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Perchlorate (ClO4−) is ubiquitous in the environment and inhibits the thyroid's uptake of iodide. Food and tap water are likely sources of environmental exposure to perchlorate. The aim of this study was to identify significant dietary sources of perchlorate using perchlorate measured in urine as an exposure indicator. Sample-weighted, age-stratified linear regression models of National Health and Nutrition Examination Survey (NHANES) 2001-2008 data (n=16,955 participants) characterized the association between urinary perchlorate and the mass consumed in USDA food groups, controlling for urinary creatinine and other potential confounders. Separate models of NHANES 2005-2006 data (n=2841) evaluated the association between urinary perchlorate and perchlorate consumed via residential tap water. Consumption of milk products was associated with statistically significant contributions to urinary perchlorate across all age strata: 2.93 ng ClO4−/ml per kg consumed for children (6-11 years-old (YO)); 1.54 ng ClO4−/ml per kg for adolescents (12-19 YO); and 0.69 ng ClO4−/ml per kg for adults (20-84 YO). Vegetables were a significant contributor for adolescents and adults, whereas fruits and eggs contributed significantly only for adults. Dark-green leafy vegetables contributed the most among all age strata: 30.83 ng ClO4−/ml per kg for adults. Fats, oils, and salad dressings were significant contributors only for children. Three food groups were negatively associated with urinary perchlorate: grain products for children; sugars, sweets, and beverages for adolescents; and home tap water for adults. In a separate model, however, perchlorate consumed via home tap water contributed significantly to adult urinary perchlorate: 2.11E-4 ng ClO4−/ml per ng perchlorate in tap water consumed. In a nationally representative sample of the United States 6-84 YO, diet and tap water contributed significantly to urinary perchlorate, with diet contributing substantially more than tap water. [ABSTRACT FROM AUTHOR]

Thirty-five strains of the Lyme disease spirochete Borrelia burgdorferi sensu lato (B. burgdorferi s. l.) were isolated from the blacklegged tick vector Ixodes scapularis in South Carolina, Georgia, Florida, and Rhode Island. They were characterized by PCR-restriction fragment length polymorphism (RFLP) analysis of rrf (5S)-rrl (23S) intergenic spacer amplicons. PCR-RFLP analysis indicated that the strains represented at least 3 genospecies (including a possible novel genospecies) and 4 different restriction patterns. Thirty strains belonged to the genospecies B. burgdorferi sensu stricto (B. burgdorferi s. s.), 4 southern strains were identified as B. bissettii, and strain SCCH-5 from South Carolina exhibited MseI and DraI restriction patterns different from those of previously reported genospecies. Complete sequences of rrf-rrl intergenic spacers from 14 southeastern and northeastern strains were determined and the phylogenetic relationships of these strains were compared. The 14 strains clustered into 3 separate lineages on the basis of sequence analysis. These results were confirmed by phylogenetic analysis based on 16S rDNA sequence analysis. [ABSTRACT FROM AUTHOR]

Presents a study on the molecular characterization of Borrelia isolates from ticks and mammals from the southern U.S. Use of genomic macrorestriction analysis; Determination of significant genetic diversity; Analysis of different isolates through restriction fragment length polymorphism and sequence analysis.

Abstract: Polycyclic musks, 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta[g]-2-benzopyran (HHCB) and 7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene (AHTN), are used as fragrance ingredients in numerous consumer products such as cleaning agents and personal care products. Studies have reported the widespread occurrence of these musks in surface waters and fish from western European countries. Nevertheless, little is known about their accumulation in humans and wildlife in the United States. In this study, we measured concentrations of HHCB and AHTN in human adipose fat collected from New York City. Furthermore, tissues from marine mammals, water birds, and fish collected from US waters were analyzed to determine the concentrations of HHCB and AHTN. Concentrations of HHCB and AHTN in human adipose fat samples ranged from 12 to 798 and from <5 to 134ng/g, on a lipid weight basis, respectively. A significant correlation existed between the concentrations of HHCB and AHTN in human adipose fat. Concentrations of HHCB and AHTN were not positively correlated with age or gender of the donors. HHCB was found in tissues of several wildlife species, but not in the livers of polar bear from the Alaskan Arctic. Among wildlife species analyzed, spinner and bottlenose dolphins collected from Florida coastal waters contained measurable concentrations of HHCB. [Copyright &y& Elsevier]