Citation

Hendry-Hofer TB, Ng PC, McGrath AM, Soules K, Mukai DS, Chan A, Maddry JK, White CW, Lee J, Mahon SB, Brenner M, Boss GR, Bebarta VS. Inhal. Toxicol. 2020; ePub(ePub): ePub.

Copyright

(Copyright © 2020, Informa - Taylor and Francis Group)

DOI

10.1080/08958378.2020.1866123

PMID

unavailable

Abstract

BACKGROUND: Methyl mercaptan occurs naturally in the environment and is found in a variety of occupational settings, including the oil, paper, plastics, and pesticides industries. It is a toxic gas and deaths from methyl mercaptan exposure have occurred. The Department of Homeland Security considers it a high threat chemical agent that could be used by terrorists. Unfortunately, no specific treatment exists for methyl mercaptan poisoning.

METHODS: We conducted a randomized trial in 12 swine comparing no treatment to intramuscular injection of the vitamin B(12) analog cobinamide (2.0 mL, 12.5 mg/kg) following acute inhalation of methyl mercaptan gas. Physiological and laboratory parameters were similar in the control and cobinamide-treated groups at baseline and at the time of treatment.

RESULTS: All six cobinamide-treated animals survived, whereas only one of six control animals lived (17% survival) (p = 0.0043). The cobinamide-treated animals returned to a normal breathing pattern by 3.8 ± 1.1 min after treatment (mean ± SD), while all but one animal in the control group had intermittent gasping, never regaining a normal breathing pattern. Blood pressure and arterial oxygen saturation returned to baseline values within 15 minutes of cobinamide-treatment. Plasma lactate concentration increased progressively until death (10.93 ± 6.02 mmol [mean ± SD]) in control animals, and decreased toward baseline (3.79 ± 2.93 mmol [mean ± SD]) by the end of the experiment in cobinamide-treated animals.

CONCLUSION: We conclude that intramuscular administration of cobinamide improves survival and clinical outcomes in a large animal model of acute, high dose methyl mercaptan poisoning.

Language: en

Keywords

cobinamide; inhalation; methanethiol; Methyl mercaptan; swine