Chemical and Biological Agents and Radiation
Hydrogen cyanide (HCN): HCN is a highly toxic chemical blood agent in the form of a colorless gas. Cardiovascular, neurological, respiratory and thyroid effects can occur as a result of chronic low exposure to HCN (Blanc, Hogan, Hryhorczuk, Hessl & Bernard, 1985). In case of exposure to liquid HCL, mild soapy water can be used for decontamination. Either sodium or amyl nitrite combined with sodium thiosulfate can be can be used as an antidote for the effects of HCN poisoning (USAMRICD, 2000). Treating patients with poor oxygen-carrying capacity can be a bit challenging because nitrite-induced methemoglobinemia can be harmful. (Chandra, Gupta, Bhargava, Clerk & Mahendra, 1980) In WWII, HCN was used as Zyklon B and in gas chambers by the Germans ("The zyklon," 1946).
Ricin: Ricin or Ricin toxin is a Category B threat agent in the form of protein extracted from castor beans ("Facts about ricin," 2008). Exposure to Ricin can occur through ingestion, inhalation, or injection. A robust immune response is produced by ricin intoxication and within 36 to 72 hours, it can lead to death (Spivak & Hendrickson, 2005). Although ricin can be transmitted from one human to another, washing with 0.1% sodium hypochlorite can help with decontamination (Audi, Belson, Patel, Schier & Osterloh, 2005). There are no FDA approved treatments for ricin poisoning but supportive therapy can be provided to patients (Poli, Roy & Huebner , 2007). As a biological weapon, ricin is most likely aerosolized in the form of a mist or powder ("Bioterrorism agents/diseases," ).
Caesium-137: Caesium-137 or radiocaesium is a radiological by-product that is formed when f weapons-grade radioactive substances are manufactured, specifically Uranium-235 ("Dictionary of radiation," 2011). The effects of exposure to Cs-137 on human health are of greater concern because the energy released can damage living cells significantly. Beta particles and gamma rays are emitted by Cs-137 that disrupt cellular function and cause tissue damage (Coggle, 1986). Cs-137 can be reduced by removing outer clothing and external contamination can be washed off ("Cesium-137 (cs 137)," 2007). In case of Cs-137 contamination, fecal excretion can be accelerated by using Prussian blue, or lavage and purgatives (Ansari, 2007). Cs-137 can be used in the form of an explosive RDD, such as a dirty bomb (White, 2007).
Decontamination is a combination of cleansing and disinfection of the human body in case of contamination by dangerous chemical, biological or radiological agents. In most situations involving contamination, the process of decontamination is carried out in four stages. In the first stage, individuals who are believed to be contaminated are taken to different decontamination pods, tents or trailers according to their gender. In the second stage they enter a strip-down room in the pod, tent or trailer they remove their clothes that might possibly be contaminated. In the third stage they are showered in a special wash-down room. In the fourth stage they go to a drying room where they are dried and either a white Tyvek or cleaning is issued to them (SBCCOM, 2000).
Incidents involving potential risk of hazardous contamination can take place anywhere, at any time; this is why different factors have to be considered during the decontamination process under different circumstances. For instance, in case of a contamination incident during the winter, providing warm showers and blankets is a very basic, initial consideration that should be kept in mind, especially for the elderly and children since they are at a higher risk of hypothermia (SBCCOM, 2002). It is quite normal to have infants present on the scene of a contamination incident and they must be decontaminated as well. Infants get to get slippery when wet, so getting them through the process of decontamination safely must be taken into consideration, maybe by using car seats, plastic buckets and/or stretchers ("Section 8 -," ).
DNA Identification after Mass Disasters
After the September 11 attacks, the most difficult task that the country’s forensic community had to undertake was identifying the victims. After mass disasters, DNA analysis is the most reliable way of identifying human remains. According to Robert Shaler, out of different modes of identification, the most dependable and strong is DNA analysis. He said that the collection of DNA evidence is vital, whether or not dental and fingerprint records are available (Shaler, 2007). When traditional anthropological and physical characteristics are absent, identifying a biological sample and associating body parts becomes possible through forensic DNA typing. Over other methods of identification, DNA analysis is a critical tool and has numerous benefits, especially when it comes to association of unidentifiable remains with victims, such as the ones from September 11 attacks. DNA profiling is also beneficial in mass disaster situations.
DNA profiling can be used to identify victims of mass disasters when adequate amounts of typable DNA and information reference samples are available. It is possible to use DNA analysis even when human remains recovered are rather small. Often, when unidentifiable remains cannot be re-associated with victims, DNA analysis seems to be the only viable option left to do so. However, it must be kept in mind that some effort, time, skilled, specialized personnel and tools are needed for DNA identification testing. After mass disasters, it is important to use the best forensic practices for the appropriate collection and preservation of DNA samples. Additionally, if the DNA samples are not properly collected and preserved, it is possible to lose typable DNA and the ability to identify remains can be compromised. In case of a mass disaster where bulk of remains turn up, a laboratory must have some plan which allows them to use this forensic technique. This is why it is a good idea to shift toward DNA based identifications ("Dna identifications after," 2005).
