Dwindling helium supply

A professor at Washington University stated that helium is being depleted rapidly and the supply will be over with in the next eight years. Science & technology without helium is unthinkable. This article reviews the status of availability of helium world-wide and refers to the effort made indigenously to extract helium from Indian sources.

K.S.Parthasarathy





Science Tribune April 25, 2008


Dwindling helium supply
K.S. Parthasarathy
During the first week of this year, Prof Lee Sobotka at Washington University warned that helium is being depleted so rapidly in the world’s largest reserve, outside of Amarillo, Texas, that supplies are expected to be depleted there within the next eight years.
“Helium is nonrenewable and irreplaceable……… unlike hydrocarbon fuels (natural gas or oil) there are no biosynthetic ways to make an alternative to helium”, he clarified. It is a rare gas with many properties critical to several applications in high technology.
As helium does not become radioactive, it is a good coolant in nuclear reactors. Helium is the primary coolant in Pebble Bed Modular Reactors, innovative reactors of 165 MWe, being installed in South Africa. Helium is used as cover gas in the Indian pressurized heavy water reactors
Helium being non-flammable is a safer gas to fill balloons than hydrogen. It is an ideal inert gas shield for arc welding. In some countries, helium is cheaper than argon, another gas used for the same purpose. Helium is an excellent protective gas in growing silicon and germanium crystals.
It is the pressurizing agent of choice for liquid fuel rockets. Helium is a leak detection agent to identify extremely tiny leaks. Helium’s role in nuclear magnetic resonance and mass spectrometry is unique. A world without helium is unthinkable!
Helium may be of primordial or radiogenic origin. NASA’s Far Ultraviolet Spectroscopic Explorer (FUSE) satellite provided some evidence of helium gas left over from the big bang.
Uranium-238 and thorium-232 in the earth’s crust and mantle emit alpha particles which pick up two electrons and become radiogenic helium.
In the entire life span of the earth, only half of the uranium-238 atoms have decayed — yielding eight helium atoms in the process. Helium mixes with natural gas and will remain with it till it is extracted.
Helium that escapes into the atmosphere may be lost permanently. The atmospheric concentration of helium is very low at about 5.2 parts per million, too low to be harvested economically.
India currently imports virtually all its helium requirements of 10,000 normal cubic metres per month from the USA. Scientists at Variable Energy Cyclotron Centre (VECC), an institution under the Department of Atomic Energy, did some pioneering work in the field; they estimated that thermal spring gases at Bakereswar and Tantloi in West Bengal contain 1.4 and 1.26 vol % of helium respectively. Extracting and purifying helium from thermal springs and monazite sands are not commercially viable proposals.
The Ministry of Science and Technology had set up a special task force in early 2005 to identify India’s helium reserves.
Taking into account the strategic importance of helium, the Oil and Natural Gas Corporation set up a Rs 250 crore pilot plant at Kutralam in Tamil Nadu to produce 3,000 normal cubic metres per hour of helium from natural gas.
Poland, Russia, China. Algeria and Netherlands separate helium commercially from natural gas; helium is present in their oil fields at concentrations ranging from 0.18 and 0.9 vol percentage. In some US oilfields helium is present at 8 vol%.
The US government accumulated so far a reserve of 110 million standard cubic metres of this precious resource. In 1996, The US Congress decided to liquidate it by 2005 in such a way as to cause minimum market disruption.
A report from the National Academy of Sciences prepared on a direction from Congress assured that such a disposal of helium reserves will not have substantial adverse impact on US scientific, technical, biomedical, or national security interests.
The committee’s assurance on price stability through 2010 went wrong. The price of liquid helium is about $5 a litre; it rose more than 50% during the last year. The vagaries of the market place can hurt any dependent country
India’s decision to operate an indigenous plant to extract helium is strategically sound even if indigenous helium may turn out to be costlier than imported helium.

