Chemosphere xxx (2014) xxx–xxx
Contents lists available at ScienceDirect
Chemosphere journal homepage: www.elsevier.com/locate/chemosphere
Perfluoroalkyl acids in various edible Baltic, freshwater, and farmed fish in Finland Jani Koponen a,⇑, Riikka Airaksinen a, Anja Hallikainen b, Pekka J. Vuorinen c, Jaakko Mannio d, Hannu Kiviranta a a
National Institute for Health and Welfare, Department of Environmental Health, Kuopio, Finland Finnish Food Safety Authority Evira, Helsinki, Finland Finnish Game and Fisheries Research Institute, Helsinki, Finland d Finnish Environment Institute, Helsinki, Finland b c
h i g h l i g h t s Domestic Baltic and freshwater fish are a source of PFAAs in the Finnish diet. Total PFAA concentration in the Baltic and freshwater fishes varied from 0.31 to 46 ng g
1
fresh weight.
Farmed fish in Finland is not a significant dietary source of PFAA for humans. PFAA levels in a single fish species are not representative of the PFAA contamination in a given area.
a r t i c l e
i n f o
Article history: Received 29 March 2014 Received in revised form 14 August 2014 Accepted 26 August 2014 Available online xxxx Handling Editor: I. Cousins Keywords: Perfluoroalkyl acid Baltic fish PFOS Dietary source Finland
a b s t r a c t In this study, the concentration of perfluoroalkyl acids (PFAAs) in various edible Finnish Baltic Sea, freshwater, and farmed fish species were analysed. PFAAs were present in all the Baltic and freshwater species, but were not observed in any farmed fish. The most abundant compound in each species was perfluorooctane sulfonate (PFOS), comprising 41–100% of the total concentration. The total PFAA concentration varied considerably from 0.31 to 46 ng g 1 fresh weight. A notable variation in the PFAA concentrations implies that a single fish species alone is not suitable for monitoring PFAA contamination in a certain area. Our results confirm that wild domestic fish is one of the PFAA source in the Finnish diet. Ó 2014 Elsevier Ltd. All rights reserved.
1. Introduction Perfluoroalkyl acids (PFAAs), including perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS), are a subgroup of per- and polyfluorinated alkyl substances (PFAS). These substances have been widely used in many industrial and commercial
Abbreviations: fw, fresh weight; LC–ESI–MS/MS, liquid chromatography electrospray tandem mass spectrometry; LOQ, limits of quantification; PFAA, perfluoroalkyl acid; PFAS, per- and polyfluorinated alkyl substances; PFOS, perfluorooctane sulfonic acid. ⇑ Corresponding author. Address: P.O. Box 95, FI-70701 Kuopio, Finland. Tel.: +358 29 524 6350; fax: +358 29 524 6499. E-mail address: jani.koponen@thl.fi (J. Koponen).
applications (Buck et al., 2011). Since the carbon–fluorine bond is extremely strong and stable some of these compounds are chemically and biologically inert. However, these properties are highly related to the molecular weight and number of C–F bonds of the compound (Buck et al., 2011). Although the PFAAs are persistent, a bioaccumulative potential of the compounds is highly dependent on a chain length of the fluorinated carbons, Perfluorinated carboxylates with seven fluorinated carbons or less are not bioaccumulative according to regulatory criteria (Conder et al., 2008). PFAAs are ubiquitous in the environment and present in both environmental and human matrices (Fromme et al., 2009). The use of PFOS has been limited in EU-legislation almost a decade ago (directive 2006/122/EC) and its use in water resistant consumer products will be reconsidered again in 2015.
http://dx.doi.org/10.1016/j.chemosphere.2014.08.077 0045-6535/Ó 2014 Elsevier Ltd. All rights reserved.
