Dietary uptake of polybrominated diphenyl ethers (PBDEs), occurrence and profiles, in aquacultured turbots (Psetta maxima) from Galicia, Spain.

Polybromodiphenyl ethers (PBDEs) are one of the many toxic chemicals present in the environment and in the food we eat every day, being fish one of the main sources of persistent organic pollutants in our diet; like other lipid-related contaminants, they are of concern since they can bioaccumulate and biomagnify through the trophic chain. We published a study focused on the dietary uptake of dioxins and furans (PCDD/Fs) and dioxin-like polychlorobiphenyls (dl-PCBs) in a set of samples of Spanish farmed turbot (Blanco et al., 2007). In the present paper, we extend the study to PBDEs to provide more information about the uptake and transfer from feed to fish of halogenated contaminants. PBDEs in the feeds (2.35-4.76 ng g(-1)) were reflected in turbot fillets (0.54-2.05 ng g(-1)): predominant congeners were tetra-BDE 47, penta-BDEs 99 and 100. It is remarkable that tetra-BDE 49, accounting for only 2% in the feed, contributed to 15% of total PBDEs in turbot fillets. Dietary net accumulation values, 30-45%, showed that tri-, tetra-, penta- and hexa-BDEs were as efficiently transferred into turbot as dl-PCBs and tetra- and penta-chlorinated PCDD/Fs. Lipid-normalized biomagnification factors relating concentration in fish and in feed, BMFs>1 were obtained, except for BDE 209. BDE 49 accumulation, 90%, was possibly contributed by metabolism of higher brominated BDEs. Implication in aquaculture management is a need for uncontaminated fish feed to offer safe products.

Single-run determination of polybrominated diphenyl ethers (PBDEs) di- to deca-brominated in fish meal, fish oil and fish feed by isotope dilution: application of automated sample purification and gas chromatography/ion trap tandem mass spectrometry (GC/ITMS).

The present paper describes the application of automated cleanup and fractionation procedures of the Power Prep system (Fluid Management Systems) for the determination of polybrominated diphenyl ethers (PBDEs) in feeding stuffs and fish meal and oil. Gas chromatography (GC) separation followed by ion trap tandem mass spectrometry detection in EI mode (ITMS) allowed the analysis of di- to deca-BDEs in the samples matrices used in fish aquaculture. The method developed enabled the determination of 26 native PBDE congeners and 11 (13)C(12)-labelled congeners, including deca-BDE 209, in a single-run analysis, using isotope dilution. The automated cleanup, consisting of a succession of multilayer silica and basic alumina columns previously applied by Wyrzykowska et al. (2009) [28] in combustion flue gas, was successfully applied in our complex matrices. The method allowed an increase in productivity, i.e. lower time was required to process samples, and simultaneous purification of several samples was achieved at a time, reducing analyst dedication and human error input. Average recoveries of 43-96% were obtained. GC/ITMS can overcome the complexity originating from the sample matrix, eliminating matrix effects by tandem MS, to enable the detection of congeners penta- to nona-BDEs where interferent masses were present. The provisional detection limits, estimated in the samples, were 5-30 pg for di-, tri-, tetra-, and penta-BDEs, 20-65 pg for hexa-, hepta-, octa- and nona-BDEs, and 105 pg for deca-BDE. Reduction of deca-BDE 209 blank values is of concern to ongoing research. Good accuracy was obtained by application of the whole procedure, representing an efficient, low-cost and fast alternative for routine analyses.

Mercury, cadmium and lead levels in samples of the main traded fish and shellfish species in Galicia, Spain.

The presence of mercury, cadmium and lead has been studied in raw and processed fish and shellfish of the main traded species in Galicia (Spain) from at least 40 commercial outlets between January 2002 and October 2003. The results show that, according to European legislation, the products on the market are generally "safe", although the high levels of mercury in swordfish and shark are notable, with 22% of samples (n = 37) over the limit. We also indicate the relatively important contribution to mercury ingestion of widely consumed species, such as tuna, with 25% of samples (n = 378) over 0.25 mg kg⁻¹. Cadmium was over the limit (1.0 mg kg⁻¹) in 15% of the tested cephalopods (n = 79) and 29% of Chlamys sp. bivalves (n = 17).

Dietary uptake of dioxins (PCDD/PCDFs) and dioxin-like PCBs in Spanish aquacultured turbot (Psetta maxima).

The human population is exposed to dioxins (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs) mainly through diet; bioaccumulation and biomagnification in aquatic environment results in fishery products and by-products being an important vector to humans. The determination of PCDD/Fs and dl-PCBs in fillets of young turbots (Psetta maxima) (0-2 years) from aquaculture plant (Galicia, Spain) (N = 21) and in feeding stuffs were carried out, and dietary accumulation values and lipid-normalized biomagnification factors (BMF) relating concentration in fish and in feed were calculated. Levels found in feeding stuffs (0.5 pg TEQ-PCDD/F/g and 1.6 pg TEQ-dl-PCB/g), and turbots (0.13-0.27 pg TEQ-PCDD/F/g fresh weight and 0.35-1.2 pg TEQ-dl-PCB/g fresh weight) were below maximum permitted levels set by EC. Levels of toxic compounds in feeding stuff are reflected in fish fillets; predominant isomers are 2,3,7,8-TCDF, OCDD, 1,2,3,7,8-PeCDF, 2,3,4,7,8-PeCDF and 1,2,3,4,6,7,8-HpCDD, and PCBs 118, 105, 156 and 167. Relevant compounds accounting for total toxicity are the same congeners in feeding stuff and turbots: 2,3,4,7,8- PeCDF; 2,3,7,8-TCDF; 2,3,7,8-TCDD and 1,2,3,7,8-PeCDD, and PCB 126. Higher accumulation efficiency values were obtained for dl-PCBs (30-46%); tetra- and penta-chloro substituted PCDD/Fs showed the highest values (27-34%) of the PCDD/F group. Biomagnification was shown for these compounds (BMF around 1.5).