Papers by KARLA DAYANARA COBO POZO
Bulletin of environmental contamination and toxicology, Jan 29, 2018
DDT isomers were detected in all the liver and muscle samples of Greenland sharks Somniosus micro... more DDT isomers were detected in all the liver and muscle samples of Greenland sharks Somniosus microcephalus (n = 15) caught in Greenland seawaters. The mean concentrations of ΣDDTs (sum of o,p' and p,p' DDT, DDD, and DDE isomers) were 1094 ± 818 ng/g lipid weight (lw) in the muscle and 761 ± 416 ng/g lw in the liver. The p,p'-DDE accounted for 48% ± 41% and 53% ± 54% of the total DDT residue in the white muscle and liver, respectively. The lipid content was 48% ± 10% in the muscle and 43% ± 17% in the liver. Female sharks showed the highest concentrations of ΣDDTs. The youngest shark showed higher concentrations of ΣDDTs in the liver than the older sharks. To our knowledge, this is one of the few investigations on DDT levels in S. microcephalus where concentrations were correlated to lipid content and sex/size.
Marine pollution bulletin, 2018
The Gulf of Follonica (Italy) is impacted by the chemical pollution from ancient mining activity ... more The Gulf of Follonica (Italy) is impacted by the chemical pollution from ancient mining activity and present industrial processes. This study was aimed to determine the bioavailability of dioxin-like compounds (DLCs) in coastal marine environment and to assess the genotoxic potential of waste waters entering the sea from an industrial canal. Moderately high levels of DCLs compounds (∑ PCDDs + PCDFs 2.18–29.00 pg/g dry wt) were detected in Mytilus galloprovincialis transplanted near the waste waters canal and their corresponding Toxic Equivalents (TEQs) calculated. In situ exposed mussels did not show any genotoxic effect (by Comet and Micronucleus assay). Otherwise, laboratory exposure to canal waters exhibited a reduced genomic template stability (by RAPD-PCR assay) but not DNA or chromosomal damage. Our data reveal the need to focus on the levels and distribution of DLCs in edible species from the study area considering their potential transfer to humans through the consumption of...
The Science of the total environment, 2017
PCBs and PBDEs (7 and 10 congeners, respectively) were analyzed in four coastal surface sediments... more PCBs and PBDEs (7 and 10 congeners, respectively) were analyzed in four coastal surface sediments collected from the northern shore of Bahía Blanca estuary and in nine soils from different locations of Bahía Blanca city and the surrounding region (Southwest of Buenos Aires Province, Argentina). Sediment samples showed PCBs(Σ7) concentrations ranged from 0.61 to 17.6ngg(-1) (dry weight=dw) and PBDEs(Σ10) from 0.16 to 2.02ngg(-1) dw, whereas in soil samples ranged from 0.04 to 1.67ngg(-1) dw for PCBs(Σ7) and 0.04 to 10.7ngg(-1) dw for PBDEs(Σ10). The highest concentrations of both chemicals were detected in the urban and industrial/port areas showing a dominance of the higher chlorinated PCB congeners: in sediments for PCB-180 (56±33%) and PCB-153 (11±6%); and in soils for PCB-138 (23±3%), PCB-153 (22±2%) and PCB-180 (18±7%). In contrast, lower chlorinated PCB congeners were predominant at more distant sites; in sediments for congeners PCB-28 (33±4%) and PCB-52 (14.5±0.2%); and in soi...
Marine Pollution Bulletin, 2017
Growth of the aquaculture industry has triggered the need for research into the potential environ... more Growth of the aquaculture industry has triggered the need for research into the potential environmental impact of chemicals used by salmon farms to control diseases. In this study, the antiparasitic pesticides emamectin benzoate (EB), diflubenzuron (DI), teflubenzuron (TE), and cypermethrin (CP) were measured in sediments near salmon cages in southern Chile. Concentrations for EB were between 2.2 and 14.6 ng g −1 , while the benzoylphenyl ureas DI and TE were detected in the ranges of 0.1 to 1.2 ng g −1 and 0.8 to 123.3 ng g −1 , respectively. These results were similar to data reported for the Northern Hemisphere. On the other hand, the pyrethroid CP was detected in higher concentrations, ranging from 18.0 to 1323.7 ng g −1. According to reported toxicity data, this range represents a potential risk for benthic invertebrates. This report is the first baseline attempt at assessing antiparasitic pesticide levels in the Chilean Patagonia.
