State health officials point to isovanillin after Orange County water odor; investigation continues

Dwayne Roadcap, director of the Virginia Department of Health’s Office of Drinking Water, told the Orange County Board of Supervisors the department believes an isomer of vanillin — isovanillin — is the most likely cause of an objectionable odor that prompted a safety advisory in late August.

Roadcap, speaking by video conference, said the compound was detected at concentrations of about 8 to 10 parts per billion in taste‑and‑odor testing. He told the board that VDH’s toxicology review found limited data on isovanillin but noted that vanillin — a related compound the Food and Drug Administration lists as generally recognized as safe for food use — provides some context for the agency’s preliminary risk assessment. Roadcap said the chemicals detected (isovanillin, benzaldehyde and a single detection of BCE) at the concentrations observed would not cause short‑term health concerns.

"The reported concentration…