Aluminum phosphide poisoning--a review

Accidental Aluminum Phosphide Intoxication Successfully Treated with Hyperbaric Oxygen Therapy: A Case Report

The most common pesticide agents are organophosphates and phosphides, aluminum phosphide (ALP) in particular. ALP is a major cause of suicidal poisoning in many countries. In other countries, the problem of accidental, mainly occupational-related, poisoning is also real and actual. Almost two thirds of individuals in poisoning cases have died. This case report describes a case of a patient with accidental ALP intoxication. The origin of the poisoning was the fumigation of stored grain in an agricultural building adjacent to the building in which patient was temporarily housed, while both buildings were connected by an underground corridor, through which the released poison gas penetrated. The case was originally presented by the rescuers as well as healthcare professionals of the local hospital as carbon monoxide intoxication, which has a similar symptomatology as ALP intoxication. The patient was treated comprehensively, including using the HBOT method, which is very unique in the case of phosphine intoxication in human medicine, with an excellent final clinical outcome. This was the first described case of HBOT for ALP intoxication in clinical medicine, although the HBOT indication itself became a coincidence in this case. Further studies must be undertaken to demonstrate the effectiveness of HBOT in treating patients with ALP poisoning.

Toxicoepidemiology of Phosphide Poisoning in the Central Part of Iran

Objective

Aluminum phosphide (ALP) and zinc phosphide (ZnP) are toxic agrochemical pesticides, which are commonly used as an agent of self-harm in developing countries. Because of high toxicity of phosphides, we evaluated toxico-epidemiology ALP and ZnP poisoning in with respect to outcome.

Methods

We performed a cross-sectional study with retrospective chart review including the records for patients admitted due to phosphide poisoning (ALP, ZnP) in a poisoning referral center in Khorshid Hospital, affiliated with Isfahan University of Medial Sciences, Isfahan, Iran. Demographic characteristics, clinical manifestations, outcome (survived or death), and length of hospital stay for the patients were recorded in a data collecting form. Binary backward stepwise logistic regression was used for outcome prediction.

Findings

Sixty patients were evaluated in the study. The mean age of patients was 27.61. Thirty-nine patients were men. 96.7% of the patients ingested it intentionally. Most of the patients on admission were conscious (66.7%). Abnormality of EKG was noted in 8.3%. The mortality in ALP and ZnP poisoning was 39.2% and 22.2%, respectively. Serum bicarbonate and base excess in the venous blood gas analysis, systolic blood pressure, and serum sodium level were significantly different between patients with ALP and ZnP poisoning on admission time (P < 0.05). On admission, systolic blood pressure was an important predictive factor for mortality (odds ratio 4.87; 95% confidence interval: 1.5-15.45; P = 0.007).

Conclusion

The rate of mortality in phosphide poisoning is high. Knowing predictive factors for mortality help physicians for selecting patients in intensive care unit admission and aggressive treatment.

Evidence for the efficacy of the emetic PP796 in paraquat SL20 formulations - a narrative review of published and unpublished evidence

BACKGROUND

The bipyridyl herbicide paraquat was first introduced into agriculture in the 1960s by Imperial Chemical Industries. Due to issues with unintentional poisoning, the centrally acting emetic PP796 was added in 1976 to the company's 20% paraquat ion soluble liquid (SL20) formulations (Gramoxone^®) at a concentration of 0.5 g/L or 0.05% (equivalent to 0.071 mg/kg in a 70 kg adult ingesting a minimum lethal dose of 10 mL) to induce early vomiting (within 30 min), reduce paraquat absorption from the gut, and prevent deaths. Its presence in paraquat products was subsequently mandated by the Food and Agriculture Organization Committee of Experts on Pesticides in Agriculture (predecessor to the current FAO/WHO Joint Meeting on Pesticide Specifications). However, no primary pre-clinical or clinical data have been published regarding the effectiveness of PP796. We reviewed the published literature and unpublished company reports for data on the effectiveness of PP796.

METHODS

PubMed and Google were searched for published studies on the emetic using the search terms "paraquat" and ["emetic" or "PP796"]. Company documents reporting pre-clinical and clinical studies were accessed at the website of U.S. Right to Know (https://usrtk.org/pesticides/paraquat-papers/). Primary study reports were sought as well as overviews written by company toxicologists.

RESULTS

Pre-clinical dog and monkey studies indicated that the PP796 EC50 dose for vomiting was around 0.5-2 mg/kg. Further increasing the PP796 concentration speeded up the time to first vomit and reduced the amount of paraquat absorbed (as assessed by the 0-24 h plasma area-under-the-curve) 100-fold compared to a control group receiving no PP796. However, the dose selected for paraquat SL20 formulations by the company (0.5 g/L or 0.05%) was based exclusively on a phase II study in the early 1970s involving five volunteers receiving 3 different doses, with only two individuals actually vomiting, supplemented by data from 37 patients taking 2 mg in clinical trials. A UK-mandated toxicovigilance study in the 1980s identified only 21 patients ingesting paraquat SL20 with PP796 for whom data on time to vomit was available; of these patients, 11 vomited within 30 min (52.4%, 95%CI 31-73.7%). No effect on mortality could be identified from any study of paraquat SL containing 0.05% PP796. A clinical study in Sri Lanka 30 years after the emetic was first introduced, of a revised formulation (Gramoxone^® Inteon) containing a three-fold higher amount of PP796, as well as MgSO4 and an alginate, showed increased rates of early vomiting and modestly reduced mortality for patients ingesting up to 100 mL.

CONCLUSION

Pre-clinical studies showed a clear dose response for PP796 to cause early vomiting, with effective doses in the 0.5-20 mg/kg range. A too low concentration of PP796 was selected for paraquat formulations based on an inadequate phase II study. Currently, evidence that PP796 at 0.05% in paraquat SL20 causes more rapid vomiting after ingestion is weak or unpublished; no evidence of clinical benefit or fewer deaths has been identified. There is no evidence to support the FAO/WHO Joint Meeting on Pesticide Specifications mandate to include PP796 or any other emetic in paraquat products. Products with higher emetic concentrations have been developed but are not widely used; it is possible they may prevent deaths.