Please cite this article in press as: Koponen, J., et al. Perfluoroalkyl acids in various edible Baltic, freshwater, and farmed fish in Finland. Chemosphere (2014), http://dx.doi.org/10.1016/j.chemosphere.2014.08.077
2
J. Koponen et al. / Chemosphere xxx (2014) xxx–xxx
Compounds in many classes of environmental pollutants have been associated with adverse health effects. PFAS may increase total and LDL cholesterol and the risk of breast cancer (Nelson et al., 2009; Steenland et al., 2009; Frisbee et al., 2010; Bonefeld-Jorgensen et al., 2011). Dietary intake is believed to be the major exposure route for PFAAs in the general adult population (Fromme et al., 2009; Haug et al., 2011; Vestergren et al., 2012). The Baltic Sea is highly susceptible to pollution because it is a closed sea area with little water exchange with the North Sea, and because of its large catchment area with a population of about 85 million people and a high number of pollutant sources. The environmental pollutant levels in Baltic fish are often higher than in larger water bodies such as the Atlantic and Pacific oceans (Burreau et al., 2006). In Baltic herring and salmon (Isosaari et al., 2006; Szlinder-Richert et al., 2009; Airaksinen et al., 2014), the levels of pollutants, such as dioxins and PCBs, occasionally exceed the legal maximum levels for fish set by EU (1258/2011). Fish and seafood have been found to be one of the major sources of human dietary exposure to PFAAs in the Nordic diet (Haug et al., 2010b; Vestergren et al., 2012). Yearly consumption of a domestic fish in Finland has been estimated to be 3.8 kg per person, including Baltic herring (0.3 kg), pike–perch (0.3 kg), perch (0.5 kg), whitefish (0.2 kg), vendace (0.6 kg) and farmed rainbow trout (1.0 kg) (FGFRI, 2012). The main objective of this study was to collect data about PFAA concentrations in fish commonly consumed in Finland for future dietary intake and human exposure assessments, and to investigate possible correlations between PFAA concentrations and selected physiological parameters in fish. In the future, this data can be utilized as a reference data for the measures taken in the follow up and monitoring of contaminated Baltic Sea fish.
fishing areas across the Finnish coast of the Baltic Sea (areas nearby the cities of Oulu, Pori, Turku, Hanko, and Kotka), Helsinki Vanhankaupunginlahti bay, a large freshwater Lake Päijänne, and four fish farming facilities (Fig. 1). Most of the individual samples were pooled. The pooled samples consisted of 2–10 individuals. Fish age was determined in scale or appropriate bony structure. The samples were frozen until preparation. From the large fish, a medallion was cut from around the dorsal fin and for small fish, the head was removed. Intestine and skin were removed, and meat and subcutaneous fat were homogenized to form a pooled sample according to EU directive 1883/2006. The homogenized fish samples were freeze-dried and stored frozen until PFAA analysis.
2. Materials and methods
2.3. PFAA analysis
2.1. Sampling and preparation
For quantitation prior to an extraction procedure a 2.5 ng of mass labelled internal standards in 50 lL of methanol were added into 0.3 g of freeze-dried fish samples. The samples were extracted twice with 2 mL of 20 mM ammonium acetate in methanol. After mixing for 10 min at 2500 rpm with Vibramax 110 (Schwabach, Germany), the samples were centrifuged with Eppendorf 5810 (Hamburg, Germany) at 2500 g for 10 min. The supernatants were collected. The extracts were evaporated to dryness under a nitrogen flow and reconstituted to 300 lL of 60% aqueous methanol. Prior to instrumental analysis, the samples were filtered with 0.2 lm syringe filter (Pall Life Sciences, Ann Arbor, MI). The PFAAs were analysed using liquid chromatography negative ion electrospray tandem mass spectrometry (LC–ESI–MS/MS). Details of the
