Development of an in vitro method to estimate lung bioaccessibility of metals from atmospheric particles

The research presented here was initiated to improve the current knowledge on easily released metals from atmospheric particles. The objectives of this paper were to develop an in vitro method to estimate lung bioaccessibility and to provide quantitative data on metals bioaccessibility. A large set of metals has been investigated (Ba, Cd, Ce, Co, Cu, La, Mn, Mo, Ni, Pb, Rb, Sb and Zn) using two distinct fluids (water and Gamble solution) on four reference materials representing different types of particle sources. Through this study, different parameters such as extraction-time, composition of the leaching solution and solid-to-liquid (S/L) ratios were investigated. The findings obtained for four SRMs suggest that the bioaccessibility is maximized after a 24 h extraction for a range of S/L ratios varying from 1/500 to 1/50,000. We clearly demonstrate that the higher bioaccessibility of metals is obtained with the Gamble solution. Moreover, our results imply that bioaccessibility is speciation and element dependent with percentages varying from 3.3% for Pb to 92.5% for Zn. An estimation of uncertainties of 11% to 30% was obtained for metals bioaccessibility in the four reference materials. In addition, the extraction procedure was validated by performing a mass balance on both soluble and insoluble fractions. This developed method may be used to evaluate the pulmonary bioaccessibility of trace elements present in the atmospheric particles without major artefacts.     

A large scale survey of trace metal levels in coastal waters of the Western Mediterranean basin using caged mussels (Mytilus galloprovincialis)

A large scale study of trace metal contamination (Hg, Cd, Pb and Ni) by means of caged mussels Mytilus galloprovincialis was undertaken along the coastal waters of the Western Mediterranean Sea within the context of the MYTILOS project. Individual mussels from an homogeneous population (shell size 50 ± 5 mm) obtained from an aquaculture farm were consecutively caged and deployed at 123 sites located in the Alborán, North-Western, South-Western and Tyrrhenian sub-basins for 12 weeks (April-July) in 2004, 2005 and 2006. After cage recoveries, both the metal content in the whole mussel tissue and the allometric parameters were measured. Statistical analysis of the datasets showed significant differences in concentrations between sub-basins for some metals and mussel condition index (CI). Linear regression models coupled to the CI were revisited for the data adjustment of certain trace metals (Hg, Cd and Ni), and four level categories were statistically derived to facilitate interregional comparison. Seawater masses surrounding coastal areas impacted by run-off from land mineralised coasts and industrial activities displayed the highest concentration ranges (Hg: 0.15-0.31 mg kg(-1) dw; Cd: 1.97-2.11; Ni: 2.18-3.20 and Pb: 3.1-3.8), although the levels obtained in most of the sites fitted within moderate or low categories, and they could be considered as baseline concentrations. However, few sites considered little-influenced by human activities, at present, showed high concentrations of Cd, Ni and Pb, which constitute new areas of concern. Overall, the use of active biomonitoring (ABM) approach allowed to investigate trace metal contamination in order to support policy makers in establishing regional strategies (particularly, with regard to the European Marine Strategy Directive).     

Photochemical persistence of sulfa drugs in aqueous medium: kinetic study and mathematical simulations

Environmental Science and Pollution Research - This study aimed at investigating the photochemical behavior of sulfa drugs containing five and six-membered heterocyclic substituents...     

Multi-criteria assessment of the viability of valorising vegetable by-products from the distribution as secondary raw material for animal feed

Environmental Science and Pollution Research - Approximately 33% of food produced around the world is wasted. In the distribution sector, erroneous orders or demand predictions result in products...     

Genotoxic and melanic alterations in Lithobates catesbeianus (anura) tadpoles exposed to fipronil insecticide

Environmental Science and Pollution Research - The aim of this study was to evaluate the genotoxic and morphological systemic effects of both an acute and a chronic exposure of bullfrog tadpoles to...     

Partial compensation of the sublethal effect of deltamethrin on the sex pheromonal communication of Trichogramma brassicae

Pyrethroid insecticides are widely used and lead to a sizable environmental pollution that could interfere with the population biology of insects. Trichogramma is a beneficial insect used in biological control and which natural populations contribute to the control of Lepidopterus pests. In this work, we determined the effect of a sublethal dose of deltamethrin on the sex pheromonal communication of Trichogramma. The dose used (LD 0.1) induces no detectable mortality (the theoretical mortality is only one insect over 1000) and can be a good representation of contamination by this insecticide from environmental pollution. The insecticide was shown to have opposite effects on the sex pheromonal communication of Trichogramma, depending on which sex was exposed (Delpuech, J.M., Legallet, B., Terrier, O., Fouillet, P., 1999. Chemosphere 38, 729–739). We show that, when both sexes are simultaneously exposed to the insecticide, this effect is only partially neutralized. The mean response of treated males responding to the sex pheromone from treated females is not significantly different from that of controls, but the kinetics of their response is not the same. When both sexes are treated, the response of males to the sex pheromone is lower at the beginning but their response does not decrease during time contrary to controls and becomes finally higher than that of controls. Therefore, the sublethal effect of deltamethrin in the field can be either advantageous or disadvantageous depending on the difficulty in finding females and their scarcity.     

Changing Ecosystem Service Values Following Technological Change

Research on ecosystem services has focused mostly on natural areas or remote places, with less attention given to urban ecosystem services and their relationship with technological change. However, recent work by urban ecologists and urban designers has more closely examined and appreciated the opportunities associated with integrating natural and built infrastructures. Nevertheless, a perception remains in the literature on ecosystem services that technology may easily and irreversibly substitute for services previously obtained from ecosystems, especially when the superiority of the engineered system motivated replacement in the first place. We emphasize that the expected tradeoff between natural and manufactured capital is false. Rather, as argued in other contexts, the adoption of new technologies is complementary to ecosystem management. The complementarity of ecosystem services and technology is illustrated with a case study in Barcelona, Spain where the installation of sophisticated water treatment technology increased the value of the ecosystem services found there. Interestingly, the complementarity between natural and built infrastructures may remain even for the very ecosystems that are affected by the technological change. This finding suggests that we can expect the value of ecosystem services to co-evolve with new technologies. Technological innovation can generate new opportunities to harness value from ecosystems, and the engineered structures found in cities may generate more reliance on ecosystem processes, not less.     

Optimal Experimental Conditions for Improving the Yield of Poly(limonene) from Photoinduced Polymerization

Journal of Polymers and the Environment - Limonene represents a possible candidate for the synthesis of polymers from renewable sources. However, because of some structural characteristics, the...