A high rate of lead fallout around two secondary lead smelters originated mainly from episodal large-particulate emissions from low-level fugitive sources rather than from stack fumes. The lead content of dustfall, and consequently of soil, vegetation, and outdoor dust, decreased exponentially with distance from the two smelters. Between 13 and 30 percent of the children living in the contaminated areas had absorbed excessive amounts of lead (more than 40 micrograms per 100 milliliters of blood and more than 100 micrograms per gram of hair) as compared with less than 1 percent in a control group. A relationship between blood and hair was established which indicated that the absorption was fairly constant for most children examined. It seemned that the ingestion of contaminated dirt and dusts rather than "paint pica" was the major route of lead intake. Metabolic changes were found in most of 21 children selected from those with excessive lead absorption; 10 to 15 percent of this group showed subtle neurological dysfunctions and minor psychomotor abnormalities.

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The propagation of magnetoelastic shear waves in an infinite self-reinforced plate is studied in this paper. The frequency spectrum for SH-modes in the plate is drawn and it is shown that if the dimensionless wave number is real, the branches are hyperbolas while for imaginary wave numbers, they are ellipses. It is also observed that for higher modes, the dimensionless group velocity approaches 9.9754 as the wave number increases. The group velocity is normalized with respect to the phase velocity of shear waves.For a homogeneous and isotropic medium, on the other hand, the dimensionless group velocity approaches unity. So it is approximately 10 times larger in case of magnetoelastic shear waves in an infinite self-reinforced plate.It is also noted that in a reinforced medium, if both the values of the coupling parameter and the angle at which the wave crosses the primary magnetic field are increased, the values of the dimensionless frequency and group velocity are decreased.

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