The influence of environmental toxins on the pulmonary system

The lungs are composed of an architectural framework, conducting airways, and alveolar sacs.To prevent collapse of lung tissue, alveolar type II (AT II) cells produce pulmonary surfactant (PS), an amphipathic material composed mostly of saturated phospholipids and cholesterol that lines the airlwater interface.Alterations to lung cells (neoplastic transformation) or the PS system (composition and function) may result in respiratory complications.We studied the biochemical composition of urethane-induced AT II neoplasms, the role of cholesterol in PS function, and the effect of exposure to pulmonary toxins produced by the mold ,S.chartarum.To assess biochemical alterations of neoplastic mouse lung and excised human lung neoplasms, we used a novel technique called Fourier-transform infrared spectroscopy (FTIR), which provides information based on absorption patterns of molecules.Results showed unique biochemistry of mouse neoplasms compared to normal mouse lung.Analyses of human lung lesions revealed also unique but subtle biochemical differences between neoplasms.To study PS function we used capillary surfactometry (CS), which analyzes the ability of a surface-active material to ensure free airflow, thus simulating the small airways.Results demonstrated that excess cholesterol within PS obtained from healthy and tumor-bearing hypercholesterolemic mice had diminished ability to maintain free airflow.Finally, FTIR analyses of PS from mice exposed to S. chartarum spoÍes demonstrated alterations to PS phospholipids.S. chartarum' s epigenetic properties were revealed by through analyses of lung fibroblast DNA fragmentation.Alterations to DNA biochemistry, excess PS cholesterol, and epigenetic properties of S. chartarurn spore toxins may contribute to the development of reversible and/or irreversible respiratory disorders and diseases.significant cause of high moisture levels.A variety of situations such as flooding, sewage back-up, roof leaks, and defective plumbing installations may cause water damage.Some homes and buildings may have chronic water damage and subsequent mold problems.The Canada Mortgage and Housing Corporation studied chronic mold problems on the Roseau River Anishinabe First Nation Reserve in southern Manitoba, Canada [18].In the spring of 199'7, this community of approximately 1,000 people was evacuated due to flooding from the Red River.At least 114 houses suffered flood damage due mainly to basement seepage and sewage back-up and of these houses approximately 34 werc contaminated with S. chartarum.S. chartarurø samples may be collected via bioaerosol, swab, and bulk sampling methods, and cultured on malt extract agar andlor corn meal agar media plates [11a].Air sampling however, may result in false negatives because spores may not be readily aerosolized under very moist conditions tl141.Identification of S. chartarum (and other microorganisms) relies on cultural and microscopic methods, however new DNA-based techniques are currently being developed and tested such as fungus-specific PCR that may detect low levels of spores with greater accuracy in a timely fashion 1122,1261.S. chartarum gained notoriety in the last century beginning in the 1930-40s and in the mid-nineties for being the cause of health problems, termed stachybotryotoxicosis.This term was coined in the 1930s by a team of Russian scientists when they discovered S. chartarum appearcd to cause illnesses or deaths of thousands of horses that consumed S. chartaru¡ø-infested hay [40].The scientists noted S. chartarum's effect on humans after volunteers(?)rubbed the mold on to their skin and subsequently developed skin rash, coughing, pain in the throat, burning in the nose along with bloody exudate, and KC McCrae: Influence on the pulmonary system

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