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Re: Chelyabinsk



Following the excellent recommendations by:



> From: Yarmoshenko IV <ivylist@ECKO.URAN.RU>

> Date: Fri, 7 Sep 2001 10:14:33 +0600

> Subject: Re: Chelyabinsk



Note that the principal source of the collected data is UNSCEAR 2000.



A recent paper (2000), including Dr. Degteva, is:

Radiation and Environmental Biophysics, Volume 39 Issue 4 (2000) pp 219-225



Mortality in the offspring of individuals living along the radioactively

contaminated Techa River: a descriptive analysis



M. M. Kossenko (1), Y. Ostroumova (1), A. Akleyev (1), N. Startsev (1), M.

Degteva (1), F. Granath (2), P. Hall (2)



Received: 18 August 2000 / Accepted: 22 September 2000



Abstract:  From 1949 onwards, radioactive waste was released into the Techa

River in the southern Urals and the population living along the river was

exposed to ionising radiation. Relocation of these people did not start

until several years later, causing many individuals to be exposed to

substantial doses from internal and external radiation. The identification

and follow-up of the exposed individuals started more than 40 years ago and

is still continuing. The Techa River offspring cohort (TROC) that has

recently been established, comprises 10,459 children born to at least one

parent living along the Techa River during the period 1950-1992. Of these

children, 3,897 were born during the period of highest release, i.e. between

1950 and 1956 and might thus have been exposed in utero. A total of 1,103

individuals have since died mainly due to infectious and respiratory

diseases, injury and poisoning. Only 25 cases were identified as having died

of a malignant condition. The radioactive contamination of the Techa River

in the southern Urals gives a unique possibility to study the adverse

effects of protracted exposure to ionising radiation in a large

well-described cohort. The Techa River offspring cohort will make it

possible to study the effects on those exposed in utero or early in life and

the follow-up of the cohort in the future is, therefore, of great

importance. Comparisons with other cohorts of humans exposed early in life,

will increase our knowledge in this field of research.



Refs on the doses/effects to the region are:



24. Krestinina LY, Kossenko MM, Kostyuchenko VA (1991)

Lethal developmental defects in descendents of a population

residing in the area of a radioactive trace. Med Radiol 36:

30­32

25. Kossenko MM, Izhevsky PV, Degteva MO, Akleev AV,

Vyushkova OV (1994) Pregnancy outcome and early health

status of children born to the Techa river population. Sci Total

Environ 142: 91­100

26. Kossenko MM, Gudkova NV (1996) Leukemia in the progeny

of the exposed parents. (in Russian) Med Radiol Radiat Safety

41: 23­28

27. Akleyev AV, Lyubchansky ER (1994) Environmental and

medical effects of nuclear weapon production on the Southern

Urals. Sci Total Environ 142: 1­8

28. Degteva MO, Vorobiova MI, Kozheurov VP, Tolstykh EI,

Anspaugh IR, Napier BA (2000) Dose reconstruction system

for the exposed population living along the Techa River.

Health Phys 78: 542­554



A summary of previous studies from the paper is:



"Fatal congenital malformations have previously been

studied in 33,500 children of parents exposed as a result

of the so-called Kyshtym accident [24]. The average gonadal

dose was 5 mSv and the non-exposed comparison

group included 21,357 individuals. No increase in severe

developmental defects relating to ionising radiation was

seen.

     Liquid radioactive waste was discharged into the

Techa River from the Mayak radiochemical facility in

the period 1949­1956. Pregnancy outcome and health

status of the children born to parents living along the

Techa River has previously been studied [25] and no effect

of ionising radiation could be seen on birth rates,

number of abortions (medical or spontaneous), stillbirths,

congenital malformations, or mortality when children

of exposed and unexposed parents were compared.

A study of leukaemia incidence among offspring of parents

exposed in the Techa River villages has previously

been conducted [26]. During the period 1950­1998, 13

cases of hematopoetic malignancies were registered in

the offspring. The incidence of haematological malignancies

in the offspring did not exceed that of the comparison

group and no leukaemia incidence related to gonadal

doses of the parents was found.

     The aim of the present paper was to describe the newly

established Techa River offspring cohort (TROC), its

structure and potentials, as well as the present status of the

ongoing studies on mortality related to gonadal, in utero

and childhood exposure to ionising radiation. Causes of

death in the TROC have not yet been studied in detail."



In the preliminary childhood mortality data in the paper, there are no

obvious significant effects, but the oldest of this group is only 50 years

old so the group will need to be followed into the cancer-prone years to see

if cancer is increased.



Note the following statement:



"The external

exposure has been found to be substantially lower

because previous calculations were based on the assumption

that all residents in a village received the same dose

as those living closest to the riverbank. Thus, the distance

from the river had not been taken into consideration;

furthermore, the old calculations overestimated the

time spent on the riverbanks."



And, in ref to Alice Stewart's and other studies:

"In utero exposure to ionising radiation,

as a consequence of x-ray exposure during pregnancy,

has been more thoroughly studied but the data

are controversial. Case-control studies have consistently

shown a small increased risk of childhood leukaemia

following a history of prenatal radiation, but most cohort

studies have not supported this association. Early

case-control studies were criticised for selection bias,

since no adjustment was made for potential confounders

such as concomitant diseases in the mother and/or

the fetus, and recall bias, as exposure information was

based on interviews with the parents of affected children.

      Little is known about the carcinogenic effect of gonadal

and in utero exposure to ionising radiation after

protracted exposure. The TROC will provide the opportunity

to the scientific community to study carcinogenesis

in a cohort with a fairly reliable follow-up (comparably

few leaving the area under surveillance) and carefully

calculated dosimetry. The population is slowly moving

into the period of life when cancer is most frequently

diagnosed, i.e. the oldest member of the cohort will be

50 years old in 2000, and follow-up is thus needed for

many years to come."



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