Legacy and emerging organic contaminants: Levels and profiles in top predator fish from the western Indian Ocean in relation to their trophic ecology.

Tuna and billfish are large pelagic fish of ecological importance in open oceans. As top predators with a long lifespan, they are prone to exposure to various contaminants such as persistent organic pollutants (POPs) and contaminants of emerging concern. In this study, three pollutant families were investigated, including polychlorinated biphenyls (PCBs), organochlorinated pesticides (OCPs) and perfluoroalkyl substances (PFASs), including perfluorooctane sulfonate (PFOS) and perfluorocarboxylic acids (PFCAs). Contamination was investigated in individuals from three tropical tuna species, namely bigeye (Thunnus obesus), skipjack (Katsuwonus pelamis) and yellowfin (Thunnusalbacares) tunas and the billfish swordfish (Xiphias gladius), collected from various areas of the western Indian Ocean (WIO) in 2013-2014. Contamination levels and profiles were examined in fish muscle, together with biological parameters (fish length / age, sex, lipid content) and ecological tracers (carbon and nitrogen stable isotopes). POP levels were low in all species in comparison to other locations worldwide, revealing a low impact of anthropogenic organic contaminants in the WIO. A predominance of OCPs (especially DDTs) versus PCBs was highlighted in all species; PFASs were predominant over chlorinated POPs in tunas. Among the studied PFASs, long-chain PFCAs were found to prevail over PFOS in all species. Organic contaminant profiles differed across species according to their foraging habitat; swordfish and bigeye tuna, which both feed in deep oceanic layers, showed similarities in their contaminant profiles. Geographically, the distinct DDT profiles of fish from the Mozambique Channel suggested an exposure to different DDT sources, in line with regional use of this insecticide and coupled with an extended residence time of fish in the Channel. To our knowledge, the data presented here are among the first obtained for legacy and emerging organic contaminants in various species of large pelagic predators from the WIO.

Tissue-specific distribution and maternal transfer of polybrominated diphenyl ethers (PBDEs) and their metabolites in adult common sole (Solea solea L.) over an entire reproduction cycle.

Tissue-specific accumulation and distribution of polybrominated diphenyl ethers (PBDEs) and their debrominated metabolites were studied in common sole (Solea solea) over an entire reproduction cycle. The fish were dietary-exposed to selected PBDEs in laboratory-controlled conditions for one year. Fish of both sexes were sampled throughout the reproduction cycle and their muscle, liver, viscera, carcass, skin and gonads (female) were analysed for total lipid content, PBDEs and their debrominated metabolites. On a wet weight basis, the concentrations of most spiked congeners showed an increase at the end of the exposure time in the whole body of fish of both sexes. Conversely, BDE-99 and BDE-209 - the two most highly metabolized congeners - did not show a similar increase, while their debrominated metabolites exhibited a linear increase over time. Biomagnification factors (BMFs) calculated in whole body were > 1 for all PBDEs except BDE-99 (0.89 ± 0.22) and BDE-209 (0.013 ± 0.006). BMFs were strongly correlated to apparent assimilation efficiencies, which ranged from 1.6% ± 0.7% (BDE-209) to 88% ± 11% (BDE-100). Fish carcass was the most predominant storage compartment for all PBDEs except BDE-209 in both male and female fish, followed by skin, muscle, female gonads, liver and visceral tissue. BDE-209 showed a different distribution and was stored more predominantly in the liver, viscera and female gonads than other congeners, probably due to its transport with lipoproteins. All PBDEs except BDE-209 showed equilibrium partitioning between the liver and other studied compartments, while BDE-209 showed a higher affinity with blood-enriched tissues, leading to higher liver / carcass, skin and muscle concentration ratios. Visceral tissue and liver exhibited the most pronounced differences in terms of concentration variations between sexes and over time. In females, both tissues showed a significant decrease in most PBDE concentrations (ww) and TLC in March during the spawning season, with low inter-individual variability, reflecting the striking utilisation of lipids by females for reproduction at this time. In males, no differences were found in concentrations in these compartments over time and a high inter-individual variability was observed. Maternal transfer of PBDEs from gonad to eggs was constant, regardless of spawn rank in the spawning season. Egg / gonad PBDE concentration ratios (in lw) were 1.3 ± 0.7 for all congeners and 2.6 ± 0.3 for BDE-209, suggesting a higher transfer of this congener from gonads to eggs.

Organophosphate ester additives and microplastics in benthic compartments from the Loire estuary (French Atlantic coast).