[K.S. Parthasarathy is former Secretary, Atomic Energy Regulatory Board]

Radiation epidemiological studies near nuclear facilities

This article criticizes authors who bypass the conventional peer review process and get articles published in news media.Only vigilant journalists can arrest this lamentable trend

K.S.Parthasarathy





April 17, 2008

Radiation epidemiological studies near nuclear facilities

There is evidence that the cancer rates in population groups exposed to high doses of radiation will be relatively high. But the evidence at low doses is controversial. A few specialists believe that low dose radiation is beneficial to man (the Hindu, September 29, 2005)!

The limitations

Many specialists want to know whether very low levels of radiation caused by permitted radioactive releases from nuclear power plants, uranium mines, mills etc can cause excess cancers in man or not.

They do not appreciate the limitations of epidemiology. They believe that they can get a deterministic answer to a purely probabilistic question! That too using a statistically weak study.

“…. there is often a tendency to carry out epidemiological studies concerning the induction of cancer in radiation workers and members of the public which are not supported by a statistically valid data base or whose result are misinterpreted or misused”. Drs Joan M. Davies and Hazel Inskip eminent epidemiologists wrote in the foreword to their book on the topic. (Davies and Inskip, 1986)

A paper titled “Meta- analysis of standardized incidence and mortality rates of childhood leukaemia in proximity to nuclear facilities by Baker and Hoel in the European Journal of Cancer Care (2007) illustrates the dilemma...

The authors reviewed studies from one hundred and thirty six sites in nine countries.

Although the analysis showed consistently elevated rates of leukaemia, the authors of such papers found that radiation dose due to environmental discharges from the facilities are too low to account for the excess cases.

In several studies, the leukaemia death rates remained unchanged before and after start up even in regions with elevated rates!

Low excess risk

A study at 62 sites in USA, revealed leukaemia death rates to be higher before start up of the nuclear facility when compared with those after start up. Some authors found excess leukaemia in regions where nuclear facilities were expected to come!

In these studies, no one brought out one point; excess risk, if any, is extremely low and zero risk cannot be rules out.
Recently, a section of the media published reports on a study by the Indian Doctors for Peace and Development (IDPD) claiming adverse health effects in villages within the radius of 2.5 km from the uranium mine in Jadugoda. Their conclusions remain unsubstantiated. (Unsubstantiated till published in a peer reviewed journal).
Bypassing peer review

The authors presented their “study” at a conference on “Nuclear Weapons: The Final Pandemic Preventing Proliferation and Achieving Abolition” during October 3-4, 2007 at London.

Peer review

They successfully circumvented the traditional scientific peer review and publication process by using the media. Only vigilant journalists can arrest this lamentable trend. The full paper which the organisers of the London Conference sent me showed how "cherry picking" can masquerade as epidemiology. At the very outset, the authors stated thus: “We assumed that specific health problems related to uranium mining was affecting the indigenous people disproportionately in the study villages compared to the reference villages”.

Questionnaire

Then they searched for evidence to support the assumption! “A structured questionnaire was developed…. and was introduced on the heads of families of each house hold by a team of investigators.

The investigators, 34 in number, were men and women from the vicinity of Jadugoda”. Their areas were carpet –bombed with weird stories on uranium hazards for the past few years!

Brazen admission

“ Responses to some of the variables in few of the interview schedules were not found to be satisfactory and such responses were not considered for data analysis” the authors brazenly admitted to “cherry picking” of the data. None of the medical committees of qualified specialists, which surveyed Jadugoda villages found any disease which could be related to radiation exposure. Based on media reports and other documents an advocate filed a Public Interest Litigation (No 188 of 1999) in the Supreme Court of India seeking judicial intervention to have the necessary steps taken to safeguard the health of the population.
“In view of the affidavit filed by respondent No 3-Chairman, Atomic Energy Commission, that adequate steps have been taken to check and control the radiation arising out of uranium waste, we do not find any merit in the petition.
It is accordingly dismissed” the Supreme Court stated in its judgment on April 15, 2004.
Specialists know that it is impossible to get conclusive evidence from studies with a weak data base. However, such studies will continue often as public relations exercises! No one wants to call a spade a spade!
K.S.PARTHASARATHY
ksparth@gmail.com
[K.S.Parthasarathy is former Secretary Atomic Energy Regulatory Board]