The species collected from the Baltic Sea were Baltic herring (Clupea harengus), pike–perch (Sander lucioperca), perch (Perca fluviatilis), burbot (Lota lota), whitefish (Coregonus lavaretus), salmon (Salmo salar), and vendace (Coregonus albula). In addition, perch and pike– perch were collected from Helsinki Vanhankaupunginlahti bay, and perch was collected from Lake Päijänne. Farmed fish species included in this study were whitefish and rainbow trout (Oncorhynchus mykiss) (Table 1). The selection of fish species was mainly based on the significance of fish in the Finnish diet. Altogether 296 individual fish samples were collected in 2009–2010 from five commercially and recreationally important
2.2. Chemicals and reagents Methanol (HPLC grade) and ammonium acetate were obtained from J.T. Baker (Deventer, the Netherlands), and N-methylpiperidine from Sigma–Aldrich (St. Louis, MO, USA). All the native PFAAs, i.e. perfluorohexanoic acid (PFHxA), -heptanoic acid (PFHpA), -octanoic acid (PFOA), -nonanoic acid (PFNA), -decanoic acid (PFDA), -undecanoic acid (PFUnA), -dodecanoic acid (PFDoA), -tridecanoic acid (PFTrA), -tetradecanoic acid (PFTeA), -hexanesulfonate (PFHxS), -heptanesulfonate (PFHpS), -octanesulfonate (PFOS) and -decanesulfonate (PFDS) were acquired from Wellington Laboratories Inc (Guelph, Ontario, Canada). Isotope labelled PFAAs (abb. MPFAA) were used as internal standards. MPFOA (1,2,3,4-13C4), MPFNA (1,2,3,4,5-13C5), MPFUnA (1,2,3,4,5,6,7-13C7), MPFDoA (1,2-13C2), MPFHxS (18O2) and MPFOS (1,2,3,4-13C4) were obtained from Wellington Laboratories Inc. and MPFDA (1,2,3,4,5,6,7,8,9-13C9) was from CIL (Andover, MA, USA).
Table 1 Gender, length, weight, age, and fat percentage in Baltic, freshwater, and farmed fish. Fishing area
Species
Region
Gender
Length (cm)
Weight (g)
Age (year)
Fat (%)
Baltic Sea
Baltic herring (n = 58) Pike–perch (n = 30) Perch (n = 25) Burbot (n = 49) Whitefish (n = 27) Salmon (n = 44) Vendace (n = 20)
Pori Oulu, Oulu, Oulu, Oulu, Oulu, Oulu
Male, female Male, female Male, female Male, female Male, female Male, female Female
16–22 37–45 26–28 47–58 29–51 76–94 16–17
28–76 420–830 200–290 590–1430 240–1250 4740–9320 29–36
4.2–17 3.4–7.0 5.2–8.0 3.0–5.6 2.5–6.6 1.8–2.2 1.8–2.0
2.2–13 0.93–3.1 1.8–2.9 0.71–0.89 2.7–6.7 13–20 5.1–5.4
Vanhankaupunginlahti bay
Pike–perch (n = 6) Perch (n = 7)
Helsinki Helsinki
Female Male, female
31–51 17–22
230–1110 70–130
3.0–9.0 5.0–10
n/a n/a
Lake Päijänne
Perch (n = 10)
Päijänne
Male, female
20–25
87–190
8.0–10
1.2–1.8
Farmed fish
Whitefish (n = 10) Rainbow trout (n = 10)
Northern and Southern Finland Central and Southern Finland
Male, female Female
38–39 45–50
650–670 1280–1830
n/a n/a
21–23 17–18
Turku, Kotka Pori, Turku, Hanko, Pori, Turku, Hanko, Pori, Turku, Hanko, Pori, Turku, Hanko,
Kotka Kotka Kotka Kotka
n = Number of individual fishes. n/a Not analysed.
Please cite this article in press as: Koponen, J., et al. Perfluoroalkyl acids in various edible Baltic, freshwater, and farmed fish in Finland. Chemosphere (2014), http://dx.doi.org/10.1016/j.chemosphere.2014.08.077
J. Koponen et al. / Chemosphere xxx (2014) xxx–xxx
3
Fig. 1. Map of the sampling areas. The numbered points represent regions off the cities of (1) Oulu, (2) Pori, (3) Turku, (4) Hanko, and (5) Kotka in the Finnish coast of the Baltic Sea, as well as (6) Helsinki Vanhankaupunginlahti bay and (7) Lake Päijänne. The fish farming facilities are not shown on the map.
