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Polychlorinated biphenyls (PCBs) are one of the most widely studied group of persistent organic pollutants (POPs). There are 209 different PCBs, however not all 209 can currently be individually quantified in one analytical run. This means that a subset of PCBs congeners are often determined and reported. Some of the most commonly reported subsets are the 7 indicator PCBs (28, 52, 101, 118, 138, 153 and 180) and the WHO 12 PCBs (77, 81, 105, 114, 118, 123, 126, 156, 157, 167, 169 and 189). The WHO 12 congeners are co-planar 'dioxin like' PCBs that are effective for establishing health risks. The 7 indicator PCBs were selected as some of the most common PCBs across the compositional range of the most common technical mixtures (such as Aroclors), and are used to give an indication of the total PCB concentrations. These groups of indicator PCBs were established several decades ago. However, in the environment commercial mixtures are subject to weathering and fractionation processes, and additional sources of non-Aroclor PCBs are also becoming more important. In this manuscript we use existing large scale comprehensive congener specific datasets to evaluate the effectiveness of indicator PCBs to predict total concentrations and establish if they are still fit for purpose. The results indicate that while these traditional indicators are a useful tool to estimate total concentrations in humans with background exposure there are many instances where they are not fit for purpose and can lead to significant under predictions in total PCB concentrations in environmental matrices., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The aim of this study was to formulate, characterise and evaluate the activity of amodiaquine microparticles against Leishmania donovani. Microparticles were formulated by encapsulating the drug in bovine serum albumin using the spray-dryer method. The microparticles were evaluated for size, zeta potential, drug content, encapsulation efficiency and in vitro release profile. The size range of the microparticles formulated was between 1.9 and 10 μm with an average zeta potential of -25.5 mV. Of the expected 20% drug loading, an average of 18.27% was obtained giving an encapsulation efficiency of 91.35%. Pharmacokinetic profile of amodiaquine improved with microencapsulation of the drug with C max , AUC 0→48 and t 1//2 all significantly higher than amodiaquine solution. Amodiaquine microparticles showed an overall higher bioavailability and hence were more effective in eliminating intra-tissue parasites than the drug solution. It would therefore be expected that the formulated microparticles will be more effective in treating visceral leishmaniasis.