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The most prevalent pollutant, polycyclic aromatic hydrocarbons (PAHs) is now plenteously distributed in the global atmosphere. We recently quantified 36 polycyclic aromatic hydrocarbons (PAHs) associated with aerosols (particulate matter: PM) in five Asian cities: Tokyo (Japan), Beijing (China), Kolkata (India), Hanoi (Vietnam), and Kuala Lumpur (Malaysia). Average atmospheric PAH concentrations (Σ12 PAHs-ng m^(–3)) increased in the order of Kuala Lumpur (2.99) ≈ Tokyo (3.95) ＜ Hanoi (7.99) ＜＜ Kolkata (63.5) ＜＜ Beijing (142.8). The most abundant PAHs in PM samples in these cities were chrysene, benz[a]anthracene, benzofluoranthenes, benzo[a]pyrene, and benzo[e]pyrene. We used the PAH compositions, especially the relative abundances of alkylated PAHs, and hopanes to determine vehicle exhaust-derived PAHs, and levoglucosan as a tracer for biomass burning, especially from wood combustion. Vehicle exhaust contributed to atmospheric PAHs in all cities, indicated by higher ratios of (C_(30)17α)/total PAHs and MPAHs/PAHs than coal and wood combustion products. Coal combustion contributed also in winter aerosols in Beijing, indicated by higher abundance of β isomers i.e., 17β21β (H)-C30hopane (C_(30)17β) and 17β21β (H)-C_(29)hopane (C_(29)17β) signifying mass use of coal for heating. The ratio of levoglucosan/PAHs was high in Kuala Lumpur and Hanoi, suggesting greater inputs of PAHs from biomass burning there.

Considering the magnitude of pollution caused by marine plastics, the present study assessed their abundance, distribution, surface morphology and polymer type in ten sandy beaches spread across three states (Maharashtra, Karnataka and Goa) along the west coast of India (WCI). The total abundance of plastics (∼1–100 mm) in the studied beaches ranged from 4.1 to 23.4% (19±1–346 ± 2 items/m2). Location-wise, the abundances of both micro (43.6 ± 1.1–346 ± 2 items/m2) and macroplastics (21.6±3–195 ± 6 items/m2) were relatively higher in beaches along the Maharashtra coast. Surface morphology-wise, fragments were predominantly abundant in both micro (76±2–346 ± 2 items/m2) and macroplastics (50.6 ± 1.5–195 ± 6 items/m2) followed by pellets (43.3 ± 2.5–245.6 ± 2 items/m2). Fourier-transform infrared spectroscopy (FT-IR) analysis of plastics revealed a dominance of polyethylene (PE) followed by polypropylene (PP). IR spectra of the collected plastics at absorption band at 1750–1700 cm−1 reflect minimal surface oxidation. White-colored plastics were observed most frequently, followed by pale-yellow, dark-brown, green, blue, transparent and red. A short-term (72 h) experimental study to assess the toxicity of PE microbeads (∼1 mm) in a commercially important shrimp species, Litopenaeus vannamei revealed toxicological changes. An elevated level of lipid peroxidation (LPX)—the tagged biochemical marker, was recorded only at the maximum dose (0.15 mg/L) of PE microbeads. A moderate increase in the levels of enzymatic antioxidants (catalase and glutathione S-transferase) was also recorded at the same dose. Comprehensive information on marine plastics, including ecotoxicity provided in this study, would help in evolving strategies in minimizing plastic pollution along the WCI.