Respiratory Protection
Protective ensembles are a form of personal protective clothing, which are worn to protect from CBRN hazards. Class 4 ensembles, in particular, are a set of protective clothing, boots, gloves, and respirator that are used by first responders and law enforcement personnel at terrorism incidents that involve hazardous biological or radiological particulate (Maniscalco & Christen, 2010). Class 4 ensembles are worn at terrorism incidents where CBRN compliant PAPR or APR are not permitted to be used because of concentrations below IDLH levels ("Ensemble, law enforcement," 2011). The THL (Total Heat Loss) requirements of the barrier materials of Class 4 ensembles are higher than those of Class 3 ensembles ("Standards for chemical,," ).The functionality of Class 4 ensembles is tested. The function for which Class 4 ensembles are designed is to prevent biological or radiological particulates from leaking inward.
A particle-tight integrity test is performed to test this. The limitations of Class 4 ensembles is that protection against chemical agents or toxic industrial chemical agents, whether in the form of aerosols, gases, or vapors, is not offered by them. Class 4 ensembles offer limited liquid protection, primarily so that wet decontamination is enabled (Maniscalco & Christen, 2010). Class 4 ensembles are intended to be worn for longer periods, so in most cases air-purifying respirators ("Lion apparel mass," 2009). Since Class 4 ensembles indeed offer protection against biological agents (Maniscalco & Christen, 2010), so a Class 4 ensemble can be used a first responder in a bioterrorism incident involving anthrax, such as the 2001 anthrax attacks ("Amerithrax or anthrax," ). The Class 4 ensembles would protect a first responder from getting infected by anthrax spores. This would not only allow them to perform their duties more efficiently and safely, but would also prevent the risk of infection while collection evidence that might have anthrax spores on them. The air-purifying respirator within the Class 4 ensemble would also protect the first responder from getting infected by inhaling the anthrax spores.
First Responder Concerns and Preservation of Evidence
While looking in horror as the South Tower of the World Trade Center collapses, the biggest concern for me as a first responder would the exposure to all that toxic dust and the medical problems, both physical and mental (Hutchison, 2011), it could result it. Despite my commitment to the job and as a moral obligation, I would still be concerned whether or not my ensemble would protect me from the potential risks of contamination. As a first responder, I would not hesitate to oblige to my duties and help out as best as I could, but at the back of my head I would certainly be concerned about the health problems, from breathing problems to cancers, that I as well as my fellow first responder teammates and citizens would incur in the wake of this disaster, especially because of that massive cloud of dust (Chamberlin, 2012).
As a first responder, my first priority would be to save lives, help stabilize the incident and then focus on identifying and preserving evidence. I would start by assessing the scene to look for victims that might need assistance and for any potential evidence. I would tape off the scene of the incident in order to prevent the contamination of the evidence. In the interest of preserving the scene of the incident and the evidence, I would take careful note of who comes in and out. I would make sure record every detail carefully, especially those surrounding potential evidence, in case the original scene of the incident is altered. I would then wait for the forensic experts and hand over any records that I have taken so they can carry on with the chain of custody of the evidence ("Preserving forensic evidence," ).
References
Hutchison, C. (2011). 9/11 first responders plagued by health problems from toxic dust and debris. Retrieved from http://abcnews.go.com/Health/Wellness/911-responders-plagued-cancer-asthma-ptsd/story?id=14427512
Chamberlin, B. (2012). Government admits toxic 9/11 dust caused cancer for first responders. Retrieved from http://nyulocal.com/national/2012/09/12/government-admits-toxic-911-dust-caused-cancer-for-first-responders
Preserving forensic evidence at crime scenes. (n.d.). Retrieved from https://healthtraining.inhs.org/uploadedFiles/EMS_Live_at_Nite/2011/January_11_2011/Jan 11 Handouts.pdf
Maniscalco, P. M., & Christen, H. T. (2010). Homeland security, principles and practice of terrorism response. (1 ed.). Jones & Bartlett Publishers. Retrieved from http://books.google.com.pk/books?id=MmRevVELkfsC&pg=PA191&lpg=PA191&dq=class 4 protective ensemble&source=bl&ots=234refs12h&sig=jlpXmEQ6MPuTwVcF-kBYQjAEIiQ&hl=en&sa=X&ei=emJpUKLbCMKh4gTJvoHoDA&ved=0CEwQ6AEwCA
Ensemble, law enforcement cbrn protective, nij 0116.00 (lerl-4). (2011). Retrieved from https://iab.gov/SELDetail.aspx?DocumentId=44
Standards for chemical, biological, radioactive, and nuclear protective ensembles. (n.d.). Retrieved from http://www2.dupont.com/personal-protection/en-us/dpt/article/nfpa-1994.html
Lion apparel mass incident garment nfpa 1994 class 3 ensemble. (2009). Retrieved from http://www.lionprotects.com/sites/lion.peritusinteractive.com/files/legacy-pdf/MIG User Guide.pdf
Amerithrax or anthrax investigation. (n.d.). Retrieved from http://www.fbi.gov/about-us/history/famous-cases/anthrax-amerithrax/amerithrax-investigation
Shaler, R. C. (2007). Who they were: Inside the world trade center dna story. (1 ed.). Free Press. Retrieved from http://books.google.com.pk/books?id=eI1pVWM38wEC&q=dna analysis (2005). Dna identifications after the 9/11 world trade center attack. Science, 310(5751), 1122-1123. Retrieved from http://www.sciencemag.org/content/310/5751/1122.summary