Modification of the hemodynamic and molecular features of phosphine, a potent mitochondrial toxicant in the heart, by cannabidiol

Aluminum phosphide (AlP) poisoning is common in many countries responsible for high mortality. The heart is the main target organ in AlP poisoning. Several studies have reported the beneficial effects of cannabidiol (CBD) in reducing heart injuries. This study aimed to investigate the possible protective effect of CBD on cardiac toxicity caused by AlP poisoning. Study groups included almond oil, normal saline, sole CBD (100 µg/kg), AlP (11.5 mg/kg), and four groups of AlP + CBD (following AlP gavage, CBD administrated at doses of 5, 25, 50, and 100 μg/kg via intravenous (iv) injection). Thirty minutes after AlP treatment, an electronic cardiovascular device (PowerLab) was used to record electrocardiographic (ECG) changes, heart rate (HR), and blood pressure (BP) for three hours. Cardiac tissue was examined for the activities of mitochondrial complexes, ADP/ATP ratio, the release of cytochrome C, mitochondrial membrane potential (MMP), apoptosis, oxidative stress parameter, and cardiac biomarkers at 12 and 24 hours time points. AlP administration caused abnormal ECG, decreased HR, and BP. AlP also significantly reduced mitochondrial complex I and IV activity and ADP/ATP ratio. The level of cytochrome C release, apoptosis, oxidative stress, and cardiac biomarkers was considerably increased by AlP, which was compensated following CBD administration. CBD was able to improve hemodynamic function to some extent in AlP poisoned rats. CBD restored ATP levels and mitochondrial function and decreased oxidative damage and thus, prevented the heart cells from entering the apoptotic stage. Further clinical trials are needed to explore any possible benefits of CBD in AlP-poisoned patients.

Antidotal effect of dihydroxyacetone against phosphine poisoning in mice

Phosphine (PH₃ ) is widely used as an insecticide and rodenticide. On the contrary, many cases of PH₃ poisoning have been reported worldwide. Unfortunately, there is no specific antidote against PH₃ toxicity. Disruption of mitochondrial function and energy metabolism is a well-known mechanism of PH₃ cytotoxicity. Dihydroxyacetone (DHA) is an adenosine triphosphate supplying agent which significantly improves mitochondrial function. The current study was designed to evaluate DHA's effect on inhalational PH₃ poisoning in an animal model. DHA was injected into BALB/c mice before and/or after the start of the PH₃ inhalation. The cytochrome c oxidase activity was assessed in the animals' brain, heart, and liver exposed to PH₃ (for 15, 30, and 60 min, with and without the antidote). The LC₅₀ of PH₃ was calculated to be 18.02 (15.42-20.55) ppm over 2 h of exposure. Pretreatment of DHA (1 or 2 g/kg) increased the LC₅₀ of PH₃ by about 1.6- or 3-fold, respectively. Posttreatment with DHA (2 g/kg) increased the LC₅₀ of PH₃ by about 1.4-fold. PH₃ inhibited the activity of cytochrome c oxidase in the assessed organs. It was found that DHA treatment restored mitochondrial cytochrome c oxidase activity. These findings suggested that DHA could be an effective antidote for PH₃ poisoning.

Acute aluminum phosphide poisoning: The menace of phosphine exposure

Aluminum phosphide (AlP) is a popular fumigant used widely for the safe storage of food grain. Although A1P is free from toxic residues, it releases phosphine which acts on mitochondrial components of almost all types of pests. Unfortunately A1P is also a common suicidal agent in developing countries with no known antidote. In addition, accidental exposure to phosphine may also occur. AlP poisoning affects cardiac and vascular tissue directly and can result in multiorgan system failure leading to death in severe cases. There is no specific biomarker for diagnosing AlP poisoning and management depends on a high level of clinical suspicion. Although acetylcholinesterase has been suggested as a surrogate biomarker of AlP exposure, there are opposing views. In this review, we analyzed the relevant published material with emphasis on the need to recognize and explore the use of plasma mitochondrial enzyme activity as a potential biomarker for AlP exposure.

Development of detection methods for the diagnosis and analysis of highly toxic metal phosphides: A comprehensive and critical review

Metal phosphides, especially aluminum phosphide, and phosphine (PH₃ ) are widely used as insecticides and rodenticides for protection of grains during process of storage and transportation. The main reason of poisoning with this compound is related to the conscious ingestion of salts or accidental inhalation of PH₃ . So the early and accurate diagnosis of poisoning can significantly help to the effective clinical treatment or recognition of death cause. PH₃ is somewhat unstable due to reaction with oxygen or hemoglobin leading to formation of oxy-acids phosphorous. Here, we critically reviewed the literature introducing the quantitative and qualitative methods for the detection of metal phosphides, PH₃ , and its products. This study obviously demonstrates that during past years, different diagnosis methods have been remarkably progressed. Head-space gas chromatography and confirmatory colorimetric methods have been as the most popular techniques. Also, the gas sensors are a promising method that must be more progressed.

Investigating the outcomes of aluminum phosphide poisoning in khorshid referral hospital, Isfahan, Iran: A retrospective study

Objective:

Aluminum phosphide (ALP) (rice-tablet) is a common cause of adult poisoning in Iran, including Isfahan. So far, no effective treatment has been identified for this poisoning. We aimed to investigate the outcome of ALP poisoned patients admitted to the clinical toxicology ward of Khorshid Hospital in Isfahan from 2017 to 2019.

Methods:

This chart-review study was performed on the population of ALP poisoned patients admitted to the clinical toxicology ward of Khorshid University Hospital from 2017 to 2019 treated with the hospital’s new treatment protocol, using the complete enumeration approach. The outcomes were determined by reviewing and abstracting medical charts of ALP poisoned patients from the hospital archive.

Findings:

The most common complaints at admission were depressed consciousness (41.9%) and vomiting (32.2%). There was no significant change in blood sugar, pH, base excess (BE), and venous blood bicarbonate throughout their hospitalization (P > 0.05). Treatment outcomes had a significant relationship with blood pH 2 h and 6 h after admission and the BE 6 h after admission (P < 0.05). There was also a significant relationship between the outcome and the length of stay, initial ejection fraction (EF), and EF in predischarge echocardiography (P < 0.05). Out of 31 patients, 24 (77.4%) died within 72 h, 5 (16.1%) recovered without any complication, and 2 (6.5%) recovered with some complications.

Conclusion:

The mortality rate of ALP poisoned patients was reasonably high and can be attributed to the poor efficacy of the new treatment protocol or the long time it takes for patients to reach the hospital and start receiving treatments.

