Kurunthachalam Senthil Kumar

Polychlorinated dibenzo-p-dioxins, dibenzofurans and polychlorinated biphenyls in polar bear, penguin and south polar skua

Concentrations of 2378-substituted polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (DFs) and non- and mono-ortho-substituted polychlorinated biphenyls (dioxin-like PCBs) were measured in livers of polar bears from the Alaskan Arctic and in eggs of Adelie penguin and south polar skua and weddell seal liver, fish and krill from Antarctica. This is one of the first reports to document the concentrations of PCDDs/DFs in polar bear livers from Alaska, and in penguin and skua eggs from Antarctica. Concentrations of total PCDD/DFs in livers of polar bears ranged from 8 to 66 (mean: 26) pg/g, on a lipid weight basis. Concentrations of total PCDD/DFs in Antarctic samples were in the increasing order on a lipid weight basis; weddell seal liver (8.9 pg/g) < fish (11-17 pg/g) < krill (27 pg/g) <penguin eggs (mean: 23 pg/g) < south polar skua eggs (mean: 181 pg/g). Concentrations of dioxin-like PCBs (including two di-ortho congeners) in polar bear livers were in the range of 1,080-3,930 ng/g, lipid wt. Concentrations of dioxin-like PCBs in Antarctic samples were in the following order on a lipid weight basis; south polar skua eggs (mean: 1,440 ng/g) > > penguin eggs (30 ng/g) > seal liver (57 ng/g) > fishes (6.2 ng/g) > krill (0.9 ng/g). Concentrations of 2378-tetrachlorodibenzo-p-dioxin equivalents (TEQs) calculated based on the WHO TEFs were higher in the eggs of polar skua (mean: 344: range: 220-650 pg/g, lipid wt.) from Antarctica than in polar bear livers from Alaska (mean: 120; range: 69-192 pg/g). In general, concentrations of PCDFs were greater than those of PCDDs in polar organisms. 23478-PeCDF is one of the dominant congener found in several samples. Concentrations of TEQs in polar bear livers and skua eggs were close to those that may cause adverse health effects. Dioxin-like PCBs, particularly, non-ortho coplanar PCBs were the major contributors to TEQ concentrations in penguin and skua eggs whereas mono-ortho PCBs accounted for a major portion of TEQs in polar bear livers.

Distribution, partitioning, bioaccumulation of trace elements in water, sediment and fish from sewage fed fish ponds in eastern Kolkata, India

Concentrations of trace elements were measured in water (Cu, Zn, Fe, Pb, Mn, and Al), sediment (Cr, Cu, Mn, Pb, Ni, Al, Zn, Fe, and Co), and muscle tissue of nine selected fish species (Cu, Zn, Fe, and Mn) collected from eastern Kolkata (India) estuarine-sewage fed fish ponds. In water, trace elements existed in particulate phase (60–80%) with Fe as the predominant element followed by Al > Mn > Zn > Pb > Cu. The partitioning coefficients (Kd ) of the trace elements are low and fairly stable. The Pearson product moment correlation among the elements in the particulate and dissolved phase of the water column was calculated and most of the elements are correlated well (p ≤ 0.005). The trace element concentrations in sediments were in the following order: Al ≥ Fe > Mn > Zn > Cu > Ni > Cr > Pb > Co. Contamination factors (CFs) of trace elements in sediments were in the order of Pb ≥ Cu > Zn > Fe > Mn ≥ Ni ≥ Co > Al > Cr and Pollution Load Index ranges were 0.33–0.56. The CFs for Pb, Cu, and Zn are 0.92, 0.88, and 0.73, respectively, shows natural as well as anthropogenic inputs of these elements into the Kolkata sewage fed fish ponds. Accumulation of trace elements in muscle tissue of nine selected fish species were, Fe > Zn ≫ Cu > Mn Silver carp contained high Cu and Fe, American rohu contained high Zn concentration while Nylontica species contained high Mn concentration. Bio-concentration factor and bio-accumulation factor of elements, (Fe, Zn, Cu, and Mn) in fish, showed positive and negative accumulation factors when calculated against elements in the dissolved and suspended particulate matter phase of water, respectively. Iron (Fe), Mn, and Zn concentration in fish tissue were greater than WHO/FAO certified values; therefore, regular monitoring of trace elements is warranted for fish tissue collected from these estuarine-sewage fed fish ponds.

