M.J. González

Study on PCBs, PCDD/Fs, organochlorine pesticides, heavy metals and arsenic content in freshwater fish species from the River Turia (Spain)

In this study samples of common trout, European eel and barbel have been analysed for the levels of heavy metals such as lead (Pb), cadmium (Cd), zinc (Zn), copper (Cu), and the metalloid arsenic (As). Polychlorinated biphenyls (PCBs), including three non-ortho substituted PCBs, 2,3,7,8-substituted polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and DDT and its two main metabolites were also analysed in some selected samples, in order to evaluate the extent of contamination of the River Turia basin. All samples presented detectable levels of the elements analysed, presenting zinc the highest concentrations. European eel was the species found to highly accumulate these contaminants. Regarding organochlorinated compounds, seven samples exhibited detectable levels of the most toxic PCDD/Fs congener, the 2,3,7,8-TCDD. Non-ortho PCBs were not detected or not quantified in almost all samples and the sum of the individual PCB congeners determined were low compared to other aquatic ecosystems with similar fish species.

Occurrence of organochlorine insecticides, PCBs and PCB congeners in waters and sediments of the Ebro River (Spain)

Organochlorine insecticides and poychlorinated biphenyls (PCBs) were measured in water and sediment samples taken from thirteen sites along the Ebro River (Spain), the most agricultural and industrial basin in the North of the Iberian Peninsula. Concentrations of 10 insecticides, PCBs and 13 PCB congeners were determined: grouping all chemicals by structural affinity, these can be arranged in descending order as follow: PCBs > total DDT > total cyclodiene insecticides > total HCH. Higher levels of organochlorine pollutants were detected in sediments from the middle and lower parts of the stream where are located the main important inputs in Ebro River.

Accumulation of heavy metals and As in wetland birds in the area around Doñana National Park affected by the Aznalcollar toxic spill

The impact of the spill from the mine in Aznalcollar (Seville, Spain) on waterfowl in the Doñana National Park is assessed. The concentrations of Cu, Pb, Cd, Zn nd As in the liver and eggs of 16 species of waterfowl found dead in the Park between April and November 1998 were determined. The highest levels were found for Zn, followed by Cu, Pb, Cd and As. The main parameters related to the accumulation of these elements in the waterfowl studied were species and trophic level. The other variables studied--distance from the spill, days of exposure, sex, size, and age--are important, although this depends on the element studied. Zn and Cu from the spill have entered the food chain of the aquatic birds studied, but Cd, Pb and As have not. There is currently no evidence to suggest that the trace element concentrations measured have reached toxic levels.

Dietary intakes of polychlorinated dibenzo-p-dioxins, dibenzofurans and dioxin-like polychlorinated biphenyls in Spain

Congener-specific analyses of seventeen 2,3,7,8-substituted PCDD/Fs, three non-ortho and 8 mono-ortho dioxin-like polychlorinated biphenyls (PCBs) were performed on 258 Spanish foodstuff samples, mainly of animal origin, for 2000–03. Daily dietary intakes of PCDD/Fs and PCBs, expressed as toxic equivalents (WHO-TEQs), were estimated by combining food consumption data from the Spanish National Institute Statistics survey and concentration levels measured in individual samples, using upper bound determination values (not detectable = limit of detection). The calculated dietary intake of PCDD/Fs for a person weighing 70 kg was 1.35 ± 0.11 pg WHO-TEQs kg−1 bw day−1, and 3.22 ± 0.75 pg WHO-TEQs kg−1 bw day−1 if dioxin-like PCBs (non- and mono-ortho PCBs) were included, showing the importance of their inclusion in monitoring studies. Both values were within the range of tolerable daily intake (TDI) proposed by the WHO (1–4 pg WHO-TEQs kg−1 bw day−1). The current levels are lower than earlier intakes estimates conducted in Spain. Meat and meat products accounted for more than 35% of the intake, followed by milk and milk products (29%), vegetables oils (19%), fish and sea food (11%) and eggs (4%). Dioxin-like PCBs are an important component in the total WHO-TEQs in foodstuffs. This is particularly true for the fish food group, where the total WHO-TEQs is dominated by dioxin-like PCBs (up to 80% of WHO-TEQs in some cases).

Trace elements in blood collected from birds feeding in the area around Donana National Park affected by the toxic spill from the Aznalcollar mine

A long-term monitoring plan was established to study if bird populations around Doñana National Park were affected by the toxic spill from the Aznalcóllar mine. The concentrations of Zn, Pb, As, Cu, Sb, Co, Tl and Cd in the blood of 11 bird species feeding in the area were determined. The parameters which most affect the accumulation of trace elements in the birds studied are, firstly, species and secondly, trophic position, sex, days of exposure and weight. In some individuals, Zn and Cu occurred at higher levels than the reference values for contaminated areas. Concentrations of Pb and Cd in a considerable number of individuals were higher than those found in birds from uncontaminated areas. The present data, together with the lack of data on blood metal concentration prior to the spill, do not offer any conclusive evidence of the influence of the spill on avian blood metal concentrations.