LC–ESI–MS/MS parameters and quantitation have been presented earlier (Koponen et al., 2013). Concentrations of PFAAs are reported as ng g 1 fresh weight (fw). Limits of quantification (LOQs) for PFHxA, PFHpA, PFOA, PFNA, PFDA, PFUnA, PFDoA, PFHxS and PFOS was 0.18–0.39 ng g 1, and for PFTrA, PFTeA and PFDS 0.33–0.65 ng g 1 fw. In each sample batch, a blank sample and an in-house fish control sample, treated exactly as the real fish samples, were determined. Level of the PFAAs in the blank sample was below the LOQ, so a subtraction from the results of the real samples was not necessary. PFAA-spiked, homogenized and freeze-dried rainbow trout was used as the in-house control sample for determining an inter-batch (day to day) precision of the analysis. Coefficient of variation (CV) for the inter-batch precision for PFAAs was 3.0–23%, which was considered acceptable. Recoveries of the spiked-PFAAs were 72–138%. 2.4. Statistical analysis A correlation between the total PFAA concentration and the physiological parameters (weight, age and fat percentage) of fish was evaluated using either Pearson’s or Spearman’s correlation coefficient. Kolmogorov–Smirnov test was used to evaluate a normality of the data. Values at p < 0.05 was considered statistically significant. 3. Results and discussion Seven different PFAAs were detected in the fish samples, namely PFOS, PFOA, PFNA, PFDA, PFUnA, PFDoA, and PFTrA (Table 2). The most abundant compound in all of the samples was PFOS, comprising 41–100% of the total concentration.
3.1. PFAAs in Baltic fish Total PFAA concentration in fish of the Baltic Sea varied from 0.31 to 10 ng g 1 fw (Table 2). Overall, the concentrations were of similar magnitude than those observed in the Swedish Baltic coast (Berger et al., 2009). The highest PFAA concentrations in single sample (pooled or individual fish sample) were found in Baltic herring and pike–perch, and the lowest in burbot and whitefish, which differed from the previous report (Berger et al., 2009). The highest median concentration was found in salmon and pike–perch, and the lowest in burbot and vendace. There was substantial variation in the concentrations between individuals among the same species. PFOS was the most abundant compound found in every sample comprising 48–100% of the total concentration as has been detected in Canadian fish species (Houde et al., 2006). PFNA was present in nearly all the samples, whereas PFOA, ubiquitous in the environment (Fromme et al., 2009), was detected only in some specimens of Baltic herring. Low concentration of PFDA, PFUnA and PFTrA was also detected in some species. The short chain PFHxA, PFHpA and PFHxS, as well as long chain PFDoA, PFTeA and PFDS were not present in any of the samples. Similar homologue pattern as in the present study has also been observed in previous studies (Berger et al., 2009; van Leeuwen et al., 2009; Noorlander et al., 2011; Domingo et al., 2012). The Baltic fish in this study were collected from five different sampling areas of the northern and southern Finnish coast of the Baltic Sea (Fig. 1). The total PFAA concentration in each fish species in the sampling areas are shown in Fig. 2. Baltic herring and vendace were collected only from one sampling area and therefore not included in the Fig. 2. There were differences in total PFAA concentrations both between species and between different sampling areas among same species. The results show that the lowest PFAA
Please cite this article in press as: Koponen, J., et al. Perfluoroalkyl acids in various edible Baltic, freshwater, and farmed fish in Finland. Chemosphere (2014), http://dx.doi.org/10.1016/j.chemosphere.2014.08.077
4
J. Koponen et al. / Chemosphere xxx (2014) xxx–xxx
Table 2 Perfluoroalkyl acids (PFAAs) in Baltic, freshwater, and farmed fish. PFAA concentration (ng g
1
fresh weight)a,b
Fishing area
Species
PFOS
PFOA
PFNA
PFDA
PFUnA
PFDoA
PFTrA
Total (median)
Baltic Sea
Baltic herring (n = 58) Pike–perch (n = 30) Perch (n = 25) Burbot (n = 49) Whitefish (n = 27) Salmon (n = 44) Vendace (n = 20)
0.86–4.8 2.1–4.9 1.2–4.8 0.31–7.5 0.33–4.6 1.5–5.6 0.60–0.88
Contents lists available at ScienceDirect
Chemosphere journal homepage: www.elsevier.com/locate/chemosphere
Perfluoroalkyl acids in various edible Baltic, freshwater, and farmed fish in Finland Jani Koponen a,⇑, Riikka Airaksinen a, Anja Hallikainen b, Pekka J. Vuorinen c, Jaakko Mannio d, Hannu Kiviranta a a
National Institute for Health and Welfare, Department of Environmental Health, Kuopio, Finland Finnish Food Safety Authority Evira, Helsinki, Finland Finnish Game and Fisheries Research Institute, Helsinki, Finland d Finnish Environment Institute, Helsinki, Finland b c
h i g h l i g h t s Domestic Baltic and freshwater fish are a source of PFAAs in the Finnish diet. Total PFAA concentration in the Baltic and freshwater fishes varied from 0.31 to 46 ng g
1
fresh weight.
