Jordi Parera

Serum levels of polychlorinated dibenzodioxins and dibenzofurans and PCBs in the general population living near an urban waste treatment plant in Biscay, Basque Country.

Levels of PCDD/Fs and dioxin-like PCBs were measured in 16 pooled samples of serum from a total of 322 adults in the general population, to coincide with the start-up of a new municipal solid urban waste treatment plant in Biscay, Basque Country (Spain). Two hundred and eighty-three individual serum samples were also obtained, in which the most common PCBs (28, 52, 101, 118, 138, 153 and 180) were quantified. The samples were taken from four geographical zones: two from the metropolitan area of Bilbao, located less than 2 km from the plant and with high traffic density (Zones E1 and E2), a third located 5 km from the plant in an urban area of Bilbao, also with high traffic density (Zone C1) and the fourth located 20 km from the plant, in a municipality with minimal industrial activity and low traffic density (Zone C2), the latter two being out of the path of the prevailing winds. The median levels of dioxins+furans were similar by zone: E1=24.3, E2=27.3, C1=21.3, C2=18.8 pg g(-1) lipid (p=0.362); by sex: 20.2 vs. 22.6 pg g(-1) lipid in men and women (p=0.328); and by age: 20.8 vs. 21.3 pg g(-1) lipid in subjects aged 20-44 and 45-69 (p=0.505). No detectable levels of PCBs 52 and 101 were found. Significant differences by zone were found only for PCB 180 (p=0.041), with higher values in Zone C2, the zone with the lowest presumed contamination levels. Dioxin-like PCBs (p<0.001) and the most common PCBs (138, 153, 180) (p<0.001) were both statistically associated with age, higher values being found in the 45-69 age group.

Polychlorinated dibenzo-p-dioxins, dibenzofurans, biphenyls, paraffins and polybrominated diphenyl ethers in marine fish species from Ebro River Delta (Spain)

The results of a surveillance programme on the determination of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and short chain chlorinated paraffins (SCCPs) in marine fish and shellfish species which are fished, commercialised and consumed in the Ebro River Delta area (NE, Spain) are presented. The study included the analysis of five marine fish species (sardine, gilthead sea bream, conger, eel and flounder) and three shellfish species (murex, carpet shell and mussel) collected in 2012 in five fishing harbours near to this area. WHO-TEQ concentrations for PCDD/Fs and dioxin like PCBs (dl-PCBs) ranged from 0.03 to 0.31 pg WHO-TEQ2005PCDD/Fg(-1)wetweight (ww) and from 0.02 to 3.15 pg WHO-TEQ2005PCBg(-1)ww, respectively. All levels were below the maximum concentrations established by the EU Regulation. The PCBs and PCDD/Fs accumulation pattern found in the samples analysed showed a distribution typically reported for marine samples. For marker PCBs and PBDEs, concentration levels ranging from 929 to 57494 pg g(-1)ww and from 36.2 to 827 pg g(-1)ww were obtained, respectively, meanwhile for SCCPs levels were between 3.1 and 141 ng g(-1)ww. Finally, the trends in the levels of PCDD/F and dl-PCBs found from 2006 to 2012 in fish and shellfish species were studied. A slight decrease of PCDD/F and dl-PCB concentrations was found since 2006.

Persistent Organic Pollutants in gull eggs of two species (Larus michahellis and Larus audouinii) from the Ebro delta Natural Park.

The aim of this study was to determine the impact of priority and emerging Persistent Organic Pollutants (POPs) in gull eggs from two species, the scavenger Larus michahellis and the protected species, Larus audouinii. These two species share habitat in the Natural Park of the Ebro delta (Catalonia, Spain). Compounds studied are included or under consideration in the Stockholm Convention and comprise polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), organochlorinated compounds (OCs), perfluorinated compounds (PFCs) and short chain chlorinated paraffins (SCCPs). Four methods based in selective extraction and gas or liquid chromatography coupled to mass spectrometry were used and quality parameters are provided. OC pesticides and marker PCBs were the most abundant chemical families detected in eggs from the two species, followed by PFCs, PBDEs (especially BDE 209) and SCCPs. Dioxin-like PCBs and PCDD/Fs were also detected in all samples. The overall widespread presence of POPs is discussed in terms of feeding habits, bird ecology and anthropogenic pressures in the protected Ebro delta breeding area.

Suitability of selective pressurized liquid extraction combined with gas chromatography-ion-trap tandem mass spectrometry for the analysis of polybrominated diphenyl ethers

A one-step extraction and clean-up method using pressurized liquid extraction (PLE) (selective PLE) combined with gas chromatography-ion-trap tandem mass spectrometry (GC-ITMS-MS) was evaluated for the analysis of polybrominated diphenyl ethers (from tri- to hepta-PBDEs) at low concentrations in fish and shellfish samples. To this end, the performance of an on-line PLE extraction/clean-up method and of a classical Soxhlet extraction and clean-up method using a multi-layer modified silica column were compared. The two sample treatment methods provided similar results, although an important reduction in the sample treatment time (40 min per sample) was achieved using the selective PLE method. In addition, the suitability of the PLE combined with GC-ITMS-MS method was evaluated by comparing the results obtained in the analysis of fish samples with those obtained by gas chromatography-high resolution mass spectrometry (GC-HRMS). Good agreement between both techniques was obtained with differences between the mean values of less than 16%. The selective PLE method coupled to GC-ITMS-MS produced accurate results for PBDE determination with low limits of detection (1.0-16.8 pg g(-1) wet weight) and quantification (3.1-51 pg g(-1) wet weight) as well as good precision (RSD<16%). This method has been applied to the analysis of PBDEs in fish and shellfish samples collected at fish markets in Catalonia (NE Spain).

