Kurunthachalam Kannan - Academia.edu (original) (raw)

Papers by Kurunthachalam Kannan

Archives of Environmental Contamination and Toxicology, 1993

Isomer-specific concentrations of polychlorinated biphenyls (PCBs) including planar, mono- and di... more Isomer-specific concentrations of polychlorinated biphenyls (PCBs) including planar, mono- and di-ortho congeners and concentrations of DDT were determined in striped dolphins affected by a morbillivirus epizootic in the western Mediterranean in 1990. Extremely high concentrations of PCBs ranging from 94 to 670 μg/g (wet wt) were detected in the blubber. Similarly, DDT concentrations were high, between 22 and 230 μg/g (wet wt). The concentrations of three non-ortho coplanar PCBs were 43 (3,3′,4,4′-T4CB), 6.8 (3,3′,4,4′,5-P5CB), and 7.8 (3,3′,4,4′,5,5′-H6CB) ng/g (wet wt), respectively, the highest residue levels reported to date. The estimated 2,3,7,8-TCDD toxic equivalents of non-, mono- and di-ortho PCB congeners in striped dolphins were several times higher than those observed for other marine mammals and humans. Mono-ortho congeners contributed greater 2,3,7,8-TCDD toxic equivalents than non-ortho members. The higher ratio of 3,3′,4,4′,5,5′-H6CB/3,3′,4,4′,5-P5CB (IUPAC 169/126) suggested a strong induction of mixed function oxidase enzymes and highlighted the possibility of using this ratio as an index for risk assessment of PCB contamination in marine mammals. Elevated concentrations of PCBs may have played a role in the immune depression in striped dolphins, ultimately leading to the development of morbillivirus disease.

Journal of proteomics, Jan 15, 2015

Endometriosis, ectopic growth of the uterine lining (endometrium), which affects 6-11% of reprodu... more Endometriosis, ectopic growth of the uterine lining (endometrium), which affects 6-11% of reproductive age women, is associated with pelvic pain and infertility. We investigated the peritoneal fluid (PF), urine and omental fat (OF) proteomes of women with endometriosis vs. individuals with no surgically visualized endometriosis. All participants were enrolled in the NICHD-funded ENDO Study. A two-step proteomic study was performed. The first, a broad survey, employed a semi-quantitative gel LC-mass spectrometry (MS) workflow: SDS PAGE fractionation, trypsin digestion and LC-MS/MS. The results showed sample integrity but failed to detect any differences between women with and without endometriosis. The second step was a quantitative analysis of OF samples. We employed another sample set (n=30) from women ± disease and isobaric mass-tag (iTRAQ) chemistry to label peptides and 2D LC-MS/MS for protein identification and quantification. Three proteins-matrix metalloproteinase-9, neutroph...

Ecotoxicology and Environmental Safety, 2015

PloS one, 2015

Endocrine-disrupting chemicals (EDCs) adversely affect human health. Our objective was to determi... more Endocrine-disrupting chemicals (EDCs) adversely affect human health. Our objective was to determine the association of EDC exposure with earlier age of menopause. Cross-sectional survey using National Health and Nutrition Examination Survey (NHANES) data from 1999 to 2008 (n = 31,575 females). Eligible participants included: menopausal women >30 years of age; not currently pregnant, breastfeeding, using hormonal contraception; no history of bilateral oophorectomy or hysterectomy. Exposures, defined by serum lipid and urine creatinine-adjusted measures of EDCs, data were analyzed: > 90th percentile of the EDC distribution among all women, log-transformed EDC level, and decile of EDC level. Multi linear regression models considered complex survey design characteristics and adjusted for age, race/ethnicity, smoking, body mass index. EDCs were stratified into long (>1 year), short, and unknown half-lives; principle analyses were performed on those with long half-lives as well a...

Since the 1970s, the brominated flame retardants (BFRs), polybrominated diphenyl ethers (PBDEs), ... more Since the 1970s, the brominated flame retardants (BFRs), polybrominated diphenyl ethers (PBDEs), hexabromocyclododecanes (HBCDs), and tetrabromobisphenol A (TBBPA) have been used as additive or reactive flame retardants (FRs) in household products including foam furniture, baby products, mattresses, textiles, electronics, food packaging, and housing insulation to meet flammability standards. Many of these chemicals are now recognized as global contaminants and are associated with adverse health effects including endocrine disruption, reproductive toxicity, developmental neurotoxicity, and cancer. Additive BFRs migrate out of products and accumulate in dust of indoor environments. Dust ingestion is the primary route of human exposure to BFRs, and studies link body burdens of adults and children to indoor dust concentrations. Because of health concerns, PentaBDE and OctaBDE mixtures were phased out of production in 2005, and DecaBDE and HBCDs are scheduled for global elimination by 20...

