The effect of diazinon on blood glucose homeostasis: a systematic and meta-analysis study

Environmental Science and Pollution Research - Though evidence exists on the association between diazinon (DZN), an organophosphate pesticide, with hyperglycemia, contrasting reports also exist....     

Principles and perspectives

BACKGROUND, AIM AND SCOPE: With respect to the enormous increase of chemical production in the last decades and the tens of thousands of individual chemicals on the market, the permanent improvement of chemical management is a permanent target to achieve the goals of sustainable consumption and production set by the WSSD in Johannesburg 2002. MAIN FEATURES: Several approaches exist to describe sustainability of chemistry. However, commonly agreed criteria are still missing. There is no doubt that products of modern chemistry help to achieve important goals of sustainability and that significant improvements have occurred regarding direct releases from production sites, but several facts demonstrate that chemistry is far from being sustainable. Still too many chemicals exhibit hazardous characteristics and pose a risk to health and environment. Too many resources are needed to produce chemicals and finished products. RESULTS AND CONCLUSION: Therefore, a strategy for sustainability of chemistry should be developed which comprises the following main elements: 1. Sustainable chemicals: sustainable chemical management includes a regulatory framework which makes no difference between new and existing chemicals, contains efficient information flow through the supply chain which allows users to handle chemicals safely and offers an authorisation procedure and/or an efficient restriction procedure for substances of high concern. This regulatory scheme should promote the development of inherently safe chemicals. 2. Sustainable chemical production: Sustainable chemical production needs the development and implementation of emerging alternative techniques like selective catalysis, biotechnology in order to release less CO2 and less toxic by-products, to save energy and to achieve higher yields. Information exchange on best available techniques (BAT) and best environmental practices (BEP) may help to promote changes towards more sustainability. 3. Sustainable products: An integrated product policy which provides a framework for sustainable products promotes the development of products with a long-term use phase, low resource demand in production and use, low emission of hazardous substances and properties suitable for reuse and recycling. This may be promoted by eco-labelling, chemical leasing concepts and extended information measures to enhance the demand of consumers and various actors in the supply chain for sustainable products. RECOMMENDATION AND PERSPECTIVE: Important tools for the promotion of sustainable chemistry are the abolition of barriers for innovation in legislation and within the chemical industry, more transparency for all users of chemical products, a new focus on sustainability in education and research, and a new way of thinking in terms of sustainability.     

European starling nestling response to chlorpyrifos exposure in a corn agroecosystem

European starling (Sturnus vulgaris) nestlings were used as a surrogate to study the effect of chlorpyrifos application to a corn agroecosystem on songbird reproduction. Chlorpyrifos was applied in a T‐band at 1.3 kg AI/ha, and residues were measured in soil, earthworms, ground‐dwelling insects, and diet items collected from the crop of starling nestlings. Chlorpyrifos levels in soil peaked at 34.2 μg/g, 4 days post‐application, and dissipated to trace levels by 64 days post‐application. Concentrations of chlorpyrifos in earthworms and ground‐dwelling insects reached 0.9 and 0.7 ug/g, respectively. Starling nestling diet items included invertebrates from eight orders with chlorpyrifos concentrations ranging from trace levels to 10.6 μg/g in earthworms. Nestling brain and plasma cholinesterase (ChE) activity and body mass measurements were taken at 3, 8, and 13 days post‐hatch (DPH). Adult starling fecundity was also measured. Body mass differences between treatment and reference site nestlings at 3 and 13 DPH were not significant at α = 0.05. However, 8 DPH nestlings from the Treatment Site had a transient reduction in weight (p = 0.03) when compared with 8 DPH reference nestlings. There were no significant differences in brain or plasma ChE activities of 3, 8, or 13 DPH nestlings. Further, multiple measures of fecundity (i.e., clutch size, hatching percentage, and fledging percentage) indicated that chlorpyrifos application did not affect starling nestling survival to fledging, as the values from the Treatment and Reference Site were nearly identical. This screening‐level study suggests that although one age group of starling nestlings from the Treatment Site weighed less than their Reference Site counterparts, a single T‐band application of chlorpyrifos did not impair starling nesting success.     

Aqueous high‐temperature chemistry of arsenic‐containing compounds in water at 300°C

Arsenic compounds, and especially organo‐arsenic derivatives, are highly toxic and many have been manufactured as chemical warfare agents. This study was designed to provide background information relevant to the potential application of aquathermolysis techniques for the detoxification of such potent military warfare agents. Six arsenic‐containing compounds with structural features which mimic known agents were studied in neutral superheated water: 4‐aminophenylarsine oxide, 4‐arsanilic acid, 4‐nitrophenylarsonic acid, 5, 10‐dihydro‐10‐ethylphenarsazine, tetraphenylarsonium chloride hydrate, and (3‐cyanopropyl)dimethyl(2‐phenethyl)arsonium bromide. Most of these compounds were moderately susceptible to hydrolysis for 1h at 300°C. o‐ and p‐Aminosubsituted arsenic compounds were more reactive than compounds with an electron‐withdrawing group substituent. Aromatic C—As bonds were more resistant to cleavage than aliphatic C—As bonds.     

