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Formaldehyde was removed from embalmed animal cadavers by pumping ethanol (20%) through the pleural and peritoneal cavities of 4 goats, 4 cows and 4 horses. The goats were percolated intermittently for 7 days and the large animals continuously for 72 h. Just after opening the body cavities, samples
A study of 759 histologically verified cancers of the nasal cavity (287 cases), paranasal sinuses (179 cases), and nasopharynx (293 cases) and 2465 cancer controls diagnosed in Denmark between 1970 and 1982 was conducted to investigate the importance of occupational exposure to formaldehyde.
A population-based case-control study was undertaken in 13 counties of western Washington to determine if occupational formaldehyde exposure was related to cancer of the oro- and hypopharynx (OHPC, N = 205), nasopharynx (NPC, N = 27) or sinus and nasal cavity (SNC, N = 53). Controls were selected by
Formaldehyde (HCHO) is the most abundant atmospheric carbonyl compound and plays an important role in the troposphere. However, HCHO detection via traditional incoherent broadband cavity enhanced absorption spectroscopy (IBBCEAS) is limited by short optical path lengths and weak light intensity.
Inhalation exposure for 2 years to 14.3 ppm formaldehyde (HCHO) induced a 50% incidence of squamous cell carcinoma in the nasal cavity of F-344 rats but only a 3.3% incidence in B6C3F1 mice. Since the response was concentration and species dependent, species differences in nasal cavity "dose" were
Histopathological and biochemical examinations of the nasal cavity and lungs of rats inhaling 145.6 ppm (high-dose) or 15.0 ppm (low-dose) formaldehyde vapor for 6 h revealed dose-related damage. The contents of non-protein SH groups (NPSH) in the nasal mucosa and lung, and lipid peroxide (LPO) in
Groups of 120 male and 120 female rats were exposed by inhalation to 0, 2, 6, or 15 ppm formaldehyde vapor 6 hr/day, 5 days/week, for 18 months of a 24-month study. The present communication describes interim findings based on data available after 18 months of exposure. Squamous cell carcinomas
To investigate the possible association between residential formaldehyde exposures and risk of cancer of the oro- and hypopharynx (OHPC, N = 205), nasopharynx (NPC, N = 27) and sinus and nasal cavity (SNC, N = 53), a population-based case-control investigation was carried out in 13 counties of
This case-control study of nasal and paranasal sinus tumors, in males diagnosed between 1978 and 1981 in the Netherlands, was designed to identify environmental risk factors. Special attention was given to assessing any association between nasal cancer and an occupational history of possible
Formaldehyde is a well known nasal carcinogen in rodents, but so far there has been no convincing evidence that workers occupationally exposed to formaldehyde have an increased risk of nasal cancer. In this study three cases of malignant melanoma of the nasal mucosa in persons occupationally exposed
In industrial workers, formaldehyde exposure has been associated with cancer of the nasal cavities, nasopharynx, prostate, lung, and pancreas; however, these associations are inconsistent and remain controversial. Animals exposed to formaldehyde show excesses of nasal cancer. In an extended
A mid-infrared cavity-enhanced sensor system was demonstrated for the detection of formaldehyde (H2CO) using a continuous-wave (cw) interband cascade laser (ICL) centered at 3599 nm. A compact Fabry-Perot (F-P) cavity with a physical size of 38 × 52 × 76 mm3 was developed consisting of two concave
N, N-dimethyl-p-toluidine (DMPT; Cas No. 99-97-8), an accelerant for methyl methacrylate monomers in medical devices, is a nasal cavity carcinogen according to a 2-yr cancer study of male and female F344/N rats, with the nasal tumors arising from the transitional cell epithelium. In this study, we
A gross anatomy laboratory for medical students was evaluated for formaldehyde levels throughout its eight-week term. Results indicated that exposures for students and instructors were below the 3-ppm permissible exposure limit (assuming a maximum of five hours of daily exposure) established by the
Data have recently been obtained on the concentration of formaldehyde covalently bound to the respiratory mucosal DNA of Fischer-344 rats following two 6-hr inhalation exposures to gaseous formaldehyde. These data provide a direct short-term measure of the delivered formaldehyde dose in target