Evolution of PCDD/Fs and dioxin-like PCBs in the general adult population living close to a MSW incinerator.

It is well known that municipal solid waste incinerators (MSWI) produce dioxins and furans. The aim of this study was to assess the serum levels of compounds with dioxin-like activity such as polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like PCBs after the commissioning of a MSWI plant. In 2006 and 2008 serum samples were obtained from 322 and 326 volunteers, respectively, from the general population, some living in the vicinity of the plant and others, as a control group, living further away from the MSWI plant and out of the path of prevailing winds. Samples for sets of 20 individuals, grouped by age and sex, were pooled, obtaining 16 pooled samples per year. No significant differences were observed in PCDD/Fs as a function of area of residence or proximity to the plant over the time of the study, with levels of WHO-TEQ/g lipid nearby and far from the MSWI being 26.9 and 20.0pg, respectively, in 2006 and 20.8 and 26.4pg, respectively, in 2008. There was a significant decrease in the concentration of non-ortho PCBs in the nearby areas, whilst there was a significant increase in the concentration of mono-ortho PCBs, both in the nearby areas and in those further away from the MSWI. Age was significantly associated with PCDD/Fs and dioxin-like PCBs, but sex showed no significant association. Overall, this study found that there was no increase in the levels of compounds with dioxin-like activity in a population living close to an MSWI, in agreement with the literature reviewed, for plants of recent construction using state-of-the-art technology.

Levels of polychlorinated dibenzo-p-dioxins, dibenzofurans and dioxin-like polychlorinated biphenyls in placentas from the Spanish INMA birth cohort study

Because fetuses are considered significantly more sensitive to various environment toxicants, there is a need for continuous biomonitoring of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls PCBs (DL-PCBs) to assess their impact on this susceptible population. The aim of this study was to assess the concentration of PCDD/Fs and DL-PCBs in placenta samples from women participating in the Spanish Environment and Childhood (INMA) birth cohort study and to evaluate whether maternal and child characteristics predict placenta concentrations of these pollutants. The presence of PCDD/Fs and DL-PCBs was investigated in 50 placenta samples selected at random in the recruitment period 2000-2008. Multivariable regression models were constructed. Mothers had a mean age at delivery of 30.7 years (18.0-38.0 years), pre-pregnancy BMI of 23.3 kg/m² (18.0-40.2 kg/m²), and 31% were smokers. Median total concentrations of PCDD/Fs and DL-PCBs were 6.9 pg WHO-TEQ/g lipid and 2.1 pg WHO-TEQ/g lipid, respectively. In comparison to the few previous studies in placenta, total TEQ levels were among the lowest recorded in comparable general populations. The congener distribution pattern and the frequencies and concentrations of PCDD/F and DL-PCB congeners were similar to previous reports in placenta. PCDD/F and DL-PCB exposure was related to the age of the mother and the year of the delivery. Although placental concentrations cannot be considered wholly appropriate predictors for evaluating fetal exposure to these contaminants, they can provide a good indication of both maternal and infant prenatal and postnatal exposure and can be used as a proxy for fetal exposure.

Biological monitoring of PCDD/Fs and PCBs in the City of Mataró. A population-based cohort study (1995-2012).

There is great concern about the exposure to PCDD/Fs in areas near solid waste incineration (SWI) plants as, in the past, thermal waste treatment was a major source of PCDD/Fs, affecting negatively the environment and the population living nearby the area of influence. The aim of the present study was to monitor PCDD/Fs and PCBs levels in blood samples in general population living nearby a modern SWI. Up to 7 different campaigns were performed between 1995 and 2012. Overall, 104 exposed subjects (living <1000 m from the incinerator plant) and 97 non-exposed subjects (living >3000 m from the incinerator plant) were randomly selected from the municipal census of the City of Mataró in 1995. In addition, workers of the SWI plant were included in the study. Moreover, in 1999, 100 non-exposed subjects living in the nearby City of Arenys de Mar were added to the project. Overall, this study represents the longest consecutive human biomonitoring study of dioxins, furans and PCBs ever conducted in Spain. Concentrations of PCDD/Fs and PCBs were determined according to age, sex and distance to the SWI exposure in whole blood sample pools. No relevant differences in PCDD/Fs and PCBs levels were observed between SWI exposure groups. It could be noted that since 1999 all groups experienced a slight decrease in the levels of PCDD/Fs and marker PCBs. Moreover, concentrations of PCDD/Fs and marker PCBs were higher in women than in men, and in older age group in comparison to the younger ones.