Persistent organochlorine pesticides, polychlorinated biphenyls, polybrominated diphenyl ethers in fish from coastal waters off Savannah, GA, USA

Contamination profiles of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs) were determined in six fish species from three selected regions along coastal waters off Savannah, GA, USA. Concentrations of PCBs were predominant (12–493 ng g−1 lw) followed by PBDEs (10–337 ng g−1 lw), OCPs such as DDTs (2.7–153 ng g−1 lw), chlordanes (3.8–34 ng g−1 lw), cyclodienes (<0.1–35 ng g−1 lw), mirex (<0.1–8.6 ng g−1 lw), γ-hexachlorocyclohexane (<0.1–1.4 ng g−1 lw), and hexachlorobenzene (<0.1–0.68 ng g−1 lw). The results indicated no region-specific difference in the contaminants however inter-species as well as intra-species differences were evident. Comparison of DDTs, PCBs, and PBDEs profiles in fish with those from other countries revealed that fish from coastal waters off Savannah contained relatively less concentrations of PCBs and chlorinated pesticides, while PBDE concentrations were comparable or even higher than fish samples from other regions. Polychlorinated biphenyl congeners and chlorinated pesticide tempoal trend data exhibited no increase of contamination levels. The levels of PCBs and chlorinated pesticides in fish from Savannah coastal waters were below the Food and Drug Administrations (FDA) established limits for human consumption.

Autoimmune thyroid disease in patients with vitiligo: prevalence study in India.

OBJECTIVE To identify the prevalence of autoimmune thyroid disease (AITD) in Asian Indian patients with vitiligo and to compare the clinical profile between thyroid peroxidase (TPO) antibody-positive and TPO antibody-negative groups. METHODS In this cross-sectional, case-controlled study, 50 patients with vitiligo (29 women and 21 men) were included. Patients with previous disorders, irradiation, or surgical procedures involving the thyroid were excluded from the study. All participants underwent a complete physical examination, and a single fasting blood sample was analyzed for thyroid function (triiodothyronine, thyroxine, thyroid-stimulating hormone, and TPO and thyroglobulin antibodies), inflammatory and immunologic markers (erythrocyte sedimentation rate, C-reactive protein, and rheumatoid factor), and serum calcium, phosphorus, and alkaline phosphatase concentrations. All patients underwent thyroid ultrasonography, and the data were analyzed by appropriate statistical methods. RESULTS The mean age of the study participants was 42.7 ± 17 years, and 14 of 50 patients (28%) had TPO antibody positivity. A goiter was present in 11 of 50 patients, and the thyroid volume by ultrasonography was similar between the 2 groups. Subclinical hypothyroidism was found in 14 of 50 patients (28%) but more frequently in the TPO antibody-positive group (8 of 14 or 57%) than in the TPO antibody-negative group (6 of 36 or 17%). The prevalence of AITD was 20 of 50 patients (40%) when the TPO antibody-positive group and those with subclinical hypothyroidism were considered collectively. None of the patients had overt hypothyroidism or hyperthyroidism. All other clinical, biochemical, and inflammatory variables did not differ significantly between the TPO antibody-positive and antibody-negative groups. CONCLUSION Our data showed a 40% prevalence of thyroid disease in patients with vitiligo in India. The risk is exacerbated in patients with thyroid autoimmunity; thus, regular screening of patients with vitiligo for AITD is needed.

