8 research outputs found
Comprehensive framework for human health risk assessment of nanopesticides
Nanopesticides are not only in an advanced state of research and development but have started to appear on the market. Industry and regulatory agencies need a consolidated and comprehensive framework and guidance for human health risk assessments. In this perspective we develop such a comprehensive framework by exploring two case studies from relevant product types: an active ingredient delivered with a nanocarrier system, and a nanoparticle as an active ingredient. For a nanocarrier system, three entities are tracked during the assessment: the nanocarrier–active ingredient complex, the empty nanocarrier remaining after the complete release of the active ingredient, and the released active ingredient. For the nanoparticle of pure active ingredient, only two entities are relevant: the nanoparticle and the released ions. We suggest important adaptations of the existing pesticide framework to determine the relevant nanopesticide entities and their concentrations for toxicity testing. Depending on the nature of the nanopesticides, additional data requirements, such as those pertaining to durability in biological media and potential for crossing biological barriers, have also been identified. Overall, our framework suggests a tiered approach for human health risk assessment, which is applicable for a range of nanopesticide products to support regulators and industry in making informed decisions on nanopesticide submissions. Brief summaries of suitable methods including references to existing standards (if available) have been included together with an analysis of current knowledge gaps. Our study is an important step towards a harmonized approach accepted by regulatory agencies for assessing nanopesticides
Identification of Tsetse (Glossina spp.) using matrix-assisted laser desorption/ionisation time of flight mass spectrometry
Glossina (G.) spp. (Diptera: Glossinidae), known as tsetse flies, are vectors
of African trypanosomes that cause sleeping sickness in humans and nagana in
domestic livestock. Knowledge on tsetse distribution and accurate species
identification help identify potential vector intervention sites.
Morphological species identification of tsetse is challenging and sometimes
not accurate. The matrix-assisted laser desorption/ionisation time of flight
mass spectrometry (MALDI TOF MS) technique, already standardised for microbial
identification, could become a standard method for tsetse fly diagnostics.
Therefore, a unique spectra reference database was created for five lab-reared
species of riverine-, savannah- and forest- type tsetse flies and incorporated
with the commercial Biotyper 3.0 database. The standard formic
acid/acetonitrile extraction of male and female whole insects and their body
parts (head, thorax, abdomen, wings and legs) was used to obtain the flies'
proteins. The computed composite correlation index and cluster analysis
revealed the suitability of any tsetse body part for a rapid taxonomical
identification. Phyloproteomic analysis revealed that the peak patterns of G.
brevipalpis differed greatly from the other tsetse. This outcome was
comparable to previous theories that they might be considered as a sister
group to other tsetse spp. Freshly extracted samples were found to be matched
at the species level. However, sex differentiation proved to be less reliable.
Similarly processed samples of the common house fly Musca domestica (Diptera:
Muscidae; strain: Lei) did not yield any match with the tsetse reference
database. The inclusion of additional strains of morphologically defined wild
caught flies of known origin and the availability of large-scale mass
spectrometry data could facilitate rapid tsetse species identification in the
futur
Robust trace analysis of polar (C2-C8) perfluorinated carboxylic acids by liquid chromatography-tandem mass spectrometry: method development and application to surface water, groundwater and drinking water
Identification of Tsetse (Glossina spp.) Using Matrix-Assisted Laser Desorption/Ionisation Time of Flight Mass Spectrometry
Unlocking new alleles for leaf rust resistance in the Vavilov wheat collection
Thirteen potentially new leaf rust resistance loci were identified in a Vavilov wheat diversity panel. We demonstrated the potential of allele stacking to strengthen resistance against this important pathogen. Leaf rust (LR) caused by Puccinia triticina is an important disease of wheat (Triticum aestivum L.), and the deployment of genetically resistant cultivars is the most viable strategy to minimise yield losses. In this study, we evaluated a diversity panel of 295 bread wheat accessions from the N. I. Vavilov Institute of Plant Genetic Resources (St Petersburg, Russia) for LR resistance and performed genome-wide association studies (GWAS) using 10,748 polymorphic DArT-seq markers. The diversity panel was evaluated at seedling and adult plant growth stages using three P. triticina pathotypes prevalent in Australia. GWAS was applied to 11 phenotypic data sets which identified a total of 52 significant marker-trait associations representing 31 quantitative trait loci (QTL). Among them, 29 QTL were associated with adult plant resistance (APR). Of the 31 QTL, 13 were considered potentially new loci, whereas 4 co-located with previously catalogued Lr genes and 14 aligned to regions reported in other GWAS and genomic prediction studies. One seedling LR resistance QTL located on chromosome 3A showed pronounced levels of linkage disequilibrium among markers (r (2)\ua0=\ua00.7), suggested a high allelic fixation. Subsequent haplotype analysis for this region found seven haplotype variants, of which two were strongly associated with LR resistance at seedling stage. Similarly, analysis of an APR QTL on chromosome 7B revealed 22 variants, of which 4 were associated with resistance at\ua0the adult plant stage. Furthermore, most of the tested lines in the diversity panel carried 10 or more combined resistance-associated marker alleles, highlighting the potential of allele stacking for long-lasting resistance