Do you not feel obligated to tell people that such lights are present, in case they have a different assessment of the long-term safety than you do? I remember how ApeFest caused eye damage with UV lights.
Do you not feel obligated to tell people that such lights are present, in case they have a different assessment of the long-term safety than you do?
I do think that’s a good idea, yes:
Before deploying them at the local contra dance we announced a trial. Afterwards we polled attendees (only one person in 200 didn’t like the idea), and announced deployment. Now it’s listed on the website, along with information on our mask requirements and glycol vapor usage.
Before setting one up at Thanksgiving I also wrote to my relatives, linked them to faruvc.org, explained why I thought this was a good idea given my aunt’s immunocompromised status, and asked if anyone had objections.
I had one set up at the EA dinner we hosted last night, but it wasn’t in the main room and I told people about it. I’m planning to announce before the next one that we’ll have it in the main room.
I remember how ApeFest caused eye damage with UV lights.
It sounds like it was UV-A (“blacklight”): “Yuga carried out the investigation with Jack Morton Worldwide, the event agency that produced this year’s ApeFest. Together, they ‘determined that UV-A emitting lights installed in one corner of the event was likely the cause of the reported issues related to attendees’ eyes and skin.’” This would have been visible as a deep purple glow that makes things fluoresce, so the problem is probably not that attendees didn’t know UV-A was present but instead that attendees should be able to trust organizers to keep things like this to a safe level and the organizers didn’t do that.
PG vapor pressure is such that you could potentially just leave open bowls of it instead of needing a vaporizer device.
PG is probably equally effective at disinfection.
PG should have somewhat lower toxicity.
PG is used sometimes in foods as a humectant so it’s relatively available.
About toxicity, tri-glycol is safer than EG because EG is partly metabolized to glyoxal which can permanently form cyclic compounds inside cells. PG is preferentially metabolized to lactic acid before the secondary OH is oxidized, which is why it’s safer, tho yes you could get a small amount of methylglyoxal, so there is that issue, tho methylglyoxal is at least less reactive than glyoxal. The concern I have is that eg, ethoxyethanol is metabolized to ethoxyacetate which is somewhat toxic, and oxidized tri-glycol might be analogous. Note also that ethers eventually get oxidatively cleaved. I’m simplifying a bit here obviously.
Yes, there have been studies, but toxicity studies use high doses in mice to get obvious effects, and then we assume that much lower doses in humans don’t have subtle long-term effects, but the effect of tri-glycol would be limited by the rate of metabolism, and the tri-glycol itself should be safe.
Do you not feel obligated to tell people that such lights are present, in case they have a different assessment of the long-term safety than you do? I remember how ApeFest caused eye damage with UV lights.
I do think that’s a good idea, yes:
Before deploying them at the local contra dance we announced a trial. Afterwards we polled attendees (only one person in 200 didn’t like the idea), and announced deployment. Now it’s listed on the website, along with information on our mask requirements and glycol vapor usage.
Before setting one up at Thanksgiving I also wrote to my relatives, linked them to faruvc.org, explained why I thought this was a good idea given my aunt’s immunocompromised status, and asked if anyone had objections.
I had one set up at the EA dinner we hosted last night, but it wasn’t in the main room and I told people about it. I’m planning to announce before the next one that we’ll have it in the main room.
It sounds like it was UV-A (“blacklight”): “Yuga carried out the investigation with Jack Morton Worldwide, the event agency that produced this year’s ApeFest. Together, they ‘determined that UV-A emitting lights installed in one corner of the event was likely the cause of the reported issues related to attendees’ eyes and skin.’” This would have been visible as a deep purple glow that makes things fluoresce, so the problem is probably not that attendees didn’t know UV-A was present but instead that attendees should be able to trust organizers to keep things like this to a safe level and the organizers didn’t do that.
Interesting.
About glycol vapor, I might personally go with propylene glycol rather than triethylene glycol.
Why?
EG = ethylene glycol, PG = propylene glycol
PG vapor pressure is such that you could potentially just leave open bowls of it instead of needing a vaporizer device.
PG is probably equally effective at disinfection.
PG should have somewhat lower toxicity.
PG is used sometimes in foods as a humectant so it’s relatively available.
About toxicity, tri-glycol is safer than EG because EG is partly metabolized to glyoxal which can permanently form cyclic compounds inside cells. PG is preferentially metabolized to lactic acid before the secondary OH is oxidized, which is why it’s safer, tho yes you could get a small amount of methylglyoxal, so there is that issue, tho methylglyoxal is at least less reactive than glyoxal. The concern I have is that eg, ethoxyethanol is metabolized to ethoxyacetate which is somewhat toxic, and oxidized tri-glycol might be analogous. Note also that ethers eventually get oxidatively cleaved. I’m simplifying a bit here obviously.
Yes, there have been studies, but toxicity studies use high doses in mice to get obvious effects, and then we assume that much lower doses in humans don’t have subtle long-term effects, but the effect of tri-glycol would be limited by the rate of metabolism, and the tri-glycol itself should be safe.