A preliminary study on the treatment of human blood soiled stubs, in presence of GSR particles.

In the investigation of gunshot deaths, Bloodstains Pattern Analysis (BPA) and, in particular, backspatter patterns found on the body of the suspect/victim and on the surfaces close to the entrance wound of the bullet can provide investigators with important indications on the dynamics of the events. Backspatter patterns have, however, morphological characteristics common to other bloodstains of different origin, so, in order to positively identify them, a possible solution is represented by their sampling, using an aluminum stub for electron microscopy, for the detection of gunshot residues (GSR) present. The latter, however, if present below the small blood crusts, could be difficult to detect during analysis by Scanning Electron Microscopy/Energy Dispersive X-ray microanalysis (SEM/EDX). In this preliminary study we propose the treatment of the stub surface with a solution based on sodium hypochlorite and calcium chloride, in order to remove/reduce the blood crusts present on the stub surface.

Enzyme Immunoassay for Measuring Aflatoxin B1 in Legal Cannabis.

The diffusion of the legalization of cannabis for recreational, medicinal and nutraceutical uses requires the development of adequate analytical methods to assure the safety and security of such products. In particular, aflatoxins are considered to pose a major risk for the health of cannabis consumers. Among analytical methods that allows for adequate monitoring of food safety, immunoassays play a major role thanks to their cost-effectiveness, high-throughput capacity, simplicity and limited requirement for equipment and skilled operators. Therefore, a rapid and sensitive enzyme immunoassay has been adapted to measure the most hazardous aflatoxin B1 in cannabis products. The assay was acceptably accurate (recovery rate: 78-136%), reproducible (intra- and inter-assay means coefficients of variation 11.8% and 13.8%, respectively), and sensitive (limit of detection and range of quantification: 0.35 ng mL-1 and 0.4-2 ng mL-1, respectively corresponding to 7 ng g-1 and 8-40 ng g-1 ng g-1 in the plant) and provided results which agreed with a HPLC-MS/MS method for the direct analysis of aflatoxin B1 in cannabis inflorescence and leaves. In addition, the carcinogenic aflatoxin B1 was detected in 50% of the cannabis products analyzed (14 samples collected from small retails) at levels exceeding those admitted by the European Union in commodities intended for direct human consumption, thus envisaging the need for effective surveillance of aflatoxin contamination in legal cannabis.

Chromium, nickel, and cobalt in cosmetic matrices: an integrated bioanalytical characterization through total content, bioaccessibility, and Cr(III)/Cr(VI) speciation.

The presence of certain metals naturally contained inside raw materials (e.g., pigments) used to produce cosmetics for make-up may represent a serious concern for the final quality and safety of the product. The knowledge of the total concentration of metals is not sufficient to predict their reactivity and their toxicological profile. For these reasons, we set up a comprehensive approach to characterize the content of Co, Cr, and Ni in two raw materials for cosmetic production, a black iron oxide and a pearly pigment, and in a finished product, pearly powder eye shadow. Namely, besides the total metal concentrations, the speciation of chromium and the bioaccessibility of the three metals were assessed. Since no standard method is so far available for hexavalent chromium extraction from cosmetic samples, three approaches were compared (EPA 3060A method, IRSA 16 method, and a Na3PO4 extraction). Results show that Na3PO4 extraction is the most selective one. Cr(VI) was undetectable in black iron oxide and present at very low concentrations (about 0.3 mg/kg) in pearly pigment and in the pearly powder eye shadow samples. The extracted Cr(VI) concentrations are not related to the total Cr content in the samples. Bioaccessibility studies were performed by in vitro extractions with synthetic lacrimal fluids and sweat. Despite the wide range of metal concentrations in the samples, the amounts of bioaccessible elements were undetectable or very low (less than 0.4 mg/kg), thus suggesting that metals in the three samples are present in inert forms. Graphical abstract The possible leaching of metals from cosmetics to biological fluids. Spectroscopic and chromatographic techniques provide complementary information for an integrated bioanalytical approach to risk characterization.