Farmed fish in Finland is not a significant dietary source of PFAA for humans. PFAA levels in a single fish species are not representative of the PFAA contamination in a given area.
a r t i c l e
i n f o
Article history: Received 29 March 2014 Received in revised form 14 August 2014 Accepted 26 August 2014 Available online xxxx Handling Editor: I. Cousins Keywords: Perfluoroalkyl acid Baltic fish PFOS Dietary source Finland
a b s t r a c t In this study, the concentration of perfluoroalkyl acids (PFAAs) in various edible Finnish Baltic Sea, freshwater, and farmed fish species were analysed. PFAAs were present in all the Baltic and freshwater species, but were not observed in any farmed fish. The most abundant compound in each species was perfluorooctane sulfonate (PFOS), comprising 41–100% of the total concentration. The total PFAA concentration varied considerably from 0.31 to 46 ng g 1 fresh weight. A notable variation in the PFAA concentrations implies that a single fish species alone is not suitable for monitoring PFAA contamination in a certain area. Our results confirm that wild domestic fish is one of the PFAA source in the Finnish diet. Ó 2014 Elsevier Ltd. All rights reserved.
1. Introduction Perfluoroalkyl acids (PFAAs), including perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS), are a subgroup of per- and polyfluorinated alkyl substances (PFAS). These substances have been widely used in many industrial and commercial
Abbreviations: fw, fresh weight; LC–ESI–MS/MS, liquid chromatography electrospray tandem mass spectrometry; LOQ, limits of quantification; PFAA, perfluoroalkyl acid; PFAS, per- and polyfluorinated alkyl substances; PFOS, perfluorooctane sulfonic acid. ⇑ Corresponding author. Address: P.O. Box 95, FI-70701 Kuopio, Finland. Tel.: +358 29 524 6350; fax: +358 29 524 6499. E-mail address: jani.koponen@thl.fi (J. Koponen).
applications (Buck et al., 2011). Since the carbon–fluorine bond is extremely strong and stable some of these compounds are chemically and biologically inert. However, these properties are highly related to the molecular weight and number of C–F bonds of the compound (Buck et al., 2011). Although the PFAAs are persistent, a bioaccumulative potential of the compounds is highly dependent on a chain length of the fluorinated carbons, Perfluorinated carboxylates with seven fluorinated carbons or less are not bioaccumulative according to regulatory criteria (Conder et al., 2008). PFAAs are ubiquitous in the environment and present in both environmental and human matrices (Fromme et al., 2009). The use of PFOS has been limited in EU-legislation almost a decade ago (directive 2006/122/EC) and its use in water resistant consumer products will be reconsidered again in 2015.
http://dx.doi.org/10.1016/j.chemosphere.2014.08.077 0045-6535/Ó 2014 Elsevier Ltd. All rights reserved.
