Exploring research gaps and trends in the management of acute phosphide poisoning: a systematic review.

Metal phosphides are highly toxic pesticides that result in high morbidities and mortalities worldwide. This systematic review included 350 studies that fulfilled the eligibility criteria. There were significant rising trends of studies on acute aluminum phosphide (AlP) and zinc phosphide (Zn3P2) poisoning (p-values = <.001), pointing to an increased number of phosphide-intoxicated patients. Acute AlP poisoning studies represented 81%, 89.3%, and 97.7% of all descriptive, analytical, and experimental interventional studies included in this review, respectively. High AlP poisoning mortality explains great research interest in AlP poisoning. Thus, after 2016, nearly half (49.7%) of studies on acute AlP poisoning were issued. Also, 78.82% of experimental interventional studies on AlP poisoning were published after 2016. The trends of in-vitro, animal, and clinical studies on AlP poisoning significantly increased with p-values equal to .021, <.001, and <.001, respectively. Seventy-nine treatment modalities for acute AlP poisoning were pooled from 124 studies; 39 management-related case reports, 12 in-vitro studies, 39 animal studies, and 34 clinical studies. All therapeutic modalities were summarized to formulate an integrated and comprehensive overview. For clinicians, therapeutic modalities significantly decreased mortality of acute AlP poisoning in clinical trials included extracorporeal membrane oxygenation (ECMO), N-acetyl cysteine (NAC), vitamin E, glucose-insulin-potassium (GIK) infusion, fresh packed RBCs infusion, and GIT decontamination using oils. However, meta-analyses are needed to provide solid evidence regarding their efficacies. To date, there is no effective antidote nor evidence-based standardized protocol for managing acute AlP poisoning. This article outlined the potential research gaps in phosphide poisoning that might promote and direct future medical research in this context.

Clinical manifestations and treatment management of hospitalized patients with zinc phosphide poisoning, Mazandaran Province, Northern Iran.

BACKGROUND: Zinc phosphide (ZnP) is a dark gray crystalline compound used as a rodenticide against rodents such as mice. ZnP poisoning may be accidental or suicidal. The aim of this study was to investigate the clinical manifestations and treatment management of hospitalized patients with ZnP poisoning in Mazandaran Province, northern Iran. METHODS: Between 2013 and 2017, a cross-sectional study was performed on hospitalized patients with ZnP poisoning who were referred to two training hospitals in Mazandaran Province, northern Iran. RESULTS: A total of 127 patients participated in this trial, including 71 (55.9%) men and 56 (44.1%) women. The patients' average (standard deviation) age was 25.5 (±16.82) years, and it took 2.18 (±2.23) hours to refer them to the hospital. There were 42 (33%) cases with less than one package, 9 (7%) cases with several packages, and 76 (60%) cases with no particular usage. CONCLUSIONS: This study has shown that ZnP poisoning may be asymptomatic initially or with mild clinical symptoms that may gradually worsen. Therefore, hospitalization and obtaining a history and a careful physical examination should be considered.

Rodenticide Poisoning.

How to cite this article: D'Silva C, Krishna B. Rodenticide Poisoning. Indian J Crit Care Med 2019;23(Suppl 4):S272-S277.

Suicidal Zinc Phosphide Poisoning Unmasking Brugada Syndrome and Triggering Near Fatal Ventricular Arrhythmia.

Brugada syndrome (BrS) is an inherited channelopathy associated with increased incidence of ventricular arrhythmias and has many acquired triggers. Zinc phosphide (ZnP) is a rodenticide and is commonly implicated in suicidal poison ingestion. ZnP poisoning can cause myocardial toxicity and death. We report a case of ZnP poisoning that triggered a type I Brugada pattern and ventricular fibrillation in a 67-year-old male. He had no other features of toxicity and recovered later. As metal phosphide is the commonest toxin involved in suicidal poisoning in India and BrS being endemic here, this case highlights an important clinical problem.

Zn3P2-Zn3As2 solid solution nanowires.

