Contamination of soils by metals and organic micropollutants: case study of the Parisian conurbation.

Soils are playing a central role in the transfer and accumulation of anthropogenic pollutants in urbanized regions. Hence, this study aimed at examining the contamination levels of selected soils collected within and around the Paris conurbation (France). This also evaluated factors controlling contamination. Twenty-three trace and major elements as well as 82 organic micropollutants including polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), phthalates (PAEs), polybrominated diphenyl ethers (PBDEs), alkylphenols (APs), and perfluoroalkylated substances (PFASs) were analyzed. Results reinforced the concern raised by the occurrence and levels of metals such as Zn, Pb, Cu, and Hg, identified as metallic markers of anthropogenic activities, but also pointed out the ubiquitous contamination of soils by organic micropollutants in the 0.2-55,000-µg/kg dw range. For well-documented compounds like PAHs, PCBs, and to a lesser extent PBDEs, contents were in the range of background levels worldwide. The pollutant stock in tested soil was compared to the annual atmospheric input. For PAHs; Pb; and to a lesser extent Zn, Cu, Cd, Hg, Sb, PAEs, and APs, a significant stock was observed, far more important than the recent annual atmospheric fluxes. This resulted from both (i) the persistence of a fraction of pollutants in surface soils and (ii) the cumulative atmospheric inputs over several decades. Regarding PBDEs and PFASs, stronger atmospheric input contributions were observed, thereby highlighting their recent dispersal into the environment.

Occurrence of antibiotics in rural catchments.

The transfer of 23 antibiotics from domestic and hospital sources was investigated in two elementary river watersheds receiving wastewater treatment plant (WWTP) discharges, in relation with the hydrological cycle and seasonal conditions. Antibiotic concentrations in the effluent of a WWTP treating wastewaters from both hospital and domestic sources (18-12 850 ng L-1) were far higher than those from domestic sources exclusively (3-550 ng L-1). In rivers, upstream of the WWTP discharges, fluoroquinolones only were found at low concentrations (≤10 ng L-1). Their presence might be explained by transfer from contaminated agricultural fields located on the river banks. Immediately downstream of the WWTP discharge, antibiotic occurrence increased strongly with mean concentrations up to 1210 ng L-1 for ofloxacin and 100% detection frequencies for vancomycin, sulfamethoxazole, trimethoprim and three fluoroquinolones. Dilution processes during high-flow periods led to concentrations 14 times lower than during low-flow periods. Downstream of the discharge, the antibiotic dissipation rate from the water column was higher for fluoroquinolones, in relation with their high sorption upon suspended matter and sediment. Only five antibiotics (vancomycin and four fluoroquinolones ciprofloxacin, norfloxacin, ofloxacin and enoxacin) were partly distributed (11%-36%) in the particulate phase. Downstream of the discharge, antibiotic contents in sediment ranged from 1700 to 3500 ng g-1 dry weight, fluoroquinolones accounting for 97% of the total.

Fate of antibiotics from hospital and domestic sources in a sewage network.

Investigation of domestic and hospital effluents in a sewage system of an elementary watershed showed that antibiotics belonging to eight classes were present with concentrations ranging from

Cat serum contamination by phthalates, PCBs, and PBDEs versus food and indoor air.

