Applicability and limitations of the radon-deficit technique for the preliminary assessment of sites contaminated with complex mixtures of organic chemicals: A blind field-test.

A blind field test with 136 independent measurements of radon (222Rn) in soil air retrieved from a depth of 0.8 m in a decommissioned lindane (γ-hexachlorocyclohexane) production plant was undertaken to evaluate the performance of the 222Rn-deficit technique as a screening methodology for the location and delineation of subsurface accumulations of complex mixtures of organic contaminants. Maps of 222Rn iso-concentrations were drawn and interpreted before direct analytical information regarding concentrations of hexachlorocyclohexanes, chlorobenzenes and BTEX compounds in soil, groundwater and soil air were disclosed to the authors. The location and extension of pollution hot spots inferred from the 222Rn campaigns agrees remarkably well with the analytical data obtained from the intrusive sampling campaigns and with the location of contaminant source zones (chemical reactor and waste-storage area) and geological sinks of those contaminants (paleochannel). Two main limitations to the applicability of the 222Rn-deficit technique were identified and assessed: The statistically significant variation of 222Rn concentrations with diurnal changes of ground-level air temperature and the maximum depth of investigation in the absence of significant advective and co-advective transport of radon. If the influence of those two factors is accounted for and/or minimized (by averaging replicated measurements during the workday and in different days), the 222Rn-deficit technique has the potential to be an efficient technique which delivers information in quasi-real time, with a much higher spatial density than that of intrusive techniques, at a much faster rate and at a significantly lower cost. MAIN FINDINGS: The 222Rn-deficit technique is an effective tool for real-time site characterization only limited by diffusion length of radon and diurnal temperature variations.

Environmental risk assessment of cobalt and manganese from industrial sources in an estuarine system.

A total of 74 samples of soil, sediment, industrial sludge, and surface water were collected in a Mediterranean estuarine system in order to assess the potential ecological impact of elevated concentrations of Co and Mn associated with a Terephthalic (PTA) and Isophthalic (PIPA) acids production plant. Samples were analyzed for elemental composition (37 elements), pH, redox potential, organic carbon, and CaCO3 content, and a group of 16 selected samples were additionally subjected to a Tessier sequential extraction. Co and Mn soil concentrations were significantly higher inside the industrial facility and around its perimeter than in background samples, and maximum dissolved Co and Mn concentrations were found in a creek near the plant's discharge point, reaching values 17,700 and 156 times higher than their respective background concentrations. The ecological risk was evaluated as a function of Co and Mn fractionation and bioavailability which were controlled by the environmental conditions generated by the advance of seawater into the estuarine system during high tide. Co appeared to precipitate near the river mouth due to the pH increase produced by the influence of seawater intrusion, reaching hazardous concentrations in sediments. In terms of their bioavailability and the corresponding risk assessment code, both Co and Mn present sediment concentrations that result in medium to high ecological risk whereas water concentrations of both elements reach values that more than double their corresponding Secondary Acute Values.

Antineutrophil cytoplasmic antibodies in systemic lupus erythematosus in childhood.

OBJECTIVE: Antineutrophil cytoplasmic antibodies (ANCA) have been found in up to 25% of adults with systemic lupus erythematosus (SLE) and in 69% of affected children. We investigated ANCA and antibodies to myeloperoxidase (MPO) in 50 children with SLE. METHODS: ANCA in serum were measured by indirect immunofluorescence and antibodies to MPO by ELISA. RESULTS: ANCA were found in 8 (7 perinuclear ANCA, 1 cytoplasmic ANCA) of the 50 sera tested (16%). All the 8 ANCA positive patients were also positive for anti-MPO antibodies. No association with vasculitis or specific organ involvement was observed. CONCLUSION: Our results in children are roughly similar to those reported for adults.

Phagocytic activity of circulating polymorphonuclear leukocytes from patients with carcinoma of the uterine cervix.

Peripheral blood leukocytes and the sera from 10 healthy women and 12 patients with invasive carcinoma of the cervix (stages I to IV), showed no differences in their capacity to inhibit the replication of an invasive strain of Escherichia coli. The serum from only one patient was unable to arrest the bacterial growth. The quantitation of myeloperoxidase in the polymorphonuclear leukocytes from 21 patients (stages I to III) and 11 healthy women showed, however, a lower activity in the group of patients (P = 0.001). Most patients also showed lymphocytopenia, neutrophilia, and eosinophilia but normal counts of total leukocytes.