Both the great Truths and the great Falsehoods of the twentieth century lie hidden in the arcane, widely inaccessible, and seemingly mundane domain of the radiation sciences

Monday, October 18, 2010

The Trial of the Cult of Nuclearists: EXHIBIT F continued


What follows is the continuation, in serial form, of a central chapter from my book A Primer in the Art of Deception: The Cult of Nuclearists, Uranium Weapons and Fraudulent Science.



EXHIBIT F continued:



In addition to the research conducted on infant leukemia induced by Chernobyl fallout, the ECRR has identified a second body of research that unequivocally confirms that major shortcomings exist in the ICRP model of radiation effects. Again as a result of radiation vented from Chernobyl, data has been collected that proves elevated rates of minisatellite DNA mutations among exposed groups. Minisatellites are identical short segments of DNA that repeat over and over again in a long array along a chromosome. These stretches of DNA do not code for the formation of any protein. What distinguishes these minisatellites is that they acquire spontaneous repeats through mutation at a known rate, which is 1,000 times higher than normal protein-coding genes. Dr. Yuri Dubrova, currently at the University of Leicester, first realized that these stretches of DNA could be used to detect radiation-induced genetic mutations by showing that their known rate of mutation had increased subsequent to exposure. By this technique, only small population samples would be required to detect a trend in the rate of radiation-induced mutations. The accuracy of this methodology was first confirmed by Dr. Dubrova in mice. He then set out to investigate radiation-induced mutation in the human germ line — sperm and egg cells — among groups receiving exposure to Chernobyl fallout. That such mutation occurred in fruit flies and mice which was then passed on to their offspring had been known since the 1920s. That the same phenomenon occurred in humans had yet to be proven. Human germ line DNA is well protected against acquiring mutations. Most damage is immediately repaired. Irreparable damage frequently initiates cell death so that mutations are prevented from being passed on to the next generation. As a consequence, germ line mutations are rarely detected. The children of the atomic bomb survivors in Hiroshima and Nagasaki provided no evidence of any significant difference in mutation rates when compared to control groups.


Dr. Dubrova and his colleagues [1,2] studied the rate of minisatellite mutations in families that had lived in the heavily polluted rural areas of the Mogilev district of Belarus after the Chernobyl meltdown. They found the frequency of mutations being passed on by males to their descendants was nearly twice as high in the exposed families compared to the control group families. Among those exposed, the mutation rate was significantly greater in families with a higher parental dose. This finding was consistent with the hypothesis that radiation had induced the germ line mutations. It was the first conclusive proof that radiation produced inheritable germ line mutations in humans. The significance of this line of research was further confirmed by research in Belarus on the germ line mutations induced by Chernobyl fallout in barn swallows [3]. Minisatellite mutations were observed and were accompanied by observable phenotypic alterations in plumage patterns as well as reduced rates of survival.


In 2002, Dr. Dubrova published further research [4] in the journal Science concerning genetic mutation in populations exposed to fallout from atmospheric weapon testing. Between 1949 and 1956, the Soviet Union had detonated a series of aboveground atomic tests at the Semipalatinsk nuclear facility in Kazakhstan. The local population suffered significant radiation exposure throughout this period. The team led by Dr. Dubrova analyzed blood samples from three generations of about 40 families dwelling in the rural district of Beskaragai. They discovered a nearly 80-percent increase in the mutation rate in individuals directly exposed to the fallout in comparison with a suitable non-irradiated control population. The children of affected individuals evidenced a 50-percent increase in minisatellite mutations when compared to the children of non-irradiated parents. After the 1950s, when the practice of atmospheric weapon testing came to an end, the rates of mutation steadily declined.


Minisatellite DNA testing has also been performed on the children of Chernobyl “liquidators” i.e., those people who participated in post-accident cleanup operations. When the offspring of liquidators born after the accident were compared to their siblings born prior to the accident, a sevenfold increase in genetic damage was observed [5]. As reported by the ECRR, “for the loci measured, this finding defined an error of between 700-fold and 2,000-fold in the ICRP model for heritable genetic damage.” The ECRR made this further observation:


It is remarkable that studies of the children of those exposed to external radiation at Hiroshima show little or no such effect, suggesting a fundamental difference in mechanism between the exposures [Satoh and Kodaira 1996.] The most likely difference is that it was the internal exposure to the Chernobyl liquidators that caused the effects” [6].




Bibliography



[1] Dubrova Y.E., et al. Human Minisatellite Mutation Rate after the Chernobyl Accident. Nature. 1996; 380:683-686 .


[2] Dubrova Y.E., Nesterov V.N., Jeffreys A.J., et al. Further Evidence for Elevated Human Minisatellite Mutation Rate in Belarus Eight Years After the Chernobyl Accident. Mutation Research. 1997; 381:267-278.


[3] Ellegren H., Lindgren G., Primmer C.R., Moeller A.P. Fitness Loss and Germline Mutations in Barn Swallows Breeding in Chernobyl. Nature. 1997; 389(9):583-584.


[4] Dubrova Y. E., et al. Nuclear Weapons Tests and Human Germline Mutation Rate. Science. 2002; 295:1037.


[5] Weinberg H.S., Korol A.B., Kiezhner V.M., Avavivi A., Fahima T., Nevo E., Shapiro S., Rennert G., Piatak O., Stepanova E.I., Skarskaja E. Very High Mutation Rate in Offspring of Chernobyl Accident Liquidators. Proceedings of the Royal Society London. 2001; D, 266:1001-1005.


[6] European Committee on Radiation Risk (ECRR). Recommendations of the European Committee on Radiation Risk: the Health Effects of Ionising Radiation Exposure at Low Doses for Radiation Protection Purposes. Regulators' Edition. Brussels; 2003. www.euradcom.org.