Ulvan Lyases Isolated from the Flavobacteria Persicivirga ulvanivorans Are the First Members of a New Polysaccharide Lyase Family

International audienc

Iodine content in bulk biomass of wild-harvested and cultivated edible seaweeds: Inherent variations determine species-specific daily allowable consumption

This study represents a large-scale investigation into iodine contents in three commercially important and edible seaweed species from the North Atlantic: the brown algae Saccharina latissima and Alaria esculenta, and the red alga Palmaria palmata. Variability among and within species were explored in terms of temporal and spatial variations in addition to biomass source. Mean iodine concentration in bulk seaweed biomass was speciesspecific: Saccharina > Alaria > Palmaria. Iodine contents of Saccharina biomass were similar between years and seasons, but varied significantly between sampling locations and biomass sources. In Alaria and Palmaria, none of the independent variables examined contributed significantly to the small variations observed. Our data suggest that all three species are rich sources of iodine, and only 32, 283, or 2149 mg dry weight of unprocessed dry biomass of Saccharina, Alaria, or Palmaria, respectively, meets the recommended daily intake levels for most healthy humans.publishedVersio

Biomass soaking treatments to reduce potentially undesirable compounds in the edible seaweeds sugar kelp (Saccharina latissima) and winged kelp (Alaria esculenta) and health risk estimation for human consumption

acceptedVersio

Size distribution and number concentration of the 10nm-20um aerosol at an urban background site, Gennevilliers, Paris area

International audienceThe purpose of this study is to quantify the exposure of people to the submicronic particles, and especially ultrafine/nanoparticules (< 100 nm) at an urban background site in the Paris area. Since 2003, two particle sizers have been used every year for a winter five weeks campaign

Identification des sources et facteurs d'influence de la pollution aux particules ultrafines au niveau d'un site de fond parisien

National audienceThe French community involved in air quality monitoring early got interested in the measurement of submicronic particles. Since 2003 INERIS has carried out monitoring campaigns once or twice a year in an urban site located near Paris, enabling the constitution of a large hourly database. Besides air quality measurements, other variables have been introduced into the database: traffic and heating emissions provided by the local air quality monitoring agency (AIRPARIF) ; meteorological variables issued from monitoring or extracted from the meteorological MM5 model (height of the boundary layer). An exploratory study of the data collected from 2003 to 2007 has been performed. Two physically independent factors prove to play a significant role in the evolution of submicronic particle concentrations: emissions, especially traffic emissions, and atmospheric dispersion conditions.Depuis 2003, dans le cadre du LCSQA (www.lcsqa.fr), l'INERIS réalise un travail spécifique sur les particules submicroniques. En partenariat avec AIRPARIF, une des principales actions a pour objectif de documenter l'exposition en région parisienne [Godard, 2003]. Une campagne intensive de 5 semaines est organisée chaque année en période hivernale, au niveau de la station urbaine de fond d'AIRPARIF à Gennevilliers. Une base de données horaire est ainsi régulièrement élargie et enrichie par des éléments d'information liés aux sources et aux variables de dispersion. C'est le cas de la hauteur de la couche de mélange extraite du modèle météorologique MM5 model, et des inventaires d'émission concernant le trafic et le chauffage urbain (données AIRPARIF). Une analyse exploratoire a été menée sur les données concernant les campagnes de 2003 à 2007. Nous avons examiné la relation entre d'une part la concentration en nombre, et d'autre part les émissions et les paramètres météorologiques : suivi temporel, cycle journalier, coefficient de corrélation. Deux facteurs indépendants sont mis en évidence : d'une part les émissions et tout particulièrement le trafic automobile, d'autre part les conditions de dispersion atmosphérique

Variations in polyphenol and heavy metal contents of wild-harvested and cultivated seaweed bulk biomass: Health risk assessment and implication for food applications

Seaweeds are increasingly used in European cuisines due to their nutritional value. Many algal constituents, such as polyphenols, are important antioxidants and thus considered beneficial to humans. However, many seaweed species can accumulate heavy metals and exhibit potential health risks upon ingestion. We investigated temporal and spatial variations in polyphenol and heavy metal (As, Cd, Hg, Pb) concentrations of three edible seaweed species. The brown algae Saccharina latissima and Alaria esculenta, and the red alga Palmaria palmata were sourced from natural populations and aquaculture in the NE Atlantic and processed as bulk biomass mimicking industrial scales. The mean polyphenol content was species-specific (Alaria > Saccharina > Palmaria), and highest in winter (for Alaria and Saccharina) and spring (for Palmaria); inter-annual and spatial variations were marginal. Heavy metal concentrations varied between species and depended on collection site, but seasonal variations were minimal. Our data suggest that all three species are good sources of antioxidants, and the heavy metal concentrations are below the upper limits set by the French recommendation and the EU Commission Regulation on contaminants in foodstuffs. A health risk assessment indicated that consumption of these seaweed species poses a low risk for humans with regard to heavy metals. However, an EU-wide regulation on maximal concentration of heavy metals in seaweeds should be established.publishedVersio

Role of size and composition of traffic and agricultural aerosols in the molecular responses triggered in airway epithelial cells

International audienc

Study of the submicronic particle pollution at a French urban site

The French community involved in air quality monitoring early got interested in the measurement of submicronic particles. Since 2003, INERIS has carried out monitoring campaigns once or twice a year in an urban site located near Paris, enabling the constitution of a large hourly database. Besides particle number concentrations and size distribution measured by SMPS/APS, other variables have been introduced into the database: mass concentrations of several pollutants; traffic emissions computed by AIRPARIF from real-time traffic counts; measured or modelled meteorological variables. Since 2009, particle number concentration data have also been provided by 3031 measurements. An exploratory study of the data collected from 2003 to 2007, which focused on particles with diameter in the 10 nm to 500 nm range, was performed in 2008-2009 and presented at the EFCA 2009 symposium. The aim was to gain better insight into the number concentration and size of submicronic particles and better understanding of the sources and processes at stake in an urban environment. A synthetic scheme explaining the daily evolution of submicronic particle concentrations as a function of emissions and meteorology was established. More recently, following the EFCA symposium, investigations have been carried out thanks to additional monitoring campaigns and the enlargement of the summer database, previously limited to three weeks of measurements. Particle number concentrations over those three weeks appeared to be significantly higher than those measured in winter and revealed enhanced photochemical activity. Two recent campaigns of 7 to 11 weeks provided values inferior to winter concentrations, which is in better agreement with data from other European studies. The specificity of the summer season is still confirmed, with a photochemical signal in the early afternoon preceding the ozone peak. In addition to those results, a feedback about 3031 monitoring is presented