on how the substance got into the body and in what quantity. German biochemist Dr. Marc-Michael Blum, who previously headed the OPCW laboratory, as well as the team investigating the poisoning of Sergei and Yulia Skripal, confirmed that when Navalny was poisoned by Novichok, those around him could not have suffered: according to Blum, this indicated either that the level of exposure to the substance or the degree of its ingress into Navalny's body was too low, or that no one around had come into contact with the epicenter of the poison. Blum praised the work of the laboratory of the Institute of Pharmacology and Toxicology of the Bundeswehr, which was the first to confirm the poisoning of Navalny by Novichok (Blum had worked there in 2006–2010). Blum categorically denied that the OPCW laboratories could have engaged in conspiracies and falsified the results of chemical analysis by anyone's political will. After the OPCW published its own report, Blum stated: "five laboratories ... certified by the OPCW ... did the same tests and came to the same result," that "Navalny was poisoned with a chemical agent." Blum confirmed that "use of chemical weapons" and "violation of the Chemical Weapons Convention" is not determined by the presence of a substance on the List of Schedule 1 substances (CWC): "in the end, there is no need for the substance to be on the list — the point is how it will be used." Boris Zhuikov, Doctor of Chemistry and Head of the Laboratory of the Institute for Nuclear Research of the Russian Academy of Sciences, explained that although Novichok can break down in the body relatively quickly (for example, in a couple of days), when decomposed, it leaves behind specific compounds containing fragments of Novichok molecules, with which it is possible not only to confirm a poisoning by Novichok, but also to establish which substance from this group was used. The Russian team stated that it did not find Novichok itself in its analyses of Navalny's samples, while the German laboratory found traces of Novichok's presence. Zhuikov explained that these statements do not necessarily contradict each other: "the substance itself is really no longer there, but the interaction products remained." Modern methods of analysis (primarily mass spectrometry in combination with chromatography) make it possible to detect such chemical byproducts with very high sensitivity (for example, easily detecting the presence of 1 mg of