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

EDA-NOCV Analysis of Donor-Base-Stabilized Elusive Monomeric Aluminum Phosphides [(L)P-Al(L'); L, L' = cAACMe, NHCMe, PMe3]

Herein, we report on the stability and bonding analysis of donor-base-stabilized monomeric AlP species (1-6) of the general formula (L)P-Al(L'); [L = cAACMe, L' = cAACMe, NHCMe, PMe3, (N i Pr2)2 (1-4); L = L' = NHCMe, PMe3 (5 and 6); cAAC = cyclic alkyl(amino) carbene; NHC = N-heterocyclic carbene]. Energy decomposition analysis coupled with natural orbitals for chemical valence (EDA-NOCV) analysis indicates the synthetic viability of this class of species, stabilized in their singlet ground state, in the laboratory. The CL-P bond is found to be a partial double bond (WBI ∼ 1.45), while the CL/PL-Al bond is a single bond (WBI ∼ 0.42-0.69). These bonds are mostly covalent or dative σ/π bonds depending upon the ligands attached. The central P-Al bond is an electron-sharing covalent polar single bond (WBI ∼ 0.80; P-Al) for 1-4 and a dative σ bond for 5 and 6 (WBI ∼ 0.89-0.93; P-Al). The calculated intrinsic interaction energies of the central P-Al bonds are found to be in the range from -116 to -216 kcal/mol (1-3 and 5 and 6). This value is the highest for compound 3, possibly due to the push and pull effects from the ligands PMe3 and cAAC, respectively.

Importance of pesticides for lethal poisoning in India during 1999 to 2018: a systematic review

BACKGROUND

Poisoning is a major problem in India. However, there is little systematic information on the key poisons responsible for most deaths by geographical area and over time. We aimed to review the literature to identify the poison classes causing the greatest number of deaths in India over the last 20 years.

METHODS

We performed a systematic literature review in Medline, Embase and Google Scholar (1999-2018), and Indian online medical journals, to find papers that reported deaths from all forms of poisoning in India, with last search 20 April 2020. We included epidemiological studies, observational studies, randomised trials, interventional studies, and case series published from 1999 to 2018 that showed the number of deaths and autopsy studies indicating the specific poisons or poison classes. Studies providing the case fatality for specific poisons or classes, which enabled calculation of the number of deaths, were also included. We excluded deaths due to animal bites and stings, ethanol or methanol poisoning, and gas inhalation as well as papers reporting a single death (case study of single patient). We grouped the papers into 5-year intervals and identified the two most common poison classes in each paper. We used descriptive statistics to summarise the findings over time based on the causative poison and the location of the study.

RESULTS

We identified 186 papers reporting 16,659 poisoning deaths between 1999 and 2018. The number of publications per 5-year interval showed no clear trend over the period (48, 38, 67, and 36 for consecutive periods). Half of the deaths (n = 8338, 50.0%) were reported during the first 5 years of the study (1999-2003), the number of deaths declining thereafter (to n = 1714 in 2014-2018). Deaths due to pesticide poisoning (94.5%) were dominant across the study period compared to other classes of poison [hair dye paraphenylenediamine poisoning (2.6%), medicine overdose (1.4%) or plant poisoning (1.0%)]. Among the pesticides, aluminium phosphide was the most important lethal poison during the first 10 years before declining markedly; organophosphorus insecticides were important throughout the period, becoming dominant in the last decade as aluminium phosphide cases declined. Unfortunately, few papers identified the specific organophosphorus insecticide responsible for deaths.

CONCLUSION

Use of the published literature to better understand the epidemiology of lethal poisoning in India has clear limitations, including secular variation in publishing practices and interest in poisoning. Unfortunately, there are no long-term detailed, combination hospital and community studies from India to provide this information. In their absence, our review indicates that pesticides are the most important poison in India, with organophosphorus insecticides replacing aluminium phosphide as the key lethal poison after government regulatory changes in 2001 reduced the latter's lethality. Plant and hair dye poisoning and medicines overdose caused few deaths. Aluminium phosphide deaths mostly occurred in northern Indian states, whereas deaths from organophosphorus insecticide poisoning occurred throughout India. Paraquat poisoning has become a clinical problem in the last 10 years. Lethal pesticide poisoning remains alarmingly common, emphasising the need for additional regulatory interventions to curtail the burden of pesticide poisoning deaths in India. More detailed reporting about the specific pesticide involved in lethal poisoning will be helpful to guide regulatory decisions.

