TOPICAL REVIEW: Microfluidics for flow cytometric analysis of cells and particles

This review describes recent developments in microfabricated flow cytometers and related microfluidic devices that can detect, analyze, and sort cells or particles. The high-speed analytical capabilities of flow cytometry depend on the cooperative use of microfluidics, optics and electronics. Along with the improvement of other components, replacement of conventional glass capillary-based fluidics with microfluidic sample handling systems operating in microfabricated structures enables volume- and power-efficient, inexpensive and flexible analysis of particulate samples. In this review, we present various efforts that take advantage of novel microscale flow phenomena and microfabrication techniques to build microfluidic cell analysis systems.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/49182/2/pm5_3_r02.pd

Est-il plus sur de faire pousser ses propres légumes? Utilisation des potagers dans les sites industriels pollués

International audienceFrom September 2016 till November 2016, the Institut Ecocitoyen pour la Connaissance des Pollutions (IECP) performed conducted from september 2016 to november 2016 a biomonitoring study survey in the industrial city town of Fos-sur-Mer (INDEX programm). During this studythe this survey, samples of urine and blood were analyzed for tested for more than 50 pollutants onto in 79 citizens inhabitants of Fos-sur-Mer and 59 citizens of a control area (Saint-Martin-de-Crau) localized 20 km far away from industries. We collected iInformation on occupation, lifestyle habits, food intake and, health were collected by questionnaires. An interdisciplinary project named ECOLEX was created launched to add a sociological dimension to complement INDEX with sociological data too. The aim was to investigate the volunteers' environmental perception of the volunteers from in both areas through a second questionnaire based on population feeling understanding of risk and attitudes towards about the impact of industrial pollution on their their environment and, health. Attention was also paid to , life habits etcdomestic and environmental practices. We wanted to put to trial some hypothesis elaborated from the literature which insist on the corrosive effects of pollution on the social fabric (Erikson 1994; Freudenburg 1997; Gramaglia 2015) and the development of subcultures of distress (Couch, Mercuri 2007). Our first results show that the majority of the inhabitants of the Fos-sur-Mer industrial area consider their town to be as polluted or even more polluted than a big city, when 91 % of people in the population from the controlSaint-Martin de Crau area considers their city as less polluted than a « big city » against 17.5 % only in the industrial areadisagree with this opinion. However, they are more thanabout 60 % ofin the control area population admitted to beto be at least a bit worry worried about the potential effects of industrial atmospheric pollution on their environment and health on their environment. This number is even higher in the exposed area where none stated that he/she didn't feel potentially at risk. Crossing informations given by both questionnaires allow us to explore the relation between pollution perception and some individual behaviour such as gardening. We will focus in tThis presentation will focus on the volunteers foovegetable growing and food habits as we noticed that a similar number of the people we pooled had a piece of land which they gardenedd habits and their relation to gardening. In both area, the percentage of people owning a garden is similar (respectively 86 and 88% in Fos and St Martin, including both owners and tenants). But However, in the exposed area directly exposed to industrial emissions, they are were 10% less to do sothan in control area to cultivate vegetables in the garden. Curiously, in the exposed areaFos-sur-Mer, the volunteers which who declared to be moderately or very worry worried about pollution effects on their environment and health, cultivate were more likely to cultivate more their garden than the fewer who felt one not or fewless concerned about it. They are were yet more sensible informed and sensitive to about the organic culture farming methods as they aremore than 60 34 % of them said they had already consumedto never consumed organic products (whether against 52less than 50% for of the less concerned confessed so). Our communication will give us the opportunity to explore the relation between perception of risk, attitudes, domestic and environmental practices and habits in different contexts where industrial pollution is more or less a worry. Relying on ethnographic material we collected beforehand, we will question specific changes in gardening habits. Why are inhabitants with a higher concern about pollution in Fos-sur-Mer so enclined to home grow their vegetable (when industrial emission can alter the quality of locally produced food)? How is environmental awareness constructed regarding local and broader issues? Does it influence the choice to favour organic farming methods (or buy organic food at their grocer's)? How do the exposed area population and the control area one relate to pesticides and make sense of the risks they convey (in relation to other chemical risks)? Do risk cultures exist and can they be articulated (Peretti-Wattel 2005)? Most of the time, studies about industrial (Gibout, Zwarterook 2013) and agricultural pollution (Barrault 2009) are disconnected. We intend to cross-examine them and see how they might influence individual and collective behaviours in Fos-sur-Mer and Saint-Martin de Crau, and may induce adaptative strategies to resist the alteration of living conditions there (Murphy 2016)

Foliar uptake and metal(loid) bioaccessibility in vegetables exposed to particulate matter

At the global scale, high concentrations of particulate matter (PM) enriched with metal(loid)s are currently observed in the atmosphere of urban areas. Foliar lead uptake was demonstrated for vegetables exposed to airborne PM. Our main objective here was to highlight the health risk associated with the consumption of vegetables exposed to foliar deposits of PM enriched with the various metal(loid)s frequently observed in the atmosphere of urban areas (Cd, Sb, Zn and Pb). Leaves of mature cabbage and spinach were exposed to manufactured mono-metallic oxide particles (CdO, Sb2O3 and ZnO) or to complex process PM mainly enriched with lead. Total and bioaccessible metal(loid) concentrations were then measured for polluted vegetables and the various PM used as sources. Finally, scanning electronic microscopy coupled with energy dispersive X-ray microanalysis was used to study PM–phyllosphere interactions. High quantities of Cd, Sb, Zn and Pb were taken up by the plant leaves. These levels depended on both the plant species and nature of the PM, highlighting the interest of acquiring data for different plants and sources of exposure in order to better identify and manage health risks. A maximum of 2 % of the leaf surfaces were covered with the PM. However, particles appeared to be enriched in stomatal openings, with up to 12 % of their area occupied. Metal(loid) bioaccessibility was significantly higher for vegetables compared to PM sources, certainly due to chemical speciation changes. Taken together, these results confirm the importance of taking atmospheric PM into account when assessing the health risks associated with ingestion of vegetables grown in urban vegetable crops or kitchen gardens

