> UV damage to internal tissues seems unlikely given that the tartrazine dye they used absorbs strongly in the UV region of the spectrum
To expand: "the most hazardous UV radiation has wavelengths between 240 nm and 300 nm" [2]. While tartrazine has a lambda max at 425 nm in water [2], it has a second ridiculously-convenient peak around 260 nm [3].
TL; DR It should be mildly UV protective ceteris paribus.
like an x-ray, I'd risk that for a one-off doctors appointment, but I'd probably not risk it on my body at all times. maybe there are safer dyes that have the same effect
To expand: "the most hazardous UV radiation has wavelengths between 240 nm and 300 nm" [2]. While tartrazine has a lambda max at 425 nm in water [2], it has a second ridiculously-convenient peak around 260 nm [3].
TL; DR It should be mildly UV protective ceteris paribus.
[1] https://ehs.umass.edu/sites/default/files/UV%20Fact%20Sheet....
[2] https://pubchem.ncbi.nlm.nih.gov/compound/Tartrazine#section...
[3] https://www.aatbio.com/absorbance-uv-visible-spectrum-graph-...