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Background: In older patients with cancer, depression is difficult to assess because of its heterogeneous clinical expression. The 4‐item version of the Geriatric Depression Scale (GDS‐4) is quick and easy to administer but has not been validated in this population. The present study was designed to test the diagnostic performance of the GDS‐4 in a French cohort of older patients with cancer before treatment. Materials and Methods: Our cross‐sectional analysis of data from the Elderly Cancer Patient cohort covered all patients with cancer aged ≥70 years and referred for geriatric assessment at two centers in France between 2007 and 2018. The GDS‐4's psychometric properties were evaluated against three different measures of depression: the geriatrician's clinical diagnosis (based on a semistructured interview), the 4th edition of the Diagnostic and Statistical Manual of Mental Disorders, and a cluster analysis. The scale's sensitivity, specificity, positive and negative likelihood ratios, and area under the receiver operating characteristic curve (AUROC) were calculated. Results: In a sample of 2,293 patients (median age, 81 years; women, 46%), the GDS‐4's sensitivity and specificity for detecting physician‐diagnosed depression were, respectively, 90% and 89%. The positive and negative likelihood ratios were 8.2 and 0.11, and the AUROC was 92%. When considering the subset of patients with data on all measures of depression, the sensitivity and specificity values were, respectively, ≥90% and ≥72%, the positive and negative likelihood ratios were, respectively, ≥3.4 and ≤ 0.11, and the AUROC was ≥91%. Conclusion: The GDS‐4 appears to be a clinically relevant, easy‐to‐use tool for routine depression screening in older patients with cancer. Implications for Practice: Considering the overlap between symptoms of cancer and symptoms of depression, depression is particularly difficult to assess in older geriatric oncology and is associated with poor outcomes; there is a need for a routine psychological screening. Self‐report instruments like the 4‐item version of the Geriatric Depression Scale appears to be a clinically relevant, easy‐to‐use tool for routine depression screening in older patients with cancer. Asking four questions might enable physicians to screen older patients with cancer for depression and then guide them toward further clinical evaluation and appropriate care if required. Depression is associated with worse outcomes in older patients with cancer. This article evaluates the diagnostic performance of the French Geriatric Depression Scale (GDS‐4) in a French cohort of elderly patients before treatment for cancer. [ABSTRACT FROM AUTHOR]

Purpose: Abiraterone acetate combined with prednisone improves survival in metastatic castration-resistant prostate cancer (mCRPC) patients. This oral anticancer agent may result in drug-drug interactions (DDI). We aimed to evaluate the prevalence of DDI with abiraterone and the possible determinants for the occurrence of these DDI.Methods: We performed a single centre retrospective review from electronic medical records of mCRPC patients treated with abiraterone from 2011 to 2015. Potential DDI with abiraterone were identified using Micromedex and were categorized by a 4-point scale severity.Results: Seventy-two out of ninety-five mCRPC pts (median age: 77 years [68-82]) had comorbidities. The median number of drugs used per patient was 7 [5-9]. 66 potential DDI with abiraterone were detected in 49 patients (52%): 39 and 61% were classified as major and moderate DDI, respectively. In the univariate analysis, pain (p < 0.0001), hypo-albuminemia (p = 0.032), and higher ECOG performance status (PS) (p = 0.013) were significantly associated with a higher risk of DDI with abiraterone. Pain (p < 0.0001) and PS (p = 0.018) remained significant in the multivariate analysis.Conclusions: Polypharmacy is an issue among mCRPC patients. In our study, half of the patients have potential DDI with abiraterone. Patients with pain and poor PS are at higher risk of DDI with abiraterone. A medication review by a pharmacist is of crucial importance to prevent DDI with abiraterone. [ABSTRACT FROM AUTHOR]