We report the first empirical confirmation of the co-occurrence of organophosphate esters (OPEs) additives and microplastics (MPs) in benthic compartments from the Loire estuary. Higher median concentrations of MPs (3387 items/kg dw), ∑13tri-OPEs (12.0 ng/g dw) and ∑4di-OPEs (0.7 ng/g dw) were measured in intertidal sediments with predominance of fine particles, and under higher anthropogenic pressures, with a general lack of seasonality. Contrarily, Scrobicularia plana showed up to 4-fold higher ∑tri-OPE concentrations in summer (reaching 37.0 ng/g dw), and similar spatial distribution. Polyethylene predominated in both compartments. Tris(2-ethylhexyl) phosphate (TEHP), its degradation metabolite (BEHP) and tris-(2-chloro, 1-methylethyl) phosphate (TCIPP) were the most abundant OPEs in sediments, while TCIPP predominated in S. plana. The biota-sediment accumulation factors suggest bioaccumulation potential for chlorinated-OPEs, with higher exposure in summer. No significant correlations were generally found between OPEs and MPs in sediments suggesting a limited role of MPs as in-situ source of OPEs.

A large diversity of organohalogen contaminants reach the meso- and bathypelagic organisms in the Bay of Biscay (northeast Atlantic).

Deep-sea ecosystems play a key role in the cycling and vertical transfer of matter and energy in oceans. Although the contamination of deep-sea demersal and benthic organisms by persistent organic pollutants has been proven, deep pelagic species have been far less studied. To fill these gaps, we studied the occurrence of a large variety of hydrophobic organic contaminants including polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), legacy and alternative brominated flame retardants (BFRs) and per- and polyfluoroalkyl substances (PFASs) in crustaceans and fish species collected in the Bay of Biscay, northeast Atlantic. The results highlighted the global predominance of PCBs in fish, followed by OCPs, PFASs and PBDEs, with highly variable concentrations among species. Most of the chlorinated or brominated contaminants showed increasing concentrations with increasing δ15N values, while most PFASs showed inverse trends. The contaminant profiles and diagnostic ratios revealed species-specific metabolic capacities and peculiar contribution of highly-brominated BFRs.

Legacy and emerging organic contaminants in two sympatric shark species from Reunion Island (Southwest Indian Ocean): Levels, profiles and maternal transfer.

The contamination of tiger sharks (Galeocerdo cuvier) and bull sharks (Carcharhinus leucas) by legacy persistent organic pollutants (POPs) and emerging organic contaminants was investigated in specimens from Reunion Island (Southwest Indian Ocean) in 2018 and 2019. Contamination levels were determined in the muscle of adult individuals of both sexes in relation to biological and trophic parameters. Maternal transfer was additionally investigated in one set of embryos in each species. Polychlorinated biphenyl (PCB), organochlorinated pesticide (OCP) and perfluoroalkylated substance (PFAS) concentrations were 2597 ± 2969, 785 ± 966 and 267 ± 194 pg g-1 ww, respectively, in bull sharks, and 339 ± 270, 1025 ± 946 and 144 ± 53 pg g-1 ww in tiger sharks. The results highlighted higher PCB contamination, and by the heavier congeners, in adult bull sharks versus tiger sharks. The significant differences found in PCB profiles and concentrations suggest that the two species are exposed to different contamination sources. As bull sharks rely on a more coastal habitat for feeding, their higher contamination by PCBs suggests the occurrence of local PCB sources. DDT concentrations were similar in both species, suggesting a more homogeneous contamination on the scale of the Southwest Indian Ocean. Female bull sharks showed lower OCP and PCB concentrations than males, while this trend was not observed in tiger sharks. The ratio of chlorinated contaminants in muscle between the mother and her embryos was related to molecule hydrophobicity in bull shark but not in tiger shark, suggesting that shark mode of gestation, known to be different in the two species, is a key driver of organic contaminant maternal transfer. Finally, the results show that organic contaminant levels in the studied species were lower than those of other shark species in the Southern Hemisphere, related to the limited urbanization and industrialization of Reunion Island.

Tissue-specific bioaccumulation of a wide range of legacy and emerging persistent organic contaminants in swordfish (Xiphias gladius) from Seychelles, Western Indian Ocean.

Swordfish (Xiphias gladius) is a major marine resource of high economic value to industrial and artisanal fisheries. As a top predator with a long lifespan, it is prone to accumulate high levels of contaminants. The bioaccumulation of a wide range of both legacy and emerging persistent organic contaminants was investigated in the muscle, liver and gonads of swordfish collected from the Seychelles, western Indian Ocean. The detection of all target contaminants, some at frequencies above 80%, highlights their widespread occurrence, albeit at low levels. Mean concentrations in muscle were 5637, 491 and 331 pg g-1 ww for organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and perfluoroalkyl substances (PFASs), respectively. ∑BFR mean concentrations were far below, i.e. 47 pg g-1 ww. The data are among the first obtained for such a high diversity of contaminants in an oceanic top predator worldwide and constitute a benchmark of the contamination of Indian Ocean ecosystems.

