Acute and genotoxic effects of Baku Harbor sediment on Russian sturgeon, Acipenser guildensteidti

Health indicators and contaminant levels of a critically endangered species in the Gironde estuary, the European sturgeon

The European sturgeon, Acipenser sturio, is a highly endangered species that almost disappeared in the last decades. Thanks to yearly restocking of the population, this species is still found in the Gironde estuary (France), where juveniles grow during several years before leaving to the ocean. The aims of this study were to evaluate the pressure exerted on these fish by known organic and inorganic contaminants during their stay at the Gironde estuary, and to get information on the fish's health in this context. Monthly captures over the year 2014 provided 87 fish from the cohorts 2012 and 2013 mainly, and from cohorts 2008, 2009, and 2011, all fish born in hatchery. We report the very first analyses of contaminant levels and of biological markers measured in the blood of these fish. Low inorganic contamination was found, composed of seven metals mainly Zn (< 5 μg mL^-1), Fe (< 1.5 μg mL^-1), Cu (< 0.8 μg mL^-1), Se (< 0.8 μg mL^-1), As (< 0.25 μg mL^-1), Co (< 0.14 μg mL^-1), and Mn (< 0.03 μg mL^-1). Concerning persistent organic contaminants, the sum of seven PCBs varied from 1 to 10 ng g^-1 plasma, that of eight OCPs from 0.1 to 1 ng g^-1, and that of eight PBDEs from 10 to 100 pg g^-1. Higher levels of contaminants were measured during spring as compared to summer. The sex steroid hormone plasma levels (estradiol, testosterone, and 11-ketotestosterone) were quite low, which was predictable for juveniles. The transcription of reproduction-involved genes (EstR, AR, LHR, sox9) in blood cells was demonstrated for the first time. Some of them were correlated with organic contaminant levels PCBs and OCPs. Other gene transcriptions (sodCu and bax) were correlated with PCBs and OCPs. However, the DNA damage level measured here as comet tail DNA and micronuclei ratio in red blood cells were in the very low range of the values commonly obtained in fish from pristine areas. The data presented here can serve as a reference base for future monitoring of this population of sturgeons.

Toxic Site Identification Program in Azerbaijan

The need to protect communities from hazardous waste is an important agenda for any nation. Although pollutant management and policy development are attempted in many developing countries, it is not always successful due to limited funds, project resources, and access to trained experts to conduct toxic site identification projects. For this reason, Pure Earth created the Toxic Site Identification Program (TSIP). The goal of the TSIP program is to provide reliable information and data that identifies location of toxic sites and the level of toxic severity. TSIP is significant because it provides developing countries a database of ranked toxic sites identified as hazardous risk to human health. For example, Azerbaijan is one of the most polluted post-Soviet nations, but has limited resources to address and manage its polluted sites. The Azerbaijani TSIP database is the first reliable data source that identifies hazardous pollutants in the country. Our study is significant because it discusses how the TSIP labels and ranks the level of toxic severity to human health. It is also the first data source in Azerbaijan that identifies which Soviet legacy toxic sites are affecting local communities. Although our study is specific to Azerbaijan, the TSIP method can be applied to nations with similar data limitations and the need for a database that identifies country specific environmental and hazardous locations. The data sampling method and results are mapped and accompanied by tables of the collected pollutant types to identify communities at greatest health-risk to legacy toxic sites.

Differential impact of anthropogenic pressures on Caspian Sea ecoregions

Over the past decades, overall ecological conditions in the Caspian Sea have deteriorated. However, a comprehensive understanding of lake-wide spatial differences in anthropogenic pressures is lacking and the biological consequences of human impacts are poorly understood. This paper therefore aims at assessing the individual and combined effects of critical anthropogenic pressures on the Caspian Sea ecoregions. First, cumulative pressure scores were calculated with a cumulative environmental assessment (CEA) analysis. Then, the individual contribution of anthropogenic pressures was quantified. Finally, ecoregion-specific differences were assessed. The analyses show that both cumulative and individual pressure scores are unevenly distributed across the Caspian Sea. The most important individual pressures are invasive species, chemical pollution and poaching. This uneven distribution of pressure scores across Caspian Sea ecoregions creates new challenges for future conservation strategies, as different ecoregions usually require different conservation measures.