Levels of PCDDs and PCDFs in farm cow's milk located near potential contaminant sources in Asturias (Spain). Comparison with levels found in control, rural farms and commercial pasteurized cow's milks

Cows milk samples from 12 dairy farms in Spain and 23 samples of pasteurised cows milk were analysed for PCDD/F. Farms located in rural areas without specific dioxin sources (background levels) ranged from 1.3 to 2.47 pg TEQ/g fat basis. These values were slightly lower than those found in milk from the vicinity of potential dioxin emission sources (waste incinerator, chemical and metallurgical industry) and similar to milk near paper industry. The waste incinerator seems to be the emission source with the highest influence on the cows milk gathered in its vicinity. Thus, milk near the waste incinerator exhibited the highest PCDD/F levels, the highest PCDF/PCDD ratio and its congener PCDD pattern showed the highest difference respect to its control point. The PCDD/F average concentrations found in pasteurised commercial milk were lower than those found in raw milk and were comparable to those found in retail milk from other countries.

Comparison of gas chromatography-based approaches after fast miniaturised sample preparation for the monitoring of selected pesticide classes in fruits

The feasibility of a miniaturised generic sample preparation method based on matrix solid-phase dispersion for the determination of three relevant classes of pesticides (organophosphorus pesticides, triazines and pyrethroids) in selected fruits, i.e. orange, apple, pear and grape, have been demonstrated. Satisfactory results were obtained with gas chromatography coupled to mass spectrometry with recoveries of 78-113% in orange, 62-102% in grape, 71-116% in apple and 91-110% in pear, and reproducibilities in general below 20%. The feasibility of simultaneous separation of the three families of pesticides by comprehensive two-dimensional gas chromatography with micro-electro-capture detector was also evaluated. Columns with different polarity and selectivity, including ZB-5, HT-8 and DB-17, were assayed as first dimension and combined with columns of increasing polarity in the second dimension, i.e. HT-8, BPX-50 and Supelcowax-10. The best results for real-life samples after treatment by the proposed miniaturised method were achieved with ZB-5 x BPX-50 column combination. The low limits of detection achieved with this technique (in general, below 0.56 microg/kg) proved its suitability for accurate monitoring of the pesticides classes included in the study at the maximum residue levels set in the European Union.

Levels of chlorinated insecticides, total PCBs and PCB congeners in Spanish Gull eggs

Eggs from Herring Gulls, Audouin Gulls and Gull Billed Terns were collected at three different locations in Spain during the breeding season of 1988. Organochlorine pesticides, total polychlorinated biphenyls (PCBs) and seven selected individual chlorobiphenyl congeners were determined in each of the thirty infertile eggs.The levels of DDE and total PCBs in eggs from the Delta Ebro River are greater than those gathered at Chafarinas Island and Cuenca. Among the species investigated, the Gull Billed Tern eggs showed the lowest level followed by the Herring Gull and the Audouin Gull eggs.The levels of the seven congeners of PCBs showed that 138 was the most prominent, followed by, in decreasing order, 153, 180, 170, 101, 151, and 194. Congener 138 constituted 10.5% ± 2.7 (S.D) of the total PCBs concentration, the 153 8.7% ± 4.2, the 180 7.5% ± 1.9, the 170 3.2% ±1.0, the 101 1.9% ± 3.06, the 151 1.1% ± 1.5 and the 194 0.9% ± 0.5.Polychlorinated biphenyl (PCB) residues (48 congeners) from gull eggs gathered at Ebro Delta and Chafarinas Islands were analyzed with SIMCA (Soft Independent Modeling of Class Analogy), a principal components analysis technique. A series of technical Aroclors® were also analyzed to provide a reference data set for pattern recognition. Environmental PCB residue profiles differed according to the samples origin. This analysis discriminated between the two regions sampled.

Separation of chiral polychlorinated biphenyls by micellar electrokinetic chromatography using β- and γ-cyclodextrin mixtures in the separation buffer

Chiral polychlorinated biphenyls (PCBs) 45, 84, 88, 91, 95, 132, 136, 139, 149, 171, 183 and 196 were separated each in its two enantiomers by cyclodextrin-modified micellar electrokinetic chromatography (CD-MEKC). Mixtures of β- and γ-cyclodextrins were used as chiral modifiers in a 2-(N-cyclohexylamino)ethanesulphonic acid (CHES) buffer containing urea and sodium dodecyl sulphate (SDS) micelles. Separations of multicomponent mixtures of PCBs into their enantiomers were also performed. A mixture of PCBs 45, 88, 91, 95, 136, 139, 149 and 196 was separated into all sixteen enantiomers in an analysis time of approx. 35 min.

Polychlorinated naphthalenes in sediments from the Venice and Orbetello Lagoons, Italy

The purpose of this study was to evaluate the contamination caused by polychlorinated naphthalenes in two polluted Mediterranean lagoons. Surface sediment samples from Venice and Orbetello lagoons were analysed using HRGC-HRMS. The levels of the sum of mono- to octa-CN ranged from 0.03 to 1.51 ng/g. Differences in PCN levels were observed as a function of the sampling site, with levels at the industrial sites exceeding those at the control sites. Although the PCN patterns and profiles resembled one another in different sediment samples, they differed considerably when compared with those in the technical PCN formulation Halowax 1014.