[en] Highlights: • OPEs were detected for the first time in NW African Mediterranean coastal aerosols. • The general predominance of non-Cl-OPEs suggests local sources in the area. • TiBP identified as potential good tracer of local sources in Bizerte area. • Up to ~9 kg y⁻¹(~1 kg y⁻¹ organic anthropogenic P) can be loaded in Bizerte lagoon. Organophosphate ester (OPE) flame retardants and plasticizers have been detected at generally high frequencies (70–98%) for the first time in the atmosphere over the NW African coastal Mediterranean. Results from sixty air samples (total suspended particles, TSP) collected between March 2015 and January 2016 in an urban coastal site (Bizerte, Tunisia) revealed ∑₉OPE concentrations of ~100–1060 pg m⁻³ (470 pg m⁻³, median) with TCPPs, EHDPP and TiBP exhibiting the higher median concentrations (~110, 100 and 85 pg m⁻³, respectively). Spring generally exhibited the lowest concentrations, probably linked to the influence of local meteorological conditions and air mass trajectories to a lesser extent. Non-chlorinated OPEs generally predominated, in contrast to the most common reported situation in marine environments (i.e. higher abundance of chlorinated OPEs) pointing to the relevance of local OPE sources in the study area. TiBP levels were generally higher than those reported for other marine/coastal environments suggesting this OPE as a good tracer of local sources in Bizerte. Contrarily, the atmospheric levels of other abundant OPEs in the area (e.g. TCPP) seem to be in the range and/or lower than those reported for remote marine environments. These findings point to the interplay of different factors with solar irradiance (potentially enhancing atmospheric photochemical oxidation reactions) and meteorological conditions in the study area likely compensating potential local sources of some OPEs. Not all OPEs presented the same seasonality in terms of atmospheric concentrations and pattern. The estimated atmospheric dry deposition fluxes (∑₉OPEs) were 18–180 ng m⁻² d⁻¹. Up to ~9 kg y⁻¹ of OPEs (~1 kg y⁻¹ of new organic anthropogenic phosphorus coming from OPEs) can be loaded to the shallow and enclosed Bizerte lagoon (~130 km²), considered as the most important aquaculture area in Tunisia, with yet unknown implications for the environmental exposure and impacts in the ecosystem functioning.

[en] Highlights: • MPs in marine sediments have been published in at least 70 articles, at a total of 813 locations on all continents. • Areas studied are mainly in coastal environments, and the number of locations examined per study ranges from 1 to 72. • We recommend the use of a NaCl solution for the separation step. • A digestion step using an H₂O₂ solution and automatic identification are recommended The ubiquity of microplastics (MPs) has now been demonstrated throughout Earth's geographic areas in both terrestrial and marine environments. Marine ecosystems are the end point of the plastic waste cycle, and marine sediments are increasingly considered to be a sink for plastic debris, with possible deleterious effects on seafloor ecosystems. However, the low concentration of MPs in a complex matrix such as marine sediment makes their reliable analysis difficult. MP concentration in marine sediments is usually determined by various extraction procedures followed by optical, spectroscopy or mass spectrometry techniques, and are therefore hard to compare. Therefore, reliable determination of MPs in sediment is a challenging task. Here we present a short review on studies dealing with analytical determination protocols and MP detection in marine sediments and discuss the advantages of the different techniques used. This analysis of the literature reveals that most of the 70 studies were carried out in European and Asian coastal environments. The use of NaCl saturated solution, hydrogen peroxide (H₂O₂) and Fourier transform infrared spectroscopy (FTIR) are by far the most-used techniques for the different steps of separation, digestion and identification, respectively. Based on this body of literature, we present recommendations and suggestions for future research in order to increase the reliability of results and to facilitate inter-comparison. The use of NaCl saturated and H₂O₂ solution is strongly recommended for the separation and digestion steps, respectively, whereas during the filtration step it is necessary to choose filter type based on the identification technique. More thorough investigation is needed to establish a systematic protocol for MP identification. A combination of techniques would permit to identify all items, and personal bias could be avoided if automatic identification was implemented. Nanoplastics (NP) occurrence in marine sediments is also discussed, although no data are available to date.