An evaluation of germline mutations and reproductive impacts in fathead minnow (Pimephales promelas) exposed to contaminated sediment

Polycyclic aromatic hydrocarbons (PAHs) have become ubiquitous in the aquatic environment. Some PAHs are mutagenic, potentially causing germline mutations in fish that inhabit PAH contaminated waters. We evaluated the effect of exposure to sediment-borne PAHs on reproduction and germline mutation rates in fathead minnows (Pimephales promelas). Exposure to the contaminated sediment had no significant impact on the reproductive endpoints measured in this study. Germline mutations rates at three microsatellite DNA loci were 1.69 × 10^-3 in fish exposed to PAH-contaminated sediment and 0.55 × 10^-3 in control fish, with zero mutations being observed in fish exposed to sediment from a reference site. While the difference in mutation rates between treatments was not statistically significant for the sample size used (15-19 families per treatment), the observed mutations rates enabled us to estimate the sample size required to detect a significant effect. To our knowledge, this is the first report of germline mutation rates in fathead minnow exposed to an environmental contaminant, providing baseline data for use in the design of future experiments.

Micronucleus test on Triturus carnifex as a tool for environmental biomonitoring

The amphibian micronucleus test has been widely used during the last 30 years to test the genotoxic properties of several chemicals and as a tool for ecogenotoxic monitoring. The vast majority of these studies were performed on peripheral blood of urodelan larvae and anuran tadpoles and to a lesser extent adults were also used. In this study, we developed protocols for measuring micronuclei in adult shed skin cells and larval gill cells of the Italian crested newt (Triturus carnifex). Amphibians were collected from ponds in two protected areas in Italy that differed in their radon content. Twenty-three adult newts and 31 larvae were captured from the radon-rich pond, while 20 adults and 27 larvae were taken from the radon-free site. The animals were brought to the laboratory and the micronucleus test was performed on peripheral blood and shed skins taken from the adults and on larval gills. Samples from the radon-rich site showed micronucleus frequencies higher than those from the radon-free site and the difference was statistically significant in gill cells (P < 0.00001). Moreover, the larval gills seem to be more sensitive than the adult tissues. This method represents an easy (and noninvasive in the case of the shed skin) application of the micronucleus assay that can be useful for environmental studies in situ.

The legacy of persistent organic pollutants in Azerbaijan: an assessment of past use and current contamination

Azerbaijan has a history of production and heavy use of organochlorine pesticides (OCPs) with use focused in the main agricultural lowland region centred on the Kur River. Using a number of data sources, including archived reports from several government ministries, we attempt to construct production and use inventories for dichlorodiphenyltrichloroethane (DDT) and HCHs and compare these to scientific estimates of production and use of these chemicals in the 1960s to the 1980s. Notable discrepancies are evident particularly for DDT, with Azeri government records indicating much higher use (147-fold) than that estimated by the international scientific community. Soil and river sediment data from the 1980s and 2000s are also presented. While it is recognised that analytical uncertainties remain high for these older data (generated by GC-ECD), there is some evidence to show a decline in concentrations for some OCPs over this period. Extremely high concentrations of OCPs are evident for soils sampled in the vicinity of obsolete pesticide storage sites (found in numerous locations around the agricultural lowlands) and these levels may pose a health risk to wildlife and humans. River sediment data indicate high levels of both OCPs and polychlorinated biphenyls (PCBs), particularly downstream of the confluence of the two main rivers, the Kur and Araz. Particle-bound annual fluxes from the Kur River into the Caspian Sea are estimated for PCBs and OCPs and these are likely to influence levels observed in local coastal sediments, with agreement between river sediment data generated in the early 2000s and coastal marine sediment data generated from separate studies. We recommend that monitoring efforts should focus on soils in agricultural areas and around pesticide storage and production facilities as these soils will continue to provide a source of POPs to the regional environment.

