Wood Tar Research Articles

98/00347 Production of granulated activated carbon from coal and wood tar

98/00347 Production of granulated activated carbon from coal and wood tar

Carcinogenity of medicinal ointments containing crude oil, petroleum products, coal tar, or wood tar

Carcinogenity of medicinal ointments containing crude oil, petroleum products, coal tar, or wood tar

Separation of phenols from Eucalyptus wood tar

Isolation of phenols from Eucalyptus wood pyrolysis tar was carried out with the objective of recovering valuable pure phenols, such as phenol, cresols, guaiacol, 4-methylguaiacol, catechol and syringol. The approach included a primary conversion of the raw wood tar into a lighter oil. Phenolic compounds were further separated from the oil by liquid-liquid extraction using alkali and organic solvents. GC/MS analysis of acetyl-derivatized phenolic compounds was used to evaluate the separation method. The primary conversion allowed the isolation of a lighter oil containing the desirable compounds without causing major chemical changes in the distilled oil. Liquid-liquid extraction by alkali and organic solvents essentially yielded a phenolic fraction. Removal of phenols was more efficient under highly alkaline conditions. An evaluation of the analytical procedure for the determination of phenols was also undertaken.

Recovery of Wood Preservatives from Wood Pyrolysis Tar by Solvent Extraction

Wood pyrolysis tar, which was discharged as a waste by-product in the production of charcoal from larch, was separated into several fractions by solvent extraction using tetrahydrofuran, benzene, and aqueous alkali. The fractions obtained were physicochemically characterized and examined for wood preservative effectiveness. This separation method compared favorably with fractional distillation in the effectiveness and safety of wood preserving components recovered, as well as the operational economy. Such a selective, safe, and inexpensive recovery of wood preservatives will be thus a promising utilization route of waste wood tar.

Acute toxicity of wood tar and dieldrin to Lebistes reticulatus (PL).

Acute toxicity of wood tar and dieldrin to Lebistes reticulatus (PL).

Studies on Active Principles of Tars. X. The Structures and Some Reactions of Antifungal Constituents in Pix Pini.

By following the antifungal activity, four antifungal principles, acetovanillone(1), two new cyclic β-diketones, (2 and 3), and an unknown compound (4), were isolated from wood tar, Pix Pini, which has been used traditionally for the treatment of fungal diseases in Japan. The structures of 2 and 3 were established by synthesis to be 1, 1', 3, 3'-tetraoxo-2, 2'-bicyclopentyl and its 4-methyl derivative, respectively. Chemical reactivities and physical properties of 2 and 3 are also described.

Utilization of quantitative structure-activity relationships (QSARs) in risk assessment: Alkylphenols

Alkylphenols are a class of environmentally pervasive compounds, found both in natural (e.g., crude oils) and in anthropogenic (e.g., wood tar, coal gasification waste) materials. Despite the frequent environmental occurrence of these chemicals, there is a limited toxicity database on alkylphenols. We have therefore developed a “toxicity equivalence approach” for alkylphenols which is based on their ability to inhibit, in a specific manner, the enzyme cyclooxygenase. Enzymeinhibiting ability for individual alkylphenols can be estimated based on the quantitative structure-activity relationship developed by Dewhirst (1980) and is a function of the free hydroxyl group, electron-donating ring substituents, and hydrophobic aromatic ring substituents. We evaluated the toxicological significance of cyclooxygenase inhibition by comparison of the inhibitory capacity of alkylphenols with the inhibitory capacity of acetylsalicylic acid, or aspirin, a compound whose low-level effects are due to cyclooxygenase inhibition. Since nearly complete absorption for alkylphenols and aspirin is predicted, based on estimates of hydrophobicity and fraction of charged molecules at gastrointestinal pHs, risks from alkylphenols can be expressed directly in terms of “milligram aspirin equivalence,” without correction for absorption differences. We recommend this method for assessing risks of mixtures of alkylphenols, especially for those compounds with no chronic toxicity data.