Please cite this article in press as: Koponen, J., et al. Perfluoroalkyl acids in various edible Baltic, freshwater, and farmed fish in Finland. Chemosphere (2014), http://dx.doi.org/10.1016/j.chemosphere.2014.08.077
2
J. Koponen et al. / Chemosphere xxx (2014) xxx–xxx
Compounds in many classes of environmental pollutants have been associated with adverse health effects. PFAS may increase total and LDL cholesterol and the risk of breast cancer (Nelson et al., 2009; Steenland et al., 2009; Frisbee et al., 2010; Bonefeld-Jorgensen et al., 2011). Dietary intake is believed to be the major exposure route for PFAAs in the general adult population (Fromme et al., 2009; Haug et al., 2011; Vestergren et al., 2012). The Baltic Sea is highly susceptible to pollution because it is a closed sea area with little water exchange with the North Sea, and because of its large catchment area with a population of about 85 million people and a high number of pollutant sources. The environmental pollutant levels in Baltic fish are often higher than in larger water bodies such as the Atlantic and Pacific oceans (Burreau et al., 2006). In Baltic herring and salmon (Isosaari et al., 2006; Szlinder-Richert et al., 2009; Airaksinen et al., 2014), the levels of pollutants, such as dioxins and PCBs, occasionally exceed the legal maximum levels for fish set by EU (1258/2011). Fish and seafood have been found to be one of the major sources of human dietary exposure to PFAAs in the Nordic diet (Haug et al., 2010b; Vestergren et al., 2012). Yearly consumption of a domestic fish in Finland has been estimated to be 3.8 kg per person, including Baltic herring (0.3 kg), pike–perch (0.3 kg), perch (0.5 kg), whitefish (0.2 kg), vendace (0.6 kg) and farmed rainbow trout (1.0 kg) (FGFRI, 2012). The main objective of this study was to collect data about PFAA concentrations in fish commonly consumed in Finland for future dietary intake and human exposure assessments, and to investigate possible correlations between PFAA concentrations and selected physiological parameters in fish. In the future, this data can be utilized as a reference data for the measures taken in the follow up and monitoring of contaminated Baltic Sea fish.
fishing areas across the Finnish coast of the Baltic Sea (areas nearby the cities of Oulu, Pori, Turku, Hanko, and Kotka), Helsinki Vanhankaupunginlahti bay, a large freshwater Lake Päijänne, and four fish farming facilities (Fig. 1). Most of the individual samples were pooled. The pooled samples consisted of 2–10 individuals. Fish age was determined in scale or appropriate bony structure. The samples were frozen until preparation. From the large fish, a medallion was cut from around the dorsal fin and for small fish, the head was removed. Intestine and skin were removed, and meat and subcutaneous fat were homogenized to form a pooled sample according to EU directive 1883/2006. The homogenized fish samples were freeze-dried and stored frozen until PFAA analysis.
2. Materials and methods
2.3. PFAA analysis
2.1. Sampling and preparation
For quantitation prior to an extraction procedure a 2.5 ng of mass labelled internal standards in 50 lL of methanol were added into 0.3 g of freeze-dried fish samples. The samples were extracted twice with 2 mL of 20 mM ammonium acetate in methanol. After mixing for 10 min at 2500 rpm with Vibramax 110 (Schwabach, Germany), the samples were centrifuged with Eppendorf 5810 (Hamburg, Germany) at 2500 g for 10 min. The supernatants were collected. The extracts were evaporated to dryness under a nitrogen flow and reconstituted to 300 lL of 60% aqueous methanol. Prior to instrumental analysis, the samples were filtered with 0.2 lm syringe filter (Pall Life Sciences, Ann Arbor, MI). The PFAAs were analysed using liquid chromatography negative ion electrospray tandem mass spectrometry (LC–ESI–MS/MS). Details of the