Organochlorine pesticides and polychlorinated biphenyls in air and soil across Azerbaijan

Concentrations of selected organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) are reported in air and surface soil in an extensive spatial survey across Azerbaijan, a country bordering the Caspian Sea with a history of OCP production and extensive use. Polyurethane foam disc passive air samplers (PAS) were deployed during October-November 2008 with soil samples collected in July 2009. Levels of Σ(7)PCB in ambient air were generally low (mean of 0.046 ng m(-3), n = 13) and comparable to concentrations reported in countries within Eastern Europe and similar to or lower than concentrations reported in urban air in the UK and other western countries. Surprisingly, PCB concentrations in rural/background soil fell below the method detection limits at most sites, although concentrations were 0.209 and 0.071 ng Σ(7)PCB g(-1) dry weight (dw) for two urban sites, again comparable to PCB levels measured at background sites in Europe. Levels of α-HCH, β-HCH, γ-HCH and p,p'-DDT/E were elevated in ambient air across Azerbaijan in comparison to PAS-derived concentrations reported elsewhere, with concentrations of α-HCH in air ranging from 0.085 to 2.699 ng m(-3) and p,p'-DDE, 0.037-2.290 ng m(-3). High concentrations of OCPs occurred at several of the urban sites and at sites in proximity to old pesticide storage facilities with concentrations in soil >0.1 μg g(-1) dw for p,p'-DDE and p,p'-DDT at several sites. The ratio of p,p'-DDT/p,p'-DDE was close to unity in the soil at these sites, but elsewhere, the ratio was <1, indicating a weathered DDT pattern, which was also reflected in the air at all sites. A fugacity approach revealed the strong likelihood of net soil-to-air transfer at the majority of sites for all OCPs. The calculated annual fluxes or loading to the atmosphere from a rural/agricultural area (representing land as vineyards and cotton cultivation) were estimated to be on the order of ≈10-100 kg year(-1) for the HCH isomers (including the β -isomer) and p,p'-DDE. The high levels of OCPs in soils, particularly in the vicinity of obsolete-pesticide storage facilities and at select urban sites are of concern and warrant regular monitoring activities and the development of containment or mitigation strategies.

DNA damage in cichlids from an oil production facility in Guatemala

This study focused on several wetlands in Laguna del Tigre National Park (Guatemala) as part of Conservation International's Rapid Assessment Program. Sediment and water samples were collected from a laguna near Xan field, Guatemala's largest oil facility, and three other sites for determination of levels of polycyclic aromatic hydrocarbons (PAHs). Cichlid fish (Thorichthys meeki and Vieja synspila) were collected for determination of DNA strand breakage (by gel electrophoresis), chromosomal breakage (flow cytometry), and fin erosion. For T. meeki from Xan field, chromosomal breakage and strand breakage was greater than in at least two of the three reference sites. For V. synspila, chromosomal breakage and strand breakage were greater in Xan than one of the two reference sites. Fin erosion was observed only at the Xan laguna. Genetic biomarker effects and fin erosion, along with patterns of aqueous PAH concentrations, indicate that fish are affected by anthropogenic contaminants. PAHs were elevated at some reference sites, but environmental forensic analysis suggested a pyrogenic or diagenic origin. It is possible that oil field brines injected into the ground water caused fin erosion and genotoxicity in fish at Xan field, and it is also possible that pyrogenic PAHs influence levels of DNA damage in reference sites. These analyses represent one of the first efforts to examine genotoxicity in native Mesoamerican cichlids.