Atmospheric Pollution Research, 2016
A preliminary evaluation of Semivolatile Organic Compounds (SVOCs) was performed in the atmospher... more A preliminary evaluation of Semivolatile Organic Compounds (SVOCs) was performed in the atmosphere of Santiago de Cali, Colombia, using passive air samplers based polyurethane foam (PAS-PUF) disks. PAS-PUF were deployed in four sites, along a north-south transect(~15 km), during one sampling period of~4 months in 2011, form the industrial area of Yumbo (EF site) to the agricultural area of Valle del Cauca (FCNE). Results showed, for PCBs and PAHs, a clear north-south (IN > AG) decreasing concentration gradient (~3 times) while OCPs exhibited an opposite gradient (UR < AG). Endosulfan I showed the highest concentrations in air (~0.8e60 ng m À3). The HCHs (a-and g-) concentrations ranged from BDL tõ 19 ng m À3 , with a-HCH showing the highest levels (suggesting recent use of technical HCHs) and for DDTs levels fluctuated from BDL to~29 ng m À3 (with p,p'-DDE accounting for 50e80% of total DDTs). PAHs levels (~25e66 ng m À3) were characterized by the abundance of Phenanthrene (34%), fluoranthene (18%) and pyrene (16%). For PCBs, concentrations in air ranged from~0.2 to 0.9 ng m À3 and were characterized by middle to a higher molecular weight PCB composition pattern. The results of OCPs are much higher than those found in other areas of Latin America. These results are likely influenced by the proximity of agricultural cultivations (i.e., sugarcane crops) in the southern part of the city. These results provide preliminary information about the presence of SVOCs in the atmosphere of Santiago de Cali, and constitute the basis for future monitoring programs.
Environmental science and pollution research international, Jan 31, 2016
In this study, PUF disk passive air samplers were deployed at eight sites, during two sampling pe... more In this study, PUF disk passive air samplers were deployed at eight sites, during two sampling periods, on the Island of Sicily in the Mediterranean basin. Samples were screened for a number of persistent organic pollutants (POPs) including polychlorinated biphenyls (PCBs) (n = 28 congeners), organochlorine pesticides (OCPs) (n = 16 compounds), and polybrominated biphenyl ethers (PBDEs n = 28) using GC-MS. PCB concentrations in air ranged ~10-300 pg m(-3). The PCB pattern was dominated by lower to middle molecular weight PCBs (Cl3-5) and PCB-28 and PCB-52 were the most abundant congeners. α- and γ-Hexachlorocyclohexanes (HCHs) concentrations in air were relatively high ~420 ± 320 (50-1000) and 460 ± 340 (30-1000) pg m(-3), respectively, with an average α/γ ratio of 1 ± 0.5, indicating a tendency of higher use of lindane than of technical HCH. Among DDTs, only p,p'-DDT 90 ± 15 (~10-800) and p,p'-DDE 60 ± 60 (20-400) were frequently detected. DDT/DDE = 0.4-3.0 (1.0 ± 0.7 for b...
Science of The Total Environment, 2016
A discussion is presented on the limitations for air monitoring studies around the Group of Latin... more A discussion is presented on the limitations for air monitoring studies around the Group of Latin American and Caribbean Countries (GRULAC), highlighting key issues requiring further attention, and reports on how a special initiative is addressing these limitations. Preliminary results are presented for the first reported data on organophosphorus flame retardant (OPFR) concentrations in outdoor air from the GRULAC region. At the majority of sites the concentrations and the profile of the OPFRs detected were similar with tris (chloroisopropyl) phosphate (TCPP) dominating (b MDL to 1280 pg/m 3). However, the urban location at Concepción, Chile presented higher Science of the Total Environment xxx (2016) xxx-xxx
Atmospheric Pollution Research, 2016
Little is known regarding the use and ambient levels of pesticides in Chilean agricultural region... more Little is known regarding the use and ambient levels of pesticides in Chilean agricultural regions. Chlorpyrifos (CPF) is one of the most used active ingredients in Chile and in the world. However, few investigations have been conducted to understand its environmental distribution and fate. In this study, PUF disk passive air samples were deployed during~one year in two areas, Angol (5 sites) and Villarrica (2 sites), in the Araucanía Region. The concentration in air of CPF ranged from ten to thousands of pg m À3 (~20e14 600). The highest CPF concentrations were detected at the Angol sites (~14 600 pg m 3) during period 2 (AugusteDecember 2008). These results were higher by a factor of~10e15 than those detected in Villarica sites (~2000 pg m 3) in period 1 (AprileJuly 2008). Seasonal CPF variations were observed, at both sites, within the sampling periods. Air back trajectory analyses showed that air masses from nearby agricultural zones contributed most of the CPF detected in Angol sites when the wind speed was low and at Villarrica when those sources were likely located north of the VMA site. These results provide initial data for CPF in the Chilean atmosphere and contribute new information to understanding distribution of CPF in Chilean environments.