Summary Flash flood events are responsible for large economic losses and lead to fatalities every year in France. This is especially the case in the Mediterranean and oversea territories/departments of France, characterized by extreme hydro-climatological features and with a large part of the population exposed to flood risks. The recurrence of remarkable flash flood events, associated with high hazard intensity, significant damage and socio-political consequences, therefore raises several issues for authorities and risk management policies. This study aims to improve our understanding of the hazard analysis process in the case of four remarkable flood events: March 1930, October 1940, January 1980 and November 1999. Firstly, we present the methodology used to define the remarkability score of a flood event. Then, to identify the factors leading to a remarkable flood event, we explore the main parameters of the hazard analysis process, such as the meteorological triggering conditions, the return period of the rainfall and peak discharge, as well as some additional factors (initial catchment state, flood chronology, cascade effects, etc.). The results contribute to understanding the complexity of the processes leading to flood hazard and highlight the importance for risk managers of taking additional factors into account. [ABSTRACT FROM AUTHOR]

Introduction Sunitinib is a multikinase inhibitor active in various cancers types including renal cancers and endocrine tumors. The study analyzed the influence of the lean body mass (LBM) and of pharmacogenetic variants on the exposure to sunitinib and its active metabolite, SU12662, and on sunitinib toxicity and clinical activity. Materials and Methods Exposure to sunitinib and SU12662 was assessed on days 10 and 21 during the first treatment cycle. Acute toxicity was graded using the NCI 4.0 CTCAE ver. 4.0. The LBM and 14 common single nucleotide polymorphisms in the CYP3A4/3A5, NR1I2, NR1I3, ABCB1, and ABCG2 genes were analyzed according to the drug exposure at day 10. Determinants (including sunitinib exposure and pharmacogenetic variants) for toxicities were assessed, as well as the relationship between drug exposure and survival in renal cancer patients. Results Ninety-two patients (60 % with renal cancer) were assessable for pharmacokinetics, toxicity and survival, and 66 for genetic analysis. The LBM ( p < 0.0001) and a polymorphism in the ABCG2 transporter (421C>A) ( p = 0.014) were two independent parameters accounting for the variability of composite (sunitinib + SU12662) exposure. Advanced age (OR = 1.47 [1.01-2.15], p = 0.048) and high sunitinib exposure (OR = 1.16 [1.05-1.28], p = 0.005) were independently associated with any grade ≥ 3 acute toxicity, and high SU12662 exposure was associated with grade ≥ 2 thrombocytopenia (OR = 1.27 [1.03-1.57], p = 0.028). A high composite area under the curve (AUC) >1,973 ng/mL∙h at day 21 was associated with a doubled survival (35.2 vs 16.7 months; log-rank p = 0.0051) in renal cancer patients. Conclusions This study indicates that LBM and drug monitoring may be helpful in the management of sunitinib-treated patients. [ABSTRACT FROM AUTHOR]

The increasing number of unfit patients calls for better risk assessment prior to initiating anti-tumor treatment. This is a major concern in the prevention and reduction of treatment-related complications. The aim of our study was to evaluate the nutritional status for the risk assessment of patients qualifying to receive the gemcitabine and oxaliplatin (GEMOX) regimen. This single-center, retrospective study examined baseline clinical and biological characteristics in a cohort of 165 unselected, consecutive cancer patients receiving GEMOX. Malnutrition was defined as either body mass index (BMI) <18.5 kg/m2, body weight loss >10% over 3 mo, or albuminemia <35 g/L. A total of 165 patients (median age 61 yr, PS 0–1: 71%) were studied. Malnutrition was seen in 43% of PS 0–1 patients, vs. 60% of PS 2 and 66% of PS 3 patients (P> 0.05). Median relative dose-intensity was 0.90 (0.17–1.04). GEMOX dose-intensity correlated negatively with loss of baseline weight (r = −0.24,P< 0.02). In patients who did not complete more than 2 cycles of chemotherapy, median PS (P< 0.01), mean C-reactive protein (CRP;P< 0.01), and mean albuminemia (P< 0.05) were, respectively, significantly higher, higher, and lower. Malnutrition is associated with a high risk of early discontinuance of treatment. Systematic basal evaluation of the nutritional status, including albuminemia and BMI, is recommended. [ABSTRACT FROM PUBLISHER]

