A representative sample of 5-year-old kindergarten children was assessed for speech and/or language disorder. Of the 1,655 children tested, 180 were identified as having speech or language impairment. It is estimated that within the total reference population, between 16.2% and 21.8% would show some impairment; for the boys, the rate would be 15.5% to 20.7% and for the girls, between 19.1% and 25.1%. Most of these children would show some language impairment as opposed to speech problems only. Approximately 36% of the identified boys and 30% of the girls would have speech problems only, the remainder having speech and language problems or language problems only. Followup studies of these children are needed to ascertain their outcome and language status in middle childhood.

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The uptakes of gas-phase SO 2 and H 2 O 2 by ice surfaces have been investigated at temperatures from 213 to 238 K and from 10 -7 to 10 -4 Torr partial pressure. These experiments have been conducted in a lowtemperature, coated-wall flow tube coupled to an electron-impact, quadrupole mass spectrometer which monitors changes in the SO 2 and H 2 O 2 partial pressure. The ice surfaces are formed by freezing liquid water. Unlike the uptakes of strong acids such as HNO 3 and HCl, the SO 2 and H 2 O 2 uptakes are fully reversible on the time scale of the experiment and the surface coverages are roughly a thousandth of a monolayer at 10 -6 Torr partial pressure and 228 K. The SO 2 uptakes scale with the square root of the partial pressure of the SO 2 gas, indicating that dissociation of the hydrated form of adsorbed SO 2 is occurring on the surface. The H 2 O 2 uptakes scale linearly with the H 2 O 2 partial pressure, indicating that dissociation does not occur. The uptakes are driven by H-bond interactions in this case. Support for these conclusions comes from uptake measurements with ice surfaces which were formed by freezing either acidic or basic aqueous solutions. Although the H 2 O 2 uptakes are independent of pH, the acidic ice surfaces considerably inhibit the SO 2 uptake and the basic surfaces enhance the SO 2 uptake. The results in this paper are consistent with atmospheric observations which show that both S(IV) and H 2 O 2 have low retention efficiencies after supercooled cloud droplets freeze, whereas the retention efficiency of HNO 3 is high. The uptakes are sufficiently small that scavenging of SO 2 and H 2 O 2 by ice clouds will not be significant.

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