Neurotoxic effect and metabolic responses induced by a mixture of six pesticides on the earthworm Aporrectodea caliginosa nocturna

The effects of a mixture of insecticides and/or fungicides at different environmental concentrations were investigated on a Aporrectodea caliginosa nocturna population. This laboratory experiment was carried out in order to reproduce Gaillac (France) vineyard conditions. Neurotoxicity (cholinesterase), metabolisation (glutathione-S-transferase) and oxidative stress (catalase) enzymes were studied as biomarkers in earthworms after short-term exposure in terraria. The aim was to observe the global effects of pesticide exposure, as in a vineyard, rather than focus on each isolated biomarker variation, or on each compound's impact. ChE activity was inhibited after a few days of insecticide and/or fungicide exposure, indicative of a neurotoxic effect in earthworms. The significant increase in GST and CAT activities revealed the metabolisation of these products resulting in the production of reactive oxygen species. After a long period of exposure or high concentrations, earthworms were physiologically damaged: they could not cope with the high toxicity (cellular dysfunction, protein catabolism...). Chemical analysis showed that pesticide bioaccumulation in earthworm tissues, even in those exposed to the highest concentrations and for the longest periods, was very low (under LOD) or absent. However, the study of pesticide residues in terraria after 34 days in a climate chamber suggested that earthworms participate in soil pesticide breakdown.     

Green manure plants for remediation of soils polluted by metals and metalloids: Ecotoxicity and human bioavailability assessment

Borage, white mustard and phacelia, green manure plants currently used in agriculture to improve soil properties were cultivated for 10 wk on various polluted soils with metal(loid) concentrations representative of urban brownfields or polluted kitchen gardens. Metal(loid) bioavailability and ecotoxicity were measured in relation to soil characteristics before and after treatment. All the plants efficiently grow on the various polluted soils. But borage and mustard only are able to modify the soil characteristics and metal(loid) impact: soil respiration increased while ecotoxicity, bioaccessible lead and total metal(loid) quantities in soils can be decreased respectively by phytostabilization and phytoextraction mechanisms. These two plants could therefore be used for urban polluted soil refunctionalization. However, plant efficiency to improve soil quality strongly depends on soil characteristics.     

Kinetic study of phytotoxicity induced by foliar lead uptake for vegetables exposed to fine particles and implications for sustainable urban agriculture

At the global scale, foliar metal transfer occurs for consumed vegetables cultivated in numerous urban or industrial areas with a polluted atmosphere. However, the kinetics of metal uptake, translocation and involved phytotoxicity was never jointly studied with vegetables exposed to micronic and sub-micronic particles (PM). Different leafy vegetables (lettuces and cabbages) cultivated in RHIZOtest® devices were, therefore, exposed in a greenhouse for 5, 10 and 15 days to various PbO PM doses. The kinetics of transfer and phytotoxicity was assessed in relation to lead concentration and exposure duration. A significant Pb accumulation in leaves (up to 7392 mg/kg dry weight (DW) in lettuce) with translocation to roots was observed. Lead foliar exposure resulted in significant phytotoxicity, lipid composition change, a decrease of plant shoot growth (up to 68.2% in lettuce) and net photosynthesis (up to 58% in lettuce). The phytotoxicity results indicated plant adaptation to Pb and a higher sensitivity of lettuce in comparison with cabbage. Air quality needs, therefore, to be considered for the health and quality of vegetables grown in polluted areas, such as certain megacities (in China, Pakistan, Europe, etc.) and furthermore, to assess the health risks associated with their consumption.     

Influence of earthworm bioturbation on metals phytoavailability and human gastric bioaccessibility

Environmental Science and Pollution Research - At the global scale, urban agriculture is increasingly developing in cities due to demographic growth and sustainable food concerns. But, urban soils...     

Influence of soil ageing on bioavailability and ecotoxicity of lead carried by process waste metallic ultrafine particles

Ultrafine particulate matters enriched with metals are emitted into the atmosphere by industrial activities and can impact terrestrial and aquatic ecosystems. Thus, this study investigated the environmental effects of process particles from a lead-recycling facility after atmospheric deposition on soils and potential run-off to surface waters. The toxicity of lead-enriched PM for ecosystems was investigated on lettuce and bacteria by (i) germination tests, growth assays, lead transfer to plant tissues determination and (ii) Microtox analysis.The influence of ageing and soil properties on metal transfer and ecotoxicity was studied using three different soils and comparing various aged, spiked or historically long-term polluted soils. Finally, lead availability was assessed by 0.01 M CaCl₂ soil extraction.The results showed that process PM have a toxic effect on lettuce seedling growth and on Vibrio fischeri metabolism. Soil-PM interactions significantly influence PM ecotoxicity and bioavailability; the effect is complex and depends on the duration of ageing. Solubilisation or stabilisation processes with metal speciation changes could be involved. Finally, Microtox and phytotoxicity tests are sensitive and complementary tools for studying process PM ecotoxicity.     

Tetrasomy 12p—unusual presentation in CVS

CVS direct preparations usually achieve limited resolution and are better at detecting numerical rather than structural abnormalities. A CVS direct preparation analyzed using G-banding revealed a 47,XY,+G karyotype in 5 of 11 cells and was reported as mosaic for trisomy 21. Subsequent analysis of the CVS culture found only normal male cells. Amniocentesis revealed both normal male cells and cells with an extra F-group chromosome. Fluorescence in situ hybridization (FISH) identified this chromosome to be an isochromosome from the short arm of chromosome 12 [i(12)(p10)]. The amniocyte karyotype was reported as 47,XY,+i(12)(p10)[12]/46,XY[8].ish i(12)(p10)(wcp12+), which is associated with Pallister–Killian syndrome. Reexamination of the CVS direct preparation by FISH with a chromosome 12 centromere probe confirmed the karyotype of this tissue to be 47,XY,+mar[5]/46,XY[6].nuc ish 12cen(D12Z3 × 3)/12cen(D12Z3 × 2). Thus, multiple studies, including amniocentesis and fluorescence in situ hybridization, may be required to fully and accurately evaluate abnormalities detected by CVS. This case also indicates that mosaicism for supernumerary isochromosomes may have a complex origin. Copyright © 2003 John Wiley & Sons, Ltd.     

Trisomy 8 mosaicism in chorionic villus sampling: Case report and counselling issues

We report an unusual case involving chorionic villus sampling (CVS) and trisomy 8 mosaicism. CVS showed a normal direct preparation while the culture showed mosaicism for trisomy 8. Subsequent amniocentesis revealed only normal chromosomes. A peripheral blood culture after birth revealed low-level trisomy 8 mosaicism. The patient appeared phenotypically and developmentally normal at 30 months of age. We conclude that prenatal counselling for similar cases needs to include the rare but real possibility that chromosome mosaicism detected prenatally may be found postnatally with largely unknown consequences. Secondly, low-level chromosomal mosaicism may be more common than previously recognized. Thirdly, very low-level trisomy 8 mosaicism may be compatible with a normal phenotype but long-term follow-up is required. And lastly, the use of fetal blood sampling is questionable in these cases because the phenotype may not be accurately predicted. Further studies of such cases are needed to address these important and unanswered issues, including the potential implication of mosaicism on academic performance and cognitive functioning.     

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.