Human absorption of monoterpenes after a 2-h forest exposure: A field experiment in a Mediterranean holm oak forest.

The current body of literature points monoterpenes as one of the determinant factors of the interaction between forests and human health. The present study aims at analyzing the monoterpene absorption by humans during a 2 -hs forest exposure in a Mediterranean holm oak forest focusing on the four most abundant monoterpene compounds: alpha-pinene, beta-pinene, alpha-phellandrene and limonene. Participants' blood samples were collected before and after exposure to forest or urban environment (control). We conducted air and blood sampling using cartridges and head space method and determined the monoterpene compounds through CGMS. We identified the four compounds in forest air during the experimental study being alpha-pinene the monoterpene with the greatest concentration. Results show no significant changes in monoterpene blood concentrations for the forest and control group. However, a negative significant relationship between absorption and baseline blood concentration of the most abundant forest air monoterpenes, alpha-pinene and beta-pinene, was found in individuals visiting the forest, i.e. higher absorption was found the lower the baseline blood concentration was. Although no significant lineal correlation could be spotted between the vital variables and the monoterpene absorption, we found significant correlations between the absorption of the monoterpene compounds. This attempt, first in a Mediterranean holm oak forest, can serve as a starting point and constitute a valuable contribution for further research in regard to experimental design and laboratory analysis.

Protected Natural Areas: In Sickness and in Health.

Numerous studies show the benefits that contact with the natural environment have for human health, but there are few studies on the role of Protected Natural Areas (PNAs), either from the preventive point of view or on their potential benefits, on individuals with health problems. A study was made of the relationship between the visitation of Montseny Natural Park and Biosphere Reserve and health, from the perspective of a population group with different diseases. A total of 250 patients resident in the areas near the park were surveyed, recording their beliefs about the benefits of nature, as well as the reasons for visiting and the activities associated with health that they carried out in the park. The pure air is the most valued benefit (27.2%), particularly for those with allergies. The majority (57%) visit the park for health reasons. High levels (82%) of exercise are recorded, especially by patients with heart diseases (85%), and 65% exercised in the park. More physical activity is mentioned among those that visit the park most often, particularly among those that carried it out for health reasons. Plants were collected for medicinal use by 39.6%. The study confirmed the significant role of the Montseny Natural Park and Biosphere Reserve as a health resource for individuals with diseases that live near it. It also corroborates the beneficial effects that the PNA provide in human health.