Semiconductor alloy nanowires (NWs) have recently attracted considerable attention for applications in optoelectronic nanodevices because of many notable properties, including band gap tunability. Zinc phosphide (Zn3P2) and zinc arsenide (Zn3As2) belong to a unique pseudocubic tetragonal system, but their solid solution has rarely been studied. Here In this study, we synthesized composition-tuned Zn3(P1-xAsx)2 NWs with different crystal structures by controlling the growth conditions during chemical vapor deposition. A first type of synthesized NWs were single-crystalline and grew uniformly along the [110] direction (in a cubic unit cell) over the entire compositional range (0 ≤ x ≤ 1) explored. The use of an indium source enabled the growth of a second type of NWs, with remarkable cubic-hexagonal polytypic twinned superlattice and bicrystalline structures. The growth direction of the Zn3P2 and Zn3As2 NWs was also switched to [111] and [112], respectively. These structural changes are attributable to the Zn-depleted indium catalytic nanoparticles which favor the growth of hexagonal phases. The formation of a solid solution at all compositions allowed the continuous tuning of the band gap (1.0-1.5 eV). Photocurrent measurements were performed on individual NWs by fabricating photodetector devices; the single-crystalline NWs with [110] growth direction exhibit a higher photoconversion efficiency compared to the twinned crystalline NWs with [111] or [112] growth direction.

Successful management of zinc phosphide poisoning.

Zinc phosphide (Zn2P3) rodenticide, is generally misused intentionally for suicidal purpose in Iran. For many years, scientists believe that liberation of phosphine (PH3) on contact with acidic content of the stomach is responsible for clinical presentations. However, relatively long time interval between ingestion of Zn2P3 and presentation of its systemic toxicity, and progression of acute liver failure could not be explained by the current opinion. Hence, an innovative theory intended that phosphonium, as an intermediate product will create and pass through the stomach, which then will reduce to produce PH3in the luminal tract. Here, we present a case of massive Zn2P3 poisoning. In our case, we used repeated doses of castor oil to induce bowel movement with an aim of removing unabsorbed toxin, which was proved by radiography. Interestingly, the patient presents only mild symptoms of toxicity such as transient metabolic acidosis and hepatic dysfunction.

In vivo treatment of zinc phosphide poisoning by administration of mesoporous silica nanoparticles as an effective antidote agent.

Mesoporous silica nanoparticles (MSNs) are highly advanced engineered particles with increased surface area and extreme adsorption capacity for various molecules. Herein, two types of MSNs were synthesized and applied as adsorbents for phosphine gas. One was without functional groups (MSN), and the other was post-modified with boric acid (MSN-BA). The structures of MSN and boric acid-modified MSN with high surface areas of about 1025 and 650 m2/g, respectively, were defined. MSN was found to have particles with sizes around 30 nm by transmission electron microscopy (TEM). In the present study, MSNs were used as an antidote to phosphorus poisoning, and zinc phosphide (phosphorus) powder was used as the toxic and lethal agent. In vivo analysis was carried out on rats to demonstrate the ability of MSNs to chemisorb phosphine gas. In the survival percentage assessment, Phos-poisoned animals were kept alive after treatment with MSNs, and the MSN-BA-treated group (dose of 5 mg/kg) was shown to have a 60 % survival rate. Blood serum analysis showed that MSNs have a high potential to alleviate organ blood damage, and serum biomarkers dropped sharply while phosphine-poisoned animals were treated with MSN-BA.

Refractory cardiogenic shock caused by zinc phosphide toxicity.

Zinc phosphide toxicity is a rare entity that presents most frequently among farmers in developing countries who use it as a rodenticide. The phosphine gas released after the ingestion inhibits cytochrome c oxidase, disrupting the mitochondrial physiology and oxidative phosphorylation and causing myocardial stunning. Here we present a case of a 20-year-old man who attempted suicide with zinc phosphide toxicity. Initially, he was hemodynamically stable with a normal ejection fraction; however, in a few hours, he deteriorated quickly and became hemodynamically unstable, with rapid deterioration of his ejection fraction to 20%. He was started on norepinephrine and then dobutamine; however, he had cardiac arrest from refractory cardiogenic shock despite resuscitative measures.

A Case of Zinc Phosphide-Induced Acute Fulminant Liver Failure.

