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The present communication describes the use of an emissions barrier to prevent spread of hydrolysis products from plastizisers in plastic mats and from the glue used to attach such mats onto a concrete slab. In particular, 2-ethylhexanol was focussed at. Elevated air concentrations of 2-ethylhexanol has been associated with a range of health symptoms such as e.g. cough, airways irritation, fatique, skin and mucous membrane irritation. Here we describe how such health problems can be avoided by using an emissions barrier.

The quantification of ergosterol and 3-hydroxy fatty acids (3-OH FAs) in settled house dust by gas chromatography-mass spectrometry was compared with fungal culture while endotoxin by a Limulus amebocyte lysate assay was studied to develop a method for measuring endotoxin and ergosterol in dust. The research used a sample analysis approach that provided an extraction procedure that allowed the measurement of both ergosterol and 3-OH FAs in a single dust sample. Results reveal a wide distribution of 3-OH FA lengths in house dust.

The presence of ester-linked 3-hydroxy fatty acyl-containing lipids in Mycobacterium tuberculosis has been linked to the slow growth pattern and strong chemical-agent resistance of tuberculosis. Therefore, nuclear magnetic resonance spectroscopy and chromatography were used to characterize the three 3-OH-FA-containing lipids and found that they are possibly linked to actinomycetes' fatty acid biosynthesis.

The 3-hydroxy fatty acids of mycobacteria are identified as methyl ester trimethylsilyl ether derivatives by mass spectrometry and gas chromatography. Fourteen to 28 carbon atoms comprising 21 fatty acid chains that are detected reveal that five are 2,4,6-trimethyl branched, 10 are straight and 6 are 2-methyl branched chains. The mycobacterial strains are classified as fatty acid forms.

Gas chromatography-mass spectrometry facilitates the regulation of hydroxy fatty acids and bacterial sugars in dust from air-conditioners. Hydroxy fatty acids, muramic acid and L-glycero-D-mannoheptose are found in large quantity in dust obtained from filters in contact with outdoor air. Considerable amount of gram-negative bacteria is present in the dust from hospital air-conditioning filters.

Secondary alcohols of Mycobacterium xenopi were studied by hexane extraction of whole-cell hydrolysates and analysis by gas chromatography and gas chromatography-mass spectrometry. Nine secondary alcohols were detected, and seven of these were identified as 2-eicosanol, 2-docosanol, 2-octadecanol, 2-nonadecanol, 2-heneicosanol, 2-tricosanol and 2-tetracosanol. The other two compounds were branched-chain secondary alcohols, one with 21 carbon atoms and the other with 23.

Gas chromatography-mass spectrometry (GC-MS) was used to detect 2-docasonol, a chemical marker for Mycobacterium xenopi, and tuberculostearic acid (TSA), a chemical marker for mycobacteria and related species, in drinking water. The results from the GC-MS method agreed well with results obtained by standard culturing techniques. This indicates that GC-MS is a useful technique for the rapid detection of M. xenopi and other mycobacterial species in drinking water.

Abstract Background Exposure to inhaled endotoxins (lipopolysaccharides, LPS) of Gram-negative bacteria commonly found in indoor environments and assessed in secondary tobacco smoke, has been associated with airway inflammation and asthma exacerbation. The bronchoalveolar lavage fluid (BALf) from patients with interstitial lung diseases (sarcoidosis, lung fibrosis, smoking-related ILD, eosinophilic disorders) was analyzed for the markers of lipopolysaccharide (LPS, endotoxin). Methods BALf was obtained from patients with diffuse lung diseases: idiopathic pulmonary fibrosis (n = 42), sarcoidosis (n = 22), smoking-related-ILD (n = 11) and eosinophilic disorders (n = 8). Total cell count and differential cell count were performed. In addition, samples were analyzed for 3-hydroxy fatty acids (3-OHFAs) of 10–18 carbon chain lengths, as markers of LPS, by gas chromatography-tandem mass spectrometry. Results The highest LPS concentration was found in patients with eosinophilic disorders and the lowest in patients with sarcoidosis (p< 0.05) followed by the lung fibrosis and the sr-ILD patients. The difference between LPS in BALf with extremely high eosinophil proportion (> 25%) and those with lower proportion was also significant (p = 0.014). A significant correlation was found between LPS and eosinophils, but not between LPS and lymphocytes, neutrophils, or macrophages count. Conclusions A positive relationship of LPS and eosinophilic pulmonary disorders may be linked to a persistent eosinophil activation mediated by Th2 pathway: chronic endotoxin exposure would intensify Th2 pathway resulting in fibrosis and, at the same time, eosinophil stimulation, and hence in eosinophilic pulmonary disorders.

A case study is provided of a patient infected with human immunodeficiency virus (HIV), the virus associated with AIDS. The patient developed a fatal infection of what was probably mycobacteria, but the specific agent is unknown. Mycobacteria are the group of organisms that cause tuberculosis and leprosy. The patient was an intravenous drug user and was identified as HIV-positive in 1985. When he entered the hospital in 1987 with AIDS symptoms, acid-fast rods (typical of mycobacteria) were located in biopsy specimens taken from intestine and bone, as well as in feces and urine. However, attempts to grow the organism under laboratory conditions were not successful. The patient received drug treatment, but stopped voluntarily and left the hospital. When he returned the following year, acid-fast rods were found in blood samples. He died in 1988. Material from the patient's liver and spleen was prepared for inoculation into mice (athymic mice, which lack a functional immune system). Although it appeared that the organism associated with the acid-fast rods had killed this immunocompromized patient, the organism could not be identified. Some features of the patient's symptoms were suggestive of infection with Mycobacterium avium-intracellulare, but these can be grown in tissue culture. Other specific agents were also ruled out. Immunocompetent mice did not become infected with the agent, but almost all the athymic mice tested developed lesions similar to the patient's. (Consumer Summary produced by Reliance Medical Information, Inc.)