Purpose: Ambulatory chemotherapy is patient friendly but may result in toxicity-induced unscheduled hospitalizations (TIUHs). This emerging issue may increase health care costs. We studied the cost effectiveness of a hospital-home monitoring program based on systematic iterative telephone calls after chemotherapy. Patients and Methods: We retrospectively evaluated the rates of chemotherapy-induced unscheduled hospitalizations in patients who were treated in August 2008. Patients were contacted by telephone 1 day before chemotherapy and on the second and eighth days after undergoing chemotherapy. Costs associated with TIUHs were calculated and compared with those of a cohort concomitantly treated using the standard follow-up procedure. Results: A total of 259 patients entered the hospital-home monitoring program. They were compared with 86 patients who had similar characteristics but underwent the standard treatment and follow-up procedure. Inclusion in the hospital-home monitoring program resulted in patients experiencing TIUHs approximately half as frequently as patients in the other group (2.4% v 4.9%; P < .01). Patients in the program experienced TIUHs for a median length of stay of 4 days, representing a nonsignificant reduction in duration of hospitalization (P not significant). Consequently, through a two-fold reduction in TIUH annual incidence, this program represents a reduction in unscheduled hospitalizations per year of 383 days, decreasing hospital costs by €201.468 ($292,468) per year. Conclusion: The hospital-home monitoring program is a cost-effective strategy for offering ambulatory chemotherapy treatment to patients with cancer. This program has become our standard procedure for ambulatory chemotherapy in patients with cancer. [ABSTRACT FROM AUTHOR]

Summary: Adherence to osteoporosis treatment is not satisfactory. Our study evaluated persistence and compliance with these treatments prescribed specifically in the context of a fracture liaison service (FLS), an internal health care network, and showed that this type of organization in our institution was associated with high level of adherence. Introduction: Medical management of patients with a fragility fracture has been improved by health care internal network or FLS organized in large hospitals. However, treatment effectiveness is not only related to larger initiation rate but also to better long-term adherence. Therefore, we evaluated persistence and compliance in the context of osteoporosis treatment initiated in our institution's FLS, among postmenopausal women with a peripheral fragility fracture. Methods: Patients with a specific osteoporosis treatment prescribed while visiting our FLS were contacted by phone to answer an evaluation questionnaire. A simplified questionnaire was sent to their general physicians when we were not able to reach patients on the phone. Results: Of the 279 selected patients, 155 were evaluated. Of them, 90.3% had actually started their treatment and 80% were still under treatment after 1 year. After 27.4 ± 11.7 months of follow-up, 67.7% of patients were persistent with their treatment. In addition, 87% of the persistent patients declared to respect both treatment posology and administration conditions. Occurrence of adverse events was the first cause of treatment interruption within the first 6 months. Conclusions: Our data showed a high level of persistence with osteoporosis treatment when initiation was performed in an FLS, even on a long-term basis. Since follow-up and renewal of treatment were under routine daily practise, our study underlines how important the first prescription conditions are and provides additional interest in medical care network such as FLS. [ABSTRACT FROM AUTHOR]

We investigated the impact of the implementation of a network of reference centers for sarcomas (NETSARC) on the care and survival of sarcoma patients in France since 2010. NETSARC (netsarc.org) is a network of 26 reference sarcoma centers with specialized multidisciplinary tumor boards (MDTBs), funded by the French National Cancer Institute (INCa) since 2010. Its aims are to improve the quality of diagnosis and care of sarcoma patients. Patients' characteristics, treatments, and outcomes are collected in a nationwide database. The objective of this analysis was to compare the survival of patients in three periods: 2010-2012 (non-exhaustive), 2013-2015, and 2016-2020. A total of 43 975 patients with sarcomas, gastrointestinal stromal tumors (GISTs), or connective tissue tumors of intermediate malignancy were included in the NETSARC+ database since 2010 (n = 9266 before 2013, n = 12 274 between 2013 and 2015, n = 22 435 in 2016-2020). Median age was 56 years, 50.5% were women, and 13.2% had metastasis at diagnosis. Overall survival was significantly superior in the period 2016-2020 versus 2013-2015 versus 2010-2012 for the entire population, for patients >18 years of age, and for both metastatic and non-metastatic patients in univariate and multivariate analyses (P < 0.0001). Over the three periods, we observed a significantly improved compliance to clinical practice guidelines (CPGs) nationwide: the proportion of patients biopsied before surgery increased from 62.9% to 72.6%; the percentage of patients presented to NETSARC MDTBs before first surgery increased from 31.7% to 44.4% (P < 0.0001). The proportion of patients with R0 resection on first surgery increased (from 36.1% to 46.6%), while R2 resection rate decreased (from 10.9% to 7.9%), with a better compliance and improvement in NETSARC centers. The implementation of the national reference network for sarcoma was associated with an improvement of overall survival and compliance to guidelines nationwide in sarcoma patients. Referral to expert networks for sarcoma patients should be encouraged, though a better compliance to CPGs can still be achieved. • The creation of nationwide network of reference centers in France was associated with improved survival of sarcoma patients. • The compliance to CPGs over 10 years and the quality of surgery nationwide increased significantly. • Improvement in compliance to CPG was seen both in and outside reference centers but the compliance was lower outside. • These observations support the systematic referral of sarcoma patients to a network of sarcoma reference centers. • Further work on improvement and monitoring of compliance to CPGs must be implemented. [ABSTRACT FROM AUTHOR]

