I usually try to begin these blogs with a pop culture reference or a joke that is somehow tangentially related to the topic of the post. However, no matter how hard I attempted to try and make a connection with today’s topic, I had no luck making it work. So, I decided that I would just ramble on and on about my failed endeavor in the space where there’d usually be some sort of introductory story, and that would be my introductory story! Is there a literary device related to what I’m trying to accomplish here? I feel like it should have a name, if it doesn’t have a name already. Maybe I’m the trailblazer for this style of writing and it’ll be named after me!
…Anyway, today’s toxic substance topic is a solvent known as 1,1,1-trichloroethane (TRI).
User: Armtuk. “1,1,1-trichloroethane.” Wikimedia Commons. April 2007.
Source
Also known as methyl chloroform, 1,1,1-trichloroethane was a widely-used organic solvent used as a metal degreaser and spot cleaner among many other uses. 21% of surveyed hazardous waste sites had TRI present in them, according to Pohl et al. The Montreal Protocol designated TRI as a ozone-depleting substance and planned to phase it out by 2002, but it is still used in the United States as a precursor for hydrofluorocarbons as well as being present in some cleaning products. It was also used in correction fluid products such as liquid paper.
Biotransformation
TRI is poorly metabolized in the body and is mostly cleared through exhalation in humans because its biotransformation is limited.
Toxicokinetics/Toxicity
TRI is rapidly and extensively absorbed from the lungs and is distributed throughout the body, mostly accumulating in fat. Uptake decreases with longer duration of exposure as its slow metabolism leads to systemic accumulation. TRI is rapidly cleared after cessation of exposure.
TRI is currently classified as D (not classifiable as to carcinogenicity in humans) by the EPA.
TRI is one of the least toxic chlorinated hydrocarbons; still, toxic inhalation or ingestion levels can lead to CNS depression ranging from dizziness and headache to respiratory arrest, loss of consciousness, and death. The mechanism of action is not well understood. (EPA)
Biomarkers
With its poor metabolism, presence of TRI itself in bodily fluid is a primary biomarker as well as a metabolite, trichloroacetic acid (ATSDR).
References:
Agency for Toxic Substances and Disease Registry. Toxicological profile for 1,1,1-trichloroethane. U.S. Department of Health and Human Services. July 2006. pp. 140-141 https://www.atsdr.cdc.gov/ToxProfiles/tp70.pdf
Environmental Protection Agency. Interim Acute Exposure Guideline Levels For NAS/COT Subcommittee for AEGLs . 1,1,1-trichloroethane. June 2000.https://www.epa.gov/sites/production/files/2014-08/documents/tsd203.pdf
Klaassen, C.D., Ed. (2013). Casarett and Doull’s Toxicology: The Basic Science of Poisons (Links to an external site.). 8th Edition, McGraw-Hill. Chapter 24