Occurrence and bioaccumulation study of PCDD and PCDF from mineral feed additives

Extraction of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) was evaluated in sepiolite matrices. Soxhlet extraction using different extracting strategies and acid treatment were tested. Acid treatment or Soxhlet extraction using a mixture of toluene:ethanol as solvent allowed to reach the minimum requirements for recovery rates. However, Soxhlet extraction using a mixture cyclohexane:toluene as extracting solvent did not allow to comply with these minimum requirements. Significant differences were obtained in TEQ units when acid treatment was applied in comparison to Soxhlet extraction. This fact can be explained because the use of drastic acid conditions allows removing strongly adsorbed analytes which can be uniquely extracted after a total destruction of the crystalline. On the contrary, Soxhlet extraction was not able to destroy the structure of sepiolite and as a consequence the PCDDs/Fs remain adsorbed in the internal structure of the mineral. A bioaccumulation study was also conducted to evaluate the transference of PCDDs/Fs from the sepiolite into the animal when fed with feed containing sepiolite. Four groups of chickens were exposed through diet to a control feed, feed with 3% w/w sepiolite, spiked feed contaminated with PCDDs/Fs and feed containing contaminated kaolinitic clay. Livers of animals were analyzed throughout the exposure period. Results of this trial showed that the performance of broilers was not affected by the presence of dioxins at levels tested, and chickens did not show any abnormal behaviour. Dioxins intentionally added to the diet were significantly absorbed and accumulated in liver, whereas the PCDDs/Fs from sepiolite were not available for chickens since livers from broilers fed 3% sepiolite presented similar WHO-TEQ values than those from broilers fed control diet.

Polychlorinated dibenzo-p-dioxins, dibenzofurans and dioxin-like PCBs in commercialized food products from Colombia

Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (dl-PCBs) are commonly known as dioxins and are the most toxic members of persistent organic pollutants (POPs) because present a variety of health effects especially as promoting agent of growing and transformation of cancer cells. They are bio-accumulate in humans primarily via the diet, specifically by ingestion of foods that have high lipid content which are generally associated with foods of animal origin such as oils and fats and with fishery and dairy products. In Colombia the Ministry of Health and Social Protection which is the entity responsible for surveillance food conditions, has established maximum levels for dioxins and dl-PCBs in oils from animal and vegetable origins. Oils of vegetable and animal origin represent an appreciable intake in the country thus the presence of dioxins and dl-PCBs in these materials is a matter of concern because they can bioaccumulate in fat. In this contribution the levels of PCDD/Fs and dl-PCBs in olive, soybean, fish oil, butter and shrimp consumed in Colombia were determined using HRGC-HRMS and were compared with the maximum levels permitted in oil samples according to both the Colombian and European regulations. WHO-TEQ concentrations for PCDD/Fs and dioxin like PCBs ranged from 0.24 to 1.710pgWHO-TEQ PCDD/Fg(-1) of fat and from 0.050 to 3.000pgWHO-TEQ PCBg(-1) of fat, respectively. As expected, fish oils and shrimp present the highest WHO-TEQ PCDD/Fs and dl-PCBs values followed by butter and soybean oil sample, while the olive oil shows the lowest levels. In general, the vegetable oils show levels below the limits established by both the Colombian and European regulations. The levels from soybean oil found in this study were slightly higher than the threshold established both by the Commission Regulation European Union (EU) and the Colombian legislation, while fish oils showed concentrations above the European regulations. Furthermore, shrimp exhibited values below the maximum concentration levels established by the EU and Colombian regulation.

Dioxins and dl-PCBs in gull eggs from Spanish Natural Parks (2010-2013).

The aim of this study was to evaluate the presence and distribution of polychlorinated dibenzo-p-dioxins, dibenzofurans (PCDD/Fs) and biphenyls (PCBs), concretely those so-called as dioxin-like PCBs, in yellow-legged gull eggs (Larus michahellis) collected from five Natural Parks (some of them National Parks) in Spain during the period 2010-2013. PCDD/Fs and dl-PCBs were detected in all the samples. Due to the proximity to important urban and industrial areas higher concentrations were determined in colonies located in the Northern Mediterranean coast than those found in the Southern Mediterranean or Atlantic colonies where a softer anthropogenic impact occurs. Mean ∑PCDD/F concentrations ranged from 49 to 223pg/g lipid weight (lw) and ∑dl-PCB concentrations varied from 146 to 911ng/g lw. In the Natural Park of the Ebro Delta (Northern Mediterranean coast) two gull species share habitat: yellow-legged and Audouin gull (Larus audouinii). Eggs from both species were collected and PCDD/F and dl-PCB levels compared. The species that feeds exclusively on pelagic fish (L. audouinii) had significantly higher PCDD/F and dl-PCB levels than the scavenger L. michahellis, pointing out the diet-dependent differences in the accumulation of persistent organic pollutants between similar cohabitant breeding species. Finally, mean TEQ values were in general below those considered as critical for toxicological effects in birds.