Collection of airborne fluorinated organics and analysis by gas chromatography/chemical ionization mass spectrometry
ABSTRACT The ubiquitous detection of perfluorooctane sulfonate (PFOS) in humans and animals has produced a need for sensitive and compound-specific analytical methods to determine the environmental distribution of fluorinated organic contaminants. A suite of potential PFOS precursors (sulfonamides) and fluorotelomer alcohols (FTOHs) were separated by gas chromatography and detected by chemical ionization mass spectrometry (GC/CI-MS). Full-scan spectra were collected in both positive and negative chemical ionization (PCI and NCI, respectively) mode to determine retention time windows and fragmentation patterns. In selected ion monitoring (SIM) mode, instrumental detection limits ranged from 0.2 to 20 pg for individual analytes, depending on ionization mode. PCI mode was preferred for routine analysis because of the simple mass spectra produced, typified by the presence of a major molecular ion [M + H]+. High-volume air samplers collected gaseous and particle-bound fluoroorganics on composite media consisting of XAD-2, polyurethane foam (PUF), and quartz-fiber filters. The combined collection efficiency for individual analytes was 87 to 136% in breakthrough experiments. Application of the method to the analysis of ambient air from urban and rural sites confirmed the presence of six novel fluorinated atmospheric contaminants at picogram per meter3 concentrations. Low concentrations of fluoroorganics were consistently detected in blanks (<4 pg m(-3)); however, this did not prevent confirmation or quantification of environmental concentrations.
- SourceAvailable from: Kung-Hui Chu
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- "FTOHs are volatile, not very soluble in water (carbon chain-length dependent) in the absence of a sorbing medium (Liu and Lee, 2005) and have a tendency to be adsorbed strongly to solid matters such as household dusts (Strynar and Lindstrom, 2008), soils or activated sludge (Liu and Lee, 2005, 2007; Wang et al., 2005a). Field monitoring studies have detected FTOHs in the troposphere at concentrations ranging from 7 to 196 pg/m 3 (Martin et al., 2002) and averaged 87 pg/m 3 (Dreyer et al., 2009) with 6:2 and 8:2 FTOHs in majority. The major source of environmental FTOHs has been postulated to come from the residual unreacted FTOH present in commercial products (Ellis et al., 2003). "
ABSTRACT: Fluorotelomer alcohols [FTOHs, F(CF(2) )(n) CH(2) CH(2) OH, n = 4, 6, and 8] are emerging environmental contaminants. Biotransformation of FTOHs by mixed bacterial cultures has been reported; however, little is known about the microorganisms responsible for the biotransformation. Here we reported biotransformation of FTOHs by two well-studied Pseudomonas strains: Pseudomonas butanovora (butane oxidizer) and Pseudomonas oleovorans (octane oxidizer). Both strains could defluorinate 4:2, 6:2, and 8:2 FTOHs, with a higher degree of defluorination for 4:2 FTOH. According to the identified metabolites, P. oleovorans transformed FTOHs via two pathways I and II. The pathway I led to the production of x:2 ketone [dominant metabolite, F(CF(2) )(x) C(O)CH(3) ; x = n - 1, n = 6 or 8], x:2 sFTOH [F(CF(2) )(x) CH(OH)CH(3) ], and perfluorinated carboxylic acids (PFCAs, perfluorohexanoic, or perfluorooctanoic acid). The pathway II resulted in the formation of x:3 polyfluorinated acid [F(CF(2) )(x) CH(2) CH(2) COOH] and relatively minor shorter-chain PFCAs (perfluorobutyric or perfluorohexanoic acid). Conversely, P. butanovora transformed FTOHs by using the pathway I, leading to the production of x:2 ketone, x:2 sFTOH, and PFCAs. This is the first study to show that individual bacterium can bio-transform FTOHs via different or preferred transformation pathways to remove multiple CF(2) groups from FTOHs to form shorter-chain PFCAs. Biotechnol. Bioeng. © 2012 Wiley Periodicals, Inc.Biotechnology and Bioengineering 12/2012; 109(12). DOI:10.1002/bit.24561 · 4.16 Impact Factor
