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Prior to Hurricanes Katrina and Rita (HKR), significant associations were noted between soil lead (SL) and blood lead (BL) in New Orleans. Engineering failure of New Orleans levees and canal walls after HKR set the stage for a quasi-experiment to evaluate BL responses by 13 306 children to reductions in SL. High density soil surveying conducted in 46 census tracts before HKR was repeated after the flood. Paired t test results show that SL decreased from 328.54 to 203.33 mg/kg post-HKR (t = 3.296, por = 0.01). Decreases in SL are associated with declines in children's BL response (r = 0.308, por = 0.05). When SL decreased at least 1%, median children's BL declined 1.55 microg/dL. Declines in median BL are largest in census tracts withor =50% decrease in SL. Also individual BL in children was predicted as a function of SL, adjusting for age, year of observation, and depth of flood waters. At the individual scale, BL decreased significantly in post-HKR as a function of SL, with BL decreases ranging from b = -1.20 to -1.65 microg/dL, depending on the decline of SL and whether children were born in the post-HKR period. Our results support policy to improve soil conditions for children.

The inputs and outputs of airborne lead in the South Coast Air Basin of California (SOCAB) are quantified according to standard mass balance calculations. Results for 2001 show that approximately 49,000 kg of lead exitthe Basin each year, but traditional sources contribute only about 6500 kg of lead each year. We resolve this discrepancy through a simple computer model that quantifies the resuspension of lead-containing particles. Our results suggest that these lead particles were deposited during the years of leaded gasoline use and that resuspension is responsible for generating an additional 54,000 kg of airborne lead each year. This agrees roughly with estimated outputs. Thus, we conclude that resuspension, although an insignificant source of airborne lead during the era of leaded fuel, became a principal source in the SOCAB as lead emissions from vehicles declined. The results of the resuspension model further suggest that soil lead levels will remain elevated for many decades, in which case resuspension will remain a major source well into the future.

In and around well-kept homes painted with low lead paints situated in a small urban community, large amounts of lead and cadmium are found. High trace metal amounts are also found at nonresidential sites. Much of the lead is probably of automotive origin. Lead levels in dusts within homes average 600 ppM and 680 ..mu..g/m/sup 2/. In nonresidential interiors, dusts average 1400 ppM Pb and 2040 ..mu..g Pb/m/sup 2/. Unexpectedly high cadmium accumulations are found, especially in carpet dusts from rubber-backed carpets. High nonresidential settled dust and soil lead contents are due to higher traffic flows. The lead content of outdoor residential dust is 600-1950 ppM and 90-6640 ..mu..g/m/sup 2/. These values increase several times around nonresidential sites. Lead and cadmium from trace urban dusts are a significant addition to the child body burden.

A paper by Schuck and Locke is discussed and evaluated. The author's conclusions are that the authors presented good evidence supporting their thesis that particulate lead from automobile exhaust contaminates crops growing in the vicinity of high traffic density roadways. Their contention that this contamination is entirely a surface coating is not well substantiated. Some of the results are inconclusive and others suggest a surface adsorption or the absorption of some lead into the plant parts studied. The possibility of the uptake of lead from soils is not eliminated. Soil lead levels in the vicinity of high traffic density highways could eventually become of concern. Although lead appears to be immobile in the soils, some work suggests that the lead does become available to some crops at certain high concentrations.