Contact allergy to spices

A group of 103 patients suspected of contact allergy was tested with the European standard series, wood tars and spices: paprika, cinnamon, laurel, celery seed, nutmeg, curry, black pepper, cloves, white pepper, coriander, cacao and garlic. 32 patients (Group I) were selected on the basis of positive tests to one or more of possible indicators for allergy to spices: colophony, balsam of Peru, fragrance-mix and/or wood tars. 71 patients (Group II) showed no response to these indicators. In Group I (n = 32) a statistically significantly higher % of patients (47%) showed positive reactions to 1 or more spices, compared with 15% in Group II (N = 71). Among the spices, the highest numbers of reactions were found to nutmeg (28%), paprika (19%) and cloves (12%) in the indicator-positive Group I. Fragrance-mix turned out to be a particularly important indicator allergen, especially for paprika, nutmeg and cloves. The contact allergy in 11 out of 32 (Group I) and 7 out of 25 patch-tested patients (recruited from Group II) appeared to be directed mainly against the ether-extractable volatile fractions of the spices.

Behavior of phenolic compounds related to wood tar in quantitative HRGC with on‐column injection

Behavior of phenolic compounds related to wood tar in quantitative HRGC with on‐column injection

Wood tars allergy, cross‐sensitization and coal tar

In a population of 1883 patients tested for allergic contact dermatitis (1985-1988), a prevalence of 5.4% (103 cases) was seen for wood tars (ICDRG allergen, 12% pet.) sensitization. In this group (n = 103), retrospectively, a combined allergy was seen to wood tars and fragrance mix in 43% and to wood tars and balsam of Peru in 31%. A combined allergy to wood tars and coal tar was seen in 19 patients (18.5%): 14 to liquor carbonis detergens (LCD), 8 to lianthral and 3 to both LCD and lianthral. Within the group with wood tars allergy (n = 103), a minority (n = 37) had a history of atopic dermatitis. Comparison of the test results in atopic and non-atopic subgroups (within the group of 103) revealed a higher incidence of combined wood tars-fragrance mix allergy in the atopic group (n = 37). In this group, a lower incidence of combined wood tars-coal tar sensitization was seen in comparison with the non-atopic group (n = 66). The authors believe that combined "wood tars-coal tar" allergy could be the consequence of cross-sensitization rather than due to long-term previous topical treatment with tar derivatives. The high % of cross-allergy between wood tars and fragrance mix emphasizes the role of wood tars as an important indicator allergen in perfume allergy.

Betulin aus archäologischem Schwelteer / Identification of Betulin in Archaeological Tar

A compound obtained from an early Iron-Age wood tar via “Kugelrohr”-distillation or extraction was identified as betulin by TLC. 1H - and 13C - NMR as well as by mass spectroscopy. This result validates the assumption that birch was used for the preparation of the archaeological wood tar found at the excavation in Stillfried a .d . March. Lower Austria.

Proof of a pine wood origin for pitch from Tudor (Mary Rose) and Etruscan shipwrecks: application of analytical organic chemistry in archaeology

Six samples of tar and pitch from the wreck of the Mary Rose (Tudor, AD 1509–45) and a sample of pitch from an Etruscan shipwreck (ca. 600 BC) have been analysed by a number of modern analytical techniques (elemental analysis, IR and NMR spectroscopy, GC and GC-MS). Similar analyses were performed on samples of contemporary tars, derived from natural sources, for comparative purposes. The major constituents of the archaeological samples were observed to be alkyl-substituted, tricyclic diterpenoids based on the abietane and pimarane skeletons. Similar molecular compositions and spectral properties were found for Stockholm tar (a good quality wood tar obtained by the destructive distillation of Pinus sylvestris), and Tudor and Etruscan pitches, thus providing conclusive evidence for the derivation of the archaeological samples from pine wood. The analytical techniques utilised are compared for their relative usefulness in chemical archaeology.

STRUCTURAL CHARACTERIZATION AND THERMODYANAMIC PROPERTY ESTIMATION FOR WOOD TARS: A FUNCTIONAL GROUP APPROACH

ABSTRACT A general method for estimating functional group concentrations in complex liquid mixtures is applied to a set of wood tars. The concentrations are estimated using a least squares fit to elemental analysis, H NHR and 13c NMR data. The resulting concentrations, in combination with group additivity rules, are used to estimate thermodynamlc properties for the wood tars.

Patch testing with European and American standard allergens in Japanese patients.

