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Arsenic contamination is of great environmental concern due to its toxic effects as a carcinogen. Knowledge of arsenic background concentrations is important for land application of wastes and for making remediation decisions. The soil clean-up target level for arsenic in Florida (0.8 and 3.7 mg kg−1 for residential and commercial areas, respectively) lies within the range of both background and analytical quantification limits. The objective of this study was to compare arsenic distribution in urban and non-urban areas of Florida. Approximately 440 urban and 448 non-urban Florida soil samples were compared. For urban areas, soil samples were collected from three land-use classes (residential, commercial and public land) in two cities, Gainesville and Miami. For the non-urban areas, samples were collected from relatively undisturbed non-inhabited areas. Arsenic concentrations varied greatly in Gainesville, ranging from 0.21 to approximately 660 mg kg−1 with a geometric mean (GM) of 0.40 mg kg−1, which were lower than Miami samples (ranging from 0.32 to 112 mg kg−1; GM=2.81 mg kg−1). Arsenic background concentrations in urban soils were significantly greater and showed greater variation than those from relatively undisturbed non-urban soils (GM=0.27 mg kg−1) in general. [Copyright &y& Elsevier]

Focuses on weathering of lead bullets and its effect on the environment at several outdoor shooting ranges in Florida. Analysis of soil, plant and water samples; Presence of hydrocerussite in the weathered crusts and berm soils in the shooting ranges with alkaline soil hydrogen-ion concentration; Observation of elevated total lead concentrations in bermudagrass and in surface water.

Investigates taxonomic and geographic distribution of total phosphorus (P) in Florida surface soils. Distribution characteristics of P concentration; Taxonomic distribution of total P concentrations in disturbed and undisturbed soils; Impact of anthropogenic input of total P concentrations in soils.

Background concentrations of soil arsenic have been used as an alternative soil cleanup criterion in many states in the U.S. This research addresses issues related to the interpretation of background concentrations of arsenic in near pristine soils in Florida. Total arsenic was measured in 448 taxonomic and geographic representative surface soil samples using USEPA Method 3052 (HCl-HNO 3 -HF, microwave digestion) and graphite furnace atomic absorption spectrophotometry analysis procedure. Values were log-normally distributed, with geometric mean and baseline concentration (defined as 95% of the expected range of background concentrations) providing the most satisfactory statistical results. An upper baseline concentration of 6.21 mg As/kg was estimated for undisturbed soils (n=267) compared to 7.63 mg As/kg for disturbed soils (n=181). Temporal trend of total soil arsenic concentrations from 1967 to 1989 paralleled decreased usage of arsenic in U.S. agriculture. Soil arsenic background concentrations were generally higher in south Florida than in north and central Florida, and associated with wet soils. Individual high arsenic sites were scattered throughout the state, but the most highly concentrated of these occurred in the Leon-Lee belt along the Ocala uplift district extending to the southwestern flatwoods district. Extrapolation of the data using a single arsenic value regardless of the taxonomic and geographical differences in soil arsenic distribution would underestimate potential arsenic contamination in upland soils. [ABSTRACT FROM AUTHOR]

Reports on issues discussed by a panel of academic, industry and regulatory scientists on the resolution of arsenic background concentrations in Florida. Anonymity regarding specific sample locations; Vertical sampling issues; Data evaluation; Censorship of data sets; Florida Legislature's order for the Florida Department of Environmental Protection to develop rules for site rehabilitation incorporating risk-based corrective action principles.

Compares the accuracy and precision of three aqua regia digestion methods in determining concentrations of different elements found in 20 Florida soils using the National Institute of Standards and Technology's standard reference materials. Variations in properties of soil samples; Spectrophotometric analysis of elemental concentration in the digestion solution; Disadvantage of conventional aqua regia digestion procedures.

Announces the discovery that the fern Pteris vittata (brake fern) is extremely efficient in extracting arsenic from soils and translocating it into its above-ground biomass. Importance of its role as an arsenic hyperaccumulator, and as the first fern found to function as a hyperaccumulator; Study of brake fern growing on a site in central Florida contaminated with chromated copper arsenate; Implications for the remediation of arsenic-contaminated soils and for the study of arsenic in plants.

The objective of this study was to establish baseline concentrationsfor 15 potentially toxic elements (Ag, As, Ba, Be, Cd, Cr, Cu, Hg, Mn, Mo, Ni, Ph, Sb, Se, and Zn) based on 448 representative Florida surface soils using microwave assisted HNO3-HCI-HF digestion. Baseline concentrations of those elements were (mg kg-1): Ag 0.072.50, As 0.02-7.01, Ba 1.67-112, Be 0.04-4.15, Cd 0-0.33, Cr0.89-80.7, Cu 0.22-21.9, Hg 0.00075-0.0396, Mo 0.13-6.76, Ni 1.70-48.5, Ph 0.6942.0, Sb 0.06-0.79, Se 0.01-1.11, and Zn 0.89-29.6, respectively. Upper baseline values for most elements corresponded with these reported in literature, except Ba, Hg, Mn, Sb, and Zn, which were 3 to 23 times lower. Soil properties, including pH, organic carbon (OC), particle size, cation-exchange capacity (CEC), available water, extractable base, extractable acidity, total Ca, Mg, P, K, Fe, and A1 concentrations, were related to metal concentrations using factorial analysis. Eight factors were identified (total Fe and AI, CEC, pH, clay, OC, total Ni and Mo, total Sb and Pb, and total Hg) and accountedfor 87% of the total variance, suggesting that metal concentrations were primarily controlled by soil compositions. Multiple regression of elemental concentrations against total Fe, total AI, clay, OC, CEC,and pH was significant for all elements. Partial correlation coefficients indicated that total Fe and/or AI explained most of the variance for Mn, Ni, Ba, Be, Hg, As, Cd, Cr, Cu, Mo, Pb, and Zn concentrations. Most of the variance in Se was related to clay, whereas those of Ag and Sb related to clay and total AI. [ABSTRACT FROM AUTHOR]