In June 2016, a cruise vessel was grounded in the Mormugao Port, resulting in unnoticed oil spill. The surface water and sediment samples were collected from the vicinity of the ship, and also an oil sample from the ship (OIL). These samples were subject to petroleum biomarker such as pentacyclic triterpenes (hopanes) and compound specific carbon isotopic (?13C) analyses to assess the source of hydrocarbon pollution in the Mormugao Port. While no clear trend was observed in water samples, the bottom surface sediments did show an identical pattern of hopanes with the oil. The chemometric analyses of hopane Diagnostic Ratios (DRs) and ?13C ratios confirmed the ship oil as the source of oil pollution in sediments. Whereas the water is comparatively more dynamic than the sediment, the physical processes arising out of winds, waves, tides and currents might have dispersed the oil away from the grounded ship. - 2019 Elsevier Ltd We thank the Director, CSIR-NIO, Goa, for his constant support and interest in this study. We thank the Goa State Pollution Control Board for funding this project. Thanks to the GSPCB officials for their kind support during sample collection. Thanks to Dr Aninda Mazumdar and Dr Siby Kurian for providing ASE and Sample concentrator facilities. We also thank Sonam and Adarsh for their assistance during sample processing. This is CSIR-NIO contribution number 6400. Appendix A Scopus

The utility of ginkgo leaves as biomonitors of airborne polycyclic aromatic hydrocarbons (PAHs) was evaluated. We investigated PAH concentrations among tree species, the effect of variations in leaf position in a tree, tissue distributions, correlations between ginkgo leaves and air, and seasonal variations. Among the five species examined ( Ginkgo biloba L., Zelkova serrata Makino, Liriodendron tulipifera L., Prunus yedoensis Matsum, and Magnolia kobus DC.), ginkgo accumulated the greatest amount of PAHs from roadside air. Most PAHs (∼80%) were accumulated in the wax fraction, and most of the remainder (17%) penetrated the inner tissues of the leaves. PAH concentrations in ginkgo leaves decreased with increasing height and distance from the road, reflecting the derivation of PAHs from vehicle emissions. Seasonal time-series sampling showed that PAH concentrations in ginkgo leaves increased with time, attributable to the effects of temperature and accumulation through long-term exposure. Concentrations in ginkgo leaves collected from various roads showed a strong and significant correlation with those in air collected by a high-volume air sampler ( r 2 = 0.68, P

Various source materials such as crude oil, automobile exhaust, coal, and wood combustion products were analyzed for polycyclic aromatic hydrocarbons (PAHs) and hopanes. Hopanes were detected in coal combustion-derived soot, along with petrogenic sources. Based on the correlation between the alkylated PAHs/parental PAHs ratio with their respective C30 hopane/PAHs ratio in these source materials, the criteria for differentiating the petrogenic and pyrogenic sources of PAHs were established. This study concluded that sediments contained exclusively pyrogenic PAHs when the following conditions were met: MP/P (methylphenanthrenes to phenanthrene) = 0.5, MPy/Py [(methylpyrenes + methylfluoranthenes) to (pyrene + fluoranthene)] = 0.15, and MC/C [(methylchrysenes + methylbenz[a]anthracenes) to (chrysene + benz[a]anthracene)] = 0.2. By contrast, the sediments contained exclusively petrogenic PAHs when the ratios of MP/P, MPy/Py, MC/C, and methyl PAHs (MPAHs)/PAHs exceeded 3.5, 1.5, 2.0, and 2.2, respectively. Bas...