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- "Per-and polyfluoroalkyl compounds (PFCs) are persistent against the typical environmental degradation processes and have been found ubiquitously in water (Saito et al., 2003; Schultz et al., 2004; So et al., 2004; Yamashita et al., 2005; Ahrens et al., 2010a,b; Busch et al., 2010), air (Martin et al., 2002; Stock et al., 2004, 2007; Jahnke et al., 2007), sediment (Bao et al., 2009, 2010; Gómez et al., 2011; Yang et al., 2011), sludge (Higgins et al., 2005), precipitation (Liu et al., 2009), wildlife (Giesy and Kannan, 2001; Li et al., 2008a,b) and humans (Yeung et al., 2006, 2008; Jin et al., 2007) around the globe. Because of their chemical characteristics , including extraordinary stability, hydrophobicity, oleophobicity and surfactant characteristics, many PFCs have been broadly applied to industrial and domestic production in the past half-century (OECD, 2002; Prevedouros et al., 2006). "
ABSTRACT: The spatial distribution of per- and polyfluoroalkyl compounds (PFCs) were investigated in coastal waters collected onboard research vessel Snow Dragon from the East to South China Sea in 2010. All samples were prepared by solid-phase extraction and analyzed using high performance liquid chromatography/negative electrospray ionization-tandem mass spectrometry (HPLC/(-)ESI-MS/MS). Concentrations of 9 PFCs, including C(4) and C(8) (PFBS, PFOS) perfluoroalkyl sulfonate (PFSAs), C(5)-C(9) and C(13) (PFPA, PFHxA, PFHpA, PFOA, PFNA, PFTriDA) perfluoroalkyl carboxylates (PFCAs), and N-ethyl perfluorooctane sulfonamide (EtFOSA) were quantified. The ΣPFC concentrations ranged from 133 pg/L to 3320 pg/L, with PFOA (37.5-1541 pg/L), PFBS (23.0-941 pg/L) and PFHpA (0-422 pg/L) as dominant compounds. Concentrations of PFCs were greater in coastal waters along Shanghai, Ningbo, Taizhou, Xiamen and along coastal cities of the Guangdong province compared to less populated areas along the east Chinese coast. Additionally, the comparison with other seawater PFC measurements showed lower levels in this study.Environmental Pollution 02/2012; 161:162-9. DOI:10.1016/j.envpol.2011.09.045 · 3.90 Impact Factor
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- "Perfluorinated compounds (PFCs) are a class of anthropogenic chemicals that are now known to be globally distributed in environmental and biological media, with recent studies documenting their presence in surface water (Skutlarek et al., 2006; Nakayama et al., 2007; Konwick et al., 2008), air (Martin et al., 2002; Stock et al., 2004, 2007), rainwater and snow (Kim and Kannan, 2007; Liu et al., 2009), wastewater effluent (Schultz et al., 2006; Loganathan et al., 2007) and wildlife (Giesy et al., 2001; Butt et al., 2010). "
ABSTRACT: A growing number of studies now indicate that perfluorinated compounds (PFCs) are globally distributed in the environment. Their widespread distribution and presence in remote locations has led to questions about the importance of atmospheric and oceanic transport. Describing their distribution in surface soils is also an essential but neglected element in developing a comprehensive understanding of their occurrence in the environment. Soils are the critical link between global atmospheric and hydrologic processes where both local and distant contaminants can accumulate and be released into aquatic and terrestrial communities. Because PFC concentrations in soils will influence ground and surface water, wildlife, and crops, methods to accurately measure PFCs in soil are clearly needed. To help answer this need, we developed a method for the analysis of nine perfluorinated carboxylic acids and four perfluorinated sulfonic acids in soil. Samples from six nations (n=10 per nation) were analyzed by LC-MS/MS to demonstrate the method performance parameters and to make preliminary observations about the occurrence of the PFCs in soils in different parts of the world. The resulting method shows acceptable performance characteristics for the target compounds in most soils while documenting the widespread occurrence of PFCs in surface soils.Chemosphere 11/2011; 86(3):252-7. DOI:10.1016/j.chemosphere.2011.09.036 · 3.50 Impact Factor