This study has been carried out to understand the geochemistry of elements namely, iron (Fe) and phosphorus (P) in the core sediments of an urbanized tropical mangrove ecosystem along the Southwest coast of India. The study revealed the coupling of iron and phosphorus in which the reductive conditions induced reductive dissolution and upward transport of Fe, causing surface coprecipitation of phosphorus incorporated Fe oxyhydroxides. The accumulation and transformation of phosphorus were significantly influenced by processes viz.
View Article and Find Full Text PDFDistribution and ecological risk assessment of trace metals were carried out in the core sediments of a highly urbanized tropical mangrove ecosystem along the Southwest coast of India. The metal distribution pattern was as follows: Co, Cu, Ni and Pb adsorbed onto Fe oxyhydroxides and fine grained sediments; Cd and Zn preferential adsorption by organic matter and Cr scavenging by Mn oxyhydroxides. Cd, Pb and Zn were significantly enriched in upper sediments, while Cd, Ni and Zn were present in metal exchangeable fractions.
View Article and Find Full Text PDFFlexible micro-cellular open porous 3D polymer foam silica aerogel composites with exceptional oil sorption characteristics were prepared by implanting silica aerogel in the interstices of foam substrates. Silica aerogels were engineered from silane precursors namely tetraethoxysilane (TEOS) and methyltrimethoxysilane (MTMS) adopting economical, energy efficient and scalable ambient pressure drying technique. These flexible composites exhibited outstanding structural ruggedness.
View Article and Find Full Text PDFDistribution and ecological risks of Phthalic acid esters (PAEs) are poorly studied in estuarine environments in India. An attempt is made to chart the sources and assess the ecological risk of six PAE congeners (∑PAEs), present in dissolved and particulate forms in a tropical ecosystem (Cochin Estuary, India). Terrestrial input, as attested by a clear seasonality with substantial enrichment during monsoon (2-28 μg/L and 31-1203 μg/g; dissolved and particulate PAEs respectively) and post-monsoon (1-7 μg/L and 7-321 μg/g; dissolved and particulate PAEs respectively), was identified as the primary source.
View Article and Find Full Text PDFBackground: Perchlorate is an anion that occurs as a contaminant in groundwater. It originates from the improper disposal of ammonium perchlorate, a component of rocket fuel. The objective of this study was to explore whether the exposure to perchlorate in drinking water had an impact on the thyroid function of the population residing near an ammonium perchlorate plant in Kerala.
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