An investigational report into the causes of pine mouth events in US consumers.

Between July 2008 and June 2012, the US Food and Drug Administration received 501 consumer reports of prolonged taste disturbances consistent with pine mouth syndrome. Consumers consistently reported a delayed bitter or metallic taste beginning hours to days following consumption of pine nuts that recurred with intake of any food or meal. This dysgeusia lasted in some cases up to a few weeks, but would eventually resolve without serious health consequences. To evaluate these reports, a questionnaire was developed to address various characteristics of the pine nuts consumed, pertinent medical history of complainants and other dysgeusia-related factors. Pine nut samples associated with 15 complaints were collected for analysis. The investigation of reports found no clear evidence of an underlying medical cause or common trigger that could adequately explain the occurrence of dysgeusia in complainants. Rather, the results of our investigation suggest that the occurrence of "pine mouth syndrome" in US consumers is correlated with the consumption of the pine nut species Pinus armandii.