Cardioprotective activity of ethanolic extract of Echinophora cinerea against aluminum phosphide poisoning in rats

Rice tablet, also known as aluminum phosphide (ALP), is a nonorganic material used as an insecticide and rodenticide in the storage and transportation of grains. Phosphine gas, released from the chemical material, in contact with humidity and weak acid, can induce poisoning and death. This study was conducted to investigate the effect of ethanol extract of Echinophora cinerea leaves on ALP poisoning in heart in rats. In this study, factors such as blood pressure, heart rate, electrocardiography, and biochemical biomarkers of oxidative stress of cardiac tissue were evaluated. The use of Echinophora extract at a dose of 200 mg per/kg primarily improved bradycardia, hypotension, and cardiac conduction. Echinophora extract at a dose of 400 mg could protect body against oxidative stress. It seems that Echinophora extract has significant clinical positive effects that can be employed in treatment protocols of acute poisoning associated with ALP. PRACTICAL APPLICATIONS: Administration of the Echinophora cinerea extract can improve bradycardia, hypotension, and conduction disturbances of the heart caused by poisoning with rice tablet. E. cinerea extract also can increase the levels of antioxidant enzymes and protect the body against oxidative damage caused by poisoning with rice tablet. Therefore, Echinophora extract has significant clinical positive effects that can be used in treatment protocols of acute poisoning associated with aluminum phosphide.

"PGI Score": A Simplified Three-point Prognostic Score for Acute Aluminum Phosphide Poisoning

Introduction

Aluminum phosphide (AlP) ingestion for self-harm is associated with a high case-fatality rate (CFR) in low- and middle-income countries. A reliable and accurate prognostic scoring tool is required for appropriate triaging, to guide clinical decision-making, and to evaluate the efficacy of therapeutic interventions for the patients with AlP toxicity.

Materials and methods

We performed a prospective cohort study in a tertiary care hospital in north India in patients aged 15 years and over with acute AlP poisoning, investigating the parameters associated with CFR, and developing a reliable and simple prediction score.

Results

The CFR was 51% in this cohort of 105 patients. Three parameters—pH <7.25, score on Glasgow coma scale (GCS) <13, and systolic blood pressure (SBP) <87 mm Hg were most robust predictors of CFR (odds ratio; 12.614, 18.621, and 17.600, respectively; area under the receiver operating characteristic curve—0.808, 0.796, and 0.776, respectively). Based on these parameters (with 1 point to each), a prognostic score was developed, ranging from 0 to 3 points. A total score of 3 had a 98.2% specificity and a positive predictive value of 96.4%, whereas a score ≤1 had a 100% sensitivity and 100% negative predictive value.

Conclusion

A scoring system based on low pH (P), low GCS score (G), and impaired or low SBP (I) (“PGI” score) may provide a simplified predictive model for mortality in AlP poisoning.

How to cite this article

Pannu AK, Bhalla A, Sharma A, Sharma N. “PGI Score”: A Simplified Three-point Prognostic Score for Acute Aluminum Phosphide Poisoning. Indian J Crit Care Med 2020;24(9):790–793.

The role of minocycline in alleviating aluminum phosphide-induced cardiac hemodynamic and renal toxicity

Poisoning with aluminum phosphide (AlP) has been attributed to the high rate of mortality among many Asian countries. It affects several organs, mainly heart and kidney. Numerous literature demonstrated the valuable effect of minocycline in mitigating pathological symptoms of heart and kidney disease. The aim of the present study was to evaluate the probable protective effect of minocycline on cardiac hemodynamic parameters abnormalities and renal toxicity induced by AlP-poisoning in the rat model. AlP was administered by gavage at 12 mg/kg body weight followed by injection of minocycline for two interval times of 12 and 24 h, at 40, 80, 120 mg/kg body weight. Electrocardiographic (ECG) parameters were monitored, 30 min after AlP gavage for 6 h using an electronic cardiovascular monitoring device. Kidney tissue and serum were collected for the study of histology, mitochondrial complexes I, II, IV, lactate dehydrogenase (LDH) and myeloperoxidase (MPO) activity, ADP/ATP ratio, mitochondrial cytochrome c release, apoptosis, lactate, BUN, and Cr levels. The results demonstrated that AlP induces ECG abnormalities, and failure of heart rate and blood pressure, which improved significantly by minocycline. Minocycline treatment significantly improved complexes I, IV, MPO and LDH activities, and also reduced the ADP/ATP ratio, lactate level, release of cytochrome c, and apoptosis in the kidney following AlP-poisoning. Also, the histological results showed an improvement of kidney injury in minocycline treated groups. In conclusion, the findings of this study showed that minocycline could improve cardiac hemodynamic abnormalities and kidney injury following AlP-poisoning, suggesting minocycline might be a possible candidate for the treatment of AlP-poisoning.

Mortality from aluminum phosphide poisoning in Kermanshah Province, Iran: characteristics and predictive factors

OBJECTIVES

Aluminum phosphide (ALP), also known in Iran as rice tablets, is one of the most effective rodenticides used to protect stored grain. However, ALP poisoning regularly causes mortality in humans. The aim of this study was to evaluate the characteristics and predictive factors of mortality from ALP poisoning.

METHODS

This study evaluated all patients with ALP poisoning referred to Imam Khomeini Hospital in Kermanshah Province, Iran from 2014 to 2015. For each patient, the following information was recorded: age, sex, the number of tablets consumed, the number of suicide attempts, the time elapsed from consumption to treatment, blood pressure, blood pH, HCO3 levels, and PCO2 . Differences between the survivors and non-survivors of ALP poisoning were analyzed using univariate logistic regression and multivariate analysis.

RESULTS

In this study, 48 patients were male and 29 patients were female (total: 77 patients). The average age of the survivors and non-survivors was 28.7 and 31.3 years, respectively. All cases (100%) of ALP poisoning were intentional, with the goal of committing suicide. The main predictive variables of mortality from ALP poisoning were blood pressure, blood pH, and time elapsed from consumption to treatment.

CONCLUSIONS

The likelihood of mortality in patients with ALP poisoning can be predicted using blood pressure, blood pH, and time elapsed from consumption to treatment. These findings may help healthcare providers take more effective measures to treat patients with ALP poisoning.