Chlorinated hydrocarbon contaminants in blood of black and turkey vultures from Savannah River Site, South Carolina, USA

Blood of adult and juvenile black and turkey vultures in the Savannah River Site of South Carolina, USA was analyzed for the presence of 2,3,7,8-chlorine substituted polychlorinated dibenzo-p-dioxins (2,3,7,8-PCDDs), dibenzofurans (2,3,7,8-PCDFs), -dioxin-like and -di-ortho polychlorinated biphenyls. Concentration ranges of 2,3,7,8-PCDD/DFs in blood of black and turkey vultures were 14.2-34.6 and 8.7-56.2 pg/ml wet wt., respectively. Dioxin-like PCBs were in the ranges of 815-4627 and 753-3611 pg/ml wet wt. respectively, in black and turkey vultures. Considerable concentrations of two congeners of di-ortho PCBs were noticed in the ranges of 1415-10325 and 663-7500 pg/ml respectively, in black and turkey vultures. Comparatively, greater toxic equivalency (TEQ) were observed in blood of turkey vultures with the ranges of 3.2-20, whereas black vulture contained 1.8-8.4 pgTEQ/ml wet wt. basis. The species-specific accumulation profiles of PCDD/DFs and dioxin-like PCBs may reflect the different feeding habits, ecology, metabolic capacity and migratory movements of these two scavenging species.

Extremely hydrophobic Aroclor 1268 and residues of polybrominated diphenyl ethers (PBDEs) in marsh sediment collected from Superfund Site in Brunswick, Georgia, USA

Among the several man-made chemicals, polychlorinated biphenyls (PCBs) are known for their contamination in the global environment, biomagnification in the food chain, and long-term health effects on aquatic and terrestrial animals including humans (Loganathan and Kannan, 1991; Loganathan et al., 2001, 2007; Senthil Kumar et al., 1999a,b, 2001a,b). Although PCBs were banned for production and use in open systems since 1970s, there are several PCB-contaminated Superfund Sites in the United States and these sites were protected to limit dispersal of PCBs from these sites. However, volatilization and leaching of contaminants from these sites continue to occur. Linden Chemicals and Plastics (LCP) Superfund Site is located on Ross Road in Brunswick (Glynn County), Georgia State, USA is one among them. As a result of multi-industrial operations, including an oil refinery (Atlantic Richfield Company, 1919–1935, Georgia electrical power generating facility, 1935–1955, and Dixie Paint and Varnish 1941–55) at this site, the adjacent brackish water have been severely contaminated by metals (mercury, lead, chromium and zinc) and organics (PCBs, PAHs and phenolic compounds) (Kannan et al., 1997; USEPA, 1995). A chlor-alkali plant was established on the site in 1955 and operated until 1994, when it was proposed for listing on the National Priority List (NPL) in October 1995 (USEPA, 1995, 1997). Arolcor 1268 is a highly chlorinated PCB formulation which was applied to electrical equipment used in the chlor-alkali process at the LCP site (Kannan et al., 1997; Loganathan et al., 1998). This site is bordered by the Purvis Creek, Turtle River, Gibson Creek, and salt marshes to the west, mixed residential and commercial areas to the north, and Terry Creek, mixed residential and industrial areas to the east and south. This roughly includes an 80 acre industrialized upland portion, and over 550 acres of salt marsh and tidal creeks (Kannan et al., 1997, 1998a,b; Loganathan et al., 1997; Maruya and Lee, 1998a). LCP purchased a type of PCBs called Aroclor 1268 from the sole manufacturer, which only produced a limited amount of this particular Aroclor (Kannan et al., 1997). This PCB has been found at very high levels in the marshes directly adjacent to LCP, thus making it a direct fingerprint to the point source of the pollution. Representative studies from United States Fish and Wildlife Service (USFWS) documented the extent of the damage to wildlife resources (Andrews, 1989; Lind et al., 1999; Gaines et al., 2000, 2003). A study by Newall and Wall (1998) demonstrated contaminated estuarine sediments possess microbial consortia with diverse dehalogenating activities, lack of dechlorination of Aroclor 1268 and spiked nonachlorobiphenyl congeners (experimental study) suggests a bioavailability limitation or enzyme–substrate incompatibles to fungi (Cutkomp et al., 1972). Although this research helped the USFWS quantify damage to the ecosystem, it left many unanswered questions. Specifically, it inspired the hypothesis that the LCP marsh may be what is commonly referred to as an

Accumulation of Polychlorinated Biphenyls in Pine Needles Collected from Residential and Industrial Areas in Western Kentucky

