TORCH report

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In 2006, German Green Member of the European Parliament Rebecca Harms, commissioned two British scientists to write an alternate report (TORCH, The Other Report on Chernobyl) in response to the United Nations report on Chernobyl. The TORCH Report stated that:

"In terms of their surface areas, Belarus (22% of its land area) and Austria (13%) were most affected by higher levels of contamination. Other countries were seriously affected; for example, more than 5% of Ukraine, Finland and Sweden were contaminated to high levels (> 40,000 Bq/m2 caesium-137). More than 80% of Moldova, the European part of Turkey, Slovenia, Switzerland, Austria and the Slovak Republic were contaminated to lower levels (> 4000 Bq/m2 caesium-137). And 44% of Germany and 34% of the UK were similarly affected." (See map of radioactive distribution of Caesium-137 in Europe) [1]

This report was reviewed by Chris Busby (of the The Low Level Radiation Campaign ) who commented that the TORCH report on chernobyl was "a theoretical review of a small part of the evidence accrued in twenty years since the Chernobyl disaster" and he also comments on his web site that it "It reveals consistent bias in that it ignores or under-reports crucial developments in radio-biology".

Contents

[edit] Cesium

The IAEA/WHO and UNSCEAR considered areas with exposure greater than 40 kBq/m2; the TORCH report also included areas contaminated with more than 4000 Bq/m2 of Cs-137. The TORCH report might be alarming but 4 kBq/m2 of Cs-137 only gives an external gamma dose of 56 μSv per year (which is close to nothing, a 1 in 356000 chance of death due to cancer). The internal dose will depend greatly on the diet of the person and the degree to which simple countermeasures such as Prussian blue are used in animal farming. For details of the properties of Cs-137 see the IAEA report on the Goiânia accident[2].

To sum these properties up

  • The dose rate due to external irradiation from uniform contamination of the ground by 137Cs is 1.6 x 10-12 Sv hr-1 Bq-1 m3.
  • The internal dose for ingestion is 1.2 x 10-8 Sv Bq-1
  • The internal dose for inhalation is 8.7 x 10-9 Sv Bq-1

Note that 4 kBq/m2 is the minimum level which is considered by the TORCH report. The TORCH report does not consider contamination under that threshold, but contamination levels between 4 and 40 kBq/m2, which are ignored by the Forum's report. The lower limit for 137Cs which the authors of the TORCH report used is exceptionally low, all soil contains radioactive isotopes which are natural. The most important of these is 40K, for example a randomly chosen soil (From the Trinity test site) has about 1000 Bq Kg-1 (P.P. Parekh, T.M. Semkow, M.A. Torres, D.K. Haines, J.M. Cooper, P.M. Rosenberg and M.E. Kitto, Jorunal of Environmental Radioactivity, 2006, 85, 103-120) which results in a square meter of soil having about 100 KBq in the top 10 cm. It is important to note that radioactivity is present everywhere (and has been since the formation of the earth).

According to the IAEA, one kilogram of soil typically contains the following amounts of the following three natural radioisotopes 370 Bq 40K (typical range 100-700 Bq), 25 Bq 226Ra (typical range 10-50 Bq), 25 Bq 238U (typical range 10-50 Bq) and 25 Bq 232Th (typical range 7-50 Bq).[2].


[edit] Iodine and thyroid effects

The TORCH 2006 report "estimated that more than half the iodine-131 from Chernobyl [which increases the risk of thyroid cancer] was deposited outside the former Soviet Union. Possible increases in thyroid cancer have been reported in the Czech Republic and the UK, but more research is needed to evaluate thyroid cancer incidences in Western Europe". It predicted about 30,000 to 60,000 excess cancer deaths and warned that predictions of excess cancer deaths strongly depend on the risk factor used; and predicted excess cases of thyroid cancer range between 18,000 and 66,000 in Belarus alone depending on the risk projection model [3]

[edit] Other cancers

Furthermore it pointed out that many diseases have latencies such that it is very difficult to generate accurate estimates as early as 2006, stating that "most solid cancers have long periods between exposure and appearance of between 20 and 60 years. Now, 20 years after the accident, an average 40% increased incidence in solid cancer has been observed in Belarus with the most pronounced increase in the most contaminated regions." It also quoted the 2005 Forum's report, which documented preliminary evidence of an increase in the incidence of pre-menopausal breast cancer among women exposed at ages lower than 45 years.

[edit] Health effects other than cancer

The TORCH report also stated that "two non-cancer effects, cataract induction and cardiovascular diseases, are well documented with clear evidence of a Chernobyl connection." Quoting the report, Nature wrote that: "it is well known that radiation can damage genes and chromosomes"; "the relationship between genetic changes and the development of future disease is complex and the relevance of such damage to future risk is often unclear. On the other hand, a number of recent studies have examined genetic damage in those exposed to radiation from the Chernobyl accident. Studies in Belarus have suggested a twofold increase in the germline minisatellite mutation rate". [4] [5]ò

[edit] References

  1. ^
  2. ^ Generic Procedures for Assessment and Response during a Radiological Emergency, IAEA TECDOC Series number 1162, published in 2000 [1]
  3. ^ TORCH report executive summary, op.cit., p.4
  4. ^
  5. ^ Concerning human minisatellite mutation rate after the Chernobyl accident, the Nature April 2006 article also quotes "Human minisatellite mutation rate after the Chernobyl accident", Nature n° 380, April 25, 1996. Retrieved on April 21, 2006.