A wide variety of endocrine disrupting compounds (EDCs) with semi-volatile properties are emitted to indoor air and, thus, humans might get exposed to these compounds. Pet cats spend the major part of their lifetime at home and might integrate indoor contamination so that they could mirror the human exposure. Three classes of EDCs, polybromodiphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), and phthalates (PAEs), were simultaneously considered and quantified in the serum of cats (Felis silvestris catus) living in the Paris area (France). The main compound concentrations by decreasing importance order were as follows: for PAEs, di-n-butyl phthalate (79,900 ng L(-1)) next di-iso-butyl phthalate (53,200 ng L(-1)), di-iso-nonyl phthalate (43,800 ng L(-1)), and di-ethylhexyl phthalate (32,830 ng L(-1)); for PCBs, CB153 (1378 ng L(-1)) next CB52 (509 ng L(-1)), CB101 (355 ng L(-1)), CB110 (264 ng L(-1)), and CB118 (165 ng L(-1)); and for PBDEs, BDE 153/154 (35 ng L(-1)) next BDE47 (10.7 ng L(-1)). Total serum concentrations as mean ± standard deviation were 107 ± 98 µg L(-1) for ∑9PAEs, 2799 ± 944 ng L(-1) for ∑19PCBs, and 56 ± 21 ng L(-1) for ∑9BDEs. The three chemical groups were found in cat food: 0.088 ng g(-1) for ∑9BDEs, 1.7 ng g(-1) for ∑19PCBs, and 2292 ng g(-1) for ∑9PAEs and in indoor air: 0.063 ng m(-3) for ∑9BDEs, 1.5 ng m(-3) for ∑19PCBs, and 848 ng m(-3) for ∑9PAEs. Contaminant intake by food ingestion was approximately 100-fold higher than that by indoor air inhalation.

Endocrine disrupting compounds in gaseous and particulate outdoor air phases according to environmental factors.

This study investigated, for the first time in France, the spatial and temporal patterns of 55 endocrine disrupting chemicals (EDCs) in ambient air at three sites (urban, suburban and forest) under two climatic periods (warm/cold) for 2 successive years. All EDCs, except tetrabromobisphenol A (TBBPA), were encountered with various frequencies of up to 100%. Phthalate diesters (PAEs) were the most abundant chemicals with total concentrations as the sum of compounds, ranging from 10 to 100 ng m(-3) of total air, followed by alkylphenols (APs) and polycyclic aromatic hydrocarbons (PAHs), which were both approximately 1 ng m(-3). Polychlorinated biphenyl (PCBs) and bisphenol A (BPA) concentrations were notably lower (approximately 0.1 ng m(-3)). Air concentrations, depending on the considered compounds, were from 1.2 to 2 times higher in the urban than the suburban area and from 2 to 5 times higher in the urban than the forest site. PAH emissions were higher in the cold period, due to combustion processes. This finding is contrary to the other EDCs that are more abundant in the summer and governed by volatilisation. Most of the EDCs were largely distributed in the gaseous phase (>80% in the summer). The octanol/air partition coefficient (KOA) and vapour pressure (Vp) were relevant parameters for predicting EDC partitioning and direct relationships (p < 0.001) were observed i) between log K particle/gas partitioning (log Kp) and log KOA and ii) between EDC ratios in the gaseous phase and log vapour pressure (log Vp).

Fate of phthalates and BPA in agricultural and non-agricultural soils of the Paris area (France).

This study (i) investigated the concentration levels of nine phthalates and bisphenol A (BPA) in sludge samples originating from a French wastewater treatment plant (WWTP), (ii) studied the distribution of target compounds according to soil depth and calculated their half-lives, and (iii) compared the contamination level of the agricultural soil with those of soils with other land uses. The sludge contamination levels varied from a few hundred nanograms per gram dry weight (dw) for diethyl phthalate (DEP), di-iso-butyl phthalate (DiBP), di-n-butyl phthalate (DnBP), and butyl-benzyl phthalate (BBP) to a few micrograms per gram dw for diethylhexyl phthalate (DEHP), di-iso-nonyl phthalate (DiNP), and di-iso-decyl phthalate (DiDP). After sludge application, an 8-fold increase for DEHP level and a 3-fold increase for BPA level occurred in the surface horizon of the soil. The mean distribution of phthalates according to the depth showed a positive gradient for the low molecular weight compounds and inversely, a negative gradient for the highest ones. The half-lives in the 0-20-cm soil horizon were 64 days for DEHP and 36 days for BPA. A predictive environmental concentration (PEC) of 0.3 µg g(-1) dw was estimated for DEHP, while the experimental value was 0.16 µg g(-1) dw, suggesting degradation processes in soil and/or formation of non-extractable residues. Comparisons of contamination levels for soils from different origins (urban, rural, agricultural, and forest) showed that the urban soil remained the most contaminated one, prior to the agricultural soil after treatment.

BPA and phthalate fate in a sewage network and an elementary river of France. Influence of hydroclimatic conditions.

