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Öğe Bioaccumulation and biomagnification of potential toxic elements (PTEs): An Avicennia germinans-Uca rapax trophic transfer story from Jobos Bay, Puerto Rico(Elsevier, 2021) Martinez-Colon, Michael; Alegria, Henry; Huber, Ashley; Gül, Hatice Kübra; Kurt Karakuş, Perihan BinnurIn southern Puerto Rico along the coastline bordering the Jobos Bay National Estuarine Research Reserve, environmental encroachment has exposed mangrove forest to different sources of pollution. Potentially toxic element concentrations from the F1(Tess) (exchangeable), F4(Tess) (oxidizable), mangrove leaf litter (MLL), and fiddler crab whole body soft tissue were analyzed to assess the fate and transport of pollutants from the environment and its transition into flora-fauna via trophic transfer. Geo-accumulation factor values suggest the bay has experienced limited to no pollution when combining the concentrations of potentially toxic elements extracted from the F1(Tess) and F4(Tess) sediment fractions. These geochemical sedimentary compartments are considered "bioavailable" to flora-fauna as evidenced by the bioaccumulated Cd-Ba-V-Cu-Zn-As-Se in the leaf litter of the black mangrove Avicennia germinans and in the fiddler crab Uca rapax. The biota-sediment accumulation factor (F1(Tess) + F4(Tess)) demonstrated that Uca rapax behave like a de-concentrator for most pollutants and as a macro-concentrator for Cu-As, while the bioconcentration factors identified only Cu-As-Se as being actively bioaccumulated in the fiddler crabs. Of all the potentially toxic elements studied, As is the only one to be biomagnified via sediment-Avicennia germinans leaf litter-Uca rapax food chain. An unexpected find of this study was that the excavated sediment "pellets" by Uca rapax contained up to 4x the concentrations of Cd-Ba-V-Cr-Co-Ni-Cu-Zn-As-Se when compared to the F1(Tess) sediment fraction from the surface, thus suggesting a variable redox boundary within the fiddler crab's burrow.Öğe Historical sediment record and levels of PCBs in sediments and mangroves of Jobos Bay, Puerto Rico(Elsevier, 2016) Alegria, Henry; Martinez-Colon, Michael; Birgül, Aşkın; Brooks, Gregg; Hanson, Lindsey; Kurt Karakuş, Perihan BinnurPolychlorinated biphenyls (PCBs) were quantified in 18 surface sediment samples, 1 sediment core, and several mangrove tissue samples collected in Jobos Bay, Puerto Rico in September 2013. Total PCBs in surface sediments ranged from 0.42 to 1232 ng g(-1) dw. Generally, higher levels were observed near-shore close to urban and industrial areas. The levels suggest significant pollution in Jobos Bay with respect to PCBs. Two-thirds of the sites were dominated by lighter PCB congeners (tri- to penta-chlorinated PCBs) while one-third had heavy PCB congeners (heka- to octa-chlorinated PCBs) dominant. Total PCBs in a sediment core indicated levels fluctuating according to historical usage patterns. Total PCBs were measured in mangal leaves (14-747 ng g(-1) dw), roots (0:26120 ng g(-1) dw), and seeds (16-93 ng g(-1) dw), suggesting bioaccumulation from sediments. This is the first report of a historical profile of PCBs in the study area and of PCB bioaccuinulation in mangroves. This article provides new and, useful information on PCBs in the Caribbean area of the GRULAC region. (C) 2016 Elsevier B.V. All rights reserved.Öğe Organophosphate ester (OPEs) flame retardants and plasticizers in air and soil from a highly industrialized city in Turkey(Elsevier Science Bv, 2018) Kurt Karakuş, Perihan Binnur; Alegria, Henry; Birgül, Aşkın; Gungormus, Elif; Jantunen, LiisaPassive air samples were collected at eight sites in Bursa, Turkey during five sampling periods between February-December 2014. Locations encompassed urban, suburban, industrial, rural and background environments. Soil samples (n = 8) were collected at each site during February 2014. Six OPEs were detected in samples: tris(2-chloroethyl) phosphate (TCEP), tris(chloropropyl) phosphate (TCPP), triphenyl phosphate (TPHP), tris(2-butoxyethyl) phosphate (TBOEP), tris(2-ethylhexyl) phosphate (TEHP), and tris(2-isopropylphenyl) phosphate (T2-iPPP). Frequency of detection in air samples was TCPP and TPHP (100%) > TBOEP (88%) > TCEP (85%) > TEHP (78%) > T2iPPP (20%). Total OPEs in air per site by sampling period (excluding non-detects) ranged from 529 to 19,139 pg/m(3). In soil, total OPEs ranged from 38 to 468 ng/g dw. In air, alkylated OPEs dominated followed by halogenated and aryl OPEs. In air, annual mean concentrations were TBOEP > TCPP > TPHP > T2iPPP > TEHP > TCEP. In soils, alkylated OPEs were dominant at six sites and chlorinated OPEs at two sites. A comparison of OPE profiles between air and soil suggests that soils may be partly a source of OPEs to air. Mean concentrations in