[Two cases of acute freon poisoning]

Freon is widely used in daily life, which is usually absorbed through the respiratory tract and causes clinical manifestations mainly in the cardiovascular system and neurological damage. Now, we analyze the clinical data, diagnosis, treatment and prognosis of two cases of freon poisoning in Affiliated Dongyang People's Hospital of Wenzhou Medical University to improve the clinicians' understanding of freon poisoning and to avoid missed diagnosis and misdiagnosis.

Inhalant misuse reported to America's Poison Centers, 2001-2021

CONTEXT/OBJECTIVE

This study investigated characteristics and trends of inhalant misuse reported to United States poison centers from 2001 through 2021.

METHODS

Using data from the National Poison Data System and the United States Census Bureau, analyses were conducted of demographic and other characteristics, inhalant category, level of health care received, and medical outcome, and population-based rate trends were assessed.

RESULTS

United States poison centers managed 26,446 inhalant misuse cases from 2001 through 2021, which equaled an annual average of 1,259 cases. Most inhalant misuse involved males (73.0%) or a single substance (91.0%). Teenagers accounted for 39.7% of cases. Among inhalant misuse cases, 41.4% were associated with a serious medical outcome and 27.7% were admitted to a healthcare facility. Overall, the rate of inhalant misuse per 1,000,000 United States population increased by 9.6% (P = 0.0031) from 5.33 in 2001 to 5.84 in 2010, followed by a decrease to 2.60 (-55.5%, P < 0.001) in 2021. "Freon and other propellants" showed the largest change in rate, increasing from 1.28 in 2001 to 3.55 in 2010 (P < 0.001), before decreasing to 1.36 in 2021 (P < 0.001). This trend was driven by the 13-19-year-old age group, and the trend reversal in 2010 among teenagers coinciding with an almost complete ban on Freon^TM by the United States Environmental Protection Agency, which it implemented under the Clean Air Act.

CONCLUSIONS

Although the annual rate of inhalant misuse reported to United States poison centers has been decreasing since 2010, it remains an important public health problem. The United States Environmental Protection Agency's 2010 regulation of Freon^TM may have been an important contributor to the dramatic trend reversal and decrease in inhalant misuse rates starting in that year. This may exemplify the potential effect that regulatory efforts can have on public health.

A case report of recreational use of inhaled Freon leading to acute hypoxemic respiratory failure salvaged by veno-venous extracorporeal membrane oxygenation

BACKGROUND

Freon™ is a halogenated hydrocarbon often used as a refrigerant. When inhaled recreationally, it has the desired effects of euphoria and intoxication. Toxic effects include cardiovascular and neurologic insults such as arrhythmias and seizures, and less well-described toxicities include airway and lung injury. The treatment in general is primarily supportive.

CLINICAL FEATURES

We present the case of a 42-yr-old previously healthy male who developed acute bronchiolitis and pneumonitis following inhalation of Freon leading to severe respiratory failure. He was supported by veno-venous extracorporeal membrane oxygenation and managed with high-dose corticosteroids.

CONCLUSION

To our knowledge, this is the first case report of an inhaled Freon exposure resulting in acute lung injury refractory to conventional therapy that was salvaged by vv-ECMO as a bridge towards a full recovery.

Rotational study on the van der Waals complex 1-chloro-1,1-difluoroethane-argon

The rotational spectrum of the van der Waals complex formed between 1-chloro-1,1-difluoroethane and argon has been investigated by using a pulsed jet Fourier transform microwave spectrometer. Only one set of rotational transitions belonging to the lowest energy conformer has been observed and assigned, although theoretical calculations suggest six stable conformers that might be observed. The observed conformer, according to the experimental evidence from two isotopologues (³⁵Cl and ³⁷Cl), adopts a configuration in which the argon atom is located, close to the CF₂Cl top, between the CCF and CCCl planes (the dihedral angle ∠ArCCCl is 65.2°). The distance between argon atom and the center of mass of CH₃CF₂Cl is 3.949(2) Å. The dissociation energy, with pseudo diatomic approximation, is evaluated to be 2.4kJmol^-1.