Ecotoxicology and Environmental Safety

It is well known that perfluorooctane sulfonate (PFOS) preferentially accumulates in the plasma o... more It is well known that perfluorooctane sulfonate (PFOS) preferentially accumulates in the plasma of wildlife and humans. Although earlier studies have suggested that this was due to binding of PFOS to a plasma protein, definite characterization of the protein in in vivo exposure studies was not conducted thus far. In this study, we conducted both in vitro and in vivo experiments to identify PFOS binding protein in the plasma of fish. For the in vivo studies, PFOS was administered intraperitoneally to tiger pufferfish, Takifugu rubripes, and the plasma was separated by ammonium sulfate fractionation. High concentrations of PFOS were found in the 65-70 percent ammonium sulfate fraction (190ng/mL). After SDS-PAGE and N-terminal amino acid sequence analysis, the PFOS-binding protein was identified as an apolipoprotein A-I, which was confirmed on the basis of a significant correlation to the PFOS concentration in each fraction. The plasma samples fractionated by ammonium sulfate from untr...

The Science of the total environment, Jan 27, 2015

Urban areas are sources of perfluoroalkyl substances (PFASs) in the environment, although little ... more Urban areas are sources of perfluoroalkyl substances (PFASs) in the environment, although little is known about specific point sources and distribution of PFASs. Sentinel species, like bottlenose dolphins, are important indicators of environmental perturbations. The high PFAS levels found in dolphins inhabiting Charleston, South Carolina prompted investigation of these chemicals in this area. This study provides further evidence on the extent of contamination and potential sources of PFASs. In this study, concentrations of 11 PFASs measured in estuarine sediments collected in 2012 from the Charleston Harbor and the Ashley and Cooper Rivers (n=36) in South Carolina revealed higher levels than those reported in any other U.S. urban areas. Detectable levels were found in all sample locations with mean total PFAS concentrations of 3.79ngg(-1) (range 0.22 to 19.2ngg(-1) d.w.). Dominant compounds were perfluorooctane sulfonate (PFOS) (mean 1.52ngg(-1); range 0.09-7.37ngg(-1) d.w.), follow...

Environmental research, Jan 26, 2015

Charleston Harbor has elevated concentrations of PFAS in dolphins, but local human exposure data ... more Charleston Harbor has elevated concentrations of PFAS in dolphins, but local human exposure data are limited. We sought to describe PFAS serum concentrations' temporal trends among Gullah African American residents of coastal South Carolina. Longitudinal measures of PFAS in blood serum from a Gullah clinical sample, without lupus, were examined using spaghetti plots and visit-to-visit change scores (e.g., differences in concentrations between visits) among the 68 participants with repeated measures available. We also modeled population-level trends among the 71 participants with any data using proportionate percentile models, accounting for clustering through robust standard errors. In a post-hoc analysis we examined heterogeneity of temporal trends by age through mixed-effects models for the log-transformed PFAS compounds. Population concentrations of PFOS dropped approximately 9 (95% CI: 8, 10) percent each year over 2003-2013. This was concordant with individual PFOS trajecto...

Environment International, 2015

Reproductive toxicology (Elmsford, N.Y.), Jan 11, 2014

Bisphenol A (BPA), a high-production volume industrial chemical found in several consumer product... more Bisphenol A (BPA), a high-production volume industrial chemical found in several consumer products, has been negatively associated with sperm quality. This study aimed to estimate the association between BPA and 35 measures of semen quality among reproductive aged men recruited from 16 counties in Michigan and Texas, 2005-2009. Of 501 enrolled males, 418 (83.4%) provided a urine sample and at least one semen sample. Linear and logistic regression models assessed the association between urinary BPA levels and individual semen quality endpoints. Generalized estimating equations were used to account for repeated measures of semen quality and adjusted models accounted for 11 a priori covariates. Geometric mean total urinary BPA concentration among participants was 0.55ng/mL (95% CI 0.49-0.63). A negative relation between BPA and DNA fragmentation was the sole significant finding in adjusted linear regression (β=-0.0544, p=0.035) and suggestive of less sperm DNA damage.

Concentrations of PCBs (including non‐ortho coplanar congeners), DDTs, HCHs, HCB, aldrin, dieldri... more Concentrations of PCBs (including non‐ortho coplanar congeners), DDTs, HCHs, HCB, aldrin, dieldrin, heptachlor, heptachlor epoxide and chlordanes were determined in river dolphins from the Ganges, India. Residue levels of DDTs were the highest followed by PCBs and HCHs. Noticeable amounts of toxic non‐ortho coplanar PCBs were also detected in the blubber. A continuing exposure of the Ganges biota to organochlorine