Wildlife toxicology: biomarkers of genotoxic exposures at a hazardous waste site

A large number of hazardous waste sites in the United States have undergone the initial stages of remediation or containment. At many of the remaining sites, the potential for exposure to ecological receptors is a primary concern. This manuscript reports on studies to investigate the impact on ecological receptors exposed to complex mixtures at a former creosote facility. Currently there are isolated areas on-site that were not addressed in the initial removal action that appear to be releasing polycyclic aromatic hydrocarbons (PAHs) to the surrounding environment. The U.S. EPA collected environmental samples and performed ex situ sediment bioassays to measure chronic toxicity; whereas, this study describes an in situ study to measure biomarkers of effect in two ecological receptors. Mosquitofish (Gambusia affinis) and cricket frogs (Acris crepitans) were collected from a small intermittent creek adjacent to the site, and reference stations. A weight-of-evidence ecological risk assessment was completed for the amphibian and fish communities. The ecological risk assessment was developed using analysis of media chemistry, body burden of specific PAHs, bioassay results, community surveys, and cellular genome size variation as a biomarker of genotoxicity. Flow cytometric estimates of chromosomal damage were significantly elevated for both mosquitofish and cricket frogs inhabiting the contaminated site, relative to at least one reference site. Surface water screening values for fish and amphibians exceeded screening values for PAHs by more than one order of magnitude in the on-site creek, and sediment PAH concentrations were extremely high (up to 1,549 microg/dry g). Tissue concentrations of PAHs were below screening values. Media chemistry, bioassay and genotoxicity data all support the same conclusion that on-site PAHs continue to impact aquatic receptors. The genotoxicity findings are consistent with and contribute to results of the weight-of-evidence ecological risk assessment. The results support continuing efforts to incorporate biomarkers as valuable lines of evidence within ecological risk assessment.

Evaluation of the genotoxicity of river sediments from industrialized and unaffected areas using a battery of short-term bioassays

The present investigation evaluated the capacity of the Salmonella mutagenicity test, the comet assay, and the micronucleus assay to detect and characterize the genotoxic profile of river sediments. Three stations were selected on an urban river (Bouches du Rhône, France) exposed to various sources of industrial and urban pollution (StA, StB, and StC) and one station on its tributary (StD). One station in a nonurban river was included (REF). The concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) were determined by HPLC, and the genotoxicity of the sediments was monitored by the Salmonella mutagenicity test (TA98 + S9, YG1041 +/- S9), the comet assay, and the micronucleus assay on CHO cells. Chemical analysis showed that the total PAH concentrations ranged from 23 microg kg(-1) dw (REF) to 1285 microg kg(-1) dw (StD). All the sediments were mutagenic in the Salmonella mutagenicity test. The mutagenicity was probably induced by the presence of nitroarenes (StA, StB, StC, and StD) and aromatic amines (REF) as deduced from the mutagenicity profiles of strains YG1041 +/- S9 and TA98 + S9. The comet assay revealed direct DNA lesions in REF, StA, and StB sediments and metabolization-dependent DNA damage in StC and StD. The micronucleus assay showed an absence of clastogenicity for StA +/- S9 and StC-S9, and a significant clastogenicity +/- S9 for the three other stations. The genotoxicity ranking determined by the comet assay + S9 matched the ranking of total and carcinogenic PAH concentrations, and this assay was found to be the most sensitive.

Decrease in activity of the serotoninergic system during mutagenesis

We studied changes in the content of serotonin-modulated anticonsolidation protein in the liver of goldfishes and gobies caused by oil and industrial pollution. The concentration of serotonin-modulated anticonsolidation protein in fish liver increased after short-term exposure to oil-contaminated water (100 mg/liter), but decreased under long-term effect of industrial wastes. We hypothesize that serotonin plays a role in antimutagenic protection of the organism and maintains the differentiated state of mature cells.

