A study on vertical distribution of magnetic susceptibility, carcinogenic and endocrine disrupting PAHs was performed in the reclaimed mudflat sediments adjacent to the Thane Creek of Mumbai. The 5-rings PAHs and ΣC-PAHs were more... more
A study on vertical distribution of magnetic susceptibility, carcinogenic and endocrine disrupting PAHs was performed in the reclaimed mudflat sediments adjacent to the Thane Creek of Mumbai. The 5-rings PAHs and ΣC-PAHs were more dominant at 120 cm depth contributing 52.23% and 60.19% respectively to ∑PAHs. The average ratio values of LMW/HMW PAHs (0.58); Fla/(Fla + Pyr) (0.50); Ant/(Ant + Phe) (0.50); BaA/(Chry + BaA) (0.48); BaP/BghiP (2.06), Phe/Ant (1.03) and BaA/Chr (0.93) indicate that the PAH contamination might have raised due to inefficient combustion and pyrogenic emissions during the open burning of solid waste in the vicinity. This was further supported by the anthropogenic ferri(o)magnetic loading over the last 100 years influencing the Creek sediments. The PAHs toxicity estimation was performed by calculating the toxic equivalent quantity (TEQ) value of 8.62 ng TEQ/g which was below the safe level (600 ng TEQ/g) suggested by the Canadian risk-based soil criterion for protection of human health.
This study investigated the levels, sources and potential risks of 17 polycyclic aromatic hydrocarbons in surface sediment samples collected along the Mithi River of Mumbai. The concentration level of ΣPAHs found in the present study was... more
This study investigated the levels, sources and potential risks of 17 polycyclic aromatic hydrocarbons in surface sediment samples collected along the Mithi River of Mumbai. The concentration level of ΣPAHs found in the present study was in the range of 1206–4735 ng/g dw. The composition patterns of PAHs by ring size in sediment were surveyed which indicate the dominance of four rings followed by five and three ring PAHs. In the study it was observed that the high molecular weight PAHs (HMW PAHs) made greater contributions of 90.83% as compared to that of low molecular PAHs (LMW PAHs) contributing to 9.17% to the total PAH concentrations. Toxicity and biological risk were assessed using toxic equivalent quantity and sediment quality guideline quotient. It is feared that the pollution level of PAHs in the sediments might increase in coming times resulting in an unconspicuous risks for the environment and humans through food chains.
Removal of Polycyclic Aromatic Hydrocarbons (PAHs) from the environment is important because of their potentially deleterious affect human health. Biological methods that was applied in the present study is typically contain microbial... more
Removal of Polycyclic Aromatic Hydrocarbons (PAHs) from the environment is important because of their potentially deleterious affect human health. Biological methods that was applied in the present study is typically contain microbial processes. It is the most innocuous and effective Original Research Article
The catalytic oxidation with Cerium (IV) in an aqueous solution offers an economical and environmentally safe alternative for oxidation reactions performed in synthetic laboratories and the chemical industry. In this paper, we have shown... more
The catalytic oxidation with Cerium (IV) in an aqueous solution offers an economical and environmentally safe alternative for oxidation reactions performed in synthetic laboratories and the chemical industry. In this paper, we have shown that the size of the copper nanoparticle is responsible for the yield of chemical change. The copper catalyst (non-nano) powder showed a 21% conversion of naphthalene to α-naphthol in 3 min under our experimental conditions. The same quantity of copper nanoparticles (size, ~ 60 nm diameter) ready by turn PVP-EG capping showed 33% conversion of naphthalene to α-naphthol that inflated to concerning 43% when 8 nm diameter capped copper nanoparticles are used. Surprisingly, 5 nm size copper nanoparticles showed no change in the yield of about 41%. [Ce(IV)-Cu(II) sulfate] system in our experimental work shows 43%, 97%, and 96% yields for oxidation of naphthalene, phenanthrene, and anthracene, respectively, in the presence of copper nanoparticles.
