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Occurrence of perfluorooctane sulfonate (PFOS) in the tissues of humans and wildlife is well documented. In this study, concentrations and distribution of PFOS, perfluorohexane sulfonate (PFHS), and perfluorobutane sulfonate (PFBS) were determined in samples of surface water, fish and bird blood and livers, and human blood collected in Japan. Notable concentrations of PFOS were found in surface water and fish from Tokyo Bay. PFOS was found in all of the 78 samples of fish blood and liver analyzed. Based on the concentrations of PFOS in water and in fish livers, bioconcentration factors were calculated to range from 274 to 41 600. Concentrations of PFOS in the blood of Japanese human volunteers ranged from 2.4 to 14 ng/mL. PFHS was detected in 33% of the fishes analyzed, at concentrations severalfold less than those of PFOS.

The determination of organosiloxanes in consumer products is important for the evaluation and characterization of sources of human and environmental exposures. In this study, we determined concentrations of cyclic siloxanes [octamethylcyclotetrasiloxane (D(4)), decamethylcyclopentasiloxane (D(5)), dodecamethylcyclohexasiloxane (D(6))], tetradecamethylcycloheptasiloxane (D(7))] and linear siloxanes (L(4) to L(14)) in a variety of consumer products (n = 76), including hair-care products, skin lotions, body washes, cosmetics, nursing nipples (i.e., pacifiers), cookware, and household sanitation products such as cleansers and furniture polishes, using gas chromatography-mass spectrometry with selected ion monitoring. Prior to the analysis of samples, a method was developed to reduce the contamination arising from organosiloxanes present in certain gas chromatograph (GC) parts, such as the inlet septum; use of a Restek BTO septum at an inlet temperature of 200 degrees C gave the lowest background level (D(4): 0.8 pg; D(5): 0.3 pg; D(6): 0.2 pg). Concentrations of cyclic siloxanes in consumer products analyzed ranged from <0.35 to 9380 microg/g, from <0.39 to 81,800 microg/g, from <0.33 to 43,100 microg/g, and from <0.42 to 846 microg/g for D(4), D(5), D(6), and D(7), respectively. Concentrations of linear siloxanes varied from <0.059 to 73,000 microg/g. More than 50% of the samples analyzed contained D(4), D(5), or D(6). Cyclic siloxanes were predominant in most of the sample categories; D(5) was predominant in hair-care products, skin lotions, and cosmetics; D(6) or D(7) was predominant in rubber products, including nipples, cookware, and sealants. Potential daily exposure to total organosiloxanes (sum of cyclic and linear siloxanes) from the use of personal-care products by adult women in the United States has been estimated to be 307 mg. Significant positive correlations (p < 0.01) existed in our study between D(4) and D(7), D(4) and linear siloxanes, D(5) and D(6), and D(5) and linear siloxanes. The correlations can be related to the composition of organosiloxanes used in consumer products. The results of our study suggest that a wide variety of consumer products that are used on a daily basis contain cyclic and linear siloxanes and these products can contribute considerably to human exposures.

Perfluorinated acids (PFAs) and their salts have emerged as an important class of global environmental contaminants. Determination of sub-parts-per-trillion or parts-per-quadrillion concentrations of perfluorinated acids in aqueous media has been impeded by relatively high background levels arising from procedural or instrumental blanks. To understand the role of the oceans in the transport and fate of perfluorinated acids, methods to determine ultratrace levels of these compounds in seawater are needed. In this study, sources of procedural and instrumental blank contamination by perfluorinated acids have been identified and eliminated, to reduce background levels in blanks and thereby improve limits of quantitation. The method developed in this study is capable of detecting perfluorooctanesulfonate (PFOS), perfluorohexanesulfonate (PFHS), perfluorobutanesulfonate (PFBS), perfluorooctanoate (PFOA), perfluorononanoate (PFNA), and perfluorooctanesulfonamide (PFOSA) at low pg/L levels in oceanic waters. PFOA is the major perfluorinated compound detected in oceanic waters, followed by PFOS. Further studies are being conducted to elucidate the distribution and fate of perfluorinated acids in oceans.