The use of rodenticides such as zinc phosphate is common in tropical countries. However, it has a toxic effect on humans when consumed or absorbed accidentally or deliberately. Although the adverse effects often only last for a short period, acute or fulminant liver failure can occur in few patients. Because the chemicals can create a wide variety of symptoms, it is essential to investigate the progression of symptoms from mild to severe so that treatment protocols can be understood and patients can receive appropriate care. In this report, we detail a case of rodenticide poisoning in a middle-aged man who, initially, had only minor symptoms but ultimately developed fulminant liver failure. In this example, we discuss the case of a 40-year-old man who intentionally consumed 10 gm of rat poison (zinc phosphide (ZnP)) and reported to our department with a complaint of nausea and three episodes of vomiting. A neurological evaluation showed that the patient had a Glasgow Coma Scale score of 9/15 (Eye(E): 2; Motor(M): 4; Verbal(V): 3). Doll's eyes were present, and the patient's pupils were semi-dilated, sluggishly reacting to light. The plantars were bilateral extensor. In the subsequent four hours, the patient developed a deep coma. The patient's lack of awareness, coagulopathy, and abnormal liver enzyme values all pointed to acute fulminant liver failure. His condition improved with supportive therapy over a period of three weeks.

Radiopaque rodenticide.

BACKGROUND: Rodenticide poisoning is common in developing countries. Patients may be unwilling or unable to provide a history on presentation. CASE HISTORY: A 34-year-old man was referred to the emergency department three hours after the intentional ingestion of five packs of a black powdered rodenticide containing zinc phosphide. Radiopaque material was detected in the stomach on an abdominal radiograph. CONCLUSION: Abdominal radiography may be a useful tool in identifying the ingestion of metal phosphides when a history is not obtainable.

Zinc Phosphide Poisoning: From A to Z.

Zinc phosphide is a rodenticide that is used in agricultural, urban and industrial environments in México. After ingestion, it reacts with hydrochloric acid, hydrolyzing into phosphine. It causes cellular hypoxia via mitochondrial toxicity, resulting in multiple organ dysfunction and death. There is no antidote or specific treatment for zinc phosphide toxicity. We present the case of a 45-year-old female who ingested zinc phosphide with suicidal intent. On arrival at the emergency department, she had multisystemic disorders. Supportive care, decontamination and antidotal therapy were initiated. Subsequently, she evolved to clinical improvement with a resolution of the biochemical abnormalities of tissue hypoperfusion. She was discharged on day 7 without complications. In this review, we provide updated therapeutic options and discuss their specific pathophysiological basis.

N-Acetyl Cysteine in Rodenticide Poisoning: A Systematic Review and Meta-Analysis.

BACKGROUND: Treatment with N-Acetyl Cysteine (NAC) in rodenticide poisoning has not been well established due to mixed study results and insufficient evidence. This review aimed to summarize the clinical benefits of NAC in the management of rodenticide poisoning. METHODS: This review follows the PICOS framework and the PRISMA guidelines. Pub- Med/MEDLINE, Scopus, and the Cochrane library were searched to identify the published literature from inception to September 2020, and a reference search was performed for additional relevant studies. The English language studies addressing the use of NAC in rodenticide poisoning were considered for the review. We considered all experimental and observational studies due to the insufficient number of interventional studies. RESULTS: Ten studies (two RCTs, four observational, and four descriptive) out of 2,178 studies with 492 participants were considered for the review. Only six studies (two RCTs, one prospective, and three retrospective studies) reported recovery and mortality. Pooled results of RCTs (n=2) showed a significant recovery rate (Odds Ratio [OR]: 3.97; 95% Confidence Interval [CI]:1.69-9.30), whereas summary estimates of prospective and retrospective studies recorded a non-significant effect. Metaanalysis of RCTs (OR: 0.25; 95% CI: 0.11-0.59; n=2) and retrospective studies (OR: 0.34; 95% CI: 0.15-0.78; n=3) showed a significant reduction in mortality, whereas pooled analysis of prospective studies recorded a non-significant effect. A significant reduction in intubation or ventilation (OR: 0.25; 95% CI: 0.11-0.60; 2 RCTs) and a non-significant (P=0.41) difference in duration of hospitalization was observed with NAC when compared to the non-NAC treated group. The quality of the included studies appeared to be moderate to high. CONCLUSION: Our findings indicate that NAC showed better survival and lower mortality rate when compared to non-NAC treated group; hence NAC can be considered for the management of rodenticide poisoning.

Effects of background food on alternative grain uptake and zinc phosphide efficacy in wild house mice.

