Chronic effects and thresholds for estuarine and marine benthic organism exposure to perfluorooctane sulfonic acid (PFOS)-contaminated sediments: influence of organic carbon and exposure routes

Laccases are enzymes produced by different microbes like bacteria and fungi. These enzymes are members of the family of oxidases and are capable of oxidizing phenolics into non-toxic forms. Sediments were collected from the Marilao-Meycauayan-Obando River System, specifically from the sampling area connected to leather tanneries, which directly dump their effluents into the river. This study aimed to determine the presence of laccase activity of sediments of Meycauayan River where effluents of leather factories and tanneries are directly dumped. Concentration of the phenolic compounds from five collection sites were measured. Collected phenol - contaminated sediments were tested for laccase activity using ABTS (2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)). Laccase was extracted from the collected sediments and used for the degradation of phenol. Reduction of phenol concentration by the extracted laccase reached 79.82% to as high as90.84%with a starting phenol concentration of 27.5 mmol per sample. Three strains of phenol-degrading ligninolytic bacteria closely related to Lysinibacillus xylanilyticus, Lysinibacillus fusiformisss, and Lysinibacillus sphaericuswere identified to be present in the river’s sediment which could produce laccase and facilitate degradation of phenol.

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Effects of type and quantity of organic carbon on the bioaccessibility of polychlorinated biphenyls in contaminated sediments

Environmental Toxicology and Chemistry ◽

10.1002/etc.4073 ◽

2018 ◽

Vol 37 (5) ◽

pp. 1280-1290 ◽

Cited By ~ 3

Author(s):

Federico L. Sinche ◽

Sam A. Nutile ◽

Kara E. Huff Hartz ◽

Peter F. Landrum ◽

Michael J. Lydy

Keyword(s):

Organic Carbon ◽

Polychlorinated Biphenyls ◽

Contaminated Sediments

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THE USE OF COARSE, SEPARABLE, CONDENSED-PHASE ORGANIC CARBON PARTICLES TO CHARACTERIZE DESORPTION RESISTANCE OF POLYCYCLIC AROMATIC HYDROCARBONS IN CONTAMINATED SEDIMENTS

Environmental Toxicology and Chemistry ◽

10.1897/06-003.1 ◽

2007 ◽

Vol 26 (7) ◽

pp. 1380 ◽

Cited By ~ 2

Author(s):

Yunzhou Chai ◽

Alexander Kochetkov ◽

Danny D. Reible

Keyword(s):

Polycyclic Aromatic Hydrocarbons ◽

Organic Carbon ◽

Condensed Phase ◽

Aromatic Hydrocarbons ◽

Contaminated Sediments ◽

Carbon Particles ◽

Polycyclic Aromatic

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Quantification of dioxin in the sieved fraction of river sediment

Water Science & Technology ◽

10.2166/wst.2005.0325 ◽

2005 ◽

Vol 52 (9) ◽

pp. 225-233 ◽

Cited By ~ 1

Author(s):

H. Ozaki ◽

S. Taniguchi ◽

R. Takanami ◽

N. Shimomukai ◽

T. Hamasaki ◽

...

Keyword(s):

Grain Size ◽

Organic Carbon ◽

Size Distribution ◽

Grain Size Distribution ◽

River Sediment ◽

Contaminated Sediments ◽

Total Carbon ◽

Ignition Loss ◽

Environment Agency ◽

Nitrogen Contents

Dioxin pollution of aquatic sediments has been one of the important environmental problems in Japan. Grain size distribution and organic constituents may play important roles in dioxins contents in sediments, which have not been well investigated. This paper aims to quantify dioxins (PCDDs/Fs and co-PCBs) in sieved surface sediment fractions obtained from Kizu and Sumiyoshi Rivers in Osaka, Japan. The samples were prepared and analyzed following the ‘Manual of the Survey and Measurement of Dioxins in Sediment’ (Environment Agency of Japan, 2000). The results showed that TEQ concentrations of dioxins increased with decreasing grain size in sediment fractions. Sediment fractions with less than 20μm grain size showed the highest dioxin contents. Dioxins with five and six chlorine atoms dominated other congeners in less than 20μm fractions. The dioxin TEQ concentrations increased with total organic carbon (TOC), total carbon (TC), ignition loss (IL), total sulphur and nitrogen contents in the sediment fractions. Thus, reporting dioxin contents in sediments without considering grain size distribution may be erroneous, and conventional sedimentation and separation techniques might not be useful for treating contaminated sediments. This information can be useful for effective remediation of dioxin-contaminated sediments.

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CHRONIC EFFECTS OF CONTAMINATED SEDIMENTS ON THE URCHIN LYTECHINUS PICTUS

Environmental Toxicology and Chemistry ◽

10.1897/1552-8618(1989)8[629:ceocso]2.0.co;2 ◽

1989 ◽

Vol 8 (7) ◽

pp. 629 ◽

Cited By ~ 3

Author(s):

Bruce E. Thompson ◽

Steven M. Bay ◽

Jack W. Anderson ◽

Jimmy D. Laughlin ◽

Darrin J. Greenstein ◽

...

Keyword(s):

Contaminated Sediments ◽

Lytechinus Pictus ◽

Chronic Effects

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Electron Microscopy of Mycoplasma Pneumoniae

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100065341 ◽

1971 ◽

Vol 29 ◽

pp. 258-259 ◽

Cited By ~ 1

Author(s):

E. S. Boatman ◽

G. E. Kenny

Keyword(s):

Electron Microscopy ◽

Light Microscopy ◽

Growth Phase ◽

Hela Cells ◽

Sulfonic Acid ◽

Gamma Globulin ◽

Horse Serum ◽

Morphological Aspects ◽

The Family

Information concerning the morphology and replication of organism of the family Mycoplasmataceae remains, despite over 70 years of study, highly controversial. Due to their small size observations by light microscopy have not been rewarding. Furthermore, not only are these organisms extremely pleomorphic but their morphology also changes according to growth phase. This study deals with the morphological aspects of M. pneumoniae strain 3546 in relation to growth, interaction with HeLa cells and possible mechanisms of replication.The organisms were grown aerobically at 37°C in a soy peptone yeast dialysate medium supplemented with 12% gamma-globulin free horse serum. The medium was buffered at pH 7.3 with TES [N-tris (hyroxymethyl) methyl-2-aminoethane sulfonic acid] at 10mM concentration. The inoculum, an actively growing culture, was filtered through a 0.5 μm polycarbonate “nuclepore” filter to prevent transfer of all but the smallest aggregates. Growth was assessed at specific periods by colony counts and 800 ml samples of organisms were fixed in situ with 2.5% glutaraldehyde for 3 hrs. at 4°C. Washed cells for sectioning were post-fixed in 0.8% OSO4 in veronal-acetate buffer pH 6.1 for 1 hr. at 21°C. HeLa cells were infected with a filtered inoculum of M. pneumoniae and incubated for 9 days in Leighton tubes with coverslips. The cells were then removed and processed for electron microscopy.

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