Cardiotoxic Effects of Raw Opium

While opioid drug toxicity and side effects of long-term opioid use during medical care are well studied, there is little information regarding effects of ingestion of raw opium. Characterization of the effects to a particular alkaloid is difficult since raw opium contains a number of alkaloids. Here, we present a case of poisoning due to ingestion of raw opium leading to severe myocardial suppression.

Reversible Myocardial Injury and Intraventricular Thrombus Associated with Aluminium Phosphide Poisoning

Aluminium phosphide (ALP) is widely used as a fumigant pesticide. In case of ALP poisoning, it is responsible for myocardial dysfunction, related to toxic myocarditis, and hemodynamic disorders. We report a case of a 28-year-old female who had intentionally ingested ALP and was admitted with cardiogenic shock. The transthoracic echocardiography (TTE) at the time of admission showed severe global myocardial hypokinesia with the presence of a giant left ventricular thrombus. Cardiovascular magnetic resonance (CMR) revealed extensive toxic myocarditis with a left ventricular systolic dysfunction. All cardiac lesions were reversible after symptomatic treatment, within 6 months. We aim, by reporting this case, to evidence the complete reversibility of cardiac injury due to aluminium phosphide poisoning documented by transthoracic echocardiography and cardiovascular magnetic resonance.

Therapeutic role of hyperinsulinemia/euglycemia in aluminum phosphide poisoning

BACKGROUND

Different protocols have been suggested to treat aluminum phosphide (ALP) poisoning. We aimed to evaluate the possible therapeutic effect of hyperinsulinemia/euglycemia (HIE) in treatment of ALP poisoning.

METHODS

In a prospective interventional study, a total of 88 ALP-poisoned patients were included and assigned into HIE group undergoing glucose/insulin/potassium (GIK) protocol and a control group that was managed by routine conventional treatments. The 2 groups were then compared regarding the signs and symptoms of toxicity and their progression, development of complications, and final outcome to detect the possible effect of GIK protocol on the patients' course of toxicity and outcome.

RESULTS

The 2 groups were similar in terms of demographic characteristics and on-arrival vital signs and lab tests. Using GIK protocol resulted in significantly longer hospital stays (24 vs 60 hours; P < 0.001) and better outcomes (72.7% vs 50% mortality; P = 0.03). Regression analysis showed that GIK duration was an independent variable that could prognosticate mortality (odds ratio [95% confidence interval] = 1.045 [1.004,1.087]). The risk of mortality decreased by 4.5% each hour after initiation of GIK.

CONCLUSION

GIK protocol improves the outcome of ALP poisoning and increases the length of hospital stay.

Subendocardial infarction in a young survivor of aluminium phosphide poisoning

Aluminium phosphide is a solid fumigant pesticide and has systemic toxicity due to liberation of phosphine gas. We report a case of aluminium phosphide poisoning with systemic toxicity in a 16-year-old patient who developed previously undocumented complication of subendocardial infarction, with characteristic electrocardiographic changes reverting back to normal after a period of 10 weeks, even though the patient had clinical recovery much earlier. Human & Experimental Toxicology ( 2007) 26, 457—460

Occupational exposure to aluminium phosphide and phosphine gas? A suspected case report and review of the literature

The manufacture and application of aluminium phosphide fumigants pose risks of inhalation exposure to phosphine gas. This article presents a case report of suspected inhalation exposure to phosphine gas in a manufacturing facility for aluminium phosphide fumigants, which was associated with acute dyspnoea, hypotension, bradycardia and other signs of intoxication. These symptoms resolved within several hours after removal from exposure. A review of the data on human exposures to phosphide fumigants identifies both pesticide applicators and individuals in the vicinity of application to be at risk of accidental exposure and injury from phosphine inhalation. More recent reports have identified risks of phosphine gas inhalation in association with the clandestine production of methamphetamine. Toxicodynamic effects of phosphine result from the inhibition of cytochrome c oxidase and subsequent generation of reactive oxygen species. There remain unanswered questions relating to the toxicokinetics of phosphine, as well as the assessment of human exposure utilizing biomarkers. As initial signs and symptoms of intoxication from phosphine gas may be nonspecific and transient, there is a need for improved recognition of the potential hazards associated with phosphide fumigants and phosphine gas.

Aluminum Phosphide Poisoning-Related Deaths in Tehran, Iran, 2006 to 2013

Metal phosphides such as aluminum phosphide are potent insecticides. This highly toxic substance is used for rice and other grains protection in Iran. Due to its high toxicity potential and easy availability, it is widely used as a suicide poison. This substance has no effective antidote and the incidence of deaths due to its poisoning is increasing day by day in Iran. The present study was conducted to show the increasing incidence of fatal aluminum phosphide poisoning and its toxicological and forensic aspects in an 8-year study, 2006 to 2013. Autopsy sheets were reviewed and cases with the history of aluminum phosphide poisoning were selected. Toxicological analysis results, demographic and necroscopic examination findings were studied. A total of 51.8% of studied cases were female. Most of the cases were between 10 and 40 years old. The manner of death was self-poisoning in 85% of cases. Morphine, ethanol, and amitriptyline were the most common additional drugs detected in toxicological analysis. The incidence of fatal aluminum phosphide poisoning cases referred for phosphine analysis was 5.22 and 37.02 per million of population of Tehran in 2006 and 2013, respectively. The results of this study showed that in spite of ban and restrictions, there was a dramatic increase in the incidence of fatal aluminum phosphide poisoning in Tehran from 2006 to 2013. Safety alert should be highlighted in training program for all population groups about the toxic effects of aluminum phosphide tablets.

Management of celphos poisoning with a novel intervention: A ray of hope in the darkest of clouds

Context:

Celphos poisoning is one the most common and lethal poisonings with no antidote available till now.

Aims:

To evaluate the effectiveness of new treatment regimens and interventions in reduction of mortality from the fatal effects of celphos poisoning.

Settings and Design:

A profile of 33 patients, who got admitted in Intensive Care Unit (ICU) of our institute with alleged intake of celphos pellets, was studied.

Materials and Methods:

In all the 33 patients with alleged celphos poisoning, extensive gastric lavage was done with a mixture of coconut oil and sodium bicarbonate solution. Strict monitoring, both invasive and non-invasive, was done and symptomatic/supportive treatment was carried out on a patient to patient basis.