BACKGROUND: House mice (Mus musculus) cause significant, ongoing losses to grain crops in Australia, particularly during mouse plagues. Zinc phosphide (ZnP) coated grain is used for control, but with variable success. In a laboratory setting, we tested if mice would (i) switch from consumption of one grain type to another when presented with an alternative and (ii) consume ZnP-treated grains when presented as a choice with a different grain. RESULTS: Mice readily switched from their background grain to an alternative grain, preferring cereals (wheat or barley) over lentils. Mice readily consumed ZnP-coated barley grains. Their mortality rate was significantly higher (86%, n = 30) in the presence of a less-favoured grain (lentils) compared to their mortality rate (47%, n = 29; 53%, n = 30) in the presence of a more-favoured grain (wheat and barley, respectively). Mice died between 4 and 112 h (median = 18 h) after consuming one or more toxic grains. Independent analysis of ZnP-coated grains showed variable toxin loading indicating that consumption of a single grain would not guarantee intake of a lethal dose. There was also a strong and rapid behavioural aversion if mice did not consume a lethal dose on the first night. CONCLUSIONS: The registered dose rate of 25 g of ZnP/kg wheat (~1 mg of ZnP/grain) in Australia needs to be re-evaluated to determine what factors may be contributing to variation in efficacy. Further field research is also required to understand the complex association between ZnP dose, and quantity and quality of background food on efficacy of ZnP baits.

Cd3P2/Zn3P2 Core-Shell Nanocrystals: Synthesis and Optical Properties.

II-V semiconductor nanocrystals such as Cd3P2 and Zn3P2 have enormous potential as materials in next-generation optoelectronic devices requiring active optical properties across the visible and infrared range. To date, this potential has been unfulfilled due to their inherent instability with respect to air and moisture. Core-shell system Cd3P2/Zn3P2 is synthesized and studied from structural (morphology, crystallinity, shell diameter), chemical (composition of core, shell, and ligand sphere), and optical perspectives (absorbance, emission-steady state and time resolved, quantum yield, and air stability). The improvements achieved by coating with Zn3P2 are likely due to its identical crystal structure to Cd3P2 (tetragonal), highlighting the key role crystallographic concerns play in creating cutting edge core-shell NCs.

Rodenticide-induced acute liver failure - Uncommon presentation of commonly available poison.

Rodenticide or 'rat poison' is easily available in a predominantly agrarian economy such as India. Metal phosphides or yellow phosphorous are two common rodenticides. Acute liver failure caused by accidental or suicidal poisoning with rodenticides has been infrequently reported in literature. Liver transplantation offers the best chances of survival in severe intoxication. However, the availability of liver transplantation in resource-limited settings presents a challenge. N-acetyl cysteine has been successfully used in paracetamol poisoning. Its use in rodenticide-induced acute liver failure is not so well known. We report three cases of rodenticide-related acute liver failure, one of them being a pregnant lady. All three patients were given N-acetyl cysteine and two patients improved. It is possible that the administration of N-acetyl cysteine contributed to the improvement in these two.

Suicide attempt using zinc phosphide rodenticide: A case report and literature review.

The patients with a history of intentional or unintentional consumption of rodenticide compounds, especially ZnP, it is necessary to assess ABG and abdominal radiography.

Acute Pancreatitis Complicating Liver Transplantation in a Case of Fulminant Hepatic Failure Due to Yellow Phosphorus Poisoning.

INTRODUCTION: Yellow phosphorus (YP) is a general protoplasmic poison causing hepatic, cardiac, renal, and multiorgan failure. We report an unusual case of fulminant liver failure due to ratol (YP) poisoning complicated by acute pancreatitis postoperatively after liver transplantation. CASE REPORT: A 25-yr-old man presented with alleged consumption of approximately 7 gm of Ratol paste. Serum amylase and lipase levels were 880 and 2423, respectively, and CT imaging of pancreas was normal. He developed fulminant liver failure, fulfilling King's college criteria and an living donor liver transplantation was performed. Intraoperatively fat saponification was seen at the root of mesentery. On postoperative day (POD) 13, he developed incisional wound dehiscence and he underwent laparotomy with extensive slough removal from the lateral aspect of wound. On POD 21, wound showed evidence of burst abdomen. CT abdomen revealed inflamed tail of pancreas with peripancreatic fat stranding and an exploratory laparotomy was performed again. Intraoperatively, walled-off necrotic collection was seen in the tail of the pancreas and necrosectomy was carried out. All the aforementioned re-explorations were carried out under steroid immunosuppression. He was restarted on tacrolimus on POD27. Graft function and cholestatic biochemistry improved progressively, and he was discharged and is on regular follow-up. DISCUSSION: YP is very toxic with rapid absorption and gets accumulated in liver causing acute liver failure. Acute pancreatitis in a patient after liver transplantation for fulminant liver failure owing to Ratol poisoning has not been reported in published English literature. Although clinically relevant pancreatitis is rare in ratol poisoning, despite elevated pancreatic enzymes, it is prudent to meticulously image pancreas before embarking on liver transplantation. In those with pretransplant elevation of pancreatic enzymes, it is desirable to follow up the enzyme values postoperatively.