Background: Metastatic leiomyosarcomas have a poor prognosis, and currently doxorubicin alone is used as the standard first-line treatment. Doxorubicin combined with trabectedin has shown promising results in phase 1 and 2 studies. We aimed to identify and compare the progression-free survival of patients with metastatic or unresectable uterine or soft tissue leiomyosarcoma treated with doxorubicin and trabectedin combined as first-line therapy versus doxorubicin alone in a phase 3 trial.Methods: LMS-04 was a randomised, multicentre, open-label, superiority phase 3 trial, which included patients from 20 centres of the French Sarcoma Group (anticancer centers or hospitals with an oncological unit) in France. Eligible patients were aged 18 years or older, had an Eastern Cooperative Oncology Group performance status of 0-1, and had metastatic or relapsed unresectable leiomyosarcomas that had not previously been treated with chemotherapy. Patients were randomly assigned (1:1), by means of an interactive web response system (permuted blocks of different sizes from two to six), to receive either intravenous doxorubicin alone (75 mg/m2) once every 3 weeks for up to six cycles or of intravenous doxorubicin (60 mg/m2) plus intravenous trabectedin (1·1 mg/m2) once every 3 weeks up to six cycles followed by maintenance with trabectedin alone. Surgery for residual disease was allowed in both groups after six cycles of treatment. Randomisation was stratified by tumour location (uterine vs soft tissue) and disease (locally advanced vs metastatic). The primary endpoint was progression-free survival assessed by blinded independent central review and according to Response Evaluation Criteria in Solid Tumours 1.1 criteria. Efficacy analyses were performed on all randomly assigned patients, based on the intention-to-treat principle. The safety population included all randomly assigned patients who received at least one cycle of treatment. This trial is registered with ClinicalTrials.gov, NCT02997358, and is closed to enrolment.Findings: Between Jan 18, 2017, and March 21, 2019, 150 patients were enrolled (67 with uterine leiomyosarcomas and 83 with soft tissue leiomyosarcomas) and included in the intention-to-treat population: 76 in the doxorubicin alone group and 74 in the doxorubicin plus trabectedin group. The median duration of follow-up was 36·9 months (IQR 30·0-43·2) in the doxorubicine group and 38·8 months (32·7-44·2) in the doxorubicin plus trabectedin group. Median progression-free survival was significantly longer with doxorubicin plus trabectedin versus doxorubicin alone (12·2 months [95% CI 10·1-15·6] vs 6·2 months [4·1-7·1]; adjusted hazard ratio 0·41 [95% CI 0·29-0·58]; p<0·0001). The most common grade 3-4 adverse events were neutropenia (ten [13%] of 75 patients in the doxorubicin alone group vs 59 [80%] in the doxorubicin plus trabectedin group), anaemia (four [5%] vs 23 [31%]), thrombocytopenia (0 vs 35 [47%]), and febrile neutropenia (seven [9%] vs 21 [28%]). Nine (12%) patients in the doxorubicin alone group and 15 (201%) patients in the doxorubicin plus trabectedin group has serious adverse events. There was only one treatment-related death, reported in the doxorubicin alone group (cardiac failure).Interpretation: Doxorubicin plus trabectedin in first-line therapy was found to significantly increase progression-free survival in patients with metastatic or unresectable leiomyosarcomas compared with doxorubicin alone, despite a higher but manageable toxicity, and could be considered an option for the first-line treatment of metastatic leiomyosarcomas.Funding: PharmaMar. [ABSTRACT FROM AUTHOR]