Statistical Analysis:

At the end of the study, all the data were compiled systematically and statistical analysis was carried out using the non-parametric tests and value of P<0.05 was considered significant.

Results:

Majority of the patients out of the total 33 were young with mean age of 21.86±4.92 and had good educational level. Most of the patients presented clinically with cardiovascular signs and symptoms (58%), followed by respiratory distress (15%) and little higher incidence of multi-organ symptomatology (18%). The mean stay of the patients in ICU was 5.84±1.86 days and the survival rate was 42%.

Conclusions:

With the treatment regimen we have formulated, we were able to save 42% of our patients and recommend the use of this regimen by all the intensivists and physicians.

A case of accidental fatal aluminum phosphide poisoning involving humans and dogs

Aluminum phosphide is one of the commonest poisons encountered in agricultural areas, and manner of death in the victims is often suicidal and rarely homicidal or accidental. This paper presents an unusual case, where two humans (owner and housemaid) and eight dogs were found dead in the morning hours inside a room of a house, used as shelter for stray dogs. There was allegation by the son of the owner that his father had been killed. Crime scene visit by forensic pathologists helped to collect vital evidence. Autopsies of both the human victims and the dogs were conducted. Toxicological analysis of viscera, vomitus, leftover food, and chemical container at the crime scene tested positive for aluminum phosphide. The cause of death in both humans and dogs was aluminum phosphide poisoning. Investigation by police and the forensic approach to the case helped in ascertaining the manner of death, which was accidental.

Inhalation of phosphine gas following a fire associated with fumigation of processed pistachio nuts

On December 10, 2009, a fumigation stack containing aluminum phosphide became soaked with rain water and caught fire at a pistachio processing plant in Kern County, California. Untrained plant personnel responding to the fire had exposure to pyrolysis by-products, particulates, and extinguisher ingredients. Ten workers taken for medical evaluation had respiratory and nonspecific systemic symptoms consistent with exposure to phosphine gas. Six of the 10 workers had respiratory distress, indicated by chest pain, shortness of breath, elevated respiratory rate, or decreased oxygen saturation. Recommendations are made for the management of similar illnesses and prevention of similar exposures.

Aluminium phosphide-induced leukopenia

Acute intoxication from the pesticide aluminium phosphide is a relatively rare, life-threatening condition in which cardiovascular decompensation is the most feared problem. We report the case of a patient exposed to aluminium phosphide-liberated phosphine gas. It resulted in the development of a gastroenteritis-like syndrome accompanied by severe reduction in white blood cell numbers as an early and prominent manifestation. By affecting important physiological processes such as mitochondrial function and reactive oxygen species homeostasis, phosphine could cause severe toxicity. After presenting the characteristics of certain leucocyte subpopulations we provide the current molecular understanding of the observed leukopenia which in part seems paradoxical.

A rare case of homicidal insecticide (organochloro compound) poisoning by intraperitoneal injection

We report a case of a 52-year-old businessman who was allegedly injected with organochloro compound (OC) in his abdomen by his business rivals by means of a surgical needle and a syringe. Homicide by OC injection via an intraperitoneal route has not been reported in the literature. Postmortem findings along with the toxicology report have been discussed particularly in view of the mode of poison administration with a review of literature.

Aluminium phosphide poisoning and oxidative stress: serum biomarker assessment

According to previous animal studies, aluminium phosphides (AlPs) may induce oxidative stress leading to generation of free radicals and alteration in antioxidant defense system. This study was conducted to evaluate the existence and degree of oxidative stress in patients with acute AlP ingestion. A total of 44 acute AlP ingested patients as well as 44 age- and sex-matched controls were included. All patients had acute poisoning symptoms with AlP at the time of presentation and had blood samples analyzed for lipid peroxidation, total antioxidant capacity and total thiol. Our findings showed that there is a significant increase in lipid peroxidation in AlP ingested group along with a reduction in total antioxidant capacity and total thiols groups. These clinical data confirm previous experimental models that showed AlP exposure might significantly augment lipoperoxidative damage with simultaneous alterations in the antioxidant defense system. Hence, our findings might justify use of antioxidants in treatment of acute AlP poisoning which needs to be clarified by additional clinical trials.

A systematic review of aluminium phosphide poisoning

Every year, about 300,000 people die because of pesticide poisoning worldwide. The most common pesticide agents are organophosphates and phosphides, aluminium phosphide (AlP) in particular. AlP is known as a suicide poison that can easily be bought and has no effective antidote. Its toxicity results from the release of phosphine gas as the tablet gets into contact with moisture. Phosphine gas primarily affects the heart, lungs, gastrointestinal tract, and kidneys. Poisoning signs and symptoms include nausea, vomiting, restlessness, abdominal pain, palpitation, refractory shock, cardiac arrhythmias, pulmonary oedema, dyspnoea, cyanosis, and sensory alterations. Diagnosis is based on clinical suspicion, positive silver nitrate paper test to phosphine, and gastric aspirate and viscera biochemistry. Treatment includes early gastric lavage with potassium permanganate or a combination with coconut oil and sodium bicarbonate, administration of charcoal, and palliative care. Specific therapy includes intravenous magnesium sulphate and oral coconut oil. Moreover, acidosis can be treated with early intravenous administration of sodium bicarbonate, cardiogenic shock with fluid, vasopresor, and refractory cardiogenic shock with intra-aortic baloon pump or digoxin. Trimetazidine may also have a useful role in the treatment, because it can stop ventricular ectopic beats and bigeminy and preserve oxidative metabolism. This article reviews the epidemiological, toxicological, and clinical/pathological aspects of AlP poisoning and its management.