Evolutionary toxicology: population-level effects of chronic contaminant exposure on the marsh frogs (Rana ridibunda) of Azerbaijan

We used molecular methods and population genetic analyses to study the effects of chronic contaminant exposure in marsh frogs from Sumgayit, Azerbaijan. Marsh frogs inhabiting wetlands in Sumgayit are exposed to complex mixtures of chemical contaminants, including petroleum products, pesticides, heavy metals, and many other industrial chemicals. Previous results documented elevated estimates of genetic damage in marsh frogs from the two most heavily contaminated sites. Based on mitochondrial DNA (mtDNA) control region sequence data, the Sumgayit region has reduced levels of genetic diversity, likely due to environmental degradation. The Sumgayit region also acts as an ecological sink, with levels of gene flow into the region exceeding gene flow out of the region. Additionally, localized mtDNA heteroplasmy and diversity patterns suggest that one of the most severely contaminated sites in Sumgayit is acting as a source of new mutations resulting from an increased mutation rate. This study provides an integrated method for assessing the cumulative population impacts of chronic contaminant exposure by studying both population genetic and evolutionary effects.

Chromosomal damage in two species of aquatic turtles (Emys orbicularis and Mauremys caspica) inhabiting contaminated sites in Azerbaijan

The Caspian region and specifically the Apsheron peninsula of Azerbaijan are known to be polluted with a variety of environmental contaminants. These complex mixtures of contaminants make risk assessment difficult. We used the flow cytometry method (FCM) and the micronucleus assay (MN) to assess chromosomal damage in aquatic turtles (Emys orbicularis, the European pond turtle; and Mauremys caspica, the Caspian turtle) inhabiting contaminated wetlands in Azerbaijan. Evidence of genetic damage was found for two sites, Neftchala and Sumgayit, relative to a reference site, Ali Bairamly. Sediment samples from each site were analyzed for PAHs and mercury to evaluate potential contaminant associations with genetic damage. A significant positive correlation was documented between three-ring PAH sediment concentrations and FCM estimates of chromosomal damage in E. orbicularis. These data combine to show that the contaminated wetlands in Sumgayit and Neftchala are genotoxic and that three-ring PAHs are likely a significant influence on observed genotoxicity.

The mutagenic hazards of aquatic sediments: a review

Sediments are the sink for particle-sorbed contaminants in aquatic systems and can serve as a reservoir of toxic contaminants that continually threaten the health and viability of aquatic biota. This work is a comprehensive review of published studies that investigated the genotoxicity of sediments in rivers, lakes and marine habitats. The Salmonella mutagenicity test is the most frequently used assay and accounts for 41.1% of the available data. The Salmonella data revealed mutagenic potency values for sediment extracts (in revertants per gram dry weight) that spans over seven orders of magnitude from not detectable to highly potent (10(5) rev/g). Analyses of the Salmonella data (n=510) showed significant differences between rural, urban/industrial, and heavily contaminated (e.g., dump) sites assessed using TA98 and TA100 with S9 activation. Additional analyses showed a significant positive correlation between Salmonella mutagenic potency (TA98 and TA100 with S9) and PAH contamination (r2=0.19-0.68). The second and third most commonly used assays for the analysis of sediments and sediment extracts are the SOS Chromotest (9.2%) and the Mutatox assays (7.8%), respectively. These assays are frequently used for rapid initial screening of collected samples. A variety of other in vitro endpoints employing cultured fish and mammalian cells have been used to investigate sediment genotoxic activity. Endpoints investigated include sister chromatid exchange frequency, micronucleus frequency, chromosome aberration frequency, gene mutation at tk and hprt loci, unscheduled DNA synthesis, DNA adduct frequency, and DNA strand break frequency. More complex in vivo assays have documented a wide range of effects including neoplasms and preneoplastic lesions in fish and invertebrate exposed ex situ. Although costly and time consuming, these assays have provided definitive evidence linking sediment contamination and a variety of genotoxic and carcinogenic effects observed in situ.