Environmental Pollution, 2016
A retrospective analysis was conducted on air samples that were collected in 2005 under the Globa... more A retrospective analysis was conducted on air samples that were collected in 2005 under the Global Atmospheric Passive Sampling (GAPS) Network around the time period when the Stockholm Convention on Persistent Organic Pollutants came into force. Results are presented for several new flame retardants, including hexabromocyclododecane (HBCD), which was recently listed under the Convention (2013). These results represent the first global-scale distributions in air for these compounds. The targeted compounds are shown to have unique global distributions in air, which highlights the challenges in understanding the sources and environmental fate of each chemical, and ultimately in their assessments as persistent organic pollutants. The study also demonstrates the feasibility of using the PUF disk passive air sampler to study these new flame retardants in air, many of which exist entirely in the particle-phase as demonstrated in this study using a K OA-based partitioning model.
Environmental Pollution, 2016
The occurrence of POPs in remote areas, such as Antarctica, is the result of their ability to ude... more The occurrence of POPs in remote areas, such as Antarctica, is the result of their ability to udergo Long Range Transport (LRT) in the atmosphere, precipitation and cold condensation. In this study, both recent levels of various POPs in Trematomus bernacchii and their changes in roughly three decades were determined in order to evaluate trends of POPs in Antarctic benthic seawaters. In fact, Trematomus bernacchii is considered a good sentinel bio-indicator for monitoring not only the extent of contamination by POPs in the Antarctic aquatic ecosystem, but also changes in Antarctic ecosystem quality and trends. A slight decreasing PCB trend was detected during 30-years time span (from early 1980's to 2010) in the circumantarctic seawaters. Two higher peaks of concentrations were reported in 2001 and 2005 in the Ross Sea and they may reflect the ice melting of icebergs. Because fire risk is very high in Antarctica due to the very dry air, a large use of flame retardants in buildings and furniture of stations is highly probable; moreover, many stations were built when there were no restrictions on flame retardants use. The PBDE levels in the T. bernacchii from 2001 to 2011 ranged 0.05e0.35 pg/g and were of the same order of magnitude in 2001/2011 and in 2002/2005, with a maximum value in 2005 (0.35 pg/g). Comparable concentrations of HCB, HCHs PCDDs and PCDFs are available only for few seasons: all these compounds showed a decreasing temporal trends and their concentrations were one or more order of magnitude lower in 2000se2010s.
La utilización de compuestos químicos como antiparasitarios y antibióticos han sido ampliamente r... more La utilización de compuestos químicos como antiparasitarios y antibióticos han sido ampliamente requerida por la industria del salmón, con el propósito de tratar, prevenir y mitigar enfermedades que afectan negativamente su productividad Figura 1. Pasos de evaluación de riesgo según Van Leeuwen y Hermens (1995) (Van der Oost et al., 2003). El evaluar el riesgo ambiental (ERA, Figura 1) en la industria implica poder plantearse ciertos procesos que midan aquellas magnitudes y probabilidades que afecten adversamente el ecosistema por este tipo de sustancias. Para ello, es necesario plantearse etapas que contribuyan al objetivo de evaluación, los cuales son definidos de la siguiente manera: Identificación del peligro Es la identificación de los efectos adversos, el cual puede ser causado por ciertas sustancias químicas. Evaluación de exposición Es la estimación de las concentraciones en los compartimentos medio ambientales de los compuestos químicos utilizados con fines antiparasitarios...
