Environmental Science and Pollution Research

Drobniewska, