For people interested outside the US who can't access this test or get negative results I thought this might help: UK: The Kryptopyrroles test is available from an ordering nutritionist or doctor at: *Biolab UK (uses Vitamin C as a stabilizer and a light proof pot). *The Doctors Laboratory in London,aka TDL is the 'premiere' lab in the UK for testing and the NHS uses it. You can also buy it online yourself (cost more) from Medichecks which uses TDL above. Holland: You can use the ELN lab in Holland. I included this as test is allegedly more sensitive than others, they accept samples from other countries. Germany: You can order it from Lab4More which along with Ganzimmun are the best specialist immunology labs in the world (in my view) for private testing. Email them if you can't speak German using Google Translate. Link above to Lab4more is to Adobe PDF test list otherwise if you can't read German you'd struggle to find the link to it on their main page. In an ideal world, I always use multiple labs to see if there are any gross differences in reporting ranges. Also, having a positive result from a 'trusted' lab like TDL in UK would support a positive result from a non accredited private lab like REDLABS in Belgium for example. Thanks.