June 2021

This is a list of the latest papers we are aware of this month relating to the inhalation of gases and solvents. For information specifically on harms relating to butane, please click here.

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Laughing gas improves depression.

"About one-third of individuals suffering from depression are at risk for treatment resistance. Whereas inhaled 50% nitrous oxide has early antidepressant effects on individuals with treatment-resistant major depression (TRMD), adverse effects can occur at this concentration. In this phase 2 clinical trial, Nagele et al. studied the effects of a single 1-hour treatment with 25% nitrous oxide on depression symptoms in those with TRMD, finding that this lower concentration had comparable efficacy to 50% nitrous oxide over several weeks but was associated with significantly fewer adverse effects. These results highlight that lower concentrations of nitrous oxide may be a useful treatment for TRMD."

Nagele P., Palanca B.J., Gott B., Brown F., Barnes L., Nguyen T., Xiong W., Salloum N.C., Espejo G.D., Lessov-Schlaggar C.N., Jain N., Cheng W.W.L., Komen H., Yee B., Bolzenius J.D., Janski A., Gibbons R., Zorumski C.F. and Conway C.R. (2021). A phase 2 trial of inhaled nitrous oxide for treatment-resistant major depression. Science Translational Medicine, 13(596). DOI: 10.1126/scitranslmed.abe1376.

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The last two decades on preclinical and clinical research on inhalant effects

"This paper reviews the scientific evidence generated in the last two decades on the effects and mechanisms of action of most commonly misused inhalants."

Cruz, S.L., Bowen, S.E. (2021). The last two decades on preclinical and clinical research on inhalant effects. Neurotoxicology and Teratology, 87, September–October 2021. DOI: 10.1016/j.ntt.2021.106999

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Electrophysiological characteristics of patients with nitrous oxide abuse

"This study indicated that chronic nitrous oxide abuse causes abnormal nerve conduction in both upper and lower limbs."

Yan Li, Xiuchun Zhang & Chuansheng Zhao (2021). Electrophysiological characteristics of patients with nitrous oxide abuse. Neurological Research. DOI: 10.1080/01616412.2021.1935101

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A health-based recommended occupational exposure limit for nitrous oxide using experimental animal data based on a systematic review and dose-response analysis

"Based on the body of evidence available to us and taking into account uncertainties related to the use of animal data as the basis of our evaluation, we recommend a health-based OEL of 20 mg/m3 for N2O exposure with a reference period of 8 h per shift."

J.M.L. Menon, J.A.K.R. van Luijk, J. Swinkels, E. Lukas, M. Ritskes-Hoitinga, N. Roeleveld, V. Schlünssen, D. Mandrioli, S. Hoffmann, M. Popa, P.T.J. Scheepers. (2021). A health-based recommended occupational exposure limit for nitrous oxide using experimental animal data based on a systematic review and dose-response analysis. Environmental Research, 201: DOI: 10.1016/j.envres.2021.111575.

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Australia: Just “nanging” around – harmful nitrous oxide use. A retrospective case series and review of internet searches, social media posts and the coroner's database

"We report a case series of symptomatic chronic N2O use, many with ongoing neurological sequelae. Furthermore, a sharp increase in internet searches to obtain N2O cannisters was noted. Education of high-risk student groups on the long-term sequalae is important."

Chiew A.L, Raubenheimer J.E., Berling I., Buckley N.A., Becker T., Chan B., Brett J. (2021). Just “nanging” around – harmful nitrous oxide use. A retrospective case series and review of internet searches, social media posts and the coroner's database. Internal Medicine Journal. DOI: 10.1111/imj.15391.