Electrocardiographic findings and cardiac manifestations in acute aluminum phosphide poisoning

Aluminium phosphide (AlP) poisoning has a high mortality due to cardiovascular involvement. In this study, we evaluated the frequency of cardiac manifestations and electrocardiographic (ECG) findings in 20 patients with acute AlP poisoning, who were admitted to the intensive care unit (ICU) in Tehran, Iran, over a period of 6 months (between October 2008 and April 2009). The sex, age, cause and manner of ingestion, number of ingested AlP tablets, cardiac and ECG manifestations, creatine phosphokinase (CPK), CPK-myocardial band (CPK-mb) and troponin-T (TnT) were extracted from the patients' files. All data were analysed with Statistical Package for the Social Sciences (SPSS) software. The majority (60%) of patients were male. The mean age was 27 ± 8.7 years. The mortality rate was 40%. In all of the patients, the cause of poisoning was intentional suicide and ingestion was the route of exposure. The mean number of ingested AlP tablets per patient was 2.2 ± 1.1. The average time interval between admission and cardiovascular manifestations or ECG findings was 168.8 ± 116.2 min. The range of systolic (SBP) and diastolic blood pressure was 60-130 mmHg and 40-70 mmHg, respectively. Dysrhythmia was observed in nine (45%) cases. Elevation of the ST segment was seen in nine cases (45%). Seven patients (35%) had prolonged QTc intervals. Bundle branch block (BBB) was observed in four (20%) patients. In nine (45%) patients, the serum cardiac TnT qualitative assay was positive. There were no significant differences between normal and abnormal ECG groups according to sex, age, number and manner of ingested AlP tablets and SBP. There was a significant correlation between cardiac manifestations and ECG findings and TnT-positive results with mortality in acute AlP poisoning.

Managing aluminum phosphide poisonings

Aluminum phosphide (AlP) is a cheap, effective and commonly used pesticide. However, unfortunately, it is now one of the most common causes of poisoning among agricultural pesticides. It liberates lethal phosphine gas when it comes in contact either with atmospheric moisture or with hydrochloric acid in the stomach. The mechanism of toxicity includes cellular hypoxia due to the effect on mitochondria, inhibition of cytochrome C oxidase and formation of highly reactive hydroxyl radicals. The signs and symptoms are nonspecific and instantaneous. The toxicity of AlP particularly affects the cardiac and vascular tissues, which manifest as profound and refractory hypotension, congestive heart failure and electrocardiographic abnormalities. The diagnosis of AlP usually depends on clinical suspicion or history, but can be made easily by the simple silver nitrate test on gastric content or on breath. Due to no known specific antidote, management remains primarily supportive care. Early arrival, resuscitation, diagnosis, decrease the exposure of poison (by gastric lavage with KMnO(4), coconut oil), intensive monitoring and supportive therapy may result in good outcome. Prompt and adequate cardiovascular support is important and core in the management to attain adequate tissue perfusion, oxygenation and physiologic metabolic milieu compatible with life until the tissue poison levels are reduced and spontaneous circulation is restored. In most of the studies, poor prognostic factors were presence of acidosis and shock. The overall outcome improved in the last decade due to better and advanced intensive care management.

Blood levels of methemoglobin in patients with aluminum phosphide poisoning and its correlation with patient's outcome

Although methemoglobinemia following aluminum phosphide (AlP) intoxication has been reported, probable effect of blood level of methemoglobin (Met-Hb) on outcome of AlP-poisoned patients has not yet been investigated. This study aimed to evaluate blood levels of methemoglobin in patients with AP intoxication and its correlation with patient's outcome. This prospective study was carried out at the Loghman-Hakim poison hospital from April 2009 to August 2009. All patients aged >12 years who had ingested AlP and were admitted at the hospital were enrolled in the study. Using the co-oximetry, blood Met-Hb level was measured at the time of admission and 24 h later if the patient survived. Forty-eight patients with AlP intoxication including 24 males were evaluated. Mean age of the patients was 25.5±9.5 years. There was significant association between blood level of Met-Hb at the time of admission and mortality (2.4%±7.1% in survivors versus 15.2%±13.5% in non-survivors, P<0.001). The same association was found at the 2nd day of admission (2.9%±8.2% in survivors versus 26.5%±9.9% in non-survivors, P=0.02). The present study found an association between blood level of Met-Hb and mortality in patients with AlP intoxication. Effect of administration of vitamin C and methylene blue on outcome of patients with AlP intoxication should be investigated in future studies.

Aluminium phosphide (tank pill) poisoning in the Transkei region of South Africa: a case report

About half a million people die each year as a result of various kinds of poisoning. The incidence of pesticide poisoning, which is high in developing countries, has doubled over the past 10 years. Aluminium phosphide is a deadly fumigant pesticide. A 21-year-old man committed suicide by ingesting aluminium phosphide, which he had available in his home. He had been charged with rape, and was to appear in court. Soon after ingestion, he told his grandmother about the suicide attempt. He was taken to a nearby hospital, where he was dead within an hour of arriving. The mechanism of action, symptoms and signs will be discussed in this report. The purpose of this case report is to highlight the problem of aluminium phosphide poisoning in the Transkei region of South Africa.

Unresponsive ventricular tachycardia associated with aluminum phosphide poisoning

Inhalation or ingestion of aluminum phosphide (AP) generates phosphine gas on exposure to moisture, which, in turn, produces widespread organ toxicity primarily involving the lungs, heart, liver, and kidneys. Cardiac manifestations of AP poisoning include toxic myocarditis, refractory heart failure, bradyarrhythmias, and tachyarrhythmias including ventricular tachycardia (VT). A 19-year-old depressed male farm worker ingested ten 500-mg tablets of Celphos in a suicide attempt. Each Celphos tablet contains 56% AP. Over the course of 10 hours, the patient developed heart failure and respiratory failure associated with a rise in serum troponin level to 12.7 ng/mL. Serum electrolytes (including magnesium) and serum creatinine levels were normal throughout. His course was further complicated by acidemia and hypotension. These hemodynamic and metabolic abnormalities were initially corrected by assisted ventilation and continuous veno-venous hemofiltration. However, he developed hemodynamically stable sustained monomorphic VT, which proved unresponsive to treatment with intravenous magnesium sulfate and intravenous amiodarone therapy. After a decline in blood pressure, 6 attempts at electrocardioversion failed to restore sinus rhythm, and he died. Postmortem histologic examination of myocardium showed contraction band necrosis, early coagulation necrosis, edema, hemorrhage, and pyknosis of cardiac myocyte nuclei. Ventricular tachycardia associated with AP poisoning has been successfully treated with magnesium sulfate, amiodarone, and electrocardioversion. This case report documents failure of all 3 of these therapeutic modalities.

Phosphine intoxication following oral exposure of horses to aluminum phosphide-treated feed

CASE DESCRIPTION

66 horses were potentially exposed to phosphine (a gas) 14 hours after being fed a pelleted ration treated with aluminum phosphide.

