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Hexavalent chromium is a common skin irritant that can cause contact dermatitis in sensitized individuals. Soil samples from two chromium waste sites having different Cr(VI) concentrations were extracted in synthetic sweat solutions over a pH range of 4 to 8 and analyzed for Cr(VI). These extractions were performed to determine the potential availability of Cr(VI) from contaminated soils upon contact with human sweat. The samples were also extracted using the EPA Method 3060 alkaline digestion. Overall, hexavalent chromium was readily extractable from both samples in the solutions tested. One of the samples contained Cr(VI) crystals, known as blooms, and had a Cr(VI) concentration approximately 40 times greater than the sample without blooms. The pH of the synthetic sweat solution had little effect on the Cr(VI) concentration determined for the sample containing blooms, whereas the Cr(VI) concentration determined for the sample without blooms increased with increasing pH. The Cr(VI) extracted in the synthetic sweat solutions was consistently lower than the amount extracted by the EPA 3060 alkaline extraction.

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Although hexavalent chromium, Cr(VI), is a potent sensitizer and inducer of allergic contact dermatitis and is found in many common materials, no standard or guideline currently exists for protection against these effects in environmental exposure. There appears to be a generalized allergenic potential among the various compounds of Cr(VI). Estimates of the prevalence of Cr sensitivity in the population are uncertain, but range from about 2% of the total population in Finland to as high as 20% in U.S. populations with a dermatitis. Based on the thresholds reported for nine separate patch-test studies and statistical analysis of the aggregate dose-response relationship from 72 separate observations from these studies and on studies of allergic responses to bleaches and detergents, the effective threshold for elicitation of allergic contact dermatitis in sensitized populations is about 10 ppm (mg/L) Cr(VI) (as chromium) in solution. Based on evaluation of the literature on cement dermatitis, the threshold concentration of extractable Cr(VI) in solid material may be as low as 10 ppm (microgram/g). For ingestion of Cr(VI), the lowest observed effect level (LOEL) dose for elicitation is 0.26 microgram/kg. In calculating the threshold concentration of Cr(VI) in soil for elicitation of contact dermatitis, extractability must be taken into account.

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Eighty-six liver samples were collected from hunter-killed deer at various locations in New Jersey and analysed for cadmium. Concentrations ranged from 0.07 to 23.2 micrograms/g dry weight. Three of the highest concentrations were measured in samples collected from an area with known cadmium contamination resulting from past waste disposal practices. Significant differences in liver cadmium concentration were noted among deer from different areas (p less than 0.01) and among different age groups (p less than 0.01). No sex-related differences were observed (p = 0.48). A survey of deer liver consumption was conducted and the data were used in formulating a health advisory. The lack of knowledge about the effects of cadmium on wildlife health is discussed in relation to an expected increase in the land disposal of sewage.

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A literature review of experimental and human exposure studies of skin permeation and cutaneous hypersensitivity reactions evoked by chromium was carried out to provide a basis for making a risk assessment of chromium as a soil contaminant. In vitro and in vivo studies demonstrated that 1 to 4% of the applied dose of hexavalent and trivalent chromium to guinea pig skin penetrated skin within 5 to 24 hr after application. Ultrastructural investigations showed that hexavalent chromium localized intracellularly and extracellularly in the upper layers of guinea pig epidermis. Only minute quantities of hexavalent chromium are required to elicit a positive hypersensitivity reaction in susceptible individuals; using a patch dose of 20 micrograms, only 2 micrograms were required to evoke a positive skin reaction in hypersensitive subjects. The potential of hexavalent chromium to produce a skin sensitization reaction is readily demonstrated using animal models. The incidence and characteristics of chromium-induced skin hypersensitivity as a clinical entity are described. A health effects survey of populations exposed to chromium slag in soil in Tokyo, Japan extending over 8 years indicated a tendency toward symptoms characterized as headache, chronic fatigue, and gastrointestinal complaints, positive occult blood tests, minute hematuria and albuminuria suggestive of incipient renal disease, and a tendency toward an increase in contact dermatitis that was seasonally related. Multicenter patch test titration studies in human subjects using an incidence of positive patch tests of 10% or less showed that the threshold for skin hypersensitivity reactions to hexavalent chromium was determined to be of the order 0.001%, equivalent to 10 ppm or 10 mg/kg or 10 mg/L.(ABSTRACT TRUNCATED AT 250 WORDS)

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Chromite ore processing residue occurs at over 130 sites in Hudson County, New Jersey. Many of these sites are in urban residential areas. This waste is a result of 70 years of chromate and bichromate chemical manufacturing. At least 15% of the sites contain total chromium concentrations greater than 10,000 mg/kg, with hexavalent content ranging from about 1 to 50%. Continuing leaching of this waste results in yellow-colored surface water runoff and yellow deposits on the soil surface and inside basement walls. The chemistry, environmental fate, health effects, and human exposure potentials for this waste are described.

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The study reported here presents the results of an investigation of a marsh-cove ecosystem heavily contaminated by cadmium. The most contaminated aquatic sediments were dredged in 1972-73, but the resuspension of the sediments and recycle of water from the dredge spoil resulted in reestablishment of a large contaminated sediment bed with concentrations very similar to those observed before dredging. The stability of the sediment concentrations and shallow depth of the cadmium in the sediments indicate that the deposit is relatively stable in agreement with the expectations based on the water chemistry of the system. Uptake does occur in both marsh and aquatic plants and all species of animals tested. Significantly elevated concentrations are observed compared to noncontaminated areas; however, edible portions of most fish do not appear to present a hazard. Crabs appear to present the most likely source of a hazard to humans. This potential hazard is still under investigation. The dredging removed about 5.5 MT of cadmium, about one-fourth of that originally estimated to be present, but twice that amount is found to be in the cove sediments 3 to 4 years after dredging. No appreciable improvement in the ecosystem has been made, and more careful consideration should be given to the need for decontamination and the method of removal of contaminated aquatic sediments in any future case.

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