Perfluorinated surfactants (PFSs) in Asian freshwater fish species were analyzed to investigate tissue distribution, temporal trends, extent of pollution, and level of PFS exposure through food intake. Freshwater fish species, namely carp, snakehead, and catfish, were collected in Japan, Vietnam, India, Malaysia, and Thailand, and 10 PFSs, including perfluorooctanesulfonate (PFOS) and perfluorooctanoate, were analyzed by liquid chromatography–tandem mass spectrometry. PFSs in carp in Tokyo were more concentrated in kidneys (Σ10 PFSs = 257 ± 95 ng/g wet weight [ww]) and livers (119 ± 36 ng/g ww) than in ovaries (43 ± 2 ng/g ww) and muscles (24 ± 17 ng/g ww). Concentrations of PFOS and its precursor, perfluorooctane sulfonamide, in livers of carp and in waters in Tokyo showed a dramatic decrease during the last decade, probably because of 3 M’s phasing-out of the manufacture of perfluorooctanesulfonyl-fluoride-based products in 2000. In contrast, continuing contamination by long-chain perfluorocarboxylates (PFCAs) with ≥ 9 fluorinated carbons was seen in multiple media, suggesting that these compounds continue to be emitted. PFS concentrations in freshwater fish species in tropical Asian countries were generally lower than those in developed countries, such as Japan, e.g., for PFOS in muscle, Vietnam < 0.05–0.3 ng/g ww; India < 0.05–0.2 ng/g ww; Malaysia < 0.05–0.2 ng/g ww; Thailand < 0.05 ng/g ww; and Japan (Tokyo) = 5.1–22 ng/g ww. Daily intake of short-chain PFCAs with ≤ 8 fluorinated carbons from freshwater fish species in Japan was approximately one order of magnitude lower than that from drinking water, whereas daily intake of PFOS and long-chain PFCAs with ≥ 9 fluorinated carbons from freshwater fish species was comparable with or greater than that from drinking water. Because the risk posed by exposure to these compounds through intake of fish species is a matter of concern, we recommend the continued monitoring of PFS levels in Asian developing countries.

Plastics debris in the marine environment, including resin pellets, fragments and microscopic plastic fragments, contain organic contaminants, including polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons, petroleum hydrocarbons, organochlorine pesticides (2,2′-bis( p- chlorophenyl)-1,1,1-trichloroethane, hexachlorinated hexanes), polybrominated diphenylethers, alkylphenols and bisphenol A, at concentrations from sub ng g –1 to µg g –1 . Some of these compounds are added during plastics manufacture, while others adsorb from the surrounding seawater. Concentrations of hydrophobic contaminants adsorbed on plastics showed distinct spatial variations reflecting global pollution patterns. Model calculations and experimental observations consistently show that polyethylene accumulates more organic contaminants than other plastics such as polypropylene and polyvinyl chloride. Both a mathematical model using equilibrium partitioning and experimental data have demonstrated the transfer of contaminants from plastic to organisms. A feeding experiment indicated that PCBs could transfer from contaminated plastics to streaked shearwater chicks. Plasticizers, other plastics additives and constitutional monomers also present potential threats in terrestrial environments because they can leach from waste disposal sites into groundwater and/or surface waters. Leaching and degradation of plasticizers and polymers are complex phenomena dependent on environmental conditions in the landfill and the chemical properties of each additive. Bisphenol A concentrations in leachates from municipal waste disposal sites in tropical Asia ranged from sub µg l –1 to mg l –1 and were correlated with the level of economic development.

Detailed analyses of persistent organic pollutants (POPs) such as hexachlorocyclohexane (HCH) isomers (HCHs), dichlorodiphenyltrichloro ethane (DDT) and its metabolites (DDTs), hexachlorobenzene (HCB) and congeners of polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) in surface sediments from the coastal estuarine environment of West Bengal, northeast India allowed the evaluation of the contamination status, distribution and possible pollution sources. HCH, DDT, HCB, PCB and PAH were identified compounds in all the samples, whereas the concentrations of chlorinated pesticides (trans-eptachlorepoxide, dieldrin, endrin, metaoxychlor and mirex) were below the detection limits and were not of great concern. The pesticides did demonstrate markedly different distributions reflecting different agricultural and domestic usage in the region. The range of concentrations of HCH, HCB, DDT and PCBs in the sediments were 0.11–0.40

To understand the spatial variation in concentrations and compositions of organic micropollutants in marine plastic debris and their sources, we analyzed plastic fragments (∼10 mm) from the open ocean and from remote and urban beaches. Polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), dichloro-diphenyl-trichloroethane and its metabolites (DDTs), polybrominated diphenyl ethers (PBDEs), alkylphenols and bisphenol A were detected in the fragments at concentrations from 1 to 10,000 ng/g. Concentrations showed large piece-to-piece variability. Hydrophobic organic compounds such as PCBs and PAHs were sorbed from seawater to the plastic fragments. PCBs are most probably derived from legacy pollution. PAHs showed a petrogenic signature, suggesting the sorption of PAHs from oil slicks. Nonylphenol, bisphenol A, and PBDEs came mainly from additives and were detected at high concentrations in some fragments both from remote and urban beaches and the open ocean.

