Adrián de la Torre

Concentrations and sources of Dechlorane Plus in sewage sludge.

Sewage sludge from 31 urban Spanish wastewater treatment plants (WWTP) was analyzed for the emerging halogenated flame retardant Dechlorane Plus (DP). Concentrations of the two major isomers in the technical mixture, syn and anti, ranged between 0.903-19.2 and 1.55-75.1ngg(-1) dry weight, respectively. Overall, concentrations of DP were lower than those of polybrominated diphenyl ethers (PBDEs) (9.10-995ngg(-1) dry weight) and this is likely related to the higher usage of brominated flame retardants. The average ratio of the syn isomer to total DP (f(syn)) was 0.28±0.05, which is similar to that of the commercial mixture. Comparing different wastewater treatment methods, we found lower concentrations in those using biological nitrogen and phosphorous elimination, suggesting that DP is susceptible to microbial degradation and that anti-DP is more so, given the enrichment of syn-DP in the sewage sludge. Principal components analysis revealed significant positive correlation (r=0.619, p<0.05) between total DP concentrations with the contribution of industrial input to waste streams. This implies release of DP is related to industrial activity, likely stemming from the use of the technical product during manufacture of consumer goods. However, use and disposal of products containing DP could not be dismissed. According to our knowledge, this is the first report on DP in WWTP sludge.

Identification and trace level determination of brominated flame retardants by liquid chromatography/quadrupole linear ion trap mass spectrometry

We describe the development of instrumental methodology for the simultaneous determination of hexabromocyclododecane (HBCD) diastereoisomers and tetrabromobisphenol A (TBBPA) and its derivatives by liquid chromatography/quadrupole linear ion trap mass spectrometry (LC-QqLIT-MS). Two different experiments were developed, optimized and compared. The first is based on a selected reaction monitoring (SRM) method in which the two most abundant transitions were selected for each analyte, as well as for the internal standards. In the second, the ion trap was used for the storage and subsequent fragmentation of precursor ions, obtaining an enhanced product ion (EPI) experiment. Both methods were validated by measuring quality parameters such as linearity, sensitivity, reproducibility and repeatability. Limits of detection (LODs) were in the range of 0.1-1.8 pg and 0.01-0.5 pg for SRM and EPI experiments, respectively, being lower than those published for the LC/QqQ-MS methods. Thus, LC-QqLIT-MS, used for quantification and confirmation, proved to be a powerful and very sensitive analytical tool.

Uptake of perfluoroalkyl substances and halogenated flame retardants by crop plants grown in biosolids-amended soils

Abstract The bioaccumulation behavior of perfluoroalkyl substances (PFASs) and halogenated flame retardants (HFRs) was examined in three horticultural crops and earthworms. Two species, spinach (Spinacia oleracea) and tomato (Solanum lycopersicum L.), were grown in field soil amended with a single application of biosolids (at agronomic rate for nitrogen), to represent the scenario using commercial biosolids as fertilizer, and the third crop, corn (Zea mays) was grown in spiked soil (˜50 mg PFOS/kg soil, ˜5 mg Deca‐BDE/kg soil and a mixture of both, ˜50 mg PFOS and ˜5 mg Deca‐BDE/kg soil) to represent a worst‐case scenario. To examine the bioaccumulation in soil invertebrates, earthworms (Eisenia andrei) were exposed to the spiked soil where corn had been grown. PFASs and HFRs were detected in the three crops and earthworms. To evaluate the distribution of the compounds in the different plant tissues, transfer factors (TFs) were calculated, with TF values higher for PFASs than PBDEs in all crop plants: from 2 to 9‐fold in spinach, 2 to 34‐fold in tomato and 11 to 309‐fold in corn. Bioaccumulation factor (BAF) values in earthworms were also higher for PFASs (4.06±2.23) than PBDEs (0.02±0.02). Graphical abstract Symbol. No caption available. HighlightsPFASs and HFRs were detected in plants cultivated in biosolids‐amended soils.Bioaccumulation of PFASs and HFRs in three hortical crops and earthworms was found.Transfer factors (TFs) were higher for PFASs than PBDEs in all crop plants.Long‐chain PFASs remained in roots and short‐chain ones translocated to aerial tissues.Bioaccumulation factor (BAF) values in earthworms were higher for PFASs than PBDEs.

Environmental risk assessment of perfluoroalkyl substances and halogenated flame retardants released from biosolids-amended soils

Biosolid application is considered a sustainable management tool as it positively contributes to recycle nutrients and to improve soil properties and fertility. Nevertheless, this waste management technique involves an important input source of emerging organic pollutants in soil. To evaluate the environmental potential risk related to perfluoroalkyl substances (PFASs) and halogenated flame retardants (HFRs) due to the biosolid application to soil, a quantitative ecotoxicological risk assessment was conducted. The analyte concentrations were employed to perform an estimation of the exposure levels to contaminants in the receiving media, defining predicted environmental concentrations (PECs) for terrestrial and aquatic compartments (PECsoil, PECwater, PECsed) and for secondary poisoning via the terrestrial and aquatic food chain (PECoral, predator (T), PECoral, predator (Aq)). The risk characterization ratios (RCRs) were calculated based in the comparison of the PEC values obtained with concentrations with no effect (PNECs) on terrestrial and aquatic ecosystems. Based on the chosen scenarios and experimental conditions, no environmental risk of PFASs and HFRs released from biosolid amended soils to different environmental compartments was detected (RCRsoil, RCRoral, worm, RCRwater, RCRsed and RCRoral, fish were below 1 in all cases). Besides, the potential health risk of PFASs and HFRs to local people who live in the scenario studied and are fed on horticultural crops grown in biosolid amended soil was also below 1, indicating that the risk is not considered significant to human health in the conditions studied. This approach provides a first insight of the risks relative to biosolid amendments to further research based on fieldwork risk assessment.