Marine bacterial biofilms were studied under different physicochemical conditions for enhanced bioremediation of polycyclic aromatic hydrocarbons (PAHs). Molecular characterization of ten environmental isolates was done by 16S rRNA gene... more
Marine bacterial biofilms were studied under different physicochemical conditions for enhanced bioremediation of polycyclic aromatic hydrocarbons (PAHs). Molecular characterization of ten environmental isolates was done by 16S rRNA gene sequencing. The effect of different physicochemical parameters, such as pH, salt concentration, temperature, carbon source on their biofilm production capability was monitored. Various topological parameters of the biofilms such as total biomass (EPS and cells content), thickness, roughness coefficient, diffusion distance and surface to biovolume ratio were studied using a confocal scanning laser microscope (CSLM). Among the various strains studied, the total biomass was maximum for P. aeruginosa N6P6 (106.64 mm 3 mm À2) followed by S. acidaminiphila NCW702 (26.92 mm 3 mm À2) indicating the formation of dense biofilm. Significant negative correlation (P < 0.05) was observed between the roughness coefficient of the biofilm and PAH degradation, whereas a significant positive correlation (P < 0.05) was observed between PAH (phenanthrene and pyrene) degradation and total biomass, thickness and diffusion distance of the biofilms. PAH degradation was studied both in planktonic and biofilm modes of growth. Biofilm facilitated degradation of the two PAHs was higher than the planktonic cells. This work demonstrates that the attached phenotypes of the marine bacteria showed noticeable variation in biofilm architecture and, in turn, biodegradation of PAHs.
Over the past few decades, in response to growing concerns about the impact of polycyclic aromatic hydrocarbons (PAHs) on human health, a variety of environmental forensics and geochemical techniques have emerged for studying organic... more
Over the past few decades, in response to growing concerns about the impact of polycyclic aromatic hydrocarbons (PAHs) on human health, a variety of environmental forensics and geochemical techniques have emerged for studying organic pollutants. These techniques include chemical fingerprinting, receptor modeling, and compound-specific stable isotope analysis (CSIA). Chemical fingerprinting methodology involves the use of diagnostic ratios. Receptor modeling techniques include the chemical mass balance (CMB) model and multivariate statistics. Multivariate techniques include factor analysis with multiple linear regression (FA/MLR), positive matrix factorization (PMF), and UNMIX. This article reviews applications of chemical fingerprinting, receptor modeling, and CSIA; comments on their uses; and contrasts the strengths and weaknesses of each methodology.
A radioactive tracer (181 Hf), having a marked affinity for suspended organic material, was used to map the plume of a nontreated municipal effluent entering the Mediterranean sea in front of Al Hoceı¨ma (Morocco). The distribution of the... more
A radioactive tracer (181 Hf), having a marked affinity for suspended organic material, was used to map the plume of a nontreated municipal effluent entering the Mediterranean sea in front of Al Hoceı¨ma (Morocco). The distribution of the radioactive tracer enables the identification of spots where pollutants are easily accumulated because of the complex interaction with organic matter at the surface of sediment grains. A sampling campaign, based on the radioactivity distribution, was designed to collect samples of suspended particulate matter and surface sediments, which were analyzed to determine the amounts of total organic Carbon and Sulfur, the grain size distribution and the concentrations of pollutants such as polycyclic aromatic hydrocarbons (PAHs), chlorinated pesticides, total anionic surfactants (TASs) and polychlorinated biphenyls (PCBs). This case study showed a general low level of contamination. The results allowed to define the environmental conditions when the radioactive method can be useful in monitoring urban effluents and contaminant distributions.
In this study, we attempted to use PAHs as a chemical proxy to trace the transport of land-derived mate- rials caused by the tsunami backwash to better understand how it may have affected the distribution of sedimentary deposition... more
In this study, we attempted to use PAHs as a chemical proxy to trace the transport of land-derived mate- rials caused by the tsunami backwash to better understand how it may have affected the distribution of sedimentary deposition throughout the seabed of Khao Lak coastal ar- eas. By analyzing the compositions of sedimentary PAHs in combination with application of the multivariate descrip- tive statistical techniques, PAHs were proven to be a promis- ing chemical proxy to indicate the tsunami backwash in the study area. Their spatial distribution could indicate that the tsunami backwash plays an important role in transporting an- thropogenic PAHs to the nearby coastal area as far as ap- proximately 25 km from the shoreline. In addition, the re- sults from diagnostic PAH isomer ratios suggested that road paving asphalt, originated from heavy erosion by the tsunami wave in front of Pakarang Cape, was among the identified sources of PAHs. Principle Component Analysis (PCA) re- sults provided 2 estimated land-derived sources of PAHs, which were the road dust and oil burning sources. These estimated signature sources clearly support our hypothesis that PAHs were transported from the potential sources on land and deposited into the near-shore seabed during tsunami backwash.