air were not directly proportional to temperature, and there were differences between alkylated compared to halogenated and aryl OPEs. In air, total and alkylated OPEs levels were fairly uniform, whereas more variability was found for the halogenated and aryl compounds. The relative contribution to total OPEs decreases for alkylated OPEs and increases for halogenated OPEs in samples going from background to suburban to urban and industrial sites. Levels of individual OPEs were all positively correlated between air and soils. In air, correlations between individual compounds were weak to moderate and were only statistically significant for TBOEP and TPHP. In soils, correlations were generally stronger and statistically significant only for TPHP and T2iPPP. (C) 2017 Elsevier B.V. All rights reserved.Öğe Polybrominated diphenyl ethers (PBDEs) and alternative ?ame retardants (NFRs) in indoor and outdoor air and indoor dust from Istanbul-Turkey: Levels and an assessment of human exposure(2017) Kurt Karakuş, Perihan Binnur; Alegria, Henry; Jantunen, Liisa; Birgül, Aşkın; Topcu, Aslinur; Jones, Kevin C.; Turgut, CaferLevels of polybrominated diphenyl ethers (PBDEs) and novel brominated ?ame retardants (NFRs) were measured in ambient outdoor air, indoor air and indoor dust collected in homes and of?ces at urban, semi-urban and rural locations in Istanbul, Turkey. Indoor air levels of S12PBDEs in homes and of?ces ranged from 36 to 730 pg/m3 and 160 to 10 100 pg/m3, respectively, while levels of S12NFRs ranged from 180 to 7600 pg/m3 and 180 to 42 400 pg/m3, respectively. Outdoor air levels ranged from 110 to 620 pg/ m3 for S12PBDEs and 750 to 2800 pg/m3 for S12NFRs. I/O ratios that are greater than 1 suggest that air concentrations detected in indoor environments are mainly from indoor sources. Indoor dust levels in homes and of?ces of S12PBDEs ranged from 400 to 12 500 ng/g and 330 to 32 200 ng/g respectively and levels of S12NFRs ranged from 320 to 31 400 ng/g and 910 to 97 900 ng/g, respectively. The I/O ratios >1 for PBDEs and NFRs may indicate that emissions of these chemicals detected in homes and of?ces are mainly from indoor sources. Due to childrens' frequent hand-to-mouth behaviour, lower body weight and increased dust ingestion rate compared to adults, exposure rates to target chemicals for children were greater than those of adults. Based on median concentrations of chemicals of interest in dust and air samples from Istanbul, we estimate that exposure rates of children to PBDEs and NFRs are up to 160 times higher compared to adults but none of the estimated exposure rates results for children or adults were than the recommended daily oral reference dose values of certain analytes.Öğe Polyurethane foam (PUF) disk passive samplers derived polychlorinated biphenyls (PCBs) concentrations in the ambient air of Bursa-Turkey: Spatial and temporal variations and health risk assessment(Pergamon-Elsevier Science Ltd, 2017) Birgül, Aşkın; Kurt Karakuş, Perihan Binnur; Alegria, Henry; Gungormus, Elif; Celik, Halil; Cicek, TugbaPolyurethane foam (PUF) passive samplers were employed to assess air concentrations of polychlorinated biphenyls (PCBs) in background, agricultural, semi-urban, urban and industrial sites in Bursa, Turkey. Samplers were deployed for approximately 2-month periods from February to December 2014 in five sampling campaign. Results showed a clear rural-agricultural-semi-urban-urban-industrial PCBs concentration gradient. Considering all sampling periods, ambient air concentrations of Sigma(43)PCBs ranged from 9.6 to 1240 pg/m(3) at all sites with an average of 24.1 +/- 8.2, 43.8 +/- 24.4, 140 +/- 190, 42.8 +/- 24.6, 160 +/- 280, 84.1 +/- 105, 170 +/- 150 and 280 +/- 540 pg/m(3) for Mount Uludag, Uludag University Campus, Camlica, Bursa Technical University Osmangazi Campus, Hamitler, Agakoy, Kestel Organised Industrial District and Demirtas Organised Industrial District sampling sites, respectively. The ambient air PCB concentrations increased along a gradient from background to industrial areas by a factor of 1.7-11.4.4-Cl PCBs (31.50-81.60%) was the most dominant homologue group at all sampling sites followed by 3-Cl, 7-Cl, 6-Cl and 5-Cl homologue groups. Sampling locations and potential sources grouped in principal component analysis. Results of PCA plots highlighted a large variability of the PCB mixture in air, hence possible related sources, in Bursa area. Calculated inhalation risk levels in this study indicated no serious adverse health effects. This study is one of few efforts to characterize PCB composition in ambient air seasonally and spatially for urban and industrial areas of Turkey by using passive samplers as an alternative sampling method for concurrent monitoring at multiple sites. (C) 2016 Elsevier Ltd. All rights reserved.
