Cardiomyopathy from 1,1-Difluoroethane Inhalation

Multi-organ system failure secondary to difluoroethane toxicity in a patient "huffing" air duster: a case report

Inhalant misuse is a growing concern among Americans. According to recent reports by the National Institutes of Health and the Substance Abuse and Mental Health Services Administration, the prevalence of teenage inhalant misuse is increasing. Of the many household items that are "huffed", refrigerant-based propellant cleaners or air dusters, are one of the most misused. Although commonly referred to as "compressed air", refrigerant-based propellant cleaners contain harmful fluorinated hydrocarbons, such as 1,1-difluoroethane, that have significant toxic effects when inhaled. While the central nervous system is primarily affected, there are case reports of cardiovascular, renal, hepatic, and musculoskeletal injury secondary to 1,1-difluoroethane toxicity. However, there are few cases that have presented 1,1-difluoroethane toxicity leading to multi-organ system failure in adults with a long history of inhalant misuse. We present a unique case of multi-system organ failure secondary to 1,1-difluoroethane toxicity in a middle-aged female that was "huffing" a refrigerant-based propellant aerosol duster for more than three months. This case stresses the importance of obtaining a detailed social history to identify inhalant misuse in patients that present with acute illness of unknown etiology. This case also highlights the importance of early communication with toxicology professionals for treatment and supportive care recommendations in patients presenting the life-threatening 1,1-difluoroethane toxicity. Furthermore, this case demonstrates that 1,1-difluoroethane toxicity in the setting of "huffing" air duster has the potential to cause multi-organ system failure.

1,1-Difluoroethane Detection Time in Blood after Inhalation Abuse Estimated by Monte Carlo PBPK Modeling

(1) Background: Inhalant abuse and misuse are still widespread problems. 1,1-Difluoroethane abuse is reported to be potentially fatal and to cause acute and chronic adverse health effects. Lab testing for difluoroethane is seldom done, partly because the maximum detection time (MDT) is unknown. We sought to reliably estimate the MDT of difluoroethane in blood after inhalation abuse; (2) Methods: MDT were estimated for the adult male American population using a physiologically based pharmacokinetic (PBPK) model and abuse patterns detailed by two individuals. Based on sensitivity analyses, variability in huffing pattern and body mass index was introduced in the model by Monte Carlo simulation; (3) Results: With a detection limit of 0.14 mg/L, the median MDT was estimated to be 10.5 h (5th-95th percentile 7.8-12.8 h) after the 2-h abuse scenario and 13.5 h (10.5-15.8 h) after the 6-h scenario. The ranges reflect variability in body mass index and hence amount of body fat; (4) Conclusions: Our simulations suggest that the MDT of difluoroethane in blood after abuse ranges from 7.8 to 15.8 h. Although shorter compared to many other drugs, these MDT are sufficient to allow for testing several hours after suspected intoxication in a patient.

The development of environmentally acceptable fluorocarbons

Chlorofluorocarbons (CFCs) were introduced in the 1930s as the safe replacements for the toxic and flammable refrigerants being used at that time. Subsequently, hydrochlorofluorocarbons (HCFCs) were also developed. In addition to refrigerant applications, they were used as foam blowing agents, as solvents and as propellants for many aerosols. In the 1970s and 1980s, concern developed about their environmental impact, specifically on stratospheric ozone depletion. Industry began to consider acceptable replacements. In 1987, many of the governments of the world came together and drafted the Montreal Protocol, calling upon Industry to initially phase out production of the CFCs and later HCFCs. Within 4 months of the signing of the Montreal Protocol, the 15 global major producers joined together to form the Alternative Fluorocarbons Environmental Acceptability Study (AFEAS), which sponsored research into environmental effects and the Program for Alternative Fluorocarbons toxicity Testing, PAFT), which examined the toxicology of potential replacements for the CFCs and HCFCs. Nine replacements were identified by companies and, through this international cooperation; toxicology programs were designed, conducted, and evaluated without duplication of effort and testing; consequently these new products were introduced within less than 10 years. Indeed the Montreal Protocol has been recognized as the most appropriate international treaty to phase-down HFCs. In 2016 the Kigali Amendment to the Montreal Protocol set out a phase-down schedule for the consumption and production of HFCs. In order to reduce the consumption and emissions of high GWP HFCs. Recently lower GWP HFCs and very low GWP HFOs (hydrofluoroolefins and HCFOs (hydrochlorofluoroolefins) have been introduced into a range of applications. Summaries of the toxicology profiles of some of the original CFCs and HCFCs, the replacements and the new post-PAFT replacements are described. The chemicals in this review include CFC-11, CFC-12, CFC-113, CFC-114, HCFC 22, HCFC-123, HCFC-124, HCFC-141b, HCFC-142b, HCF-32, HFC-125, HFC-134a, HFC-143a, HFC-152a, HFC-245ea, HFC-245fa, HFO-1234yf, HFO-1234ze, and HCFO-1233zd.

Inhalation of 1-1-difluoroethane: A Rare Cause of Pneumopericardium

We report a case of a 32-year-old man with a past medical history of ethanol use disorder who was brought in unresponsive after inhaling six to 10 cans of the computer cleaning product, Dust-Off. After regaining consciousness, he endorsed severe, pleuritic chest and anterior neck pain. Labs were notable for elevated cardiac enzymes, acute kidney injury, and his initial electrocardiogram (ECG) revealed a partial right bundle branch block with a prolonged corrected QT interval (QTc). On chest X-ray as well as chest computed tomography, the patient was found to have pneumomediastinum, pneumopericardium, and subcutaneous emphysema. The patient’s course was uneventful and he was discharged home two days later after extensive substance abuse cessation counseling. Intentionally inhaling toxic substances, also known as “huffing,” is a dangerous new trend with significant consequences that clinicians need to be aware of and suspect in young patients presenting with chest pain. We present a rare case of pneumopericardium induced by inhalation of Dust-Off (1-1-difluoroethane).

Inhaling Difluoroethane Computer Cleaner Resulting in Acute Kidney Injury and Chronic Kidney Disease

Difluoroethane is the active ingredient in various computer cleaners and is increasingly abused by teenagers due to its ease of access, quick onset of euphoric effects, and lack of detectability on current urine drug screens. The substance has detrimental effects on various organ systems; however, its effects on the kidneys remain largely unreported. The following case report adds new information to the developing topic of acute kidney injury in patients abusing difluoroethane inhalants. In addition, it is one of the first to show a possible relationship between prolonged difluoroethane abuse and the development of chronic kidney disease in the absence of other predisposing risk factors.