CLINICAL FINDINGS

28 horses had clinical signs of profuse sweating, tachycardia, tachypnea, pyrexia, ataxia, seizures, and widespread muscle tremors. Clinically relevant laboratory findings included hypoglycemia and high plasma concentrations of lactate and ammonia and activities of gamma-glutamyl transpeptidase, aspartate aminotransferase, and alkaline phosphatase. At least 4 horses had signs consistent with hepatic encephalopathy. Necropsy findings included petechial and ecchymotic hemorrhages in multiple organs, widespread vascular congestion, hepatic lipidosis, and neuronal necrosis in the brain. Phosphine was detected in the stomachs of the 3 horses tested.

TREATMENT AND OUTCOME

On the farm, horses were treated with gastric lavage followed by administration of di-tri-octahedral smectite, atropine, fluids, and sedatives. Six horses were hospitalized, and lactated Ringer's solution and flunixin meglumine were administered IV. Additionally, 10% dextrose, corn syrup, and di-tri-octahedral smectite were administered PO. Twenty-seven horses died within 2 days after exposure. Two survivors (1 without clinical signs of toxicosis) made a complete recovery.

CLINICAL RELEVANCE

Progression of clinical signs in affected horses in this report was rapid, with few treatment options available, leading to a high case fatality rate. Fumigation with aluminum phosphide is commonly performed to eliminate weevils and other insects from stored grains. When appropriate precautions are used during fumigation, risk to livestock is typically minimal.

Intra-aortic balloon pump in toxic myocarditis due to aluminum phosphide poisoning

INTRODUCTION

Aluminum phosphide (ALP) is a pesticide that is highly toxic. It is a mitochondrial toxin that causes death by cardiac and metabolic toxicity. The most ominous effect is cardiac toxicity, which may range from minor electrocardiographic abnormalities to severe depression of cardiac contractility secondary to toxic myocarditis. There is no documented report of the use of Intra-aortic Balloon Pump (IABP) for toxic myocarditis from ALP poisoning, although it has been used effectively for toxic myocarditis due to other toxins.

CASE REPORT

We are reporting a young female who presented with ALP poisoning, in cardiogenic shock due to myocarditis. We used an IABP for cardio-circulatory support until the effects of ALP resolved. She is the only reported survivor of ALP poisoning, presenting with cardiogenic shock.

DISCUSSION

Several reports describe the use of IABP for cardiogenic shock due to toxic myocarditis. There is no report in the medical literature using IABP for cardiogenic shock caused by ALP toxin-induced myocarditis. Our patient presented with cardiocirculatory shock, necessitating the use of inotropes and mechanical ventilation. As she did not improve despite ventilation and maximal doses of inotropes, IABP was used for cardio-circulatory support until the effects of ALP resolved.

Hyperglycemia in acute aluminum phosphide poisoning as a potential prognostic factor

Aluminum phosphide (AlP) is a solid fumigant widely used in Iran as a grain preservative. When reacted with water or acids, AIP produces phosphine gas, a mitochondrial poison that interferes with oxidative phosphorylation and protein synthesis. Poisoning by AIP is one of the most important causes of fatal chemical toxicity in Iran. There are few studies in the medical literature addressing prognostic factors associated with AlP poisoning. In this prospective study conducted across a 14-month period commencing on 21st March 2006, we enrolled all patients admitted to the ICU of Loghman-Hakim Hospital Poison Center (Tehran, Iran) with AIP poisoning, no history of diabetes mellitus diagnosed before hospitalization, and normal body mass index. We recorded patient-specific demographic information, blood glucose level on presentation (before treatment), arterial blood gas (ABG) analysis, time elapsed between ingestion and presentation, ingested dose, duration of intensive care admission, and outcome data related to each presentation. We enrolled the group of patients who survived the intoxication as a control group and compared their blood glucose levels with those who died because of AlP poisoning. Data were analyzed by Statistical Product and Service Solutions (SPSS) software (Version 12; Chicago, Ilinois, USA) using logistic regression, Pearson correlation coefficient and Student's t-test. P values of 0.05 or less were considered as the statistical significant levels. Forty-five patients (21 women and 24 men) with acute AlP poisoning were included in the study. The mean age was 27.3 +/- 11.5 years (range: 14-62 years). Thirteen patients survived (29%) and 32 expired (71%). AlP poisoning followed deliberate ingestion in all patients. The time elapsed between ingestion and arrival at the hospital was 3.2 +/- 0.4 h. There was no significant difference between survived and non-survived groups according to age, gender, and time to treatment. However, the difference between mean blood glucose levels in survived (143.4 +/- 13.7 mg/dL) and non-survived (222.6 +/- 20 mg/dL) cases was statistically significant (P = 0.021). There was no significant correlation between blood glucose level and time to treatment, age, gender, pH, HCO3 concentration, and ingested dose. Twenty-three (71.9%) of non-survived and four (30.8%) of survived patients had a blood glucose level greater than 140 mg/dL. After adjusting according to age, gender, ingested dose, pH and HCO3 concentration The odds ratio for hyperglycemia as a risk factor for death was 5.7 (CI of 1.4-23.4). In our study, patients who succumbed to AIP poisoning had significantly higher mean blood glucose levels than those who survived. This correlation of hyperglycemic effect and mortality suggests that it may be useful in guiding risk assessment and treatment of AIP poisoning. Management of hyperglycemia may have a useful role in treatment of these patients by allowing increased entrance of glucose into cells and reducing oxygen consumption.

Unintentional poisoning by phosphine released from aluminum phosphide

Aluminum phosphide as a releaser of phosphine gas is used as a grain preservative. In this case report, we describe an accidental severe poisoning in a 35-year-old woman, her 18-year-old daughter, and 6-year-old son caused by inhalation of phosphine gas released from 20 tablets of aluminum phosphide stored in 15 rice bags. The boy died 2 days after exposure before admission to hospital and any special treatment, but the others were admitted 48 h after exposure. They had signs and symptoms of severe toxicity, and their clinical course included metabolic acidosis, electrocardiographic changes, and hypotension. They were treated by intravenous administration of sodium bicarbonate, magnesium sulfate, and calcium gluconate. The patients were discharged after 3 days and followed up for 1 week after discharge. Rapid absorption of phosphine by inhalation, induction of hyperglycemia, and surviving of patients are interesting issues of this case report.