Pathological changes induced by phosphine poisoning: a study on 8 children

Aluminum phosphide (ALP) has been extensively used as an economical and effective insecticide, rodenticide, and fumigant. The active ingredient of ALP is phosphine (PH₃), the use of which can lead to accidental inhalation and mass poisoning with high mortality. Exposure to PH₃ will give rise to global damage in the human body. This study reviewed 4 fatal accidents including 8 children with PH₃ poisoning and aimed to determine the pathological changes that resulted from exposure to PH₃ and, secondly, aimed to determine whether oxidative stress was involved in PH₃-induced neurotoxicity using histopathological and immunohistochemistry (IHC) methods. After focusing on the pathological changes on the major organs, we found severe damage induced by PH₃ in many systems, especially the neurological system, including neuronal, axonal, and vascular injuries as well as oxidative damage with increased expression of 4-hydroxy-2-trans-nonenal (4HNE), 8-hydroxy-2'-deoxyguanosine (8-OH-dG), and 3-nitrotyrosine (3-NT) in the brain, which indicated that oxidative stress was a crucial mechanism for neuronal death in PH₃ toxicity. Moreover, we observed severe myocardial and hepatocellular fatty degeneration in the tissues of the heart and liver. We considered that these characteristic changes are a suggestive sign of PH₃ poisoning and partly explained the toxic mechanism of PH₃ (inhibition of mitochondrial oxidative phosphorylation). We hope that this research could improve the understanding of the toxicity of PH₃ in both forensic and clinical practice.

Evaluation of selected ultra-trace minerals in commercially available dry dog foods

PURPOSE

To evaluate the concentrations of chromium, nickel, molybdenum, silica, and aluminum in several commercially available dry dog foods and compare these with current World Health Organization's (WHO) mean human daily dietary intake. Conversion of dietary intake per megacalorie (Mcal) for both dog foods and human average intake was performed based on the National Research Council recommendation of a 2,900 kcal diet for comparative purposes to average intake and potential toxic exposure.

MATERIALS AND METHODS

Forty-nine over-the-counter dry foods formulated for maintenance of healthy dogs yet listed as all life stage foods were analyzed. Concentrations of the ultra-trace minerals were measured via inductively coupled plasma atomic emission and represented per Mcal for comparative purposes as it relates to common intake in dogs in comparison with humans.

RESULTS

Chromium, molybdenum, and aluminum concentrations in all of the dog foods were at levels that would be considered above average human daily consumption on a caloric basis. Nickel and silica calculated intakes per Mcal were comparable with human intake patterns, while both trace minerals displayed outliers exceeding at least twofold of the upper range of human daily intake.

CONCLUSION

Overall, ultra-trace minerals found in dog foods were above the expected average daily intake for humans on a caloric basis. There was no evidence of potential chronic toxic exposure based on presumptive intake extrapolated from WHO published toxic intake concentrations for humans or domestic animals. The large range of silica intake from various foods (2.96-83.67 mg/1,000 kcal) may have health implications in dogs prone to silica urolithiasis. Further studies investigating the bioavailability of these ultra-trace minerals and establishing dietary ultra-trace mineral allowance would be ideal; however, based on these findings, consumption of these ultra-trace minerals in over-the-counter dry dog foods appears safe.

Moringa oleifera extract (Lam) attenuates Aluminium phosphide-induced acute cardiac toxicity in rats

•

Aluminium phosphide (AlP) affects many organs especially heart.

•

Antioxidant activities of Moringa was investigated after acute AlP intoxication.

•

Moringa preventive effects were determined histopathologically.

•

Moringa significantly re-equilibrates antioxidant parameters back near to their normal values.

Background

Moringa oleifera extract (Lam) has many antioxidant and protective properties. Objective: to investigate the antioxidant activities of Lam in counteracting the high oxidative stress caused by acute sub-lethal aluminium phosphide (AlP) intoxication in rat heart. These activities will be detected by histopathological examination and some oxidative stress biomarkers.

Methods

a single sub-lethal dose of Alp (2 mg/kg body weight) was administered orally, and Lam was given orally at a dose (100 mg/kg body weight) one hour after receiving AlP to rats.

Results

aluminium phosphide caused significant cardiac histopathological changes with a significant increase in malondialdehyde (MDA); lipid peroxidation marker; and a significant depletion of antioxidant enzymes (catalase and glutathione reductase). However, treatment with Lam protected efficiently the cardiac tissue of intoxicated rats by increasing antioxidants levels with slight decreasing in MDA production compared to untreated group.

Conclusions

This study suggested that Moringa oleifera extract could possibly restore the altered cardiac histopathology and some antioxidant power in AlP intoxicated rats, and it could even be used as adjuvant therapy against AlP-induced cardiotoxicity.

Successful management of aluminium phosphide poisoning using intravenous lipid emulsion: Report of two cases

Aluminum phosphide (ALP) is a cheap, easily available agricultural pesticide which causes lethal poisoning by liberation of phosphine and inhibition of cytochrome c oxidase thereby leading to cellular hypoxia. Although there is no known specific antidote, clinical trials are still going on. We present here two cases of ALP poisoning who were successfully managed by treatment with lipid emulsion and intravenous magnesium sulfate.