Content and composition of needle essential oils of Pinus sylvestris (Scots pine) grown in the north of Lithuania have been studied. Volatile components of dried current-year and 1 year old needles were extracted by simultaneous hydrodistillation-extraction and analyzed by GC and GC/MS. The most predominant fraction was found to be monoterpene hydrocarbons (26.4–41.3%), with the major constituents α-pinene (7.0–16.1 %) and δ-3-carene (5.2–14.3 %) in it. Among the oxygenated monoterpenes bornyl acetate was the most dominant constituent (1.1–3.9 %). Sesquiterpene hydrocarbons formed 19.4–26.0 % of the oils; amounts of main sesquiterpenes β-caryophyllene and δ-cadinene were 2.6–5.8 % and 2.3–5.9 %, respectively. α-Cadinol (4.2–8.5 %) and epi-α-cadinol with epi-α-muurolol and α-muurolol (4.0–9.1 %) were the major compounds in oxygenated sesquiterpenes fraction. Diterpenoids (including and tentitatively identified compound) comprised 6.2–13.7 % of the oils. Also, differences in composition of current-year and 1 year old needles were represented in the study. Seventy-one identified component made up 89.1–98.2 % of total oil content. One sample of fresh needles was analyzed in order to compare the composition with oils obtained from dried needles. Relative amount of monoterpene hydrocarbons was significantly higher (71.0 %) in the oil of fresh needles.

The chemical composition of the essential oils of aerial parts of Artemisia campestris ssp. campestris, collected from ten different locations in Lithuania is detailed in this paper. The major component in all the oils was caryophyllene oxide (8.5-38.8%), whereas compounds with the caryophyllane skeleton ranged from 10.2 to 44.5%. Other representative constituents were germacrene D (≤15.0%), humulene epoxide II (≤8.1%), β-ylangene (≤7.7%), spathulenol (≤6.8%), β-elemene (≤6.8%), β-caryophyllene (≤6.2%), junenol (≤6.1%) and α- or β-pinene (≤5.5%). Eighty-seven compounds were identified, comprising 73.6-92.3% of the oils. The chemical composition was highly variable depending on the sample location. Toxicity of A. campestris oils was determined using the brine shrimp (Artemia sp.) assay. LC₅₀ values ranging to 20 μg/mL were obtained for three of the oils after 24 hours of exposure. Data of this test revealed that A. campestris ssp. campestris essential oils with dominant caryophyllene oxide are notably toxic.

Unfavorable anthropogenic factors, such as air pollution, lead to biochemical responses in trees. Changes in the amounts of secondary metabolites may be early indicators of invisible injuries. The aim of this study was to evaluate composition of the essential oils in the needles of Scots pine (Pinus sylvestrisL.) growing in the areas affected by pollutant emissions of main factories in Lithuania: a nitrogen fertilizer factory (NFF), a cement factory (CF), and an oil refinery (OR). Totally, 14 pine stands were examined along transects from the factories (July 2005). Volatile components of the needles were extracted and analyzed by GC and GC/MS. Over 70 components of the essential oils were identified in current-year and 1-year-old needles.Along the CF transect for current-year needles, the percentage of diterpenes was decreasing with the increasing pH of the pine bark (r = -0.582;p< 0.05) or with the increasing concentration of SO₂(r = -0.573;p< 0.05); for 1-year-old needles, the percentage of diterpenes was decreasing with the increasing pH of the bark (r = -0.534; p < 0.05). Along the OR transect, in both the current-year and 1-year-old needles, the percentage of diterpenes was decreasing with the increasing SO₂(respectively, r = -0.773;p< 0.01; r = -0.486;p< 0.05); an opposite relation was true for sesquiterpenes (respectively, r = -0.751;p< 0.01; r = 0.785;p< 0.01). The view was different along the NFF transect. For current-year needles, the percentage of monoterpenes was decreasing with the increasing NH³(r = -0.669;p< 0.01); while the percentage of sesquiterpenes or oxysesquiterpenes was increasing with the increasing NH³(respectively, r = 0.540;p< 0.05 and r = 0.688;p< 0.01). For each transect, cluster analysis of the percentages of components of essential oils in the needles allowed us to distinguish the most contrasting stands according to the concentration of air pollutants. Current-year needles were more effective as indicators of the effects of pollution than 1-year-old needles in the case of the NFF and the OR transects, and both-aged needles were equally valuable in the case of the CF transect. The changes detected in the proportions of components of the essential oils in the needles of the trees affected by the industrial emissions may play a significant role in modifying the susceptibility of the pine stands to the biotic factors, and also may alter emissions of terpenes from the stands to the atmosphere.