Maps of Minnesota (A) and California (B and C) sampling locations.

<p>(A) East Gemini Lake, Lake St. Croix, and Lake Pepin in Minnesota; (B) Point Reyes National Seashore, CA, and (C) 2000 census population density for the San Francisco Bay region generated by Dasymetric (ArcGIS10x) software courtesy of the U.S. Geological Survey with wastewater outfalls (black circle) and surface sediments, cores, and surface waters collection sites (black triangles).</p

Chemical structures of OH-BDEs, PBDEs, triclosan, and polyhalogenated dibenzo-<i>p</i>-dioxins (PXDDs).

<p>Chemical structures of OH-BDEs, PBDEs, triclosan, and polyhalogenated dibenzo-<i>p</i>-dioxins (PXDDs).</p

Concentration of triclosan, 2,8-DiCDD, 6-OH-BDE 47, and 1,3,7-TriBDD in three sediment cores (A, B, & C) at Point Reyes National Seashore.

<p>ND denotes analyte levels below LOD</p><p>^a Final depth for core ‘C’ is 16 cm</p><p>^b Concentration > LOD and < LOQ</p><p>^c OH-BDEs with concentrations < LOD are not shown, includes: 6-OH-BDE 90, 6-OH-BDE 99, 6’-OH-BDE 100, and 6’-OH-BDE 118</p><p>^d PBDDs with concentrations < LOD are not shown, includes: 1,2,4,7/1,2,4,8-TeBDD, and 2,3,7,8-TeBDD</p><p>Concentration of triclosan, 2,8-DiCDD, 6-OH-BDE 47, and 1,3,7-TriBDD in three sediment cores (A, B, & C) at Point Reyes National Seashore.</p

Quantification of Hydroxylated Polybrominated Diphenyl Ethers (OH-BDEs), Triclosan, and Related Compounds in Freshwater and Coastal Systems

<div><p>Hydroxylated polybrominated diphenyl ethers (OH-BDEs) are a new class of contaminants of emerging concern, but the relative roles of natural and anthropogenic sources remain uncertain. Polybrominated diphenyl ethers (PBDEs) are used as brominated flame retardants, and they are a potential source of OH-BDEs via oxidative transformations. OH-BDEs are also natural products in marine systems. In this study, OH-BDEs were measured in water and sediment of freshwater and coastal systems along with the anthropogenic wastewater-marker compound triclosan and its photoproduct dioxin, 2,8-dichlorodibenzo-<i>p</i>-dioxin. The 6-OH-BDE 47 congener and its brominated dioxin (1,3,7-tribromodibenzo-<i>p</i>-dioxin) photoproduct were the only OH-BDE and brominated dioxin detected in surface sediments from San Francisco Bay, the anthropogenically impacted coastal site, where levels increased along a north-south gradient. Triclosan, 6-OH-BDE 47, 6-OH-BDE 90, 6-OH-BDE 99, and (only once) 6’-OH-BDE 100 were detected in two sediment cores from San Francisco Bay. The occurrence of 6-OH-BDE 47 and 1,3,7-tribromodibenzo-<i>p</i>-dioxin sediments in Point Reyes National Seashore, a marine system with limited anthropogenic impact, was generally lower than in San Francisco Bay surface sediments. OH-BDEs were not detected in freshwater lakes. The spatial and temporal trends of triclosan, 2,8-dichlorodibenzo-<i>p</i>-dioxin, OH-BDEs, and brominated dioxins observed in this study suggest that the dominant source of OH-BDEs in these systems is likely natural production, but their occurrence may be enhanced in San Francisco Bay by anthropogenic activities.</p></div

Limits of detection and quantification for triclosan and OH-BDEs in water (ng/L) and sediment (pg/g) samples.

<p>*Not detected in sample, LOQ was determined by lowest concentration of the calibration curve</p><p>Limits of detection and quantification for triclosan and OH-BDEs in water (ng/L) and sediment (pg/g) samples.</p

Concentrations of triclosan, PBDEs, 6-OH-BDE 47, and PXDDs in San Francisco Bay sediments and salinity in surface waters.

<p>^a Sample IDs are those used by SFEI for these sampling locations in their Regional Monitoring Program</p><p>^b San Francisco Estuary Institute [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0138805#pone.0138805.ref075" target="_blank">75</a>]</p><p>^c OH-BDEs with concentrations < LOD are not shown, includes: 6-OH-BDE 90, 6-OH-BDE 99, 6’-OH-BDE 100, and 6’-OH-BDE 118</p><p>^d PBDDs with concentrations < LOD are not shown, includes: 1,2,4,7/1,2,4,8-TeBDD, and 2,3,7,8-TeBDD</p><p>^e Concentration > LOD and < LOQ</p><p>^f Measured at nearby sites, see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0138805#pone.0138805.s010" target="_blank">S4 Table</a>.</p><p>ND denotes concentration < LOD</p><p>N/A denotes a sample that was not analyzed for a specific compound.</p><p>Concentrations of triclosan, PBDEs, 6-OH-BDE 47, and PXDDs in San Francisco Bay sediments and salinity in surface waters.</p

Absolute recovery (%) of isotope labeled compounds in sediment and water matrices in <i>n</i> number of samples.

<p>Absolute recovery (%) of isotope labeled compounds in sediment and water matrices in <i>n</i> number of samples.</p

Concentrations (ng/L) of triclosan and OH-BDEs in surface waters.

<p>^<i>a</i> One replicate > LOD and < LOQ, with other replicates < LOD.</p><p>^<i>b</i> One replicate >LOQ, two replicates >LOD and </p><p>ND denotes concentration < LOD.</p><p>Concentrations (ng/L) of triclosan and OH-BDEs in surface waters.</p

Relative recovery (%) of analytes in sediment and water.

<p>Relative recovery (%) of analytes in sediment and water.</p

Concentration profiles of OH-BDEs and triclosan in sediment cores.

<p>(A) Central Bay, CA and (B) South Bay, CA. Profiles are given for 6-OH-BDE 47 (blue triangle), 6-OH-BDE 90 (yellow diamond), 6-OH-BDE 99 (green square), and triclosan (black circle). Italicized dates are approximate years determined by ²¹⁰Pb.</p