Rockley Photonics has done a lot of work to make that happen, maybe enough that the answer is “Yes”: <a href="https://rockleyphotonics.com/wp-content/uploads/2021/03/Rockley-Photonics-Health-Investor-Presentation-2021-03.pdf" rel="nofollow">https://rockleyphotonics.com/wp-content/uploads/2021/03/Rock...</a><p><a href="https://rockleyphotonics.com/wp-content/uploads/2021/07/Rockley-Photonics-Biomarker-Sensing-on-the-Wrist.pdf" rel="nofollow">https://rockleyphotonics.com/wp-content/uploads/2021/07/Rock...</a><p>Or summaries: <a href="https://www.macrumors.com/2021/07/14/apple-supplier-unveils-health-tracking-tech/" rel="nofollow">https://www.macrumors.com/2021/07/14/apple-supplier-unveils-...</a> , <a href="https://www.macrumors.com/2021/05/03/apple-watch-blood-pressure-glucose-alcohol/" rel="nofollow">https://www.macrumors.com/2021/05/03/apple-watch-blood-press...</a><p>Whether it’s in the Apple Watch 8, 9, or a special-purpose device is anyone’s guess, as is the accuracy. It seems like they’re pretty far along, though.