Acute pancreatitis: a lesser-known complication of aluminum phosphide poisoning

There have been no case reports on aluminum phosphide-induced pancreatitis in the literature available. In this report, we present the case of a young man who developed acute pancreatitis and probably acute myocarditis following ingestion of aluminum phosphide pellets in the absence of the usual risk factors and after exclusion of other possible causes of pancreatitis. In the absence of re-challenge, we put forth the probable causative association of pancreatitis with aluminum phosphide or phosphine gas, its active pesticidal component.

A gas chromatographic analysis of phosphine in biological material in a case of suicide

In a suicide committed using aluminium phosphide (AlP) the liberated toxic phosphine gas was detected in post-mortem specimens using a headspace gas chromatographic procedure with a nitrogen-phosphorous detector (HS-GC/NPD). At autopsy a direct sampling into airtight headspace vials for a later analysis is recommended. AlP has to be considered a potent pesticide and its use and availability should be restricted as much as possible.

Reversible myocardial injury associated with aluminum phosphide poisoning

BACKGROUND

Aluminum phosphide poisoning has high mortality resulting from cardiac impairment and hemodynamic disorders. We report two cases of aluminum phosphide associated with reversible myocardial injury.

CASES REPORTS

A 19-year-old woman and a 28-year-old man were admitted to hospital following ingestion of aluminum phosphide. The clinical course was characterized by the development of a shock syndrome requiring the use of vasoactive amines in the woman. However, the arterial hypotension in the man was improved by fluid filling and vasoactive drugs. The myocardial injury was objectively documented in both cases. The electrocardiogram showed ST-segment elevations and diffusely abnormal repolarization. The plasma concentrations of cardiac enzymes were elevated. In the second case, echocardiography showed similar myocardial involvement with left ventricular hypokinesis (left ventricle ejection fraction 30%). In both cases, there was progressive improvement in hemodynamic status, cardiac traces, and biochemical values. A simultaneous improvement was observed in echocardiogram of the second case (left ventricle ejection fraction increased to 50%).

CONCLUSION

Reversible myocardial injury following aluminum phosphide poisoning has been described in few cases. We objectively documented progressive clinical and electrical improvement in two cases.

[Severity factors of aluminium phosphide poisoning (Phostoxin)]

OBJECTIVES

To determine characteristics of acute aluminum phosphide poisoning (AAlPP) and to evaluate its severity factors.

DESIGN STUDY

Retrospective cohort study.

PATIENTS AND METHODS

Consecutive cases of AAlPP admitted in medical ICU (Hospital Avicenne, Rabat, Morocco) between January 1992 and December 2002 were studied. AAlPP was identified by history, symptoms and toxicological results. Almost 50 parameters have been collected and compared between survivors and non-survivors groups. Data were analyzed using Fisher exact test and Mann-Whitney test.

RESULTS

Twenty-eight patients were enrolled: 17 female and 11 male, average age = 24+/-11 years, SAPS II = 24.4+/-14.5. The ingested dose was 3.3+/-1.8 g. The self-poisoning was observed in 27 cases and delay before hospital admission was 11+/-13 hours. Mean Glasgow coma scale was 14+/-2. Shock was found in 22 (79%) cases. Average pH was 7.1+/-0.4 and bicarbonate concentration was 16.3+/-8.8 mmol/l. The ECG abnormalities were noted in 20 (72%) cases. The average mortality rate was 61%. The prognostic factors were SAPS II (p = 0.031), Apache II (p = 0.037), shock (p = 0.022), ECG abnormalities (p = 0.05), use of vasoactive drugs (p = 0.05) and use of mechanical ventilation (p = 0.003).

CONCLUSION

AAlPP induced a significantly high mortality and haemodynamic disturbances were a risk factor of poor outcome.

Epidemiology of hydrogen phosphide exposures in humans reported to the poison center in Mainz, Germany, 1983-2003

BACKGROUND

Poisonings with rodenticides containing hydrogen phosphide-releasing compounds may lead to deleterious organ dysfunction and death. Since data of hydrogen phosphide poisonings is limited to case reports/series, this study was intended to elucidate hydrogen phosphide poisonings based on a 20-year data collection.

METHODS

Explorative data analysis of the Poison Center Mainz database looking for route of exposure, symptoms, and severity using the Poisoning Severity Score.

RESULTS

From 1983-2003, 188 hydrogen phosphide poisonings were reported. Sixty-five percent of these were unintentional residential, 28% attempts to commit suicide (intentional), 5% occupational, and 2% undetermined. In the majority of intentional poisonings the poison was ingested, whereas in unintentional poisoning of adults inhalation exposure dominated, caused by inappropriate self-protection from the released hydrogen phosphide gas during usage. Frequently observed symptoms in unintentional poisonings were nausea, vomiting, pain, coughing, and dizziness with no further worsening of symptoms. In intentional poisonings frequent symptoms were vomiting, somnolence, seizures, coma, and shock with two initially fatal poisonings. Follow-up on these cases showed a significant worsening of symptoms and a two-fold increase in fatal poisonings.

CONCLUSION

Route of exposure, severity of symptoms, and the necessary treatment differs substantially between unintentional and intentional poisonings. In this study, two initially symptomatic intentional poisonings were later reported fatal. Careful monitoring is recommended in symptomatic intentional poisonings.

Successful treatment of acute aluminium phosphide poisoning: possible benefit of coconut oil

Aluminium phosphide is used to control rodents and pests in grain storage facilities. It produces phosphine gas, which is a mitochondrial poison. Unfortunately, there is no known antidote for aluminium phosphide intoxication, but our recent experience with a case showed that rapid prevention of absorption by coconut oil might be helpful. In the present case, we used the same protocol in a 28-year-old man who had ingested a lethal amount (12 g) of aluminium phosphide with suicidal intent and was admitted to hospital approximately 6 hours postingestion. The patient had signs and symptoms of severe toxicity, and his clinical course included metabolic acidosis and liver dysfunction. Treatment consisted of gastric lavage with potassium permanganate solution, oral administration of charcoal and sorbitol suspension, intravenous administration of sodium bicarbonate, magnesium sulphate and calcium gluconate, and oral administration of sodium bicarbonate and coconut oil. Conservative and supportive therapy in the Intensive Care Unit was also provided. The patient survived following rapid treatment and supportive care. It is concluded that coconut oil has a positive clinical significance and can be added to the treatment protocol of acute aluminium phosphide poisoning in humans.