Cancer patients are a highly vulnerable group in the COVID-19 pandemic and it has been necessary for oncology units to adapt to this unexpected situation. We present our management of outpatients with cancer during the pandemic. We applied two major adaptations: extending the intervals between injections for maintenance therapy and protocol adaptation for patients with comorbidities. Between 17 March and 30 April 2020, 406 patients were treated in our outpatients department. Protocols were adapted for 94 (23.1%) patients. Among them, 49% had an extended interval between treatment administrations, 22.3% had modified protocols to reduce toxicity, 20.2% had therapeutic interruptions and 5.3% did not receive their treatment because of a COVID-19 infection. Overall, protocol adaptations concerned more than 20% of the patients. This pandemic was an opportunity for oncologists to re-examine the risk versus benefit balance of administering immunosuppressive treatment and highlighted that oncology daily routine should not be applied automatically. [ABSTRACT FROM AUTHOR]

Background: The treatment of chronic total occlusion of coronary arteries by percutaneous coronary intervention (CTO PCI) is one of the most representative technical advances in ischemic cardiomyopathy of last decade. However, how the complex histopathological remodeling and the new techniques affect healing processes after stent implantation remains unknown.Objective: The objective of the PERFE-CTO study is to analyze stent coverage, malapposition and other mechanical abnormalities 3 months after CTO recanalization using intravascular imaging.Methods: In a French prospective interventional multicenter study, stent strut coverage, acquired malapposition and neointimal hyperplasia (NIH) proliferation will be systematically assessed with 3 months angiogram control and intracoronary optical frequency domain imaging (OFDI) after successful CTO PCI of >20 mm in length. The impact of routine systematical intracoronary imaging after these complex procedures will also be evaluated by measuring the rate of significant mechanical abnormalities (strut malapposition, edge dissection, thrombus) that was undetected by fluoroscopy alone and by complementary PCI when needed. Secondarily, these data will be compared according to clinical characteristics, antiplatelet therapy use or desobstruction technique (antegrade vs. retrograde, true lumen vs. subintima). Each patient will undergo a one-year clinical follow-up. A total of 150 analyzed CTO lesions is expected.Conclusion: The PERFE-CTO study will provide essential understanding of the early history after CTO recanalization and the identification of inadequate evolution (stent thrombosis, restenosis or late delayed stent endothelization and cardiovascular outcomes) using intravascular imaging to improve long-term CTO results. [ABSTRACT FROM AUTHOR]

Purpose The outcome of desmoid-type fibromatosis (DTF) is unpredictable. Currently, a wait-and-see approach tends to replace large en bloc resection as the first therapeutic approach. Nevertheless, there are no validated factors to guide the treatment choice. Method We conducted a prospective study of 771 confirmed cases of DTF. We analysed event-free survival (EFS) based on the occurrence of relapse after surgery, progressive disease during the wait-and-see approach, or change in therapeutic strategy. Identification of prognostic factors was performed using classical methods (log-rank test and Cox model). Results Overall, the 2-year EFS was 56%; this value did not differ between patients undergoing an operation and those managed by the wait-and-see approach (53% versus 58%, p = 0.415). In univariate analysis, two prognostic factors significantly influenced the outcome: the nature of diagnostic sampling (p = 0.466) and primary location (p = 0.0001). The 2-year EFS was only 32% after open biopsy. The 2-year EFS was 66% for favourable locations (abdominal wall, intra-abdominal, breast, digestive viscera and lower limb) and 41% for unfavourable locations. Among patients with favourable locations, the 2-year EFS was similar in patients treated by both surgery (70%) and the wait-and-see approach (63%; p = 0.413). Among patients with unfavourable locations, the 2-year EFS was significantly enhanced in patients initially managed with the wait-and-see approach (52%) compared with those who underwent initial surgery (25%; p = 0.001). Conclusion The location of DTF is a major prognostic factor for EFS. If these findings are confirmed by independent analysis, personalised management of DTF must consider this easily obtained parameter. [ABSTRACT FROM AUTHOR]

