Concentrations of some heavy metals in commercially important finfish and shellfish of the River Ganga

Heavy metals are dangerous to aquatic organisms and it can be bioaccumulated in the food chain leading to diseases in human. Cumulative effects of metals or chronic poisoning may occur as a result of long-term exposure even to low concentrations. The accumulation of heavy metals varies depending upon the species, environmental conditions, and inhibitory processes. Concentrations of zinc, copper, lead, and cadmium were determined in finfish and shellfish species in the Gangetic delta using a PerkinElmer Sciex ELAN 5000 ICP mass spectrometer and expressed as milligrams per kilogram of dry weight. In finfish and shellfish species the concentrations of Zn, Cu, Pb, and Cd were comparatively higher at stations 1 and 2 than the permissible level of WHO. The concentration of metals exhibited significant spatial variation and followed the order station 1 > station 2 > station 3 > station 4, which may be related to different degree of contamination in different location. The metal accumulation exhibited species specificity.     

Bayesian approach to estimating margin of safety for total maximum daily load development

A Bayesian-updating approach is presented to the estimation of total uncertainty-based Margin of Safety (MOS) for Total Maximum Daily Load (TMDL) calculations. Probability distributions are presented to construct the likelihood function, the prior probability distribution, and the posterior (total uncertainty) probability distribution. The Bayesian-updating approach is demonstrated through a case study for the Lower Amite River, Louisiana. The posterior probability distribution-based on the Bayesian approach updates the standard deviation of summer dissolved oxygen in the Amite River from 1.88 mg/L to 2.10 mg/L when the total uncertainty is considered. Results from the Bayesian-updating approach are compared with two conventional methods. The dissolved oxygen reserve based on a conventional margin of safety of 20% is estimated to be 45,682.26 kg/Day. The second conventional method, where we consider the standard deviation of 1.88 mg/L, produces a dissolved oxygen reserve of 40,516.09 kg/Day. The Bayesian approach yields the dissolved oxygen reserve of 38,614.43 kg/Day with the first level (μ-σ) of MOS, producing a deficit of 5606.65 kg/Day in dissolved oxygen. The dissolved oxygen reserve deficit increases to 23,895.13 kg/Day when the second level (μ-2σ) of MOS is used, which escalated to 42,383.52 kg/Day when the highest level (μ-3σ) of MOS is used. While the total uncertainty-based Bayesian approach is demonstrated for a TMDL development on the Amite River, the overall approach could be applied in any river system with similar available data.     

Climate change-induced salinity variation impacts on a stenoecious mangrove species in the Indian Sundarbans

The alterations in the salinity profile are an indirect, but potentially sensitive, indicator for detecting changes in precipitation, evaporation, river run-off, glacier retreat, and ice melt. These changes have a high impact on the growth of coastal plant species, such as mangroves. Here, we present estimates of the variability of salinity and the biomass of a stenoecious mangrove species (Heritiera fomes, commonly referred to as Sundari) in the aquatic subsystem of the lower Gangetic delta based on a dataset from 2004 to 2015. We highlight the impact of salinity alteration on the change in aboveground biomass of this endangered species that, due to different salinity profile in the western and central sectors of the lower Gangetic plain, shows an increase only in the former sector, where the salinity is dropping and low growth in the latter, where the salinity is increasing.     

Probing and understanding interaction of Eu(III) with γ- alumina in presenceof malonic acid

Radionuclide migration in aquatic environment is influenced by its sorption onto colloids/mineral oxides and the presence of organic complexing anions. With a view to understand the sorption of trivalent actinides by mineral oxides in presence of organic acid, in the present study, Eu(III), malonic acid (MA) and γ-alumina are considered as representatives of trivalent actinides, low molecular weight natural occurring organic acid and aluminol sites, respectively. The influence of MA on sorption of Eu(III) by γ-alumina was elucidated by batch sorption, spectroscopic techniques and surface complexation modeling, for the first time. Attenuated Total Reflection-Fourier Transform Infrared spectroscopic studies of MA sorbed on γ-alumina revealed the presence of two inner-sphere surface complexes. Batch sorption for binary (alumina-Eu(III)) and ternary (alumina-Eu(III)-MA) systems were investigated as a function of pH, Eu(III) concentration and sequential addition of Eu(III)/MA. The pH edge for Eu(III) sorption shifts to higher pH with increasing Eu(III) concentration. In ternary systems, Eu(III) sorption is significantly enhanced at pH < 4.5. Eu(III) speciation on γ-alumina is independent of addition sequence of Eu(III)/MA. Time resolved fluorescence spectroscopy of Eu(III) sorbed on γ-alumina exhibited two surface species, XOEu²⁺ and (YO)₂Eu⁺. The enhancement in I₆₁₆/I₅₉₂ and lifetime for ternary systems, as compared to binary system, at low pH, indicates the participation of Eu-MA complexes in the formation of surface species in ternary systems. The diffuse layer model has been employed to successfully model the experimental sorption profiles of binary and ternary systems, using code FITEQL 4.0, by considering the surface species identified by spectroscopic techniques.     

