Aluminium phosphide (ALP) is an effective solid pesticide commonly used for preserving grain. It is a commonly encountered poisoning in developing countries including Iran and India and has drawn worldwide attention since it is considered as a life-threatening condition without an efficient antidote. While studies are going on to develop an effective antidote, some chemicals are used to help patients to recover from this poisoning. Predictive factors have been elucidated to determine which patient would have better or worse condition. Authors of related case reports have tried to attribute it to ignition of highly flammable phosphine gas. If this is true, there should be a source of commencement of thermal reaction; in some cases this has been suggested to originate from the friction during nasogastric tube insertion or negative pressure induced by suctioning. We are presenting a case of ALP poisoning that appeared as internal ignition with hot charcoal vomitus. The literature was reviewed for all case reports of internal ignition in ALP poisoning.
A 34-year-old woman was brought to the emergency department with alleged history of taking ALP tablets. Her relatives revealed the aluminium canister of ALP tablets and alleged she had taken 2 tablets 30 min before. On arrival, she was drowsy and was not responding to verbal commands. Her body was cold and hypotonic, and her skin was pale with mottling. Her vital signs were as follows: Pulse rate 110/min regular, blood pressure 70/52 mm Hg, respiratory rate 20/min, shallow and body temperature, 36.1°C. On emergency investigations, the electrocardiogram showed sinus tachycardia, pulse oximetry showed O2 saturation of 91% on room air and arterial blood gas analysis demonstrated metabolic acidosis with pH of 7.1. Presentation of ALP tablets by the family and symptoms of patient favoured diagnosis of ALP poisoning. The patient was instantly attended to; intubation was carried out, and a nasogastric tube was inserted. Normal saline was administered by infusion intravenously. After gastric washing with sodium bicarbonate, gastric lavage was performed using potassium permanganate (1:10,000) and then activated charcoal (100 g) was administered. Shortly afterwards, she vomited hot charcoal filled with small bubbles covered with white smoke that led to thermal burning of the left side of the her face. A simultaneous cough splashed some vomit on the personnel's clothes. She was immediately transferred to an isolated room and underwent infusion of calcium gluconate and magnesium sulphate. The patient's situation progressively deteriorated. Sensorium decreased and apnoea occured necessitating resuscitation and mechanical ventilation. At 3 h after emergency department admission, the patient had cardiac arrest and died.
Using Google Scholar, PubMed and Scopus databases, the terms’ ignition, thermal injury, exothermic reaction and physical damage were searched under ‘ALP’ category. Six cases of thermal injury in ALP poisoning were found in five papers that had been published in the literature during 2007–2012. A summary of case reports along with the present report is shown in Table 1. In the case reports mentioned, the mechanisms of ignition are diverse and implicate the poison's byproducts, patient and environment factors as contributing factors.
ALP is not flammable. However, it reacts readily with water and acids to produce hydrogen phosphide (phosphine) and a small amount of diphosphine. Phosphine imposes its toxicity with inhibition of cytochrome oxidase that leads to metabolic disturbances and internal organ damages. Methaemoglobinemia and haemolysis, acute pancreatitis, oesophagobronchial fistula and polyserositis are regarded as uncommon complications of ALP poisoning. Internal ignition and thermal injury following ALP poisoning is another interesting and unusual complication that may complicate the patient's condition and may be a hazard to the medical personnel.
Phosphine and diphosphine may ignite spontaneously at air concentrations above the lower explosive (flammable) limit (LEL) of 1.8% v/v. Phosphine causes corrosion and may induce an exothermic reaction at higher temperatures, especially above 30°C. When phosphine burns, it produces a dense white cloud of ‘phosphorus pentoxide’, a severe respiratory tract irritant. ALP is incompatible with oxidising agents, which means it induces adverse reactions. Potassium permanganate is recommended in ALP poisoning to convert phosphine to phosphate, but it is an oxidising agent and when in contact with organic matter, it is reduced to manganese dioxide and the very corrosive potassium hydroxide. This reaction is also exothermic and may have contributed in increasing injury as well as the occurrence of ignition events. Soltaninejad et al. suggest that permanganate-induced toxicity occurs when saturated solution is ingested and not the diluted solution (1:10,000) that is used in decontamination of the patient, but the dilution is usually not supervised in emergency departments and the exothermic reaction may occur even in the diluted form. Even though it is suggested that negative pressure during gastric suctioning may contribute to ignition, practically, negative pressures are designed for an exhaust ventilation system in gas cabinets relative to surrounding areas for safety purposes and have not been documented to act as starting points of ignition. An event is reported outside the hospital where ignition happened in the absence of therapeutic interventions.