ABSTRACT One-year-old pine needles collected from residential and industrial locations in Kentucky were analyzed for polychlorinated biphenyls. For comparison, pine needle samples from the highly contaminated Linden Chemicals and Plastics (LCP) Superfund site in Brunswick, Georgia, also were analyzed. PCB concentrations in residential Kentucky ranged from 1.91 ng/g dry wt. to 12 ng/g dry wt. These sites were comparatively less polluted than those from the Superfund site, that had concentrations ranging from 15 ng/g dry wt. to 34 ng/g dry wt. Finger printing of PCB contamination sources was possible using pine needle PCB profiles. PCB-28 and PCB-52, PCB-101, PCB-153 and PCB-138 in pine needles indicated uptake of Aroclors −1016 and −1242, −1254, −1260 in Kentucky sites. Pine needles from the Superfund site and its vicinity contained higher chlorinated PCBs especially, PCB-196, PCB-199, and PCB-206 characteristic of Aroclor 1268. When the toxic equivalencies (TEQs) of PCBs were compared, Kentucky pine needles were only slightly lower (0.03–0.17 pg/g dry wt) than pine needles from the Superfund site (0.24–0.48 pg/g dry wt). Considering the homologue distribution of PCBs in pine needles from Kentucky and the Superfund site, lower chlorinated PCBs seem to have traveled farther than the higher chlorinated PCBs.

IROLS Based Radial Basis Function Neural Network for Face Recognition

Face representation (FR) plays a typically important role in face recognition and methods such as principal component analysis (PCA) and linear discriminant analysis (LDA) have been received wide attention recently. These FR methods will inevitably lead to poor classification performance in case of great facial variations such as expression, lighting, occlusion and so on, due to the fact that the image gray value matrices on which they manipulate are very sensitive to these facial variations .The recognition of faces is very important because of its potential commercial applications, such as in the area of video surveillance, access control systems, retrieval of an identity from a data base for criminal investigations and user authentication. The recognition performance of the face recognition system deteriorates when the system is exposed to the real world scenario. This problem happens because we do not have a complete set of training samples that consists of all types of visual variations. Furthermore, the extendibility of the system to recognize more new people who join the existing groups in the future may cause a problem to the system. In this work, a radial basis function (RBF) neural network with a new incremental learning method based on the regularized orthogonal least square (ROLS) algorithm is proposed for face recognition. It is designed to accommodate new information without retraining the initial network. In addition, it accumulates previous experience and learns updated new knowledge of the existing groups to increase the robustness of the system. The proposed work is to be developed on Matlab platform for its realization. Index Terms —Face recognition, incremental learning, neural network, orthogonal least square, radial basis function (RBF), visual variation. In this paper, we propose a new incremental learning method for the regularized orthogonal least square (ROLS)-based radial basis function (RBF) neural network. This proposed al- algorithm is named as the incremental ROLS (IROLS) algorithm. The IROLS algorithm is designed to accommodate a new class and updated new data while avoiding retraining the network. The IROLS algorithm combines the zero-order regularization with the orthogonal least square to construct a parsimonious RBF network to improve the generalization ability of the system. This algorithm is capable of constructing small RBF networks which generalize well and requires low computational complexity. For the conventional ROLS algorithm, it first selects the basis vector that provides the most significant error reduction among all the basis vectors and orthogonalizes all the remaining basis vectors into a Euclidean space formed by the selected basis vector. This process will be

Effects of surface fire on litter decomposition and occurrence of microfungi in a Cymbopogon polyneuros dominated grassland

Abstract Litter decomposition rate, changes in macronutrients such as nitrogen (N), phosphorus (P) and potassium (K) from different grades of litter decomposition and occurrence of soil microfungi were investigated in a Cymbopogon polyneuros-dominated tall grass ecosystem from a burned and an unburned site in southern India. The litter decomposition rate was higher at the burned site than at the unburned site. This rate was also higher when the litter was mixed with the mineral soil material than leaving the litter unaffected on the soil surface. The concentrations of N, P, and K in the litter decreased as a result of progressed litter decomposition. Occurrence of microfungi identified from the different decomposition grades of the Cymbopogon polyneuros litter was higher at the burned site compared to the unburned site. Microfungal species present at both sites showed only minor differences.