An alternative is bulk x-ray fluorescence, which would also require around five strands of hair. Scientists subject the hair to high energy x-rays that excite the atoms within, which in turn emit their own x-rays. The frequencies of these secondary x-rays are unique to atoms of different elements, thereby revealing the hair's chemical composition. A variation of the technique, x-ray microprobe fluorescence, requires only a strand or two of hair if researchers have access to an incredibly powerful light source, such as the National Synchrotron Light Source at Brookhaven National Laboratory in Upton, N.Y., or the Diamond Light Source in the U.K.
As a last resort, scientists could try inductively coupled plasma mass spectrometry. Austen's follicles would be dissolved in acid and sprayed into a mass spectrometer—an instrument that atomizes the solution with an intensely hot flame before filtering the atoms for those belonging to a particular element, like arsenic. Jackson estimates that mass spectrometry requires about 10 milligrams of hair—between 10 and 20 strands.
Finding extremely high levels of arsenic in Austen's hair—above three parts per million—would strongly indicate poisoning as the primary cause of the novelist's death. Typical levels of arsenic in human hair do not exceed 0.5 to one ppm.
It is also possible that Austen's earliest symptoms were linked to a different illness and, only when doctors tried to treat it, was she poisoned by arsenic-laced medications. The most popular retrospective diagnosis of Austen's fatal malady is Addison's disease, a rare disorder in which the adrenal glands, walnut-size hormone factories that sit atop the kidneys, begin to malfunction. Symptoms include severe vomiting, fatigue and—as with arsenic poisoning—skin discoloration. These symptoms also match those Austen described in the letters she wrote during the year before her death, which mention "bilious attacks"—her joking name for nausea and vomiting—as well as fever, exhaustion and joint pain.
Noninvasive testing of Austen's hair could provide the clearest answer yet to a long-standing mystery. And it would certainly be less uncouth than unearthing the esteemed novelist's bones—an idea some people have earnestly suggested. Austen, whose novels poke fun at fastidious characters that obsess over appearances and exaggerate illness when convenient, would probably find all the fuss over her hair a little disturbing, but also rather comical.