For two years Cristalle Bowen put her chemistry degree to good use at the Chicago Heights offices of Silliker, a food safety laboratory. But in July she quit her chemist’s job there to concentrate on her career as a rapper. “The more serious you get about music, it becomes a 24-hour-a-day thing,” says Bowen, aka Psalm One. “So I was kind of like, ‘I have my degree. I might as well let go and really try to make a living at this rap thing.’”

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The record’s a stopgap until next year’s release of The Death of Frequent Flyer, her first album for Minneapolis’s Rhymesayers label, where her labelmates will include Atmosphere, MF Doom, and RJD2 side project Soul Position. It features production by and guest appearances from Overflo, Thaione Davis, Brother Ali, and DJ Ant. “The tracks on the new album have a lot to do with the fact that I was in the process of quitting my job as a chemist,” Bowen says. “It speaks a lot about doing what you love to do instead of just settling for something easier. It’s very much a testament of where I’ve been and where I’m going.”

Her passion for hip-hop was rivaled only by her interest in chemistry. “For some reason I always knew I wanted to be a scientist–I’ve always been a geek when it comes to that,” she says. “I guess I was intrigued by the whole idea of working in a lab coat.” In 1998 she entered the University of Illinois at Urbana-Champaign, pursuing a chemistry major and creative-writing minor. She also began rapping at showcases sponsored by the black student union, where she developed her skills. “I gave myself homework as a rapper,” she says. “Once I realized I could make words rhyme, then I wanted to become versatile, to be able to write to any beat, to make my voice sound different on different songs. Just like actors don’t want to be typecast, I didn’t want people to be able to pin me down as a certain type of rapper.”

Bowen will celebrate the release of Bio: Chemistry II with a show at the Logan Square Auditorium on December 18, and Rhymesayers tentatively plans to release The Death of Frequent Flyer in the spring. Bowen, though, is already looking ahead to the album after that: she’s begun recording new tracks that she says expand her musical range–“playing with my voice some and adding more melody”–and focus her lyrics on gender politics, which she’s only slightly addressed in previous releases.