Logistics and supply chain management of food industry during COVID-19: disruptions and a recovery plan

Environment Systems and Decisions - An ongoing worldwide pandemic, known as Covid infection 2019 (COVID-19), influences the food supply chains significantly. In the pandemic situation, the...     

Paternal factors in recurrent pregnancy loss: an insight through analysis of non-synonymous single-nucleotide polymorphism in human testis-specific chaperone HSPA2 gene

Environmental Science and Pollution Research - Heat shock protein A2 (HSPA2) is a testis-specific molecular chaperone of the 70 kDa heat shock protein (HSP70) family and reported to play a key role...     

Understanding why consumers in China switch between wild,farmed, and synthetic bear bile products

An important rationale for legally farmed and synthetic wildlife products is that they reduce illegal, wild-sourced trade by supplying markets with sustainable alternatives. For this to work, more established illegal-product consumers must switch to legal alternatives than new legal-product consumers switch to illegal wild products. Despite the widespread debate on the magnitude and direction of switching, studies among actual consumers are lacking. We used an anonymous online survey of 1421 traditional Chinese medicine consumers in China to investigate switching among legal farmed, synthetic, and illegal wild bear bile. We examined the past consumption behavior, applied a discrete choice experiment framed within worsening hypothetical disease scenarios, and used latent class models to investigate groups with shared preferences. Bear bile consumers (86% respondents) were wealthier, more likely to have family who consumed bile, and less knowledgeable about bile treatments than nonconsumers. Consumer preferences were heterogenous, but most consumer preferences switched between bile types as disease worsened. We identified five distinct latent classes within our sample: law-abiding consumers (34% respondents), who prefer legal products and were unlikely to switch; two all-natural consumer groups (53%), who dislike synthetics but may switch between farmed and wild; and two nonconsumer groups (12%), who prefer not to buy bile. People with past experience of bile consumption had different preferences than those without. Willingness to switch to wild products was related to believing they were legal, although the likelihood of switching was mediated by preferences for cheaper products sold in legal, familiar places. We found that consumers of wild bile may switch to legal alternatives, given the availability of a range of products, whereas legal-product consumers may switch to illegal products if the barriers to doing so are small. Understanding preferences that promote or impede switching should be a key consideration when attempting to predict consumer behavior in complex wildlife markets.     

Environmental fate of chlorantraniliprole residues on cauliflower using QuEChERS technique

Chlorantraniliprole, an anthranilic diamide insecticide with novel mode of action is found effective against several lepidopteran as well as coleopteran, dipteran, and hemipteran pests. The present studies were carried out to study the dissipation pattern of chlorantraniliprole on cauliflower and to suggest suitable waiting period for the safety of consumers. Quick, easy, cheap, effective, rugged, and safe method was used for the extraction and cleanup of samples and the residues of chlorantraniliprole were estimated using high-performance liquid chromatograph (HPLC) and confirmed by liquid chromatograph–mass spectrometer and high-performance thin layer chromatograph. Following three applications of chlorantraniliprole (Coragen 18.5 SC) at recommended dose (9.25 g a.i.?ha^?1) and double the recommended dose (18.50 g a.i.?ha^?1), the average initial deposits of chlorantraniliprole were observed to be 0.18 and 0.29 mg kg^?1, respectively. These deposits were found to be less than the maximum residue limit of 2.0 mg kg^?1 prescribed by the Codex Alimentarius Commission. These residues dissipated below the limit of quantification of 0.10 mg kg^?1 after 3 and 5 days at recommended and double the recommended dosages, respectively. The half-life value (T _1/2) of chlorantraniliprole was worked out to be 1.36 days following its application at recommended dosages. Hence, the use of this pesticide at recommended dosages does not seem to pose any risk, and a waiting period of 1 day is suggested for safe consumption of cauliflower curds.     

Performance assessment of the indigenous ceramic UF membrane in bioreactor process for highly polluted tannery wastewater treatment

Environmental Science and Pollution Research - The present study evaluates the performance of an indigenously developed ceramic ultrafiltration (UF) membrane in a lab-scale membrane bioreactor...