Our purpose was to characterize the fate of bisphenol A (BPA) and phthalate contamination simultaneously in a sewage network and a watercourse, in relation with hydrological and climatic conditions. An elementary catchment of the Seine basin, receiving effluents from a wastewater treatment plant (WWTP), was chosen because of its basic hydrological features. BPA and DEHP concentrations in the WWTP inputs were 4 and 33 µg L(-1) whereas in the outputs, they were only 0.4 and 2 µg L(-1), respectively. Contaminant ratios in the suspended sediment phase of the WWTP inputs ranged from 0.5% to 88%, related to their molecular properties. BPA and phthalates were effectively removed in the WWTP (>90% for both compounds), by degradation and decantation. Upstream of the discharge, river concentrations ranged from 0.002 to 0.175 µg L(-1) for BPA and from 0.16 to 0.90 µg L(-1) for DEHP. Downstream from the WWTP outputs, concentrations ranged from 0.11 to 0.79 µg L(-1) for BPA and from 0.31 µg L(-1) to 1.7 µg L(-1) for DEHP: the WWTP discharge led to contaminant increases of 3.8 and 2 times, respectively. Far downstream, concentrations were lower ranging from 0.11 to 0.19 µg L(-1) for BPA and from 0.36 µg L(-1) to 1.1 µg L(-1) for DEHP. BPA and phthalates displayed opposite seasonal variations with a decrease for the first one and an increase for the second one during summer. BPA contamination in the Charmoise river derived mainly from the WWTP, while phthalate contamination was attributed to both WWTP discharges and diffuse sources such as atmospheric bulk deposition.

Determination of phthalates and their by-products in tissues of roach (Rutilus rutilus) from the Orge river (France).

Seven phthalate by-products were investigated for the first time, in target tissues of roach from a contaminated river of the Ile-de-France district. All parent phthalates were bioaccumulated in liver and muscle and liver contents were correlated with river concentrations (p < 0.01). All metabolites were found in liver, plasma and bile. The mono-iso-butyl phthalate (MiBP; 1.6 µg g(-1) dw of liver), followed by mono-n-butyl phthalate (MnBP; 1.5 µg g(-1) dw of liver) were the most abundant ones. Among the three metabolites of di-ethylhexyl phthalate (DEHP), mono (2-ethylhexyl) phthalate (MEHP) predominated in bile (15.5 ng ml(-1)) and liver (0.237 µg g(-1) dw), whereas in plasma, it was mono (2-ethyl-5-hydroxyhexyl) phthalate - MEHHP (214 ng ml(-1)). In liver, MEHP/DEHP ratios ranged from 0.04 to 0.2. Among the oxidized metabolites, only mono (2-ethyl-5-oxohexyl) phthalate (MEOHP) was correlated (p < 0.05) with parent DEHP and appeared to be a more reliable marker of DEHP impact than the monoester.

Polychlorinated biphenyls, polybrominated diphenyl ethers, and phthalates in roach from the Seine River basin (France): impact of densely urbanized areas.

Endocrine disruptors (EDs) from three chemical classes-polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and phthalates-were investigated in the Seine River and one tributary, the Orge River, upstream and downstream of urban areas. The impact of urban areas was characterized by a concentration increase of all compounds in the Seine River and for phthalates and PBDEs in the Orge River. In the Seine River, from upstream (Marnay) to downstream (Triel) of urban areas, water concentration increases were greater for diethylhexyl phthalate (DEHP) (6 times, p < 0.05) and ∑tri-hexa BDE (5 times [p < 0.05]) than for ∑7PCBi (2.6 times). Simultaneously, sediments displayed a strong accumulation of contaminants downstream and compared with upstream values, their concentrations increased greatly: 202-fold for DEHP, 69-fold for BDE209, 25-fold for ∑tri-hexa-BDE, and 11-fold for ∑7PCBi. Variations of fish ED concentrations gave an indication of their habitat contamination increase observed downstream of densely urbanized areas of the Seine River, especially for PBDEs (∑tri-hexa-PBDEs = 14-fold increase ≤15.7 ± 6.9 ng g(-1) dry weight [dw; p < 0.001]) and for PCBs (∑7PCBi eightfold increase ≤211 ± 55 ng g(-1) dw [p < 0.01]). PCA results highlighted relationships between the different ED classes. A correlation (p < 0.05) was observed between PCB and PBDE fish concentrations, suggesting common sources and similar absorption mechanisms. For PCBs, which were poorly biodegraded, the bioaccumulation factor was strongly correlated (p < 0.001) to molecular hydrophobicity, whereas for PBDEs a negative correlation (p < 0.05) was observed related active debromination processes. This multichemical study investigates for the first time the occurrence of a wide range of EDs in roach, which was chosen as a sentinel species for this survey of surface water contamination.

