A cytotoxicity test protocol for single-wall nanotubes (SWNTs), multi-wall nanotubes (with diameters ranging from 10 to 20 nm, MWNT10), and fullerene (C60) was tested. Profound cytotoxicity of SWNTs was observed in alveolar macrophage (AM) after a 6-h exposure in vitro. The cytotoxicity increases by as high as approximately 35% when the dosage of SWNTs was increased by 11.30 microg/cm2. No significant toxicity was observed for C60 up to a dose of 226.00 microg/cm2. The cytotoxicity apparently follows a sequence order on a mass basis: SWNTs > MWNT10 > quartz > C60. SWNTs significantly impaired phagocytosis of AM at the low dose of 0.38 microg/cm2, whereas MWNT10 and C60 induced injury only at the high dose of 3.06 microg/cm2. The macrophages exposed to SWNTs or MWNT10 of 3.06 microg/cm2 showed characteristic features of necrosis and degeneration. A sign of apoptotic cell death likely existed. Carbon nanomaterials with different geometric structures exhibit quite different cytotoxicity and bioactivity in vitro, although they may not be accurately reflected in the comparative toxicity in vivo.

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National allometric equations covering the most common tree species of Canada’s forests were produced based on tree mass data acquired in the early 1980s during the ENergy from the FORest (ENFOR) program. The equations allow us to calculate the mass estimate of four tree components (foliage, branches, stem bark, and stem wood) using either diameter at breast height or a combination of diameter at breast height and height. Missing from that data set, however, were the data from British Columbia. A usable British Columbia data set was finally found and has now been incorporated into the national data set. Here, we present revised allometric equations for six species covered in the previous work and also found in the British Columbia data set as well as for the “hardwoods”, “softwoods”, and “all species” equations. New equations are also provided for eight species specific to the British Columbia data.