The species collected from the Baltic Sea were Baltic herring (Clupea harengus), pike–perch (Sander lucioperca), perch (Perca fluviatilis), burbot (Lota lota), whitefish (Coregonus lavaretus), salmon (Salmo salar), and vendace (Coregonus albula). In addition, perch and pike– perch were collected from Helsinki Vanhankaupunginlahti bay, and perch was collected from Lake Päijänne. Farmed fish species included in this study were whitefish and rainbow trout (Oncorhynchus mykiss) (Table 1). The selection of fish species was mainly based on the significance of fish in the Finnish diet. Altogether 296 individual fish samples were collected in 2009–2010 from five commercially and recreationally important
2.2. Chemicals and reagents Methanol (HPLC grade) and ammonium acetate were obtained from J.T. Baker (Deventer, the Netherlands), and N-methylpiperidine from Sigma–Aldrich (St. Louis, MO, USA). All the native PFAAs, i.e. perfluorohexanoic acid (PFHxA), -heptanoic acid (PFHpA), -octanoic acid (PFOA), -nonanoic acid (PFNA), -decanoic acid (PFDA), -undecanoic acid (PFUnA), -dodecanoic acid (PFDoA), -tridecanoic acid (PFTrA), -tetradecanoic acid (PFTeA), -hexanesulfonate (PFHxS), -heptanesulfonate (PFHpS), -octanesulfonate (PFOS) and -decanesulfonate (PFDS) were acquired from Wellington Laboratories Inc (Guelph, Ontario, Canada). Isotope labelled PFAAs (abb. MPFAA) were used as internal standards. MPFOA (1,2,3,4-13C4), MPFNA (1,2,3,4,5-13C5), MPFUnA (1,2,3,4,5,6,7-13C7), MPFDoA (1,2-13C2), MPFHxS (18O2) and MPFOS (1,2,3,4-13C4) were obtained from Wellington Laboratories Inc. and MPFDA (1,2,3,4,5,6,7,8,9-13C9) was from CIL (Andover, MA, USA).
Table 1 Gender, length, weight, age, and fat percentage in Baltic, freshwater, and farmed fish. Fishing area
Species
Region
Gender
Length (cm)
Weight (g)
Age (year)
Fat (%)
Baltic Sea
Baltic herring (n = 58) Pike–perch (n = 30) Perch (n = 25) Burbot (n = 49) Whitefish (n = 27) Salmon (n = 44) Vendace (n = 20)
Pori Oulu, Oulu, Oulu, Oulu, Oulu, Oulu
Male, female Male, female Male, female Male, female Male, female Male, female Female
16–22 37–45 26–28 47–58 29–51 76–94 16–17
28–76 420–830 200–290 590–1430 240–1250 4740–9320 29–36
4.2–17 3.4–7.0 5.2–8.0 3.0–5.6 2.5–6.6 1.8–2.2 1.8–2.0
2.2–13 0.93–3.1 1.8–2.9 0.71–0.89 2.7–6.7 13–20 5.1–5.4
Vanhankaupunginlahti bay
Pike–perch (n = 6) Perch (n = 7)
Helsinki Helsinki
Female Male, female
31–51 17–22
230–1110 70–130
3.0–9.0 5.0–10
n/a n/a
Lake Päijänne
Perch (n = 10)
Päijänne
Male, female
20–25
87–190
8.0–10
1.2–1.8
Farmed fish
Whitefish (n = 10) Rainbow trout (n = 10)
Northern and Southern Finland Central and Southern Finland
Male, female Female
38–39 45–50
650–670 1280–1830
n/a n/a
21–23 17–18
Turku, Kotka Pori, Turku, Hanko, Pori, Turku, Hanko, Pori, Turku, Hanko, Pori, Turku, Hanko,
Kotka Kotka Kotka Kotka
n = Number of individual fishes. n/a Not analysed.
Please cite this article in press as: Koponen, J., et al. Perfluoroalkyl acids in various edible Baltic, freshwater, and farmed fish in Finland. Chemosphere (2014), http://dx.doi.org/10.1016/j.chemosphere.2014.08.077
J. Koponen et al. / Chemosphere xxx (2014) xxx–xxx
3
Fig. 1. Map of the sampling areas. The numbered points represent regions off the cities of (1) Oulu, (2) Pori, (3) Turku, (4) Hanko, and (5) Kotka in the Finnish coast of the Baltic Sea, as well as (6) Helsinki Vanhankaupunginlahti bay and (7) Lake Päijänne. The fish farming facilities are not shown on the map.