Atomic bomb survivors, cancers

Recently,researchers found that there was statistically significant increase in the adult cancers among those exposed in utero to the atomic bomb radiation at Hiroshima and Nagasaki. Over al, all studies conclude that ionizing radiation is a weak carcinogen
K.S.Parthasarathy



Date:03/04/2008 URL: http://www.thehindu.com/thehindu/seta/2008/04/03/stories/
2008040350041700.htm

Atomic bomb survivors, cancers

In utero exposure - cancer link was unknown

Study confirms that ionising radiation is a weak carcinogen

The study of atomic bomb survivors in Hiroshima and Nagasaki continues to provide very useful information on the effects of radiation on man.

Recently, Dr Dale Preston and co-workers examined the incidence of solid cancers in 2,452 atomic bomb survivors who got exposed to different radiation doses while they were in their mothers’ wombs.

They also evaluated the incidence of cancer in 15,388 persons who were younger than 6 years at the time of bombing. Both groups belonged to the age range of 12-55 for the period of 1955-1999.
Dose-related increases

They reported dose-related increases in the incidence of solid cancers in both groups (The Journal of the National Cancer Institute, March 19, 2008). Scientists knew that radiation exposure to foetus increases risks of childhood cancers and exposure in childhood is associated with increased risks of adult cancers. But until now they knew little about whether in utero radiation exposure leads to increased risks of adult cancers.
Heat rays

When U.S. aircraft dropped the bombs, Hiroshima and Nagasaki had an estimated population of 310,000 and 250,000 respectively.

About 90,000-140,000 people in Hiroshima and 60,000-80,000 in Nagasaki died immediately or within two to four months after bombing, resulting from collapse of houses caused by the blast and from heat rays and fires and radiation exposure.

In the 1950 Japanese national census, nearly 280,000 persons stated that they “had been exposed in the two cities” (The Hindu, September, 6, 2001)

One of the myths about the atomic bombing is that radiation released by atom bombs has been killing tens of thousands of persons in the two cities.

The deaths in areas of about a kilometre diameter are attributable to the effects of explosion and heat. Till 1990, RERF recorded 7,827 cancer deaths among the 86,572 persons who, the RERF included in its Life Span Study cohort.

Radiation exposure might have caused 421 excess cancer deaths (334 solid cancers + 87 leukaemias) among them (Radiation Research, 1996).

In 2007, researchers released the second general report on the incidence of solid cancers among the members of the Life Span Study. They based the analyses on 17,448 first primary cancers diagnosed from 1958 through 1998 among 105,427 cohort members with individual dose estimates, who were alive and not known to have cancer prior to 1958 (Radiation Research, July 2007). For all solid cancers as a group, scientists estimated that about 850 cancers were due to atomic bomb radiation exposure.

RERF, a bi-national Japan-U.S. scientific organization dedicated to studying the health effects of atomic bomb radiation took over the task of accumulating scientific results of significant versatility, quality, and quantity, through its studies of radiation effects on human health, with generous cooperation and support from A-bomb survivors and their family members (RERF release, March 5, 2008).

According to RERF, the majority of atomic bomb survivors are approaching their so-called cancer-prone years. “Cancer mortality associated with radiation exposure is expected to reach its peak during the next 10 years.

With great advances in genomic and other research, various powerful analytical techniques have become available.

Without a doubt, many important findings can only be produced at RERF by collecting, storing, and analyzing valuable clinical samples, such as cancer tissues, from the world’s largest prospective cohort for whom accurate and widely distributed dose information is available,” RERF noted.

“…These studies have important implications for risk assessment of low-dose medical and occupational exposures, since such exposures are expected to increase”, RERF argued.
Study’s confirmation

Overall, the study confirms that ionizing radiation is a carcinogen; also that it is a weak carcinogen (Scientists estimate that about 850 out of 17,448 solid cancers recorded during 1958 through 1998 may be due to radiation exposure).

The excess cancers may not have been noticed in the normal course.

K.S. PARTHASARATHY
FORMER SECRETARY, AERB

(ksparth@yahoo.co.uk)

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