Ecological risk assessment of PCBs and other organic contaminant residues in Laguna de Terminos, Mexico (original) (raw)
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Organochlorine Pesticides and PCBs in a Southern Atlantic Coastal Lagoon Watershed, Argentina
Archives of Environmental Contamination and Toxicology, 2001
There recently have been increasing interest in South America on organic pollutants from the coastal marine environment. This study intended to seek out the occurrence and distribution of persistent organochlorine compounds in the Mar Chiquita coastal lagoon watershed. The levels were measured in sediments and associated crabs. Though a significant number of PCBs (mainly penta-and hexachlorinated congeners) were detected, the concentrations were very low (in the order of ppbs), indicative of an estuarine environment with little industrial development. On the other hand, pesticide residues were higher than PCBs in one or two orders of magnitude, as a result of the important agricultural activities in the area. Heptachlor epoxide, DDT and its metabolites, and ␥-HCH were the predominant OC pesticides in sediments as well as in crabs. Significant differences among geographical areas: Channel 5 and Vivoratá Creek (northern and southern sampling sites, respectively) contained detectable pesticide concentrations (heptachlor epoxide, DDE, DDD, and mirex). Materials and Methods Samples of C. angulatus were obtained from the Mar Chiquita coastal lagoon (Argentina, 37°32Ј to 37°45Ј S, and 57°19Ј to 57°26Ј W) and tributary creeks, during May 1995 and 1996. Samples of sediments were only taken in 1996. Sampling was done at Channel 5, Grande, Sotelo, and Vivoratá Creeks (Figure 1
Chemosphere, 2009
The coastal lagoon sys tem of Laguna de Ter mi nos, Cam pe che, Mex ico, a nat u ral reserve since 1994, was investi gated for con tam i na tion by agri cul tural and indus trial chem i cal res i dues. Water, sed i ment and biota samples were ana lyzed for a wide vari ety of orga no chlo rine and orga no phos pho rus com pounds. Chlor pyri fos was detected in water in con cen tra tions up to 72 pg L ¡1 and, amongst orga no chlo rine com pounds, )PCB were mea sured aver ag ing 1177 pg L ¡1 and )DDT 279 pg L ¡1 . Res i dues of chlo ri nated com pounds were pres ent in sed i ments and in biota with )DDT aver ag ing 190 pg g ¡1 and 5876 pg g ¡1 in sed i ment and oys ters, respec tively.
Environmental Science & Technology, 1995
Livers of bullfrogs (Rana catesbeiana) from a polychlorinated biphenyl (PCB) contaminated watershed and hazardous waste site located in Pickens County, South Carolina, contained signi®cantly higher concentrations of PCBs (2.33 and 2.26 ppm, respectively) than those from a reference site (0.05 ppm). Green frogs (R. clamitans) from the two contaminated sites also accumulated higher levels of PCBs (2.37 and 3.88 ppm, respectively) than those from the reference site (0.02 ppm). No temporal variation was observed in PCB concentrations of bullfrogs or green frogs from the contaminated sites between 1992 and 1993. Levels of PCBs in the livers of northern water snakes (Nerodia sipedon) were signi®cantly higher in snakes from the contaminated watershed (13.70 ppm) than in those from the waste site (2.29 ppm) and two reference sites (2.50 and 1.23 ppm). When compared to frogs, signi®cantly higher bioaccumulation occurred in water snakes from the contaminated watershed. No signi®cant dierences in PCB levels were found with respect to sex or body size (snout±vent length (SVL) or body mass) for frogs or snakes. PCBs were detected also in eggs of both frogs and snakes. Results of this study provide baseline data and document the bioaccumulation of PCB residues in frog and snake tissues; however, the signi®cance of these tissue residues to reproduction, survival, growth/ development, and population dynamics in contaminated habitats is unknown. Ó
Chemosphere, 2008
Organochlorinated compounds, seven indicator PCB congeners, DDT and its main metabolites, were determined in sediment and crab (Chasmagnathus granulata) samples collected from mangrove areas near Rio de Janeiro, Brazil. Samples were analysed according to the FAO/SIDA protocols using continuous non-polar solvent extraction and a conventional GC-ECD apparatus. The highest levels of total PCB congeners and total DDT metabolites in sediments (184.16 and 37.40 ng.g −1 d.w. respectively) and crab eggs (570.62 and 98.22 ng.g −1 d.w. respectively) were found at impacted mangroves. The higher PCB congeners than DDT metabolites levels suggesting a stronger industrial impact in this area. The results indicate that the population density of crab is negatively affected by sediment contamination that is reflected basically by the organochlorine content in the female eggs. The organochlorine concentration in eggs is more significant to evaluate or estimate an impact of these pollutants upon C. granulata population than the organochlorine concentration in sediment samples.