Influence of source distribution and geochemical composition of aerosols on children exposure in the large polymetallic mining region of the Bolivian Altiplano

The Bolivian Altiplano (Highlands) region is subject to intense mining, tailing and smelting activities since centuries because of the presence of large and unique polymetallic ore deposits (Ag, Au, Cu, Pb, Sn, Sb, Zn). A large scale PM(10), Pm(2.5) aerosol monitoring survey was conducted during the dry season in one of the largest mining cities of this region (Oruro, 200,000 inhabitants). Aerosol fractions, source distribution and transport were investigated for 23 elements at approximately 1 km(2) scale resolution, and compared to children exposure data obtained within the same geographical space. As, Cd, Pb, Sb, W and Zn in aerosols are present at relatively high concentrations when compared to studies from other mining regions. Arsenic exceeds the European council PM(10) guide value (6 ng/m(3)) for 90% of the samples, topping 200 ng/m(3). Ag, As, Cd, Cu, Pb and Sb are present at significantly higher levels in the district located in the vicinity of the smelter zone. At the city level, principal component analysis combined with the mapping of factor scores allowed the identification and deconvolution of four individual sources: i) a natural magmatic source (Co, Cs, Fe, K. Mn, Na, Rb and U) originating from soil dust, resuspended by the traffic activity; ii) a natural sedimentary source (Mg, Ca, Sr, Ba and Th) resulting from the suspension of evaporative salt deposits located South; iii) an anthropogenic source specifically enriched in mined elements (As, Cd, Cu, Pb, Sb and Zn) mainly in the smelting district of the city; and iv) a Ni-Cr source homogenously distributed between the different city districts. Enrichment factors for As, Cd and Sb clearly show the impact of smelting activities, particularly in the finest PM(2.5) fraction. Comparison to children's hair metal contents collected in five schools from different districts shows a direct exposure to smelting activity fingerprinted by a unique trace elements pattern (Ag, As, Cu, Pb, Sb)

Synergistic effects of mining and urban effluents on the level and distribution of methylmercury in a shallow aquatic ecosystem of the Bolivian Altiplano

International audienceLake Uru Uru (3686 m a.s.l.) located in the Bolivian Altiplano region receives both mining effluents and urban wastewater discharges originating from the surrounding local cities which are under rapid development. We followed the spatiotemporal distribution of different mercury (Hg) compounds and other metal(oid)s (e.g.{,} Fe{,} Mn{,} Sb{,} Ti and W) in both water and sediments during the wet and dry seasons along a north-south transect of this shallow lake system. Along the transect{,} the highest Hg and metal(oid) concentrations in both water and sediments were found downstream of the confluences with mining effluents. Although a dilution effect was found for major elements during the wet season{,} mean Hg and metal(oid) concentrations did not significantly differ from the dry season due to the increase in acid mine drainage (AMD) inputs into the lake from upstream mining areas. In particular{,} high filtered (<0.45 [small mu ]m) mono-methylmercury (MMHg) concentrations (0.69 +/- 0.47 ng L-1) were measured in surface water representing 49 +/- 11% of the total filtered Hg concentrations (THgF) for both seasons. Enhanced MMHg lability in relation with the water alkalinity{,} coupled with abundant organic ligands and colloids (especially for downstream mining effluents){,} are likely factors favoring Hg methylation and MMHg preservation while inhibiting MMHg photodegradation. Lake sediments were identified as the major source of MMHg for the shallow water column. During the dry season{,} diffusive fluxes were estimated to be 227 ng m-2 d-1 for MMHg. This contribution was found to be negligible during the wet season due to a probable shift of the redox front downwards in the sediments. During the wet season{,} the results obtained suggest that various sources such as mining effluents and benthic or macrophytic biofilms significantly contribute to MMHg inputs in the water column. This work demonstrates the seasonally dependent synergistic effect of AMD and urban effluents on the shallow{,} productive and evaporative high altitude lake ecosystems which promotes the formation of natural organometallic toxins such as MMHg in the water column

Transplantation of epiphytic bioaccumulators (Tillandsia capillaris) for high spatial resolution biomonitoring of trace elements and point sources deconvolution in a complex mining/smelting urban context

Monitoring atmospheric trace elements (TE) levels and tracing their source origin is essential for exposure assessment and human health studies. Epiphytic Tillandsia capillaris plants were used as bio-accumulator of TE in a complex polymetallic mining/smelting urban context (Oruro, Bolivia). Specimens collected from a pristine reference site were transplanted at a high spatial resolution (similar to 1 sample/km(2)) throughout the urban area. About twenty-seven elements were measured after a 4-month exposure, also providing new information values for reference material BCR482. Statistical power analysis for this biomonitoring mapping approach against classical aerosols surveys performed on the same site showed the better aptitude of T. Capillaris to detect geographical trend, and to deconvolute multiple contamination sources using geostatistical principal component analysis. Transplanted specimens in the vicinity of the mining and smelting areas were characterized by extreme TE accumulation (Sn > Ag > Sb > Pb > Cd > As > W > Cu > Zn). Three contamination sources were identified: mining (Ag, Pb, Sb), smelting (As, Sn) and road traffic (Zn) emissions, confirming results of previous aerosol survey