The aryepiglottic fold as a rare location of adenoid cystic carcinoma.

We report one case of a mass in the aryepiglottic fold seen on CT, which proved to be an adenoid cystic carcinoma. There was nothing specific about the imaging characteristics that would allow it to be confidentially differentiated from squamous cell carcinoma.

Computerized tomography of the glottis after intracordal autologous fat injection.

According to the committee on speech, voice, and swallowing disorders of the American Academy of Otolaryngology-Head and Neck Surgery, various surgical methods such as laryngeal framework surgery, laryngeal re-innervation, and injection laryngoplasty might be used to palliate inferior laryngeal nerve paralysis. In the present case report we document the survival and exact location of the boluses of autologous fat in one patient in whom this material was used for injection laryngoplasty.

Visibility of cranial nerves at MRI.

In order to assess the value of MRI in the depiction of intracranial nerves, we retrospectively reviewed 60 patients investigated over a 2-year period. The purposes of this study were: 1) to determine the score of MRI in detecting cranial nerves III to XII, and 2) to establish accurate landmarks for easy detection of these nerves. Cranial nerves III, V, VII and VIII are well seen (70 to 100%), very often on axial, sagittal and coronal sections. Nerves IX to XII are correctly studied only on axial planes (81 and 83%), but it is difficult to distinguish between the vagus nerve and the glossopharyngeal and spinal nerves. Due to their oblique direction and small size, nerves IV and VI are seldom visualized. The most important landmarks are the chiasma, the colliculi, Meckel's cavity, the internal auditory canal, the jugular foramen, the hypoglossal canal and the brainstem structures. We suggest the following scanning technique: short spin-echo sequences (TR 600 ms, TE 20 ms), 3 to 5 mm thick contiguous sections, 16 to 20 cm field of view with 4 or 2 excitations respectively, 256 x 256 matrix, and at least one acquisition plane (axial plane), but preferably two or three planes. MRI is a sensitive examination in the recognition of cranial nerves. It should be the first-step exploratory procedure in patients with cranial nerve pathology.

[The normal cranial nerves in MRI. Description and visualization frequency]. / Les nerfs crâniens normaux en IRM. Description et fréquence de visualisation.

In order to assess the value of MR in the depiction of intracranial nerves, we retrospectively reviewed 60 patients investigated over a period of 2 years. The aim of this study was: 1) to assess the score of MR in the detection of cranial nerves III to XII; 2) to determine accurate landmarks allowing for easy detection of those cranial nerves. Cranial nerves III, V, VII, VIII are well seen (70 to 100%), very often in both axial, sagittal and coronal sections. Nerves IX to XII are correctly studied only on axial planes [81 and 83%), but it is difficult to distinguish between the vagal nerve and the glossopharyngeal and spinal nerves. Due to their oblique direction and small size, fourth and sixth nerves are rarely visualized. The more important landmarks are the chiasma, the colliculi, the Meckel's cave, the internal auditory canal, the jugular foramen, the hypoglossal canal and the different brainstem structures. We suggest the following scanning protocol: short spin echo sequences (TR = 600 ms, TE = 20 msec), 3 to 5 continuous sections, 16 to 20 cm field of vue with respectively 4 or 2 excitations, 256 x 256 matrix, with at least one acquisition plane (axial), but preferably two or three planes. Thus MR is sensitive exam in the recognition of cranial nerves, and it must be the first step exam in patients presenting with cranial nerve disease.

[Cystic lymphangioma of the neck and mediastinum: are there acquired forms? Report of 37 cases]. / Les lymphangiomes kystiques du cou et du médiastin: existe-t-il des formes acquises? A propos de 37 cas.

BACKGROUND: In 9 out of 10 cases, lymphangiomas are observed during the first years of life, generally located in the neck. Rare lymphangiomas have been reported in adults, usually in an intrathoracic localization, raising the hypothesis of an acquired origin. PATIENTS AND METHODS: A retrospective analysis of patients undergoing surgery for lymphanioma of the neck or mediastinum was conducted. Pathology reports, clinical data and medical imaging (CT) were reviewed and operative and post-operative findings were analyzed in order to determine whether the cases could be divided into congenital and non-congenital forms. RESULTS: Data were obtained on 37 patients (23 men and 14 women, mean age 45 years, range 8-77). Four lesions (11%) were located in the neck: 3 in children and one in an elderly subject (77 yrs). Thirty-three tumors (89%) were located in the mediastinum. In 5 cases, the tumor was located in the phrenic nodes of the anterior mediastinum. These lymphangiomas occurred in young adults, had a CT density less than liquid with enhancement after contrast injection, and had a malformative vascular component proven anatomically and histologically (hemolymphangioma). These elements favored a congenital orgin. In 28 cases (76.6%) the tumor involved nodes in the posterior or middle mediastinum. They occurred in older adults and were purely liquid with no vascular component. These lymphangiomas were undoubtedly acquired. CONCLUSION: In children, adolescents and young adults, lymphagiomas are found in the neck or anterior mediastinum and have a tissular component. These tumors should be considered as congenital lymphangiomas. In older adults, lymphangiomas are found in the posterior or middle mediastinum and are purely liquid cysts suggesting an acquired origin.

