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In the present study, the distribution patterns of various metals were analyzed and compared using PM samples collected concurrently from three monitoring sites located in Korea (Seoul, Busan, and Jeju island) in December 2002. As these sites can represent metal pollution with different degrees of anthropogenic activities, their concentration levels were distinguished in a systematic manner in the order of Jeju, Busan, and Seoul. By comparing the present data sets with those measured previously from other locations in Korea and around the world, we attempted to diagnose the general status of elemental pollution on the Korean peninsula. Through an application of different statistical approaches, the major processes controlling elemental levels were assessed for each of the three study sites. The results indicated the importance of both crustal and anthropogenic sources in all sites with their relative roles varying significantly from each other. The results of the metal analysis data, when examined in relation to back trajectory analysis, confirmed that their concentration changes are affected quite sensitively with air mass movement patterns. The overall results of this study consistently indicated the contribution of a strong anthropogenic source area (e.g., China) to the observed metal concentration levels in the study area, but the strengths of such signals vary considerably across the Korean peninsula. [ABSTRACT FROM AUTHOR]

The safety and long-term effectiveness of fluoroscopically guided balloon dilation for corrosive esophageal stricture was evaluated in 22 patients with a follow-up period of more than 1 year (range, 13-52 months). The average interval between corrosive agent ingestion and initial balloon dilation was 18 years (range, 2 months to 51 years). Balloons with a diameter of 5-8 mm were used in the initial attempt. The caliber of the balloon catheter was increased gradually over subsequent dilations, up to a diameter that allowed patients to swallow solid foods. Dilation of more than 17 mm in diameter was performed in five patients. Patients underwent one to five sessions. Esophageal rupture occurred in seven patients and was treated nonoperatively in five and surgically in two. With exclusion of these latter two, 11 of 20 could tolerate swallowing all kinds of food and nine could tolerate swallowing most foods. Balloon dilation in corrosive esophageal strictures is effective, but the high rupture rate indicates the need for extra caution.