Aims Recent data suggest that patients with pulmonary metastases from sarcomas might benefit from ablation of their metastases. Some data are available regarding osteosarcomas/angiosarcomas and lung metastases. The purpose of this study was to assess the efficacy of local ablative treatment on the survival of patients with oligometastases (one to five lesions, any metastatic site, any grade/histology) from sarcomas. Materials and Methods A multicentric retrospective study of the French Sarcoma Group was conducted in sarcoma patients with oligometastases who were treated between 2000 and 2012. Survival was analysed using multivariate sensitivity analyses with propensity scores to limit bias. Results Of the 281 patients evaluated, 164 patients received local treatment for oligometastases between 2000 and 2012. The groups' characteristics were similar in terms of tumour size and remission of the primary tumours. The median follow-up was 25.7 months; 129 (45.9%) patients had died at this point. The median overall survivals were 45.3 (95% confidence interval = 34–73) months for the local treatment group and 12.6 for the other group (95% confidence interval = 9.33–22.9). Survival was better among patients who received local treatment (hazard ratio = 0.47; 95% confidence interval = 0.29–0.78; P < 0.001). Subgroup analyses revealed similar findings in the patients with single oligometastases (hazard ratio = 0.48; 95% confidence interval = 0.28–0.82; P = 0.007); a significant benefit was observed for grade 3, and a trend was observed for grade 2. Conclusion Local ablative treatment seemed to improve the overall survival of the patients who presented with oligometastatic sarcomas, including soft tissue and bone sarcomas. The survival benefit remained after repeated local treatments for several oligometastatic events. Surgery yielded the most relevant results, but alternative approaches (i.e. radiofrequency ablation and radiotherapy) seemed to be promising. The relevance of these results is strengthened by our analysis, which avoided biases by restricting the population to patients with oligometastatic disease and used propensity scores. [ABSTRACT FROM AUTHOR]

A study was undertaken to examine cadmium accumulation in freshwater biofilm, its effects on biofilm development and on diatom community structure in laboratory experimental conditions. A suspension of a biofilm originated from the Riou-Mort River (South West France) was inoculated into three experimental units containing clean glass substrates under laboratory conditions. Settling and already developed biofilms were exposed to a Cd concentration of 100 microg L(-1). Metal accumulation (total and intracellular metal content) in biofilms, dry weight and ash-free dry mass, diatom cell density and diatom community composition were analyzed. Both total and intracellular Cd accumulated by the biofilm throughout the experiment increased with duration of metal exposure. Biofilms in the course of maturation were showed higher Cd content and less effective development than settled biofilms. However diatom communities in younger biofilms exposed to Cd increased their tolerance to Cd by a highly significant development of Nitzschia palea. In contrast, Cd exposure had different effect in installed biofilm and taxonomic composition. These results indicate that mature biofilm may limit Cd accumulation into its architecture and protect diatom communities from the effects of metals.

Goal, Scope and Background: The Gironde estuary is considered as a reference ecosystem with a large fish assemblage (75 species) and the presence of eleven diadromous species. However, geochemical studies and biomonitoring using oysters have shown high metal pollution levels. During the December 1999 hurricane, more than 5,000 young Siberian sturgeons (Acipenser baerii) accidentally escaped from a fish farm into the estuary, where this species had not been present until then., Methods: In 2002/2003, thirteen sturgeons were collected from the estuary and twelve were obtained from the fish farm, from the same initial batch. Analysis of five metals (cadmium, zinc, copper, lead, mercury) measured in the gills, muscle, liver and kidneys, revealed significantly higher levels of cadmium, lead and mercury in the sturgeon collected from the estuary compared with those from the fish farm., Results and Discussion: Metal analysis of the stomach contents of fish collected from the estuary and artificial food used in the fish farm indicated that dietary exposure might account for the differences observed. Nevertheless, metal concentrations in sturgeons that had spent about three years in the Gironde estuary may be considered low when compared with other species (mullets, eels) or with data in the literature regarding concentrations able to induce structural and functional perturbations in fish. As the introduced Siberian sturgeons live in the same place and feed on the same prey as the juveniles of the endangered A. sturio, our results indicate in the short-term that this strictly protected species does not appear to be much affected by the polymetallic pollution in the Gironde estuary. Marked differences in the concentrations of three metals (Cd, Pb, Hg) were established in four organs (gills, liver, skeletal muscle, kidneys) of Siberian sturgeons between specimens that had accidentally escaped into the Gironde estuary (France) during the December 1999 hurricane and were collected in March/June 2003 and specimens from the same initial batch at the fish farm., Recommendations and Perspectives: Based on these results, a programme will be set up, with sampling campaigns carried out in the estuary every two years, with systematic monitoring of age in order to check the origin of individuals, in conjunction with sampling of sturgeon from the fish farm. This programme will complement other studies on several biological species representative of the main trophic levels in the estuary, especially the plankton component, benthic macroinvertebrates and oysters.

