the makers of the drug being studied, who have a vested interest in the outcome. And there has been no expectation that placebos’ composition be disclosed. At least then readers of the study might make up their own mind about whether the ingredients in the placebo might affect the interpretation of the study.”
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Soy intake associated with lower recurrence of breast cancer in hormone-sensitive cancers
Canadian Medical Association Journal: Post-menopausal breast cancer patients with hormone-sensitive cancers who consumed high amounts of soy isoflavones had a lower risk of recurrence, found a research study published in CMAJ (Canadian Medical Association Journal – pdf) .
Soy isoflavones are similar to estrogen in chemical structure and may stimulate or inhibit estrogen-like action in tissues. Consumption of soy isoflavones, found in soybeans and soy products, has increased in recent years and there are concerns about the effect of soy consumption on women with estrogen and progesterone receptor positive breast cancer as tumor growth is dependent on estrogen.
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Vitamin B12 may reduce risk of Alzheimer’s disease
American Academy of Neurology: A new study shows that vitamin B12 may protect against Alzheimer’s disease, adding more evidence to the scientific debate about whether the vitamin is effective in reducing the risk of memory loss. The research will be published in the October 19, 2010, issue of Neurology®, the medical journal of the American Academy of Neurology.
“Our findings show the need for further research on the role of vitamin B12 as a marker for identifying people who are at increased risk of Alzheimer’s disease,” said study author Babak Hooshmand, MD, MSc, with Karolinska Institutet in Stockholm, Sweden. “Low levels of vitamin B12 are surprisingly common in the elderly. However, the few studies that have investigated the usefulness of vitamin B12 supplements to reduce the risk of memory loss have had mixed results.”
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Scientists suggest that cancer is purely man-made
Cancer is a modern, man-made disease caused by environmental factors such as pollution and diet, a study by University of Manchester scientists has strongly suggested.
PhysOrg.com: The study of remains and literature from ancient Egypt and Greece and earlier periods – carried out at Manchester’s KNH Centre for Biomedical Egyptology and published in Nature Reviews Cancer – includes the first histological diagnosis of cancer in an Egyptian mummy.
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Right foods aid memory and protect against disease
Lund University: For the first time researchers have found out what effect multiple, rather than just single, foods with anti-inflammatory effects have on healthy individuals.
The results of a diet study show that bad cholesterol was reduced by 33 per cent, blood lipids by 14 per cent, blood pressure by 8 per cent and a risk marker for blood clots by 26 per cent. A marker of inflammation in the body was also greatly reduced, while memory and cognitive function were improved.
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Study confirms: Whatever doesn’t kill us can make us stronger
Psychologists say we fare better after some life difficulties, than if we’ve had many or none at all
University at Buffalo: We’ve all heard the adage that whatever doesn’t kill us makes us stronger, but until now the preponderance of scientific evidence has offered little support for it.
However, a new national multi-year longitudinal study of the effects of adverse life events on mental health has found that adverse experiences do, in fact, appear to foster subsequent adaptability and resilience, with resulting advantages for mental health and well being.
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