IVL Swedish Environmental Research Institute

Abstract The biomagnification of per- and polyfluoroalkyl substances (PFASs) was investigated in a tropical mangrove food web from an estuary in Bahia, Brazil. Samples of 44 organisms (21 taxa), along with biofilm, leaves, sediment and suspended particulate matter were analyzed. Sum (∑) PFAS concentrations in biota samples were dominated by perfluorooctane sulfonate (PFOS, 93% detection frequency in tissues; 0.05 to 1.97 ng g⁻¹ ww whole-body (wb)), followed by perfluorotridecanoate (PFTrDA, 57%; 0.01 to 0.28 ng g⁻¹ ww wb). PFOS precursors such as perfluorooctane sulfonamide (FOSA, 54%; 0.01 to 0.32 ng g⁻¹ ww wb) and N-ethyl perfluorooctane sulfonamide (EtFOSA; 30%; 0.01 to 0.21 ng g⁻¹ ww wb) were also detected. PFAS accumulation profiles revealed different routes of exposure among bivalve, crustacean and fish groups. Statistics for left-censored data were used in order to minimize bias on trophic magnification factors (TMFs) calculations. TMFs >1 were observed for PFOS (linear + branched isomers), EtFOSA (linear + branched isomers), and perfluorononanoate (PFNA), and in all cases, dissimilar accumulation patterns were observed among different trophic positions. The apparent biodilution of some long-chain PFCAs through the food chain (TMF < 1) may be due to exposure from multiple PFAS sources. This is the first study investigating bioaccumulation of PFASs in a tropical food web and provides new insight on the behavior of this ubiquitous class of contaminants.

Incineration is the dominant treatment for residual waste in Sweden. It is desirable to reach complete thermal oxidation of chemical substances in the incineration process to destroy toxic substances contained in waste. Otherwise, there is a risk of toxic substances being released into the environment through incineration residuals. This project has investigated to which extent Swedish waste incineration plants emit PFAS (per- and polyfluoroalkyl substances) via bottom ash, fly ash and condensate water. 

Of 38 incineration plants in Sweden, 27 (in total 31 furnaces) joined the project, answered questionnaires about operating parameters, and sampled incineration residuals. Five samples from each matrix, fly ash, bottom ash, or condensate water, were collected during a two-week period to compensate for the variation over time. 

The collected samples of bottom ash, fly ash and condensate were analysed for 27 different PFAS according to a methodology developed by IVL Swedish Environmental Research Institute, based on LC-MS / MS. Out of the 27 incineration plants in this project, five plants had no samples with PFAS-27 concentrations above the analytical limit of detection in any of the matrices. Generally, the results show low concentrations in the sampled matrices from most plants, with a few exceptions. No apparent relationships were found between the analysed concentrations of PFAS in the sampling matrices and the operational data.

Abstract Twenty per- and polyfluoroalkyl substances (PFAS) were determined in human milk from residents of three Chinese cities (Shanghai, Jiaxing, and Shaoxing), sampled between 2010 and 2016. These data were compared to a combination of new and previously reported PFAS concentrations in human milk from Stockholm, Sweden, collected in 2016. Across the three Chinese cities, perfluorooctanoate (PFOA; sum isomers), 9-chlorohexadecafluoro-3-oxanone-1-sulfonic acid (9Cl-PF3ONS; trade name F53-B), and perfluorooctane sulfonate (PFOS; sum isomers) occurred at the highest concentrations among all PFAS (up to 411, 976, and 321 pg/mL, respectively), while in Stockholm, PFOA and PFOS were dominant (up to 89 and 72 pg/mL, respectively). 3H-perfluoro-3-[(3-methoxy-propoxy) propanoic acid (ADONA) was intermittently detected but at concentrations below the method quantification limit (i.e. <10 pg/mL) in Chinese samples, and was non-detectable in Swedish milk. The extremely high concentrations of F53-B in Chinese milk suggest that human exposure assessments focused only on legacy substances may severely underestimate overall PFAS exposure in breastfeeding infants.

Abstract Twenty per- and polyfluoroalkyl substances (PFAS) were determined in human milk from residents of three Chinese cities (Shanghai, Jiaxing, and Shaoxing), sampled between 2010 and 2016.

These data were compared to a combination of new and previously reported PFAS concentrations in human milk from Stockholm, Sweden, collected in 2016.

Across the three Chinese cities, perfluorooctanoate (PFOA; sum isomers), 9-chlorohexadecafluoro-3-oxanone-1-sulfonic acid (9Cl-PF3ONS; trade name F53-B), and perfluorooctane sulfonate (PFOS; sum isomers) occurred at the highest concentrations among all PFAS (up to 411, 976, and 321 pg/mL, respectively), while in Stockholm, PFOA and PFOS were dominant (up to 89 and 72 pg/mL, respectively).

3H-perfluoro-3-[(3-methoxy-propoxy) propanoic acid (ADONA) was intermittently detected but at concentrations below the method quantification limit (i.e. <10 pg/mL) in Chinese samples, and was non-detectable in Swedish milk.

The extremely high concentrations of F53-B in Chinese milk suggest that human exposure assessments focused only on legacy substances may severely underestimate overall PFAS exposure in breastfeeding infants.

The high proportion of unidentified extractable organofluorine (EOF) observed globally in humans and the environment indicates widespread occurrence of unknown per- and polyfluoroalkyl substances (PFAS).

However, efforts to standardize or assess the reproducibility of EOF methods are currently lacking. Here we present the first EOF interlaboratory comparison in water and sludge. Three participants (four organizations) analyzed unfortified and PFAS-fortified ultrapure water, two unfortified groundwater samples, unfortified wastewater treatment plant effluent and sludge, and an unfortified groundwater extract.

Participants adopted common sample handling strategies and target lists for EOF mass balance but used in-house combustion ion-chromatography (CIC) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods.

EOF accuracy ranged from 85-101% and 76-109% for the 60 and 334 ng L-1 fluorine (F) - fortified water samples, respectively, with between-laboratory variation of 9-19%, and within-laboratory variation of 3-27%. In unfortified sludge and aqueous samples, between-laboratory variation ranged from 21-37%.

The contribution from sum concentrations of 16 individual PFAS (∑PFAS-16) to EOF ranged from 2.2-60% but extended analysis showed that other targets were prevalent, in particular ultra-short-chain perfluoroalkyl acids (e.g. trifluoroacetic acid) in aqueous samples and perfluoroalkyl acid-precursors (e.g. polyfluoroalkyl phosphate diesters) in sludge.

The EOF-CIC method demonstrated promising accuracy, robustness and reporting limits but poor extraction efficiency was observed for some targets (e.g. trifluoroacetic acid).