"Titadyn", el libro de Iglesias, y la campaña de "El Mundo"

[Mangeclous]

Una curiosidad; repasando los artículos de "El mundo" que cita Erante en su análisis de la demanda de Manzano, encuentro la siguiente perla:

Los laboratorios de UEE, entre los más avanzados de Europa, son capaces de discernir hasta 50 partes por millón en una sustancia. Pues bien, nunca, hasta ahora, sus análisis han detectado contaminación con DNT

Los laboratorios europeos que nunca, nunca, han detectado contaminación por DNT -y son mejores que los nuestros, ¿o acaso nuestros laboratorios alcanzan una sensibilidad de 50 ppm?-. Será que eso de la contaminación es un cuento chino -inventado sin duda por el omnipresente Manzano-. El caso es que la contaminación de DNT detectada se encuentra por debajo de dicho nivel de sensibilidad.

Lo que es seguro es que en Europa nadie se preocupa por la contaminación de muestras.

The effectiveness of a number of the explosives contamination prevention controls that are adopted within the Forensic Explosives Laboratory (FEL) principal trace laboratory has been scrutinised. Within the trace laboratory, rigorous procedures for processing forensic swab samples for traces of organic explosives are routinely adopted by forensic scientists. In order to demonstrate the effectiveness of these procedures, and the principle of separating the sample from the laboratory and the forensic scientist, explosives-free swab samples and appropriate controls have been processed, in accordance with trace laboratory procedures, in several explosives contaminated environments. In all cases, no explosives were detected in the post-processing samples, demonstrating that the contamination prevention procedures are effective, robust and fit-for-purpose.

Y cuando digo nadie, es nadie.

(...)

All laboratories have contamination problems. These problems are unavoidable and largely insurmountable without significant investment in construction and maintenance of clean room facilities. The laboratory must have an active program designed to continuously monitor the many different types and sources of contamination. When contamination is found, active steps must be implemented to remove or minimize the contamination. In the absence of a vigorous contaminant minimization and monitoring program, laboratory results are always suspect.

Pero Isócrates ya nos trajo referencias acerca de la ausencia de literatura científica relacionada con la contaminación en laboratorios de análisis químicos.

The Forensic Explosives Laboratory (FEL) operates within the Defence Science and Technology Laboratory (DSTL) which is part of the UK Government Ministry of Defence (MOD). The FEL provides support and advice to the Home Office and UK police forces on matters relating to the criminal misuse of explosives. During 1989 the FEL established a weekly quality assurance testing regime in its explosives trace analysis laboratory. The purpose of the regime is to prevent the accumulation of explosives traces within the laboratory at levels that could, if other precautions failed, result in the contamination of samples and controls. Designated areas within the laboratory are swabbed using cotton wool swabs moistened with ethanol water mixture, in equal amounts. The swabs are then extracted, cleaned up and analyzed using Gas Chromatographs with Thermal Energy Analyzer detectors. This paper follows on from a previous published paper describing the regime and summarizing subsequent results from approximately 6 years of tests. Lessons learned and improvements made over the period are also discussed. Monitoring samples taken from surfaces within the trace laboratories and trace vehicle examination bay have, with few exceptions, revealed only low levels of contamination, predominantly of RDX. Analysis of the control swabs, processed alongside the monitoring swabs, has demonstrated that in this environment the risk of forensic sample contamination, assuming all the relevant anti-contamination procedures have been followed, is so small that it is considered to be negligible. The monitoring regime has also been valuable in assessing the process of continuous improvement, allowing sources of contamination transfer into the trace areas to be identified and eliminated.

Y la sola insinuación de que el DNT sea capaz de contaminar nada -aparte de nuestras enfermizas mentes- resulta simplemente ofensiva.

Many military facilities across the United States have been declared Superfund sites due to extensive contamination caused by the production, packing, and firing of a variety of munitions. In Eastern and Western Europe explosive contaminated sites are even more widespread. Two compounds—2 4,6- trinitrotoluene (TNT) and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX)—are the major ingredients in nearly all military munitions. While TNT and RDX are the contaminants most frequently detected in the soil and groundwater at contaminated sites, by-products and biotransformation compounds, such as 2,4-dinitrotoluene (2,4-DNT) and 4-amino-2,6-dinitrotoluene (4AmDNT), are also often present. Onsite analytical methods for explosives are used to quickly characterize the extent of contamination and to reduce the number of non-detect samples sent offsite for expensive laboratory analyses. Operating principles of field-portable technologies for the measurement of explosive residues such as RDX and TNT are varied and include: gas chromatography with ion mobility spectrometer or thermoionic detection and flow-through immunoassay techniques with fluorescence detection and surface plasmon resonance. The performance factors of four technologies have been verified for detecting and quantifying explosives and their by-products in soil and/or water. Product and contact information for the participating vendors is included below.

Termino con una referencia muy interesante sobre detección de explosivos a distancia. No basada en la lectura de los posos del café, sino en la volatilidad de los componentes habituales de explosivos, incluido el DNT.

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Los explosivos [empleados en la prueba] eran de 500 gramos de peso. En el caso de la dinamita sólo se utilizaron 125 gramos debido a la alta volatilidad e la nitroglicerina y el nitroglicol, que incrementaba el riesgo de contaminación.(...)

Se desarrolló un método basado en columna de CG con ECD para la detección de TNT, tetryl, DNT (2,4), DNT (2,6) y RDX en agua corriente.

(...)