LC–ESI–MS/MS parameters and quantitation have been presented earlier (Koponen et al., 2013). Concentrations of PFAAs are reported as ng g 1 fresh weight (fw). Limits of quantification (LOQs) for PFHxA, PFHpA, PFOA, PFNA, PFDA, PFUnA, PFDoA, PFHxS and PFOS was 0.18–0.39 ng g 1, and for PFTrA, PFTeA and PFDS 0.33–0.65 ng g 1 fw. In each sample batch, a blank sample and an in-house fish control sample, treated exactly as the real fish samples, were determined. Level of the PFAAs in the blank sample was below the LOQ, so a subtraction from the results of the real samples was not necessary. PFAA-spiked, homogenized and freeze-dried rainbow trout was used as the in-house control sample for determining an inter-batch (day to day) precision of the analysis. Coefficient of variation (CV) for the inter-batch precision for PFAAs was 3.0–23%, which was considered acceptable. Recoveries of the spiked-PFAAs were 72–138%. 2.4. Statistical analysis A correlation between the total PFAA concentration and the physiological parameters (weight, age and fat percentage) of fish was evaluated using either Pearson’s or Spearman’s correlation coefficient. Kolmogorov–Smirnov test was used to evaluate a normality of the data. Values at p < 0.05 was considered statistically significant. 3. Results and discussion Seven different PFAAs were detected in the fish samples, namely PFOS, PFOA, PFNA, PFDA, PFUnA, PFDoA, and PFTrA (Table 2). The most abundant compound in all of the samples was PFOS, comprising 41–100% of the total concentration.
3.1. PFAAs in Baltic fish Total PFAA concentration in fish of the Baltic Sea varied from 0.31 to 10 ng g 1 fw (Table 2). Overall, the concentrations were of similar magnitude than those observed in the Swedish Baltic coast (Berger et al., 2009). The highest PFAA concentrations in single sample (pooled or individual fish sample) were found in Baltic herring and pike–perch, and the lowest in burbot and whitefish, which differed from the previous report (Berger et al., 2009). The highest median concentration was found in salmon and pike–perch, and the lowest in burbot and vendace. There was substantial variation in the concentrations between individuals among the same species. PFOS was the most abundant compound found in every sample comprising 48–100% of the total concentration as has been detected in Canadian fish species (Houde et al., 2006). PFNA was present in nearly all the samples, whereas PFOA, ubiquitous in the environment (Fromme et al., 2009), was detected only in some specimens of Baltic herring. Low concentration of PFDA, PFUnA and PFTrA was also detected in some species. The short chain PFHxA, PFHpA and PFHxS, as well as long chain PFDoA, PFTeA and PFDS were not present in any of the samples. Similar homologue pattern as in the present study has also been observed in previous studies (Berger et al., 2009; van Leeuwen et al., 2009; Noorlander et al., 2011; Domingo et al., 2012). The Baltic fish in this study were collected from five different sampling areas of the northern and southern Finnish coast of the Baltic Sea (Fig. 1). The total PFAA concentration in each fish species in the sampling areas are shown in Fig. 2. Baltic herring and vendace were collected only from one sampling area and therefore not included in the Fig. 2. There were differences in total PFAA concentrations both between species and between different sampling areas among same species. The results show that the lowest PFAA
Please cite this article in press as: Koponen, J., et al. Perfluoroalkyl acids in various edible Baltic, freshwater, and farmed fish in Finland. Chemosphere (2014), http://dx.doi.org/10.1016/j.chemosphere.2014.08.077
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Table 2 Perfluoroalkyl acids (PFAAs) in Baltic, freshwater, and farmed fish. PFAA concentration (ng g
1
fresh weight)a,b
Fishing area
Species
PFOS
PFOA
PFNA
PFDA
PFUnA
PFDoA
PFTrA
Total (median)
Baltic Sea
Baltic herring (n = 58) Pike–perch (n = 30) Perch (n = 25) Burbot (n = 49) Whitefish (n = 27) Salmon (n = 44) Vendace (n = 20)
0.86–4.8 2.1–4.9 1.2–4.8 0.31–7.5 0.33–4.6 1.5–5.6 0.60–0.88