[en] Highlights: • Estimation of DMP, DEP, DiBP, DnBP, BzBP and DEHP concentration at Bay of Marseille. • One year PAEs observations (2014) in the Bay of Marseille. • Variation of PAE composition from surface to the bottom water. • High PAEs concentration close to deep and bottom water. Phthalic Acid Esters (PAEs) are a group of emerging organic contaminants that have become a serious issue because of their ubiquitous presence and hazardous impact on the marine environment worldwide. Seawater samples were collected monthly from December 2013 to November 2014 in the northwestern Mediterranean Sea (Marseille Bay). The samples were analyzed for dissolved organic carbon (DOC) as well as the molecular distribution of dissolved PAEs by using solid phase extraction followed by gas chromatography and mass spectrometry (GC/MS) analyses. The results demonstrated the occurrence of six PAEs, including dimethyl phthalate (DMP), diethyl phthalate (DEP), di-isobutyl phthalate (DiBP), di-n-butyl phthalate (DnBP), benzylbutyl phthalate (BzBP) and diethylhexyl phthalate (DEHP), with total concentrations ranging from 130 to 1330 ng L^{− 1} (av. 522 ng L^{− 1}). In Marseille Bay, the highest concentrations were detected in the bottom water from June to November 2014 and in the whole water column during the winter mixing period. This result suggests that resuspension of PAE-rich sediment, in relation to the accumulation of plastic debris above the seabed, or the higher degradation rate in the upper layer of the water column, plays a significant role in the PAE dynamics in coastal water. DEHP was the most abundant PAE in all of the surface samples and the summer bottom samples, followed by DiBP and DnBP, which also represent the largest fractions in the other bottom samples.

[en] Highlights: • High ∑₇PAE concentrations detected in zooplankton (up to 47 μg g⁻¹ dw). • Zooplankton sized 150–500 μm most concerned by chemical contamination. • Several PAEs & OPEs (e.g. EHDPP) have field-derived bioconcentration factors >5000. • No correlation between OPE & PAE concentrations and MP abundance in seawater. In this study, surface seawater, sediment and zooplankton samples were collected from three different sampling stations in Marseille Bay (NW Mediterranean Sea) and were analyzed for both microplastics and organic plastic additives including seven phthalates (PAEs) and nine organophosphate esters (OPEs). PAE concentrations ranged from 100 to 527 ng L⁻¹ (mean 191 ± 123 ng L⁻¹) in seawater, 12–610 ng g⁻¹ dw (mean 194 ± 193 ng g⁻¹ dw) in sediment and 0.9–47 μg g⁻¹ dw (mean 7.2 ± 10 μg g⁻¹ dw) in zooplankton, whereas OPE concentrations varied between 9 and 1013 ng L⁻¹ (mean 243 ± 327 ng L⁻¹) in seawater, 13–49 ng g⁻¹ dw (mean 25 ± 11 ng g⁻¹ dw) in sediment and 0.4–4.6 μg g⁻¹ dw (mean 1.6 ± 1.0 μg g⁻¹ dw) in zooplankton. Microplastic counts in seawater ranged from 0 to 0.3 items m⁻³ (mean 0.05 ± 0.05 items m⁻³). We observed high fluctuations in contaminant concentrations in zooplankton between different sampling events. However, the smallest zooplankton size class generally exhibited the highest PAE and OPE concentrations. Field-derived bioconcentration factors (BCFs) showed that certain compounds are prone to bioaccumulate in zooplankton, including some of the most widely used chlorinated OPEs, but with different intensity depending on the zooplankton size-class. The concentration of plastic additives in surface waters and the abundance of microplastic particles were not correlated, implying that they are not necessarily good indicators for each other in this compartment. This is the first comprehensive study on the occurrence and temporal variability of PAEs and OPEs in the coastal Mediterranean based on the parallel collection of water, sediment and differently sized zooplankton samples.

[en] Highlights: • A high-specific method for isolation of carbohydrates for stable carbon analysis and radiocarbon dating was established. • Carbohydrates were purified by cation exchange chromatography. • Carbohydrates were identified by Q-TOF-LC/MS and analyzed by EA-IRMS (δ¹³C) and EA-AixMICADAS (Δ¹⁴C). • The purification procedure produced very low blanks and did not affect carbohydrate isotopic signature. -- Abstract: Carbohydrates are among the most abundant organic molecules in both aquatic and terrestrial ecosystems; however, very few studies have addressed their isotopic signature using compound-specific isotope analysis, which provides additional information on their origin (δ¹³C) and fate (Δ¹⁴C). In this study, semi-preparative liquid chromatography with refractive index detection (HPLC-RI) was employed to produce pure carbohydrate targets for subsequent offline δ¹³C and Δ¹⁴C isotopic analysis. δ¹³C analysis was performed by elemental analyzer-isotope ratio mass spectrometer (EA-IRMS) whereas Δ¹⁴C analysis was performed by an innovative measurement procedure based on the direct combustion of the isolated fractions using an elemental analyzer coupled to the gas source of a mini carbon dating system (AixMICADAS). In general, four successive purifications with Na⁺, Ca²⁺, Pb²⁺, and Ca²⁺ cation-exchange columns were sufficient to produce pure carbohydrates. These carbohydrates were subsequently identified using mass spectrometry by comparing their mass spectra with those of authentic standards. The applicability of the proposed method was tested on two different environmental samples comprising marine particulate organic matter (POM) and total suspended atmospheric particles (TSP). The obtained results revealed that for the marine POM sample, the δ¹³C values of the individual carbohydrates ranged from −18.5 to −16.8‰, except for levoglucosan and mannosan, which presented values of −27.2 and −26.2‰, respectively. For the TSP sample, the δ¹³C values ranged from −26.4 to −25.0‰. The galactose and glucose Δ¹⁴C values were 19 and 43‰, respectively, for the POM sample. On the other hand, the levoglucosan radiocarbon value was 33‰ for the TSP sample. These results suggest that these carbohydrates exhibit a modern age in both of these samples. Radiocarbon HPLC collection window blanks, measured after the addition of phthalic acid (¹⁴C free blank), ranged from −988 to −986‰ for the abovementioned compounds, indicating a very small background isotopic influence from the whole purification procedure. Overall, the proposed method does not require derivatization steps, produces extremely low blanks, and may be applied to different types of environmental samples.

