Terpenes and terpenoids in chemical sensitivity.

Unlabelled: CONTEXT : Terpenes and terpenoids are a diverse class of organic compounds produced by a variety of plants, particularly conifers. Chemically sensitive patients can be targeted by terpenes and terpenoids, resulting in a triggering of symptoms and pathology. Often patients cannot clear their symptoms from exposure to chemicals unless terpenes and terpenoids are avoided and neutralized along with chemical avoidance and treatment.

Objective: This article evaluates the presence, diagnosis, and treatment of terpenes exposure in chemically sensitive patients.

Design: A double-blind, placebo-controlled, 2-part study was designed to establish the chemically sensitive state of the patients in part 1, followed by a second set of challenges to determine each patient's concurrent sensitivity to terpenes and terpenoids in part 2. In all of the challenges, normal saline was used as a control. A case report illustrates the history of 1 patient and describes the authors' treatment methods.

Setting: The study was developed and conducted at the Environmental Health Center of Dallas (EHC-D) because the environment within the center is 5 times less polluted than the surrounding environments, as determined by quantitative air analysis and particulate counts.

Participants: A total of 45 chemically sensitive patients at EHC-D with odor sensitivity to terpenes. The cohort included 18 males and 27 females, aged 24-62 y.Intervention • Patients were deadapted (4 d) and evaluated in a 5-times-less-polluted environment, which was evaluated using air analysis and particulate counts. After deadaptation, the patients were challenged by inhalation in a controlled, less-polluted glass steel booth inside an environmentally controlled room with an ambient air dose of the toxics in the order of parts per billion (PPB) and parts per million (PPM). These toxics included formaldehyde, pesticide, cigarette smoke, ethanol, phenol, chlorine, new sprint, perfume, and placebo. They were also challenged intradermally with extracts of volatile organic compounds (VOCs), including formaldehyde, orris root, ethanol, phenol, cigarette smoke, chlorine, newsprint, perfume, terpenes, terpenoids, and placebo.

Outcome Measures: Inhaled challenges recorded pulse, blood pressure, peak bronchial flow, and other signs and symptoms 30 min before and at 15-min intervals for 2 h postchallenge. Intradermal challenges recorded wheal size and the provocation of signs and symptoms. RESULTS : Different numbers of patients were tested for each terpenes source because of time-related factors or the cumulative effect of testing, which made patients unable to continue. Of 45 chemically sensitive patients in the study, 43 demonstrated sensitivity to terpenes.

Conclusions: This particular patient group was positive for a number of toxic and nontoxic chemicals provoking their symptoms. This study shows there was a connection between VOCs, other chemicals, and terpenes in chemically sensitive patients in a prospective cohort study. It has also shown the potential for terpenes to exacerbate symptoms of chemical sensitivity. Further research on this topic is recommended.