Chlorinated polycyclic aromatic hydrocarbons (CIPAHs) have been reported to occur in urban air. Nevertheless, sources of CIPAHs in urban air have not been studied, due to the lack of appropriate analytical methods and standards. In this study, we measured concentrations of 20 CIPAHs and 11 brominated PAHs (BrPAHs) in fly ash and bottom ash from 11 municipal/hazardous/industrial waste incinerators, using analytical standards synthesized in our laboratory. Concentrations of total CIPAHs and BrPAHs in ash samples ranged from <0.06 to 6990 ng/g and from <0.14 to 1235 ng/g, respectively. The concentrations of CIPAHs were approximately 100-fold higher than the concentrations of BrPAHs. 6-CIBaP and 1-CIPyr were the dominant compounds in fly ash samples. The profiles of halogenated PAHs were similar to the profiles reported previously for urban air. 1-BrPyr was the predominant BrPAH in fly ash. Concentrations of 6-CIBaP, 9,10-Cl2Phe, 9-CIAnt, and 6-BrBaP in fly ash were significantly correlated with the corresponding parent PAH concentrations. Significant correlation between sigmaCIPAH and sigmaPAH concentrations suggests that direct chlorination of parent PAHs is the mechanism of formation of CIPAHs during incineration of wastes; nevertheless, a comparable correlation was not found for BrPAHs. There was no significant correlation between the capacity and temperature of an incinerator and the concentrations of sigmaCl-/BrPAHs in ash samples, although lower concentrations of all halogenated PAHs were found in stoker-type incinerators than in fixed grate-type incinerators. Toxicity equivalency quotients (TEQs) for CIPAHs in ash samples were calculated with CIPAH potencies. Average TEQ concentrations of CIPAHs in fly ash and bottom ash were15800 pg-TEQ/g and 67 pg-TEQ/g, respectively. Our results suggest that the extent of dioxin-like toxicity contributed by CIPAHs in ash generated during waste incineration is similar to that reported previously for dioxins. Waste incineration is an important source of Cl-/BrPAHs in the urban atmosphere.

The partitioning behavior of per- and polyfluoroalkyl compounds (PFCs) between pore water and sediment in two sediment cores collected from Tokyo Bay, Japan, was investigated. In addition, the fluxes and temporal trends in one dated sediment core were studied. Short-chain perfluoroalkyl carboxylic acids (PFCAs) (C < or = 7) were found exclusively in pore water, while long-chain PFCAs (C > or = 11) were found only in sediment The perfluoroalkyl sulfonates (PFSAs), n-ethylperfluoro-1-octanesulfonamidoacetic acid (N-EtFOSAA), and perfluorooctane sulfonamide (PFOSA) seemed to bind more strongly to sediment than PFCAs. The enrichment of PFCs on sediment increased with increasing organic matter and decreasing pH. The perfluorocarbon chain length and functional group were identified as the dominating parameters that had an influence on the partitioning behavior of the PFCs in sediment The maximum SigmaPFC contamination in sediment was observed in 2001-2002 to be a flux of 197 pg cm(-2) yr(-1). Statistically significant increased concentrations in Tokyo Bay were found for perfluorooctanesulfonate (PFOS) (1956-2008), perfluorononanoic acid (PFNA) (1990-2008), and perfluoroundecanoic acid (PFUnDA) (1990-2008). Concentrations of PFOSA and N-EtFOSAA increased between 1985 and 2001, but after 2001, the concentration decreased significantly, which corresponded with the phase out of perfluorooctyl sulfonyl fluoride-based compounds by the 3M Company in 2000.

The widespread distribution of perfluorinated chemicals (PFCs) in different environmental matrices has prompted concern about the sources, fate, and transport of these classes of chemicals. PFCs are present in the atmosphere, but only a few studies have investigated their occurrence in precipitation. In this study, concentrations of 20 PFCs, including C3-C5 short-chain PFCs, were quantified using HPLC-MS/MS in precipitation samples from Japan (n = 31), the United States (n = 12), China (n = 5), India (n = 2), and France (n = 2). Among the PFCs measured, perfluoropropanoic acid (PFPrA) was detected in all of the precipitation samples. Average total PFC concentrations ranged from 1.40 to 18.1 ng/L for the seven cities studied. The greatest total PFC concentrations were detected in Tsukuba, Japan, whereas the lowest concentrations were detected in Patna, India. PFPrA, perfluorooctanoic acid (PFOA), and perfluorononanoic acid (PFNA) were found to be the dominant PFCs in Japanese and U.S. precipitation samples. No observable seasonal trend was found in precipitation samples from two locations in Japan. Annual fluxes of PFCs were estimated for Japan and the U.S. and the evidence for precipitation as an effective scavenger of PFCs in the atmosphere is reported.

Organic semiconductors may be processed in solution under ambient conditions; however, liquid manipulation on hydrophobic surfaces is difficult, which may hinder development of devices. Here, a push-coating technique is used to produce large-area semiconducting polymer films over hydrophobic surfaces.