Part 6: The polonium trail – events in October and November 2006
Part 6: The polonium trail – events in October and November 2006
Chapter 1: Introduction
¶6.1 The police officers investigating Alexander Litvinenko's death painstakingly pieced
together the last weeks of his life. In doing so, they employed standard techniques such as interviewing Mr Litvinenko's friends and associates, investigating the movements of persons of interest, interrogating telephone records and seizing and viewing closed circuit television (CCTV) footage. The material obtained in this way has all been made available to me, and a large amount of it has been put in evidence.
¶6.2 One task that the police undertook was to compile a schedule of all telephone calls
made to and from individuals considered to be of relevance to this Inquiry during the period June to November 2006. I adduced this (lengthy) document into evidence, and will refer to it hereafter as 'the telephone schedule'.1
¶6.3 But in addition to such conventional sources of evidence, it became apparent that there was a highly unusual, in fact unprecedented, line of inquiry to be followed.
¶6.4 Forensic scientists were sent to conduct tests for alpha radiation at a series of locations
across London and, subsequently, beyond. The results demonstrated widespread radioactive contamination at locations that had been linked to Mr Lugovoy, Mr Kovtun and Mr Litvinenko in a period of a little over two weeks from mid October until the onset of Mr Litvinenko's fatal illness in early November.
¶6.5 In this Part of the Report, I propose to set out the narrative of events during that period.
110In doing so I shall refer not only to the extensive witness and documentary evidence that has been adduced, but also to the body of evidence arising from the testing for radioactive contamination – the evidence that has become popularly known as 'the polonium trail'.1 Marina Litvinenko 3/19-20; INQ017734 (page 2 paragraph 6) Goldfarb 26/123; Emmerson 1/147 INQ022399 In fact, there are two versions of the telephone schedule in evidence: the original schedule, INQ017809; and a subsequent slightly more detailed schedule covering only the dates 31 October 2006 to 3 November 2006, INQ020044
¶The Litvinenko Inquiry
Chapter 2: Introduction to the scientific evidence
¶6.6 I have referred above to the discovery of traces of polonium 210 in Mr Litvinenko's
urine shortly before he died, and the subsequent tests that were carried out on his body after his death, which indicated that he had died as a result of ingesting polonium some weeks before his death.
¶6.7 This Part of the Report is concerned with a different series of tests – tests that were
conducted not on Mr Litvinenko's body, but at a series of locations. Some were associated with Mr Litvinenko, others with Mr Lugovoy and Mr Kovtun. Some of the most significant results were found at locations associated with all three.
¶6.8 The monitoring of the scenes for contamination was a highly complex task. As various
sites were identified as having been contaminated in the days and weeks following Mr Litvinenko's death – hotel rooms, restaurants, aircraft, offices – the police were faced with competing requirements, on the one hand to clean up the sites in the interests of public safety, but, on the other hand, to obtain forensic evidence of the contamination for the purposes of their investigation. Detective Inspector (DI) Mascall said that the task that faced the police and the forensic scientists in this respect was unprecedented, certainly in the United Kingdom (UK). In the course of his evidence he explained the system of sequential testing that was adopted involving the police, scientists from the Atomic Weapons Establishment (AWE) and scientists from the Health Protection Agency (HPA).2
¶6.9 Witness A1 was one of the principal scientific experts who gave evidence to the
Inquiry. She is an expert in nuclear physics who spent 34 years working for the AWE in Aldermaston; she now works for another nuclear establishment in the UK. Of particular relevance to the Inquiry, A1 recently held the post of Manager of Nuclear Forensics at AWE. As will become apparent, A1 provided detailed and lengthy written evidence for the Inquiry (including the 'contamination schedule' to which I refer below), and also attended to give oral evidence on two occasions. I am most grateful for the assistance that A1 has provided to the Inquiry.3
¶6.10 A1 gave evidence as to the means by which the testing was undertaken. Tests in the
field were conducted using alpha detectors. This equipment had the advantage of being portable and was capable of detecting the presence and, where present, the approximate strength of alpha radiation. Where significant findings were made, swabs were taken with filter papers, which were then sent to the laboratory to be analysed using more sophisticated spectrometry equipment.4
¶6.11 The first and most basic question was whether the alpha radiation found at the various
scenes had indeed been caused by contamination with polonium 210, as opposed to any other radionuclide (for example, uranium 232, which has an alpha output indistinguishable from that of polonium 210). A1 stated that in the light of laboratory tests using both alpha and gamma spectrometry, she was absolutely confident in the conclusion that the alpha radiation discovered at the multiple scenes had been caused by polonium 210.5
¶Mascall 9/68-70 3
¶A fuller description of A1's CV is at 2/101-104 4
¶A1 2/114 5
¶A1 2/114-115
111¶Part 6 | Chapters 1 to 8 | The polonium trail – events in October and November 2006
¶6.12 Beyond that finding, the principal questions that arose were, first, the level of each of the findings and, second, the inferences that could be drawn from the results.
