To the Editor:
Smoke fluid is used in clubs and theaters to generate artificial smoke with a smoke machine. It may contain various compounds, for example, glycerol or polyglycols. Ingestion of smoke fluid is rare. Only four cases were reported to the Dutch National Poisons Information Center from 2006 to 2011. However, this number increased in 2012, when eight oral exposures to smoke fluid were reported. In most cases, the ingested dose was limited to a few sips and no toxic effects were reported. However, one patient developed an unexpectedly severe intoxication as described in the following case.
A 48-year-old man (72 kg) accidentally used smoke fluid to make coffee. He swallowed three mouthfuls of the fluid on day 1. He developed nausea on day 3. On day 7 he sought medical advise for fever, vomiting, diarrhea, back pain, and oliguria. On day 9 he was hospitalized with acute renal failure. Abnormal lab results included urea 29.8 mmol/L, creatinine 1590 μmol/L, glomerular filtration rate 2.8 mL/min, and potassium 5.4 mmol/L. Osmolal gap, anion gap, and pH were unfortunately not determined. Hemodialysis was started. Ultrasound showed echo dense areas in the right kidney. A kidney biopsy showed interstitial nephritis with eosinophils and focal toxic damage to tubular epithelium. During admission, he developed interstitial lung edema, blurred vision, hearing impairment, left-sided facialis paralysis, convulsions, and arrhythmia. MRI of the brain on day 14 showed symmetrical cortical and subcortical abnormalities, particularly in the posterior flow area and watershed locations. MRI of the brain on day 25 showed clear improvement, with only residual white matter changes. However, blurred vision and hearing impairment were not fully resolved and dialysis was still necessary when he was discharged to a rehabilitation center on day 34.
The name and composition of the smoke fluid were initially unknown. Analysis of the product by the hospital pharmacist by gas chromatography–flame ionization detection and gas chromatography–mass spectrometry showed trace amounts of propylene glycol and a large, unidentified peak. When the name of the product was traced by relatives of the patient, the safety data sheet of the product could be consulted. This safety data sheet only stated that the product contained a “high purity polyglycol”, with an EINECS number referring to diethylene glycol (DEG). After contacting the producer, he confirmed that the product contained 60% DEG.
DEG is an industrial solvent. It has been involved in numerous epidemic poisonings worldwide, resulting from the addition of DEG to pharmaceutical products instead of more expensive, but non-toxic, glycols or glycerin constituents.Citation1,Citation2 Exposure to DEG through the ingestion of smoke fluid is rare. Our patient reportedly ingested three mouthfuls of smoke fluid, corresponding to an estimated maximum amount of 75 mL. With a body weight of 72 kg, the systemic dose of pure DEG (100%) was approximately 0.63 mL/kg (0.70 g/kg). The toxic and lethal doses of DEG are not exactly known. Among others, a mean non-fatal toxic dose of 0.86 mL/kg (0.96 g/kg) and a mean fatal toxic dose of 1 mL/kg (1.13 g/kg) were reported in adults (assuming a body weight of 70 kg).Citation3 The estimated dose of 0.63 mL/kg in our patient is within the same order of magnitude. However, toxic and fatal doses reported in the literature differ considerably and often show considerable overlap with non-toxic and non-fatal doses within the same studies.
The symptoms displayed by our patient are well in agreement with a serious DEG intoxication.Citation2 Since fomepizole was shown to block the toxicity of DEG in rats, patients may benefit from treatment with fomepizole soon after exposure.Citation4 By the time our patient sought medical advise (day 7), treatment with fomepizole was not useful anymore.
Most cases of smoke fluid ingestion do not result in significant toxicity. However, the composition of smoke fluid differs considerably among different brands and is often unknown to the patient and the treating physician. Poison centers and clinical toxicologists need to realize that smoke fluid may contain unusually high concentrations of DEG, making it highly toxic. Since DEG is not included in most standard laboratory analyses, the diagnosis of DEG poisoning may be missed or delayed, increasing the risk of severe intoxications.
Declaration of interest
The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.
References
- Alkahtani S, Sammons H, Choonara I. Epidemics of acute renal failure in children (diethylene glycol toxicity). Arch Dis Child 2010; 95: 1062–1064.
- Schep LJ, Slaughter RJ, Temple WA, Beasley DM. Diethylene glycol poisoning. Clin Toxicol 2009; 47:525–535.
- Calvery HO, Klumpp TG. The toxicity for human beings of diethylene glycol with sulfanilamide. South Med J 1939; 32:1105–1109.
- Besenhofer LM, Adegboyega PA, Bartels M, Filary MJ, Perala AW, McLaren MC, McMartin KE. Inhibition of metabolism of diethylene glycol prevents target organ toxicity in rats. Toxicol Sci 2010; 117:25–35.