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mrsgeologist t1_j8g8gbi wrote

I am a geologist and work in the environmental remediation space. I responded to a similar post earlier today under the NoVA page.

There is a lot of misinformation out there on the internet in regards to this emergency response event. There is no way this event could impact us in the DMV. The half-life of vinyl chloride is 1-2 days in air (meaning it ceases to exist after that time). If you refer to a vinyl chloride Safety Data Sheet, you will determine that it is a liquid under pressure, but immediately becomes explosive when mixed with air. That is why the emergency response entity determined that they had to “burn” it off. There really was no other way to deal with the vinyl chloride once it was exposed to air. The burn off is scary and unfortunate, but within 1-2 days it is no longer present in the atmosphere. The long term investigation will more so be related with groundwater. That is something I cannot speak to because I have not seen the data and delineation of contamination can take a while to determine. There was an immediate die off of aquatic animals since vinyl chloride is highly toxic and it hit surface water bodies. Aquatic life pull oxygen from water to breath. Vinyl chloride is more soluble in water.

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ghostofhogan OP t1_j8g8qp2 wrote

Wow. Finally, someone who actually knows something provided an intelligible response. Thank you so much for taking the time. 🙏🏻

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HockeyMusings t1_j8ifmhw wrote

> There is no way this event could impact us in the DMV.

Exactly what everyone else was telling you.

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[deleted] t1_j8i1peh wrote

[deleted]

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mrsgeologist t1_j8i2tj0 wrote

Your are almost correct.😊 If the actual half-life (50%) was 1.5 days, then 25% would be 2.25 days. So the high volatilization of vinyl chloride and it’s short half life allows for it to dissipate in roughly 2 days. Could be slightly more but we are splitting hairs at that point.

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Administrative-Egg18 t1_j8kjo3q wrote

If it's like radioactivity, then it would be 3 days. 1.5 days to reduce by 50% and then another 1.5 days to reduce by another 50% to 25%.

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idenTITTY t1_j8hyppe wrote

I thought half life referred to the time it took for the radioactivity, or in this case potency(?), of something to reduce by half

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mrsgeologist t1_j8i26d3 wrote

Half life is not just used for radioactivity. Half life of a chemical reaction is the time it takes to reach 50% of its original concentration. That being said, in the environmental and toxicology space, they utilize that term to denote the timeframe where the chemical is of less concern to be in the atmosphere. Vinyl chloride’s volatilization takes 1 to 2 days in air. “If vinyl chloride is released to the atmosphere, it can be expected to exist mainly in the vapor-phase in the ambient atmosphere and to degrade rapidly in air by gas-phase reaction with photochemically produced hydroxyl radicals with an estimated half-life of 1.5 days.” Direct quote from this technical fact sheet: https://semspub.epa.gov/work/05/437069.pdf

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SunshynFF t1_ja9gjcb wrote

Half life plays a role in medications we take too, for example, my mom takes Lisinopril (A.C.E. inhibitor to lower blood pressure) I took one by mistake one time, doc said not only does it get along with the few meds I take, it's half life is only 12.5hrs. Medications are are at their peak efficiency when most of their ingrediencies are working together to give yo the pest Their half life is considered when the ingrediencies are only working half potential. So bottom line if a medication has 6hr half life, it should affect you for appx 6 hrs, and take aapx 12 h for it to be out of your system.;

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CulturalWasabi t1_j8iptpa wrote

Ceases to exist? Where does it go?

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FSOTFitzgerald t1_ja1yul1 wrote

It’s a chemical compound that breaks down into other less harmful elements and compounds. Where does the wood in a bonfire “go”?

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HockeyMusings t1_j8ifhbt wrote

Half-life aside, how much dilution has taken place between the release and when it got here? It’s practically homeopathic at this point, regardless.

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