Occurrence of polybrominated diphenyl ethers, polychlorinated biphenyls, and phthalates in freshwater fish from the Orge river (Ile-de France).

Polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), and phthalates were investigated from July 2009 to April 2010 in three fish species from the Orge river, which flows in a densely populated area of Ile-de-France. In two Cyprinidae (roach and chub) and one Percidae (perch), muscle contents in increasing order ranged as follows: 12-18 ng g(-1) dw for PBDEs (Σtri-hepta), 120-170 ng g(-1) dw for PCBs (Σ7), and 2,250-5,125 ng g(-1) dw for phthalates (Σ7). No variation was observed between contaminant contents and lipid levels. No biomagnification was found according to the trophic level for PBDEs and PCBs, whereas for phthalates the highest contents were found in perch. Seasonal variations were observed with the lowest PBDE and PCB contents occurring in July after spawning in roach and perch (p < 0.001). PBDE content followed a decreasing trend-gonad > liver > muscle-whatever the period. For PCBs, gonad and liver contents remained greater than that of muscle (p < 0.05). Our results indicate a preferential accumulation of halogenated compounds in gonad and liver outside the reproduction period. Bioaccumulation factors for PCBs in muscle were significantly correlated to their chlorination degree in perch (p < 0.01) and roach (p < 0.01). In roach, that correlation slope was by decreasing importance order as follows: gonad > liver > muscle. The biota-sediment accumulation factors varied from 0.1 to 29.2, from 1.6 to 4.8, and from 1 to 123.5 for PBDEs, PCBs, and phthalates, respectively. These results contribute to document the use of freshwater fish as bioindicators of river quality.

Phthalate removal throughout wastewater treatment plant: case study of Marne Aval station (France).

The fate of six phthalates: dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DnBP), butyl benzyl phthalate (BBP), bis (2-ethylhexyl) phthalate (DEHP) and di-n-octyl phthalate (DnOP) was investigated throughout wastewater treatment processes in the wastewater treatment plant (WWTP) of Marne Aval (France). That plant treats wastewater from a highly populated area and was used as a pilot station for development of nitrification processes. In wastewater, at each step of treatment, DEHP was always the major compound (9 to 44 microg L(-1)), followed by DEP (1.6 to 25 microg L(-1)). Other phthalates averaged 1 microg L(-1) and DnOP remained close to the detection limit in nearly all cases. In sludge, the prevailing compound was also DEHP (72 microg g(-1)) which is consistent with its tendency to get sorbed upon suspended matter (SM). DnOP came in third, in relation with its resistance to biodegradation. For the studied period, the removal efficiency of DEHP from wastewater was about 78%. That removal seemed to proceed rather from particle settling than from biodegradation. A highly significant correlation (p<0.001) was found between DEHP and SM concentrations throughout treatment processes. The other compounds: DMP, DEP, DnBP and BBP, displayed satisfactory efficiencies ranging from 68 to over 96% for the lighter ones obviously more easily degraded. Under rainy periods, the plant discharge impact upon Marne River quality in terms of phthalate fluxes, appeared to be minor as compared to the amount brought by the storm overflows in the same area. Downstream of the WWTP discharge, DEHP concentration remained under the European norm for surface water (NQE: 1.3 microg L(-1)). Our study documents the behaviour of phthalate esters throughout a WWTP which treatment device is used by 55% of the WWTP in the river Seine basin.