[Radiological surveillance of operated ethmoidal cancers. Practical points]. / Surveillance radiologique des cancers ethmoïdaux opérés. Quelques points pratiques.

Radiological follow-up of ethmoidal neoplasms is not clearly established in terms of imaging modalities (CT, MRI) or periodicity. This paper, based on 4 typical cases, tries to describe the main imaging features of this radiological follow-up. Initial CT 3 to 6 months after surgery is essential, being the reference examination. It can show postoperative bone changes. During follow-up, a CT scanner every 6 months seems sufficient. For the image interpretation, a comparison with the two previous CT is mandatory. Any bone destruction must be considered as suspicious, even if very small. MRI should be performed in case of sphenoidal opacity, in order to differentiate between tumor recurrence and retentional fluid. MRI is also necessary and useful when the tumor presents an intradural or intracranial extension.

[Articulatory compensation after supracricoid partial laryngectomy with cricohyoidoepiglottopexy]. / Compensations articulatoires après laryngectomie partielle supracricoïdienne avec cricohyoïdoépiglottopexie.

OBJECTIVES: The consequences of the modification of the glottis and the shortening of the vocal tract after supracricoid partial laryngectomy (SCPL) with cricohyoidoepiglottopexy (CHEP) were investigated prospectively on ten patients. An acoustic analysis of the transfer function of the vocal tract was performed by measuring the formant frequencies of the [a] and [i] vowels. The articulation compensatory mechanisms of the vocal tract were observed with cinefluoroscopy in order to evaluate the phonation and articulation constraints. PATIENTS AND METHODS: Ten male patients were recorded before surgery and at six, 12 and 18 months after surgery. The results were compared with those of 10 male normal speakers having the same range of age. For the acoustic measures, we tracked the three first formant frequencies of the cardinal vowels [a] and [i], before and after surgery. Articulation investigation was performed with cinefluoroscopy for the vowels [a] and [i] uttered by two of the 10 patients. RESULTS: For the [a] vowel, the acoustic analysis showed higher values for all three formants, related to the shortening of the vocal tract after surgery. For the [i] vowel, the lowering of the second formant frequencies after surgery was related to an articulatory compensation. Cinefluoroscopy confirmed the shortening of the vocal tract, the tongue-root retraction for voicing and the anterior position of the tip of the tongue for the [i] vowel. CONCLUSIONS: The consequences of the shortening of the vocal tract after SCPL with CHEP can be evaluated, non invasively, by means of acoustic analysis. The understanding of the articulation compensatory mechanisms resulting from voicing constraints should help voice rehabilitation and improve oral communication in such patients.

[Is facial nerve visible on magnetic resonance imaging?]. / Le nerf facial est-il visible en IRM?

The internal architecture of the parotid gland was studied by nuclear magnetic resonance (NMR) imaging, particular attention being paid to the intra-parotid portion of the facial nerve. Currently available apparatuses provide high resolution images of previously poorly elucidated anatomic details. Certain authors consider that images in the axial plane in T1 allow direct visualization of the facial nerve and its branches in the form of low frequency linear signals within the gland. The present study, based on radio-anatomic correlations and date determined in a healthy volunteer, demonstrated that these structures correspond in fact to segments of the excretory canal tree, the facial nerve and its branches being invisible on NMR imaging. It is not possible, therefore, to determine the location of a parotid tumor in relation to these nerve elements using this imaging technique.

[False radiologic pneumoperitoneum. The value of emergency abdominal computed tomography]. / Faux pneumopéritoine radiologique. Intérêt du scanner abdominal en urgence.

We report 2 cases of false pneumoperitoneum. The diagnosis was suspected on an upright chest or abdominal plain films. The absence of clinical signs and symptoms of peritoneal irritation suggested a wrong radiological diagnosis. Emergency CT scan definitely eliminated a pneumoperitoneum and suggested the right diagnosis in both cases. This exam may play the decisive role in preventing needless emergency laparotomy.