The role of social learning for soil conservation: the case of Amba Zuria land management,Ethiopia

Social learning plays key roles in sustainable natural resource management; however, studies on its role show mixed results. Even though most current studies highlight positive outcomes, there are also negative effects of social learning with respect to natural resource management. This paper explores the influence of social learning outcomes on the adoption of soil conservation practices in Amba Zuria, Ethiopia. Data were collected through semi-structured interviews, group discussions and in workshops. The interviews were transcribed and analysed with the qualitative data analysis software ATLAS.ti. In addition, a review of pertinent documents and literature complements the analysis. We found that social learning results in positive outcomes in interactions among the actors, broader understanding on soil conservation, trust and mutual understanding, and the creation of opportunities to apply both indigenous and scientific knowledge. These outcomes, in turn, foster the adoption of stone terraces to conserve soils. No such positive results were found for farmers who were not involved in the learning process and who did not adopt stone terraces. The non-adoption can partly be explained by their exclusion from sharing the positive outcomes of social learning. The study also shows limitations related to the short duration of the learning platforms, insufficient representation of women and irregular patterns of learning schedules. Hence, Ethiopian soil conservation strategies should put emphasis on social learning in order to strengthen the collective processes of soil conservation measures.     

Crediting uncertain ecosystem services in a market

The margin of safety (MOS) approach is an increasingly prevalent tool for ensuring the integrity of market-based programs for providing ecosystem services. Over-crediting is reduced by setting aside mean estimates of uncertain services in favor of a more conservative estimate. Like many environmental policy problems, ecosystem service markets involve the aggregation of uncertainty over multiple scales, e.g. from landowners to market intermediaries to the overall market. We examine how the MOS instrument affects, and is affected by, an ecosystem services market. We show that the common bottom-up approach of imposing risk preferences at a local, disaggregated level—held over from earlier development in the context of toxics and command and control-style health risk regulation—leads to several unintended consequences. Furthermore, discounting landowner services can actually increase their profits, conditional on the elasticity of credit demand. We illustrate theoretical insights with an empirical application to greenhouse gas offset crediting in agriculture.     

The role of Greenland sharks (Somniosus microcephalus) in an Arctic ecosystem: assessed via stable isotopes and fatty acids

The Greenland shark (Somniosus microcephalus) is the only shark species known to inhabit ice-covered seas in the North Atlantic, but remains a missing component in most studies of Arctic food webs. In the present study, stable isotopes (SIs) of nitrogen (δ¹⁵N) and carbon (δ¹³C) and fatty acids (FAs) were analyzed to identify the role of Greenland sharks (sampled during June 2008–2009) in Kongsfjorden, a productive fjord on the west coast of Svalbard, Norway (~79ºN, 12–13ºE). The Greenland shark fed at a high trophic position (4.8) based on δ¹⁵N values, and δ¹³C confirmed that most (70 %) of their carbon was derived from phytoplankton-based food chains, which is consistent with a heavy reliance on pelagic teleosts and seals. Greenland sharks from Kongsfjorden had fatty acid profiles in both muscle and plasma (e.g., low 20:1n-9, high 22:5n-3) that suggested a low portion of Greenland halibut (Reinhardtius hippoglossoides) and high proportion of gadoids and seals in their diet compared to Greenland sharks sampled in Cumberland Sound, Canada, during April 2008, which were previously shown to derive much of their energy from Greenland halibut. The high proportions of seal fatty acids in both slow- (muscle) and fast- (plasma) turnover tissues indicate that trophic interactions between Greenland sharks and seals in Kongsfjorden are a common occurrence. Results from the present study suggest that Greenland sharks likely play a unique and significant role in Arctic marine food webs as a top predator of fishes and marine mammals.     

The importance of solid-phase distribution on the oral bioaccessibility of Ni and Cr in soils overlying Palaeogene basalt lavas, Northern Ireland

Potentially toxic elements (PTEs) including nickel and chromium are often present in soils overlying basalt at concentrations above regulatory guidance values due to the presence of these elements in underlying geology. Oral bioaccessibility testing allows the risk posed by PTEs to human health to be assessed; however, bioaccessibility is controlled by factors including mineralogy, particle size, solid-phase speciation and encapsulation. X-ray diffraction was used to characterise the mineralogy of 12 soil samples overlying Palaeogene basalt lavas in Northern Ireland, and non-specific sequential extraction coupled with chemometric analysis was used to determine the distribution of elements amongst soil components in 3 of these samples. The data obtained were related to total concentration and oral bioaccessible concentration to determine whether a relationship exists between the overall concentrations of PTEs, their bioaccessibility and the soils mineralogy and geochemistry. Gastric phase bioaccessible fraction (BAF %) ranged from 0.4 to 5.4 % for chromium in soils overlying basalt and bioaccessible and total chromium concentrations are positively correlated. In contrast, the range of gastric phase BAF for nickel was greater (1.4–43.8 %), while no significant correlation was observed between bioaccessible and total nickel concentrations. However, nickel BAF was inversely correlated with total concentration. Solid-phase fractionation information showed that bioaccessible nickel was associated with calcium carbonate, aluminium oxide, iron oxide and clay-related components, while bioaccessible chromium was associated with clay-related components. This suggests that weathering significantly affects nickel bioaccessibility, but does not have the same effect on the bioaccessibility of chromium.