The Petit-Saut hydroelectric reservoir was filled in 1994 on the Sinnamary River in French Guiana (Amazonian basin). Flooding of the equatorial rain forest led to anoxia in most of the water column and enhanced mercury methylation in the reservoir hypolimnion. We selected the benthivorous/omnivorous fish species Curimata cyprinoides to investigate total mercury and methylmercury (MeHg) bioavailability and bioaccumulation capacities in the reservoir and downstream in the Sinnamary River. Mercury concentrations in the dorsal skeletal muscle were 10-fold higher in fish from the downstream zone. Stomach contents and stable nitrogen and carbon isotope ratios showed that biofilms and the associated invertebrate communities represented important food sources at the two sites. The delta 13C measurements indicated that biofilms in the flooded forest zone of the reservoir consist of endogenous primary producers; downstream, they are based on exogenous organic matter and microorganisms, mainly from the anoxic layers of the reservoir. Total mercury and MeHg concentrations in the biofilms and associated invertebrates were much higher at the downstream site compared to concentrations at the reservoir. Our results clearly show the importance of MeHg export from the anoxic layers of this tropical reservoir. We conclude that differences between biofilm composition and MeHg concentrations in the ingested food could explain the marked differences observed between mercury levels in fish.

This study was designed to compare the metallothionein (MT) response capacity of two freshwater bivalves, Corbicula fluminea and Dreissena polymorpha, along an environmental gradient of polymetallic pollution. The bivalves were transplanted into 4 stations in southwestern France, with a cadmium and zinc pollution gradient. MT and metal concentrations were measured in the soft bodies of the clams and mussels over 2.5 months. In the zebra mussels, variations in MT concentrations were strictly correlated to progressive Cd and Zn bioaccumulation. In contrast, the faster response in the clams appeared positively correlated to Cd accumulation only, with the activation of efficient detoxification mechanisms which limited Cd bioaccumulation and reduced Zn concentrations over time. Nevertheless, despite stronger metal accumulation factors in D. polymorpha, C. fluminea revealed higher sensitivity of MT response along the pollution gradient.

Since the late 1980s, several studies have shown that human populations in the Amazon basin are exposed to high mercury levels in their fish diet. Gold mining, which releases the metal during the amalgamation process and erodes soils naturally rich in mercury, is regarded as the main contamination source. Here, we present the results of a comparative study of mercury distribution in the water and fish of two adjacent rivers in French Guiana, with and without gold mining activities. As a consequence of a marked difference in suspended particulate matter between the two systems, total mercury concentrations in unfiltered water samples were higher in the mined river (25.4-34.9 ng L(-1)) as compared to the reference one (2.1-5.4 ng L(-1)). Surprisingly, no significant differences were observed in mercury concentrations between 13 common fish species at upstream sites. In sharp contrast, mercury concentration of fish caught downstream a hydroelectric reservoir, where the two rivers flow, was up to 8-fold higher than that upstream. Mercury speciation measurements allowed one to relate these differences in fish to the water distribution of monomethylmercury, the mercury chemical species that biomagnifies along aquatic foodwebs. Indeed, mean dissolved monomethylmercury concentrations were low and similar in both rivers (0.03-0.06 ng L(-1)), while they were 10 times higher (up to 0.56 ng L(-1)) in the water outflowing the hydroelectric dam. Dissolved monomethylmercury determinations along a water column profile suggest that methylation of inorganic mercury occurs in the deep anoxic part in reservoir. We conclude that mercury mobilization related to gold mining is not solely sufficient to account for high concentrations in fish and that environmental conditions that favor mercury methylation, such as anoxia, are needed.