Forensic implications of pituitary macroadenoma: An autopsy case report.

Pituitary adenomas are the most common tumours of the sellar region. Functional pituitary adenomas are related with immense assorted variety in their endocrine manifestations secondary to hypo or hyperfunction of the pituitary gland and mass impact. They can have a slow but severe impact on vision due to compression of the optic nerves, optic chiasm and cavernous sinus. Hereby, we discuss a case of a 29-year-old female patient who presented to the emergency with an alleged history of chest pain after ingestion of rat poison (zinc phosphide) in an attempt to commit suicide. Autopsy finding revealed a large mass that was present in the pituitary fossa impinging onto the optic chiasma. On further inquiry of the law enforcing agencies, it was found that the patient was undergoing treatment for psychiatric illness, and she had also complained of vision loss for the past few months. The parents of the deceased lodged a case of homicide by the husband. This case demonstrates the psycho-social and forensic implications of a pituitary tumour. The role of collaborative efforts of the autopsy team and the law enforcing agencies are emphasised.

Sudden Cardiac Arrest in an Asymptomatic Zinc Phosphide-Poisoned Patient: A Case Report.

Zinc phosphide is a gray to black powder mainly used as a rodenticide. In contact with gastric fluid, it releases phosphine which is the main toxic material of this compound. Phosphine interferes with oxidative respiratory cycle of the cells, but is generally expected to manifest its toxicity with prodromal signs and symptoms including abdominal pain, nausea and vomiting, metabolic acidosis, and increased liver function tests. A 64-year-old man was referred to our center with the history of ingestion of three full table spoons of zinc phosphide powder with only a mild GI discomfort. Abdominal X-ray revealed radiopaque material in epigastric and abdominal right upper quadrant. Despite treatment with polyethylene glycol and completely normal vital signs and lab tests, he experienced sudden cardiac arrest 19 h after admission. Autopsy showed clues of focal myopathy and fibrosis with evidences of ischemia and congestion in cardiac tissue, pulmonary edema, shrunken bilateral kidneys, and nutmeg yellow liver. Toxicology panel confirmed the presence of phosphine and zinc phosphide in the gastric fluid. The patient deteriorated suddenly despite being completely symptom-free during the hours preceding cardiovascular arrest. Since the cardiopulmonary injury is the most rampant cause of early death, checking of the cardiac enzymes and cardiac monitoring could be beneficial for early detection and efficient management of these patients.

Zinc Phosphides as Outstanding Sodium-Ion Battery Anodes.

To design a high-performance sodium-ion battery anode, binary zinc phosphides (ZnP2 and Zn3P2) were synthesized by a facile solid-state heat treatment process, and their Na storage characteristics were evaluated. The Na reactivity of ZnP2 was better than that of Zn3P2. Therefore, a C-modified ZnP2-based composite (ZnP2-C) was fabricated to achieve better electrochemical performance. To investigate the electrochemical reaction mechanism of ZnP2-C during sodiation/desodiation, various ex situ analytical techniques were employed. During sodiation, ZnP2 in the composite was transformed into NaZn13 and Na3P phases, exhibiting a one-step conversion reaction. Conversely, Zn and P in NaZn13 and Na3P, respectively, were fully recombined to the original ZnP2 phase during desodiation. Owing to the one-step conversion/recombination of ZnP2 in the composite during cycling, the ZnP2-C showed high electrochemical performance with a highly reversible capacity of 883 mA h g-1 after 130 cycles with no capacity deterioration and a fast C-rate capability of 500 mA h g-1 at 1 C and 350 mA h g-1 at 3 C.