Phosphine, diphosphine and its by-products may impose a threat to the health personnel that would need preventive measures, even evacuation. Physical damage is rare in this poisoning and has frequently been reported in the case of ignition. Thermal injury further increases damage and is an additional risk to medical personnel. The reason why the combustion injury is rarely reported in spite of multiple cases of ALP poisoning is not clear. This event may occur internally without external manifestations in many instances.
ALP poisoning warrants aggressive management, and emergency departments need to be prepared adequately to handle the patients. The occurrence of ignition with the release of phosphine from ALP poisoned patients can affect not just the patient but also pose a health hazard to emergency physicians and medical staff. The mechanism of the ignition is still not well-understood and may vary from patient to patient.
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1. Moghadamnia AA. An update on toxicology of aluminum phosphide Daru. 2012;20:25
2. Louriz M, Dendane T, Abidi K, Madani N, Abouqal R, Zeggwagh AA. Prognostic factors of acute aluminum phosphide poisoning Indian J Med Sci. 2009;63:227–34
3. Akinci E, Kocasaban DU, Vural K, Coskun F. Secondary intoxication of emergency department personnel with a flammable and highly toxic gas: A lethal aluminum phosphide poisoning case Hong Kong J Emerg Med. 2012;19:54–7
4. Wahab A, Rabbani MU, Wahab S, Khan RA. Spontaneous self-ignition in a case of acute aluminium phosphide poisoning Am J Emerg Med. 2009;27:752.e5–6
5. Shadnia S, Soltaninejad K. Spontaneous ignition due to intentional acute aluminum phosphide poisoning J Emerg Med. 2011;40:179–81
6. Yadav J, Athawal BK, Dubey BP, Yadav VK. Spontaneous ignition in case of celphos poisoning Am J Forensic Med Pathol. 2007;28:353–5
7. Rai S, Narwade SH, Rane S. Spontaneous ignition in case of aluminum phosphide poisoning Bombay Hosp J. 2011;53:473–77
8. Soltaninejad K, Nelson LS, Khodakarim N, Dadvar Z, Shadnia S. Unusual complication of aluminum phosphide poisoning: Development of hemolysis and methemoglobinemia and its successful treatment Indian J Crit Care Med. 2011;15:117–9
9. Verma SK, Ahmad S, Shirazi N, Barthwal SP, Khurana D, Chugh M, et al Acute pancreatitis: A lesser-known complication of aluminum phosphide poisoning Hum Exp Toxicol. 2007;26:979–81
10. Bhargava S, Rastogi R, Agarwal A, Jindal G. Esophagobronchial fistula-A rare complication of aluminum phosphide poisoning Ann Thorac Med. 2011;6:41–2
11. Bhalla A, Mahi S, Sharma N, Singh S. Polyserositis: An unusual complication of aluminum phosphide poisoning Asia Pac J Med Toxicol. 2012;1:14–7
12. Nocera A, Levitin HW, Hilton JM. Dangerous bodies: A case of fatal aluminium phosphide poisoning Med J Aust. 2000;173:133–5
13. Kerby K, Hanfling D, Puccio E. Aluminum phosphide suicide: Emerging threat to healthcare workers J Emerg Disaster Med. 2012;8:1–5
14. The Emergency Response Safety and Health Database, Centers for Disease Control and Prevention.Last accessed on 2015 May 31 Available from: http://www.cdc.gov/niosh/ershdb/emergencyresponsecard_29750035.html
15. . Material Safety Data Sheet United Phosphorus, Inc..Last accessed on 2014 May 17 Available from: http://www.sfm.state.or.us/CR2K_SubDB/MSDS/WEEVIL_CIDE_PELLETS.PDF
16. Dagli AJ, Golden D, Finkel M, Austin E. Pyloric stenosis following ingestion of potassium permanganate Am J Dig Dis. 1973;18:1091–4
17. Kochhar R, Das K, Mehta SK. Potassium permanganate induced oesophageal stricture Hum Toxicol. 1986;5:393–4
18. . Summary of Human Toxicity, Potassium Permanganate The Chemical Incident Management Handbook.Last accessed on 2015 May 17 Available from: http://www.shpir.hps.scot.nhs.uk/htm/hps/documents/cirs/26157.htm
19. Soltaninejad K, Nelson LS, Khodakarim N, Dadvar Z, Shadnia S. Authors’ reply Indian J Crit Care Med. 2012;16:246
20. . Code of Practice Phosphine, Globally Harmonized Document Asia Industrial Gases Association. AIGA051/08.Last accessed on 2015 May 31 Available from: http://www.asiaiga.org/docs/AIGA%20051_08%20Code%20of%20Practice_%20Phosphine%20reformat%20Jan%2012.pdf