A 15-month experiment combining a geochemical survey of Cd, Cu, Zn and Hg with a bioaccumulation study for three filter-feeding bivalve species (oysters, Crassostrea gigas; cockles, Cerastoderma edule; and clams, Ruditapes philippinarum) was conducted in a breeding basin of the Nord Medoc salt marshes connected to the Gironde estuary, which is affected by historic polymetallic pollution. Regular manual surface measurements of temperature, salinity, pH and dissolved O(2) concentration and hourly multiprobe in situ measurements throughout several periods for 6-8 weeks were performed. The geochemical behavior of metals in water, suspended particulate matter and sediment and their ecotoxicological impact on the three bivalve species were evaluated by in situ exposure of juvenile oysters (water column) and adult cockles and clams (sediment surface). The physico-chemical parameters reflected seasonal variations and basin management. A distinct daily periodicity (except salinity) indicated intense photosynthesis and respiration. In summer, low dissolved O(2) saturations ( approximately 40-50%) occurred in the early morning at 30 cm above the sediment, whereas in depressions, the water column near the sediment surface was suboxic. Cadmium, Zn and Cu concentrations in suspended particulate matter exceeded typical estuarine values and were much higher than the homogeneously distributed concentrations in different depth ranges of the basin sediment. Particles collected in sediment traps showed intermediate metal concentrations close to sediment values. These results suggest trace metal recycling due to reductive dissolution under suboxic conditions at the sediment surface resulting in trace metal release to the water column and adsorption onto suspended particles. Dissolved Cd, Zn and Hg concentrations (e.g. 13-136 ng l(-1); 0.3-25.1 microg l(-1) and 0.5-2.0 ng l(-1), respectively) in the basin corresponded to the concentration range typically observed in the Gironde estuary, except for some maximum values attributed to metal recycling. In contrast, dissolved Cu concentrations (1.08-6.08 microg l(-1)) were mostly higher than typical estuarine values, probably due to recycled Cu complexation by dissolved organic matter. Growth, bioaccumulation rates and kinetics in the whole soft body of the bivalves were analyzed every 40 days. Although Cd bioaccumulation of oysters was lower in the basin than in the estuary during the same period (27,000 ng g(-1), dry weight and 40,000 ng g(-1), respectively) these values are largely above the new human consumption safety level (5000 ng g(-1), dw; European Community, 2002). For cockles and clams, Cd bioaccumulation was lower, reaching 1400 ng g(-1) and 950 ng g(-1), respectively. Similar results were obtained for Zn and Cu suggesting physiological differences between the species and/or differences in the exposure of the organisms due to physico-chemical conditions and metal distribution between dissolved and particulate phases. In contrast, Hg bioaccumulation was highest for cockles reaching bioconcentration factors of approximately 200,000, which even exceeded that of Cd in oysters (50,000) for the same exposition period. Nevertheless, Hg concentrations remained relatively low in the three bivalve species.

Total mercury concentrations (Hgt) have been determined in liver, kidneys, skeletal muscle, melon, stomach and intestine of 35 specimens of Stenella coeruleoalba stranded on French Atlantic and Mediterranean coasts. Very high mercury levels, with concentrations reaching 80 mg Hgt kg(-1) fresh weight (FW) in muscle and about 1500 mg Hgt kg(-1) FW in liver tissue, were observed. Liver has the highest concentration, followed by muscle and kidney. The lowest concentrations were found in the melon. The levels observed in the Mediterranean specimens are among the highest observed in marine organisms and confirm previous reports of high mercury levels in marine mammals from the Mediterranean. Comparison between Hgt accumulation levels in these two geographic groups of dolphins shows that Mediterranean individuals have much higher concentrations than specimens from the Atlantic. These differences provide additional confirmation for the higher Hgt concentrations observed previously in other pelagic species (tuna, sardine, anchovy, etc.) from the Mediterranean Sea. Taking into consideration the pelagic habitat of the dolphin and the local influence of anthropogenic mercury sources it seems reasonable to assume that the main source of the high mercury concentrations observed in Mediterranean biota is natural mercury deposits located in many regions of the Mediterranean basin.