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The Chernobyl nuclear power plant accident on April 26, 1986 was the largest in the history of the peaceful use of nuclear energy. Of the 237 individuals initially suspected to have been significantly exposed to radiation during or in the immediate aftermath of the accident, the diagnosis of acute radiation sickness (ARS) could be confirmed in 134 cases on the basis of clinical symptoms. Of these, 54 patients suffered from cutaneous radiation syndrome (CRS) to varying degrees. Among the 28 patients who died from the immediate consequences of accidental radiation exposure, acute hemopoietic syndrome due to bone marrow failure was the primary cause of death only in a minority. In 16 of these 28 deaths, the primary cause was attributed to CRS. This report describes the characteristic cutaneous sequelae as well as associated clinical symptoms and diseases of 15 survivors of the Chernobyl accident with severe localized exposure who were systematically followed up by our groups between 1991 and 2000. All patients presented with CRS of varying severity, showing xerosis, cutaneous telangiectasias and subungual splinter hemorrhages, hemangiomas and lymphangiomas, epidermal atrophy, disseminated keratoses, extensive dermal and subcutaneous fibrosis with partial ulcerations, and pigmentary changes including radiation lentigo. Surprisingly, no cutaneous malignancies have been detected so far in those areas that received large radiation exposures and that developed keratoses; however, two patients first presented in 1999 with basal cell carcinomas on the nape of the neck and the right lower eyelid, areas that received lower exposures. During the follow-up period, two patients were lost due to death from myelodysplastic syndrome in 1995 and acute myelogenous leukemia in 1998, respectively. Other radiation-induced diseases such as dry eye syndrome (3/15), radiation cataract (5/15), xerostomia (4/15) and increased FSH levels (7/15) indicating impaired fertility were also documented. This study, which analyzes 14 years in the clinical course of a cohort of patients with a unique exposure pattern, corroborates the requirement for long-term, if not life-long, follow-up not only in atomic bomb survivors, but also after predominantly local radiation exposure.

A follow-up of ten highly irradiated men, mostly reactor crew, from the Chernobyl accident is described. Their pre-accident medical conditions, and relevant medical status approximately 10-13y later are listed. A comparison is made between estimates, derived from several biological parameters, of their average whole-body penetrating radiation doses. First estimates were based on their presenting severity of prodromal sickness, early changes in blood cell counts, and dicentric chromosome aberrations in lymphocytes. In three cases ESR measurements on tooth enamel were also made. Retrospective dosimetry using FISH translocations was attempted 10-13 y later. This showed good agreement for those patients with the lower earlier dose estimates; up to about 3 Gy. For the others, extending up to about 12 Gy, the translocations indicated lower values, suggesting that in these cases translocations had somewhat declined. Repeated chromosomal examinations during the follow-up period showed an expected decline in dicentric frequencies. The pattern of decline was biphasic with a more rapid first phase, with a half-life of about 4 months followed by a slower decline with half-lives around 2-4 y. The rapid phase persisted for longer in those patients who had received the highest doses. 10-13 y later dicentric levels were still above normal background but well below the translocation frequencies.

No abstract

The daily topical application of two compounds, a cream containing 10% evening primrose oil (EPO) and Lioxasol (a compound used clinically to treat radiation burns), resulted in increased cell proliferative activity in the skin of female Large White pigs. The effect was most pronounced in the case of the EPO based cream, and was comparable in magnitude with that observed in a previous study on pig skin using orally administered EPO. There was an increase in the size of the rete pegs in the epidermis by 6 weeks after the start of application of the EPO cream. However, this did not translate into an increase in the total thickness of the viable epidermis (excluding the stratum corneum) due to a reduction in the density of rete pegs, from 2 weeks after treatment. Lioxasol had no overall effect on the size of the rete pegs. The labelling index (LI) of cells in the basal layer of the epidermis of pigs receiving a daily topical application of EPO increased progressively with time from the start of application. The LI was maximal (17.9 +/- 2.4%) at the end of the observation period (8 weeks) at which time it was a factor of approximately 2 higher than in the basal layer prior to treatment. A considerably less marked increase in the LI of the basal layer was seen after the application of Lioxasol. The overall increase was approximately 20%, relative to the LI in the untreated epidermis. Labelled cell nuclei were also counted in the papillary dermis. After the application of the EPO cream, no significant increase in the number of labelled cells was observed until week 8, at which time values were approximately twice those in untreated skin. In Lioxasol treated skin the effect on the numbers of labelled cells in the papillary dermis was more immediate, with a approximately 60% increase at 2 weeks. This enhanced level of labelling was maintained until the end of the observation period of 10 weeks. Studies on the cell kinetics of the skin using the alcohol component of the Lioxasol preparation suggested that alcohol rather than Lioxasol was the most significant ingredient. It was concluded that the EPO cream merited further evaluation as a potential modulator of skin response to ionizing radiation.