5780447302

B. Rihn et aUTo.ricology 109 (1996) 147-/56

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0.10-0.25

^rig. 2. Fiber size distribution of the crocidolitc fiber prcparation. Diameter and length are expressed in /im, freąuency in perccnt n the background a typical view of crocidolite fibers by transmission electron microscopy is shown. The crocidolite sample jlementary analysis was carried out by atomie absorption spectroscopy: Mg (1.49), Si (22.83), Fe (30.03), Mn (0.097), Al (0.05), Zr (<0.003), Ni (<0.017), values are in % per element.

Ashing of the lung lobes demonstrated that :ven 1 month after the intoxication, the fiber >urden varied from 361 to 1583 ng/mg corre-;ponding to 345000 to 1 300000 fibers per mg of iried lung. This corresponded to a nominał total oad of 15600000 fibers in the left lobe of the crocidolite intoxicated mouse #3 (Table 1). The calcination method used here does not introduce

Table 1

Fiber burden in crocidolite-intoxicated and control mice

			Weight	Fiber
				Number	Mass	L/D
Treated	Animal	#!	11.0	344.6	360.7	26
	Animal	#2	10.3	580.2	432.2	19
	Animal	#3	12.0	1296.6	1583.0	20
	Mean		11.1	740.5	792.0	22
	Stds		0.9	495.8	686.0	4
Control	Animal	#4	16.7	0.0	0.0	ND
	Animal	#5	9.5	0.0	0.0	ND
	Animal	#6	8.4	0.0	1.0	ND
	Mean		11.5	0.0	0.3	ND
	Stds		4.5	0.0	0.6	ND

The weight of the lung is expressed in mg. The number corresponded to the number x 10 "³ of observed fibers/mg of dried lung and the mass was given in ng/mg of dried lung. Differences in all parameters except the lung weight were statistically significant at P < 0.01. L/D was the ratio of fiber length/diameter.

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