Environmental Science & Technology, 2014
With current science and policy needs, more attention is being given to expanding and improving a... more With current science and policy needs, more attention is being given to expanding and improving air sampling of semivolatile organic contaminants (SVOCs). However, a wide range of techniques and configurations are currently used (active and passive samplers, different deployment times, different sorbents, etc.) and as the SVOC community looks to assess air measurements on a global scale, questions of comparability arise. We review current air sampling techniques, with a focus on sampling artifacts that can lead to uncertainties or biases in reported concentrations, in particular breakthrough, degradation, meteorological influences, and assumptions regarding passive sampling. From this assessment, we estimate the bias introduced for SVOC concentrations from all factors. Due to the effects of breakthrough, degradation, particle fractions and sampler uptake periods, some current passive and active sampler configurations may underestimate certain SVOCs by 30−95%. We then recommend future study design, appropriateness of sampler types for different study goals, and finally, how the SVOC community should move forward in both research and monitoring to best achieve comparability and consistency in air measurements.
Environmental Science & Technology Letters, 2014
The passive dry deposition (Pas-DD) collector is presented as a tool for estimating atmospheric l... more The passive dry deposition (Pas-DD) collector is presented as a tool for estimating atmospheric loadings (dry deposition fluxes or maps) for polycyclic aromatic hydrocarbons (PAHs) and other semivolatile compounds. Pas-DD collectors based on a parallel plate design were codeployed with conventional polyurethane foam (PUF) disk passive air samplers (PAS) in outdoor urban air over different seasons. Two configurations of sampling media (PUF only vs stacked glass fiber filter on PUF) were used. For both samplers, a higher level of accumulation of PAHs was observed when only the PUF disk was used as the sampling medium. The Pas-DD collector and the PAS accumulated gas-phase PAHs (dry gaseous deposition component) to a similar extent. For the higher-molecular weight PAHs that are associated with particles, the Pas-DD collector was enriched relative to the PAS. Dry deposition velocities derived from the Pas-DD collector were approximately 0.16 cm/s for gas-phase PAHs and up to 0.8 cm/s for particle-phase PAHs.
Atmospheric Pollution Research, 2014
Passive air samplers consisting of polyurethane foam (PUF) disks were deployed in a network of ei... more Passive air samplers consisting of polyurethane foam (PUF) disks were deployed in a network of eight sites across agricultural and urban areas in the Province of Buenos Aires in Argentina to assess levels of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) during two sampling periods in 2006 and 2007. Concentrations (pg m-3) of PCBs in air ranged from BDL to 360, with an average at urban sites of Bahia Blanca (200±130) about one order of magnitude higher than at agricultural sites in the Province of Buenos Aires (20±20). Endosulfan exhibited the highest concentrations of all the chemicals investigated with a maximum of 16 000 pg m-3 in the agricultural area. The remaining OCPs had lower levels (pg m-3) in the following ranges: HCH (-+-hexachlorocyclohexane) from 1 to 50, HEPT (heptachlor) and HEPX (heptachlor epoxide) from BDL to 20, chlordanes (trans-chlordane, cis-chlordane and trans-nonachlor) from 1 to 40, dieldrin from BDL to 30, and p,p´-DDE (the only isomer of DDT that was detected) from BDL to 20. Concentrations of OCPs in air were highest at Bahia Blanca city and generally higher during the warmer sampling period. This study is one of the first investigations of the POPs composition in ambient air in the Province Buenos Aires of Argentina. The results support the Global Monitoring Plan of the Stockholm Convention on POPs and specifically, the need for air data to contribute to the regional report of the GRULAC (GRoUp of Latin American and Caribbean countries) region.
Revista chilena de historia natural, 2000
Marine Pollution Bulletin, 2011
Marine Pollution Bulletin, 2009
Boletín de la Sociedad Chilena de Química, 2001
Los plaguicidas identificados en los sedimentos fueron: a-HCH, g-HCH, Heptacloro, Aldrin, Endrin,... more Los plaguicidas identificados en los sedimentos fueron: a-HCH, g-HCH, Heptacloro, Aldrin, Endrin, pp´-DDT, pp&amp;amp;amp;#x27;-DDE y pp&amp;amp;amp;#x27;-DDD. Los resultados indican variaciones en la distribución y concentración de los COPs, al comparar los lagos urbanos con los lagos prístinos. ...
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Papers by KARLA DAYANARA COBO POZO