¶6.13 In order to provide an evidential basis for assessing these questions, a schedule was
compiled containing all the results of all the testing that had been conducted at the scenes that were relevant to the investigation. I admitted this document – which was referred to during the course of the hearings as "the contamination schedule" into evidence.6 It is an extremely long document, running to over 260 pages. In common with almost all the documents that I have admitted into evidence, the contamination schedule is available on the Inquiry website. The schedule contains very much more detail regarding the testing results than is included in this Report; those wishing to analyse this part of the evidence in more depth will find it an invaluable tool.
¶6.14 A1 gave oral evidence twice: on Day 2 and Day 20. On the second occasion she was
asked to express an opinion as to inferences that could be drawn from each of the readings, in particular those in the higher range. Broadly speaking, A1 divided the readings into two categories.
¶6.15 A1 categorised a small number of the very highest readings as indicating a site
of primary contamination, a term that she defined for these purposes as, "the contamination that has come from the main source of material". In practical terms, A1 agreed that the term referred to the first point of contamination – for example, where a solution containing polonium 210 had been directly applied to a surface.7
¶6.16 The other category, referred to during the hearings as secondary or transferred
contamination, comprised sites where the contamination had been caused not as a result of exposure to the main source of material – i.e. polonium 210 – but rather as a result of the transfer of contamination, either directly or indirectly from a site of primary contamination. A1 explained that there was: "a range of ways in which the contamination from the original source can be transferred so that could potentially be on somebody's hand, by somebody's foot, et cetera".8 She also stated that:
"… the transfer of polonium from primary contamination areas to other areas is dependent upon the physical and chemical properties of polonium and the surface of the materials on which it is deposited. The amount of contamination transferred is dependent upon the amount of original activity present on each successive surface to which it is transferred."9 Marina Litvinenko 3/3-6 HMG000078 INQ019146 (page 22 paragraph 68) Cotlick 25/76-81 March 2015
¶6.17 One important feature of the forensic testing in this case was that it was conducted
some weeks after the dates on which the contamination appears to have taken place. As will be seen from the contamination schedule, most of the testing was undertaken during December 2006. On the assumption that the contamination occurred in late October and early November 2006, in each case there was a gap of several weeks between the date of contamination and the date of testing.
¶6.18 A1 explained that this delay caused the readings to be lower than they would have
been at the time of contamination. First, in each case the level of alpha radiation being emitted will have decreased during the intervening period as a result of the rapid radioactive decay that is characteristic of polonium. Second, in some cases
¶INQ017934 7
¶A1 2/149-150 8
¶A1 2/150 9
¶A1 2/149
112¶The Litvinenko Inquiry
environmental conditions such as the cleaning of surfaces or (in the case of sinks, drains, etc) the effect of running water will have further reduced the readings, a point to which I shall return.
¶6.19 Finally for the purpose of this introduction, it should be noted that different considerations flow from positive and negative findings of contamination.
¶6.20 In the instances where contamination was detected in relation to a place or an object,
there is a positive finding that calls for explanation. The existence of that positive finding is not affected by the fact that, for the reasons discussed above, the original level of contamination is likely to have been higher than that found.
¶6.21 The position is somewhat different where a location was tested without any positive
findings of contamination being made. As we shall see, there were a number of these 'negative findings' during the course of the investigation. They included buses on which Mr Lugovoy and Mr Kovtun travelled, and also other buses on which Mr Litvinenko had travelled.
¶6.22 One explanation for such findings is that the person of interest was not contaminated
at the time that he travelled on the bus. This is the counterpart to the conclusion drawn in the case of positive findings of contamination, i.e. that the person of interest was contaminated at the relevant time.
¶6.23 In the case of negative findings, however, there are other possibilities. One is that
the person of interest was contaminated at the time, but that he did not contaminate the bus, perhaps because the journey was too short, and/or he did not sit down or touch anything. Another possibility is that the person of interest was contaminated at the time of travel and did contaminate the bus, but the contamination was no longer present at the time of testing, as a result of decay and/or environmental factors such as cleaning.
¶6.24 I therefore consider that the negative findings must be approached with caution. Given
113the different possible explanations for these test results, and without any means of determining which is the accurate explanation in any particular case, these results must generally be treated as being neutral. There is one possible exception to this general approach, to which I shall return below.
¶Part 6 | Chapters 1 to 8 | The polonium trail – events in October and November 2006