title: Negative effect of photocopier toner on alveolar macrophages determined by in vitro magnetometric evaluation.
abstract: Photocopier toner has been implicated in the etiology of some pulmonary diseases. We examined here the in vitro toxicity of toner particles to alveolar macrophages. Cell magnetometry revealed that relaxation was not delayed in macrophages exposed to toner, which represents a rapid decrease in the remaining magnetism emitted by phagocytosed magnetite. However, relaxation was delayed in macrophages exposed to silica (positive controls). The release of intracellular LDH enzyme activity to the extracellular space was negligible in cells exposed to toner compared with negative and positive controls. Morphological examinations by light and electron microscopy revealed no abnormal findings in the exposed cells. A histochemical study using TUNEL staining and the electrophoretic profile of DNA obtained from cells exposed to toner and to silica were negative for apoptosis. The results of the present and other investigations into animal exposure indicate that photocopier toner is toxicologically inert. However, although the present study examined only effects in vitro, exposure to toner should be minimized because lung overloading in animals has been reported.
authors.affiliation: Department of Preventive Medicine and Public Health, Kitasato University School of Medicine, Kanagawa, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Furukawa
authors.forename: Yoshiharu
authors.initials: Y
authors.lastname: Aizawa
authors.forename: Mitsushi
authors.initials: M
authors.lastname: Okada
authors.forename: Mitsuyasu
authors.initials: M
authors.lastname: Watanabe
authors.forename: Masato
authors.initials: M
authors.lastname: Niitsuya
authors.forename: Makoto
authors.initials: M
authors.lastname: Kotani
mesh_terms: D016902:Air Pollution, Indoor / Q000009:adverse effects; D000818:Animals; D017209:Apoptosis; D002244:Carbon / Q000009:adverse effects; D003308:Copying Processes; D004195:Disease Models, Animal; D004781:Environmental Exposure; D008171:Lung Diseases / Q000139:chemically induced; D016676:Macrophages, Alveolar / Q000187:drug effects* / Q000502:physiology; D008280:Magnetics; D008297:Male; D016273:Occupational Exposure; D009930:Organic Chemicals; D010316:Particle Size; D051381:Rats; D011916:Rats, Inbred F344; D012822:Silicon Dioxide / Q000009:adverse effects
chemical_list: D009930:Organic Chemicals; D002244:Carbon; D012822:Silicon Dioxide