We collected surface sediment samples from 174 locations in India, Indonesia, Malaysia, Thailand, Vietnam, Cambodia, Laos, and the Philippines and analyzed them for polycyclic aromatic hydrocarbons (PAHs) and hopanes. PAHs were widely distributed in the sediments, with comparatively higher concentrations in urban areas (Sigma PAHs: approximately 1000 to approximately 100,000 ng/g-dry) than in rural areas ( approximately 10 to approximately 100g-dry), indicating large sources of PAHs in urban areas. To distinguish petrogenic and pyrogenic sources of PAHs, we calculated the ratios of alkyl PAHs to parent PAHs: methylphenanthrenes to phenanthrene (MP/P), methylpyrenes+methylfluoranthenes to pyrene+fluoranthene (MPy/Py), and methylchrysenes+methylbenz[a]anthracenes to chrysene+benz[a]anthracene (MC/C). Analysis of source materials (crude oil, automobile exhaust, and coal and wood combustion products) gave thresholds of MP/P=0.4, MPy/Py=0.5, and MC/C=1.0 for exclusive combustion origin. All the combustion product samples had the ratios of alkyl PAHs to parent PAHs below these threshold values. Contributions of petrogenic and pyrogenic sources to the sedimentary PAHs were uneven among the homologs: the phenanthrene series had a greater petrogenic contribution, whereas the chrysene series had a greater pyrogenic contribution. All the Indian sediments showed a strong pyrogenic signature with MP/P approximately 0.5, MPy/Py approximately 0.1, and MC/C approximately 0.2, together with depletion of hopanes indicating intensive inputs of combustion products of coal and/or wood, probably due to the heavy dependence on these fuels as sources of energy. In contrast, sedimentary PAHs from all other tropical Asian cities were abundant in alkylated PAHs with MP/P approximately 1-4, MPy/Py approximately 0.3-1, and MC/C approximately 0.2-1.0, suggesting a ubiquitous input of petrogenic PAHs. Petrogenic contributions to PAH homologs varied among the countries: largest in Malaysia whereas inferior in Laos. The higher abundance of alkylated PAHs together with constant hopane profiles suggests widespread inputs of automobile-derived petrogenic PAHs to Asian waters.

This paper reports the result of sewage pollution monitoring conducted in South and Southeast Asia during 1998-2003 using linear alkylbenzenes (LABs) as molecular tracers of sewage contamination. Eighty-nine water samples collected from Malaysia, Vietnam, and Japan (Tokyo), and 161 surface sediment samples collected from Tokyo, Thailand, Malaysia, Philippines, Vietnam, Cambodia, Indonesia, and India were analyzed for alkylbenzenes. The concentration range of SigmaLABs in river water particles in Southeast Asia (0.005-0.913 microg/L) was comparable to or higher than those found in Tokyo (0.005-0.638 microg/L). I/E ratios (a ratio of internal to external isomers of LABs) in tropical Asian waters were close to the value of LABs in raw sewage ( approximately 1) and much lower than those in secondary effluents (3-5). This suggests that untreated or inadequately treated sewage is discharged into the water. SigmaLABs concentrations in sediments from South and Southeast Asia ranged from0.002-42.6 microg/g-dry with the highest concentration occurring at several populous cities. Low I/E ratios of the sediments with high SigmaLABs concentrations suggest a heavy load of untreated sewage. Clearly in view of the current data and evidence of the implications of sewage pollution, this paper highlights the necessity of the continuation of water treatment system improvement in tropical Asia.