[en] Highlights: • ∑₃₄PAH 0.5–18 ng m⁻³, ∑₂₀PCB 0.3–11 pg m⁻³, ∑₆OCP 0.2–4 pg m⁻³ in Bizerte aerosols. • Dominance of BbF, BeP, IcdP, BghiP (PAHs), CB 138, 153, 180 (PCBs) and DDT (OCPs). • Highest concentrations and dry deposition fluxes in winter due to combustion inputs. • Estimated carcinogenic risks below acceptable risk level of 10⁻⁶, except in winter. The aim of this study was to assess, for the first time, the concentrations, sources, dry deposition and human health risks of polycyclic aromatic hydrocarbons (PAHs), aliphatic hydrocarbons (AHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in total suspended particle (TSP) samples collected in Bizerte city, Tunisia (North Africa), during one year (March 2015–January 2016). Concentrations of PAHs, AHs, PCBs and OCPs ranged 0.5–17.8 ng m⁻³, 6.7–126.5 ng m⁻³, 0.3–11 pg m⁻³ and 0.2–3.6 pg m⁻³, respectively, with higher levels of all contaminants measured in winter. A combined analysis revealed AHs originating from both biogenic and petrogenic sources, while diesel vehicle emissions were identified as dominant sources for PAHs. PCB potential sources included electronic, iron, cement, lubricant factories located within or outside Bizerte city. The dominant OCP congeners were p,p′-DDT and p,p′-DDE, reflecting a current or past use in agriculture. Health risk assessment showed that the lifetime excess cancer risk from exposure to airborne BaP was negligible in Bizerte, except in winter, where a potential risk to the local population may occur.

[en] Highlights: • First study of the PAEs and OPEs occurrence in sediments of the Gulf of Lion • DEHP and DnBP being identified as predominant PAEs • TDCP and TiBP are predominant OPEs in the area. • Port-based industrial activities and urban pressures are dominant sources. • Additive concentration decreases from shore to offshore at Rhône River discharge area. Seven phthalate (PAEs) and nine organophosphate esters (OPEs) were measured in surface sediments across the Gulf of Lion (NW Mediterranean Sea) at twelve stations characterized by different anthropogenic signatures. ∑PAEs and ∑OPEs concentrations ranged from 2 to 766 ng/g DW (av. 196 ng/g DW) and from 4 to 227 ng/g DW (av. 54 ng/g DW), respectively. Our analysis of the potential sources of these organic plastic additives in sediments of the Gulf of Lion suggests that the dominant factors affecting their occurrence and environmental distribution are port-based industrial activities and urban pressures. Indeed, the highest ∑PAEs and ∑OPEs concentrations were found close to the ports of Toulon and Marseille (Estaque) and at the sites impacted by the Marseille metropolitan area (i.e. at the outlets of the waste water treatment plant at Cortiou and at the mouth of the Huveaune River). The lowest levels were generally found in protected areas (e.g. Port-Cros) and at sites relatively far from the coast. DEHP was seen to be the most abundant PAE while TDCP, TEHP and TiBP were the most abundant OPEs in the area. Our results also expose the contribution of additives entering the Gulf of Lion via sedimentary material from the Rhône River, with positive correlations between the total organic carbon (TOC) content in the sediment and the ∑PAEs and ∑OPEs concentrations. However, additive concentrations decreased from shore to offshore in the Rhône River discharge area, indicating an efficient dilution of the contaminants accumulated at the river mouth area.