Chemosphere, 2008
Organochlorinated compounds, seven indicator PCB congeners, DDT and its main metabolites, were determined in sediment and crab (Chasmagnathus granulata) samples collected from mangrove areas near Rio de Janeiro, Brazil. Samples were analysed according to the FAO/SIDA protocols using continuous non-polar solvent extraction and a conventional GC-ECD apparatus. The highest levels of total PCB congeners and total DDT metabolites in sediments (184.16 and 37.40 ng.g −1 d.w. respectively) and crab eggs (570.62 and 98.22 ng.g −1 d.w. respectively) were found at impacted mangroves. The higher PCB congeners than DDT metabolites levels suggesting a stronger industrial impact in this area. The results indicate that the population density of crab is negatively affected by sediment contamination that is reflected basically by the organochlorine content in the female eggs. The organochlorine concentration in eggs is more significant to evaluate or estimate an impact of these pollutants upon C. granulata population than the organochlorine concentration in sediment samples.
Environmental Toxicology and Chemistry, 2006
Concentrations of polychlorinated biphenyls (PCBs), organochlorine pesticides, and polycyclic aromatic hydrocarbons (PAHs) were measured in gastropods from the Lagoon of Venice, Italy. The visceral coil and the rest of the soft body of organisms (Hexaplex trunculus) sampled at two stations inside the lagoon and three stations on the seaward side were analyzed to evaluate their contamination levels. Preferential accumulation of PCBs and pesticides in the visceral coil (Ͼ80%) compared with the rest of the soft body was observed, whereas on average, PAHs showed no preferential partitioning. Differences between levels of organochlorine contaminants in the gastropods highlighted a gradient of pollution from the stations inside the lagoon (PCBs, 45-363 ng/g; pesticides, 4-51 ng/g) to the sea (PCBs, 13-131 ng/g; pesticides, 2-29 ng/g). The possible role of the three classes of contaminants, in addition to that of organotin compounds (OTCs), previously analyzed in the same samples, in causing one of the anatomic modifications because of imposex in this gastropod also was studied. A modeling approach by partial least squares (PLS) in latent variables was applied to explain the penis length of imposex-affected females with concentrations of organic pollutants. The synergistic role of PCBs, pesticides, and OTCs was evidenced, whereas the contribution of PAHs appeared to be very low.
Determination of polychlorobiphenyls in Venice Lagoon sediments
Chemosphere, 2001
Polychlorinated biphenyl (PCBs) congeners were measured in 14 sediment samples collected at ®ve sites in the Venice Lagoon selected on the basis of a supposed diversity of inputs and of pollution levels. The PCBs were determined after a sonication assisted extraction by gaschromatography mass spectrometry (GCMS). The sum of the congener concentrations determined in the samples range from 4.05 to 239.15 ng/g on a dry weight basis. The concentration values are very variable both comparing the sites and comparing dierent samples from the same site and can be connected to the sand percentage in the sediment samples. The correlation matrix obtained from data matrix using the congener concentrations as variables shows high values, mostly between 0.964 and 1, suggesting that the pattern of the PCB congeners and the ratios among the concentrations in Venice Lagoon sediments are more or less constant; the samples dier only in the concentration level. Ó
Environmental Science & Technology, 2018
Temporal trends of polychlorinated biphenyls (PCBs) were studied for detritivorous fish (1996−2017) and settling material (2002−2017) from polluted Buenos Aires coast and for a dated sediment core (1970−2013) from the outer Río de la Plata estuary. In spite of contrasting concentrations [5.3 ± 6.3 μg•g −1 dry weight (dw) for fish, 48 ± 26 ng•g −1 dw for settling material, and 1.5 ± 0.7 ng•g −1 dw for core], all three revealed exponentially decreasing trends over time (97%, 83%, and 83%, respectively). Time trends showed peak maxima coincident with Argentina's period of maximum PCB usage in 1973−1980 (80 cm depth in the core) and pulse discharges related to PCB banning in 2001− 2002 (fish) with a lighter signature enriched in less persistent tri-and tetrachlorobiphenyls. The log−linear PCB time trends compare well with the predicted decrease for a high emission scenario from global emission data; the best fit was observed for the less impacted sediment core (−2%•year −1 versus −3%• year −1 for emission scenario). Steeper slopes are observed for the more polluted settling material (−5%•year −1) and especially for fish, in which the background decline trend tripled after the 2001 PCB pulse (from −7%•year −1 to −21%•year −1). These PCB time trends in related environmental compartments from contrasted sites provide rare evidence for evaluating the effectiveness of control measures in southern South America.