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Industrialization and advancements in agriculture are increasingly the cause of environmental concerns and need to be addressed. This study was carried out at four sampling sites, viz. Manimuthar (site 1), Tirunelveli (site 2), Srivaikuntam (site 3), and Authoor (site 4), along the Thamirabarani river. The heavy metal concentration in fish and sediments were ranged from 0.001 to 9.505 mg kg-1 and 0.294 to 106.25 mg kg-1. The lifetime cancer risk (LCR) values for children and adults were found to be above the acceptable threshold value (ATV) and children were found to be more susceptible to health risks. For all sites except site 4, the LCR of toxic metals except Cd were within the ATV (10-6-10-4); the value of Cd was above the ATV, and poses a high cancer risk to the downstream inhabitants. This study advises routine heavy metal monitoring on aquatic organisms along these sites to implement regulatory standards.Laboratories from 14 countries (with different levels of expertise in radionuclide measurements and 210Pb dating) participated in an interlaboratory comparison exercise (ILC) related to the application of 210Pb sediment dating technique within the framework of the IAEA Coordinated Research Project. The laboratories were provided with samples from a composite sediment core and were required to provide massic activities of several radionuclides and an age versus depth model from the obtained results, using the most suitable 210Pb dating model. Massic concentrations of Zn and Cu were also determined to be used for chronology validation. The ILC results indicated good analytical performances while the dating results didn’t demonstrate the same degree of competence in part due to the different experience in dating of the participant laboratories. The ILC exercise enabled evaluation of the difficulties faced by laboratories implementing 210Pb dating methods and identified some limitations in providing reliable chronologies.While globally distributed throughout the world’s ecosystems, there is little baseline information on persistent organic pollutants (POPs) in marine environments in Australia and, more broadly, the Southern Hemisphere. To fill this knowledge gap, we collected baseline information on POPs in migratory short-tailed shearwaters (Ardenna tenuirostris) from Fisher Island, Tasmania, and resident little penguins (Eudyptula minor) from Phillip Island, Victoria. Levels of polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs) and brominated flame retardants (BFRs) were determined from blood samples, with total contamination ranging 7.6-47.7 ng/g ww for short-tailed shearwaters and 0.12-46.9 ng/g ww for little penguins. In both species contamination followed the same pattern where PCBs>OCPs>BFRs. BFR levels included the presence of the novel flame retardant hexabromobenzene (HBB). These novel results of POPs in seabirds in southeast Australia provide important information on the local (penguins) and global (shearwaters) distribution of POPs in the marine environment.Batch experiments were conducted to study the migration behavior of arsenic (As) and iron (bivalent, trivalent, and total Fe) of the presence of the low molecular weight organic acids (LMWOAs) citric acid, malic acid, and oxalic acid in As-enriched mangrove sediments. The results for supernatant As/Fe species were significant according to each LMWOA treatment. Significant non-linear correlations were found among As level, pH, and acid dose based on our predictive model. The capacity of LMWOAs to mobilize As/Fe species followed the order of citric acid > malic acid/oxalic acid. selleck kinase inhibitor The supernatant As correlated positively with the LMWOAs dose and negatively correlated with the pH. As migration was affected by acid strength, the number of carboxyl groups, the pH and levels of Fe compounds in the sediments. The results indicate that LMWOAs can potentially attenuate As contamination from mangrove sediment, allowing for a better understanding of As/Fe behavior in the rhizosphere.Tributyltin (TBT) was a commonly used biocide in anti-fouling paints for marine vessels, however, it had negative impacts on non-target species, including causing imposex in dogwhelks (Nucella lapillus). Since the 1980s, legislation has been introduced to curtail its usage, culminating in a ban by the International Maritime Organisation (IMO) in 2008. In 2004 a national imposex monitoring network was established in Northern Ireland to determine the level and extent of TBT pollution. The level of imposex in N. lapillus was assessed according to the degree of male sexual development in the female using three measures percentage of imposex-affected females (%I), the relative penis size index (RPSI), and the vas deferens sequence index (VDSI). All sites showed improvement since the initial survey with a reduction in imposex and an improvement in ecological quality under the classification of the Convention for the Protection of the Marine Environment of the North-East Atlantic (OSPAR).Although the memory- improving effect of crocin has been suggested by previous evidences, the association between this effect and hippocampal acetylcholine (Ach) level and apoptosis is not well investigated. This study aimed to determine the protective effects of crocin on memory, hippocampal Ach level, and apoptosis in a rat model of cerebral ischemia. Male Wistar rats were divided into sham group received saline, and other 3 groups underwent 4-vessel occlusion brain ischemia (4VOI), received oral administration of either saline or crocin in doses of 30 mg/day and 60 mg/day for 7 days. Outcomes were memory, determined by radial eight-arm maze (RAM) task and Morris water maze (MWM) test, Ach release in the dorsal hippocampus (evaluated by microdialysis-HPLC) and apoptosis (investigated by TUNEL assay). 4VOI impaired memory reduced dorsal hippocampus Ach level, and induced apoptosis. Crocin, significantly improved the memory (F = 343.20; P less then 0.001 for RAM error choices and F = 182.5; P less then 0.0001 for MWM), increased Ach level (F = 115.1; P less then 0.001) and prevented hippocampal neuronal apoptosis (W = 183.50; P less then 0.001) as compared statistically by ANOVA test. Crocin can be suggested as a promising therapy for ischemic cerebrovascular accidents by its memory preserving, Ach-increasing, and neuroprotective effects.