256 patients with a clinical diagnosis of contact dermatitis were patch tested with European standard series allergens in a period from 1976 to 1979. Significant positive reactions were observed with all allergens, among which were paraphenylenediamine (7.8%), wood tars (7.8%), formaldehyde (7.0%), balsam of Peru (6.6%), neomycin (5.1%), ethylenediamine (0.8%), naphthyl-mix (0.8%), mercapto-mix and PPD-mix (1.2%). North American Standard Series allergens were also patch tested in another 178 patients in the years 1976, 1977, 1979, 1980. Similar results were obtained with allergens common to both series and, of the others, ammoniated mercury (12.9%), thimerosal (9.5%), captan (5.6%), and hydroxycitronellal and Caine mix (4.5% each) were positive.

Influence of topically applied corticosteroids on patch test reactions.

Four commercially available corticosteroid preparations were assayed for their capacity to suppress patch test reactions with contact allergens (nickel sulfate, nitrofuralum, potassium dichromate, epoxy resin, wood tars and Maneb) in sensitized individuals (n=14). Beta-methasone valerate, betamethasone dipropionate, hydrocortisone-17-butyrate and triamcinolone acetonide (0.05-0.7% solutions in isopropanol or ethanol) were applied under occlusion in amounts of 0.01, 0.02 and 0.04 ml, respectively. Patch tests were performed on the pretreated skin sites. The patches were removed 24 h after application and the reactions were read 15 min and 24 h later. The intensity of the reactions and the size of the infiltrated areas of the pretreated sites were measured and compared with those of a control patch test. Topical application of corticosteroids was found to have a suppressive effect both on the intensity as well as on the size of the epicutaneous reactions. No marked difference in the suppression effect of the four corticosteroids could be observed.

Standard patch test results in 3,225 consecutive Danish patient from 1973 to 1977.

From 1973 to 1977 a total of 3,225 patients were patch tested at the Department of Dermatology, Odense University Hospital, Denmark; 1,038 patients reacted to one or more allergens. The data on frequency of the most common allergens are presented. The most common allergens observed were nickel, dichromate, balsam of Peru, wood tar, carba mix and wool alcohols.

Photosensitivity and allergy to aromatic lichen acids, Compositae oleoresins and other plant substances

Sixteen patients with verified light sensitivity to both UVB and UVA wavebands showed allergic reactions to various lichen plants (Parmelia spp., Hypogymnia spp., Pseuodovernia spp., Cladonia spp., Platismatia spp., Physcia spp., Umbilicaria spp. and Cetraria spp.). Among the aromatic lichen compounds, atranorin was observed to be the most frequently involved allergen but also several other isolated lichen acids were immunologically active: d-usnic, evernic, stictic, fumarprotocetraric, lobaric, salazinic, diffractaic and physodic/physodalic acid. Several patients showed allergy to other plant substances from other sources such as seven different species from the Compositae family, alantolactone, balsam of Peru, colophony and wood tars. Sensitivity to known photosensitizers was observed in four patients. Aromatic lichen acids are UV-absorbing substances and several are evidently able to photosensitive human skin.

Photosensitivity and allergy to aromatic lichen acids, Compositae oleoresins and other plant substances.

Sixteen patients with verified light sensitivity to both UVB and UVA wavebands showed allergic reactions to various lichen plants (Parmelia spp., Hypogymnia spp., Pseudovernia spp., Cladonia spp., Platismatia spp., Physcia spp., Umbilicaria spp. and Cetraria spp.). Among the aromatic lichen compounds, atranorin was observed to be the most frequently involved allergen, but also several other isolated lichen acids were immunologically active: d-usnic, evernic, stictic, fumarprotocetraric, lobaric, salazinic, diffractaic and physodic/physodalic acid. Several patients showed allergy to other plant substances from other sources such as seven different species from the Compositae family, alantolactone, balsam of Peru, colophony and wood tars. Sensitivity to known photosensitizers was observed in four patients. Aromatic lichen acids are UV-absorbing substances and several are evidently able to photosensitize human skin.

Balsam of Peru as screening agent for essential oils sensitivity.

The standard series and 35 essential oils were tested on 450 patients with dermatitis. It was found that those simultaneously sensitive to essential oils are more frequently negative than positive to balsam of Peru. The remaining 3 balsams, however (colophony, turpentine and wood tars), are also screening agents for essential oils. All four balsams reveal sensitivity to essential oils in most of the subjects tested. In patients negative to all 4 balsams of the standard series, attempts to find an essential oil with which tests would be simultaneously frequently positive with those for other essential oils failed.

Allergy to balsam of Peru and wood tars: an increasing problem?

Allergy to balsam of Peru and wood tars: an increasing problem?