Temporal trends of perfluorinated surfactants in Swedish peregrine falcon eggs (Falco peregrinus), 1974-2007.

Perfluorinated alkyl substances (PFAS) are today known to be globally distributed environmental contaminants. In the present study, concentrations of PFAS were analyzed in Swedish peregrine falcon eggs (Falco peregrinus), collected between 1974 and 2007. Analytes included in the study were perfluorinated carboxylates (PFCAs; carbon chain lengths C6-C15), perfluorinated sulfonates (PFSAs; C4, C6, C8, and C10), and perfluorooctane sulfonamide (PFOSA). The predominant PFAS was perfluorooctane sulfonate, PFOS (83 ng/g wet weight (w wt) mean concentration in samples from 2006), followed by perfluorotridecanoate, PFTriA (7.2 ng/g w wt) and perfluoroundecanoate, PFUnA (4.2 ng/g w wt). PFCA concentrations increased exponentially over the studied time. In contrast, concentrations of PFOS and perfluorohexane sulfonate (PFHxS) increased initially but leveled off after the mid 1980s. This is different from previously observed temporal trends in marine organisms. The present study is the first to establish temporal trends for PFAS in terrestrial biota. The results indicate potential differences between marine and terrestrial biota regarding sources of PFAS exposure and response to emission changes. The toxicological implications of PFAS exposure for the falcons are not known, but according to recent findings impaired hatching success and sublethal toxicological effects from PFOS exposure in the Swedish peregrine falcon cannot be ruled out.

Fish consumption as a source of human exposure to perfluorinated alkyl substances in Sweden - analysis of edible fish from Lake Vättern and the Baltic Sea.

Perfluorinated alkyl substances (PFAS) were analyzed in muscle tissue from edible fish species caught in the second largest freshwater lake in Sweden, Lake Vättern (LV), and in the brackish water Baltic Sea (BS). Perfluorooctane sulfonate (PFOS) was the predominant PFAS found. PFOS concentrations were higher in LV (medians 2.9-12 ng g(-1) fresh weight) than in BS fish (medians 1.0-2.5 ng g(-1) fresh weight). Moreover, LV fish was more contaminated with several other PFAS than BS fish. This may be due to anthropogenic discharges from urban areas around LV. The PFAS pattern differed between LV and BS fish, indicating different sources of contamination for the two study areas. Human exposure to PFOS via fish intake was calculated for three study groups, based on consumption data from literature. The groups consisted of individuals that reported moderate or high consumption of BS fish or high consumption of LV fish, respectively. The results showed that PFOS intake strongly depended on individual fish consumption as well as the fish catchment area. Median PFOS intakes were estimated to 0.15 and 0.62 ng kg(-1) body weight (bw) d(-1) for the consumers of moderate and high amounts of BS fish, respectively. For the group with high consumption of LV fish a median PFOS intake of 2.7 ng kg(-1)bw d(-1) was calculated. Fish consumption varied considerably within the consumer groups, with maximum PFOS intakes of 4.5 (BS fish) or 9.6 ng kg(-1)bw d(-1) (LV fish). Comparison of our results with literature data on PFOS intake from food suggests that fish from contaminated areas may be a significant source of dietary PFOS exposure.

Tissue distribution of perfluorinated surfactants in common guillemot (Uria aalge) from the Baltic Sea.

Perfluorinated alkyl surfactants (PFAS) were investigated in tissues and organs of the common guillemot (Uria aalge) from the Baltic Sea. Concentrations of 11 perfluorinated carboxylates, four perfluorinated sulfonates, and perfluorooctane sulfonamide were determined in egg, liver, kidney, and muscle of adult guillemot, as well as in liver from chicks, all sampled in 1989. Additionally, whole herring homogenates from 2005 were analyzed, herring comprising a large part of guillemot's diet. Quantifiable concentrations of PFAS were found in all samples. Perfluorooctane sulfonate (PFOS) was predominant, followed by perfluorotridecanoate (PFTriDA) and perfluoroundecanoate (PFUnDA). The median concentration of PFOS was highest in eggs (325 ng/g wet weight (w wt)) followed by chick liver (309 ng/g w wt), kidney (127 ng/g w wt), adult liver (121 ng/g w wt), and muscle (14 ng/g w wt). Comparatively low levels of PFOS were found in herring, leaving a blurred picture of uptake routes. PFAS concentrations in livers of male and female guillemots did not differ significantly. Some PFAS showed higher concentrations in eggs than in female livers. The ratio of levels in egg/female liver, indicating mother-to-egg transfer capacity, increased with increasing PFAS chain length. PFOS showed a higher tendency for transfer than carboxylates of carbon chain lengths C9-C13.

Riverine discharge of perfluorinated carboxylates from the European continent.

The discharge of C6-C9 perfluorinated carboxylates (PFCAs) from major European rivers was studied and employed to assess European emissions of these compounds. Water samples were collected close to the mouths of 14 major rivers including the Rhine, Danube, Elbe, Oder, Seine, Loire, and Po. PFCA concentrations were determined using LC-MS/MS and used together with the mean annual water flow to estimate the riverine discharge of the PFCAs. The highest concentration measured was 200 ng/L for perfluorooctanoate (PFOA) in the Po River. The Po accounted for two-thirds of the total PFOA discharge of all the rivers studied, suggesting a major industrial source of PFOA in the Po watershed. All other nonremote rivers showed PFOA concentrations in the lower ng/L range, which indicates that widely distributed sources are also significant contributors to PFOA emissions in Europe. The total discharge of PFOA from the European rivers was estimated to be 14 tonnes/year, which is in reasonable agreement with reported emissions estimates. However, the total riverine discharge of perfluorohexanoate (PFHxA) of 2.8 tonnes/year estimated in this study was three times greater than the reported global emissions estimate, suggesting that there are significant, as yet unidentified sources of this compound.

Temporal trends of PFOS and PFOA in guillemot eggs from the Baltic Sea, 1968--2003.

Perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) have recently been identified as ubiquitous environmental contaminants. Although they have been produced for 50 years, little is known about when they first appeared in the environment and how their concentrations have changed over time, particularly in response to the phase-out of PFOS, which began in 2000. In this study temporal trends in the concentrations of PFOS and PFOA in the Baltic Sea marine environmentwere measured using archived guillemot eggs. Samples collected from Stora Karlsö (Sweden) between 1968 and 2003 were received from an environmental specimen bank and concentrations of PFOS and PFOA were analyzed using HPLC coupled to ESI-MS/MS. PFOA was not detected in any of the samples (LOD 3 ng/g), but there was an almost 30-fold increase in PFOS concentrations in the guillemot eggs during the time period, from 25 ng/g in 1968 to 614 ng/g in 2003 (wet weight). Regression analysis indicated a significant trend, increasing on average between 7 and 11% per year. A sharp peak in PFOS concentrations was observed in 1997 followed by decreasing levels up to 2002, but this cannot be linked to the PFOS phase-out, which occurred at the end of this period.