Letters.

MEDIEVAL ULCER MANAGEMENT SCIENTIFIC PAPERS SPECIAL EQUIPMENT IN NURSING HOMES TWO BANDAGING SYSTEMS SELECTION OF DRESSINGS FOR DIABETIC FOOT ULCERS.

Further studies using X-ray fluorescence to sample lead contaminated carpeted surfaces.

The sampling of carpeted surfaces to test for lead contamination primarily focuses upon vacuum techniques. Vacuum sampling techniques, however, require time-consuming, expensive laboratory analysis of the dusts obtained and are unable to determine total lead load on the carpet. X-ray fluorescence (XRF) analysis is an on-site, inexpensive, non-destructive, quick technique for predicting metals levels in a variety of media, such as water, soil, filter paper and painted surfaces. A 1992 study of the feasibility of XRF to analyze for lead and soil loadings on carpeted surfaces indicated that XRF can detect lead at a low enough level to warrant further study. This paper expands this earlier study and developes lead and soil loading calibration curves for three different carpet types based upon XRF lead L-beta peak areas and XRF iron and barium K-alpha peak and background areas. Results indicate that variation in the data can be reduced through modifications of the XRF analysis technique, thus reducing the statistically determined detection level, and that carpet type does affect the calibration. Detection levels of approximately 70 mg/m(2) for lead and 5 g/m(2) for soil were obtained. Overall, good agreement was found between results of this study and the earlier one. XRF shows excellent potential for quantitative analysis of lead on carpeted surfaces.

The use of X-ray fluorescence to detect lead contamination of carpeted surfaces.

The recognition of the hazards to young children of low-level lead intoxication and the widespread distribution of lead in the urban environment have resulted in massive federal, state, and local lead awareness and abatement programs. Two of the most significant exposure routes of lead to young children are the soils and dusts found within the child's home. Most state and federal lead abatement programs deal with lead-based paint contamination but often do not address the issue of soft-surface contamination, such as that of carpets, furniture, and draperies. Carpets can be a reservoir of contaminated soils and dusts; currently, there exists no standard method to test carpeted surfaces for lead contamination.This paper describes a study that uses X-ray fluorescence (XRF) to test carpeted surfaces for lead contamination. XRF technology is the standard technology used in lead-based paint testing and is known to be an accurate technique to test for lead in soils. This study uses a controlled laboratory atmosphere to evaluate this technology; the objectives are to determine: (1) a lower limit of detection for the instrument; and (2) whether soil loading levels can be differentiated by XRF using trace elements also present in the soil. Results indicate that XRF can easily differentiate soil loading levels (g soil/m(2) carpet). The lower limit of detection of soil lead concentration on the carpet is a function of both soil lead concentration and soil loading; therefore, lead loading (mg Pb/m(2)) is a better indicator of detection limit than soil lead concentration. Lead loading detection levels from 108-258 mg Pb/m(2) were obtained, as compared to a level of 10 000 mg/m(2) (1 mg/cm(2)) for lead on painted surfaces as required by theLead-Based Paint Poisoning Prevention Act.XRF technology has the potential to be a fast, inexpensive screening technique for the evaluation of lead contamination on carpeted surfaces.

Composition of the mount st. Helens ashfall in the moscow-pullman area on 18 may 1980.

Mineralogical and chemical analyses of the ashfall from Mount St. Helens on 18 May 1980 indicate that there were two distinct ashes. The early dark ash is composed principally of plagioclase and lithic fragments of plagioclase and glass with titanium-rich magnetite and some basaltic hornblende and orthopyroxene. The later pale ash, four-fifths by weight of the whole fallout, is 80 percent glass with plagioclase as the principal crystalline phase. Quartz and potassium feldspar are rare to absent in both ashes. Chemical analyses of nine ash fractions and of the glass in each type emphasize the differences between the two ash types and their chemical homogeneity.

Streptococcal pharyngitis in children. A comparison of four treatment schedules with intramuscular penicillin G benzathine.

Four hundred children with streptococcal pharyngitis were treated randomly with single injections in groups of 100 each (1) with 600,000 units of penicillin G benzathine, (2) 1.2 million units of penicillin G benzathine, (3) 600,000 units of penicillin G benzathine and 600,000 units of penicillin G procaine, or (4) 900,000 units of penicillin G benzathine and 300,000 units of penicillin G procaine. Clinical response and severity of local reaction were judged in a double-blind manner at 24, 48, and 72 hours; throat cultures were taken then, and at 10, 21, and 42 days. Although the clinical response to 900,000 units of penicillin G benzathine and 300,000 units of penicillin G procaine was equal to 1.2 million units of penicillin G benzathine, the former cleared the streptococci more quickly, greatly reduced the incidence and severity of local reactions, and offered optimal therapy for streptococcal pharyngitis in the pediatric age group.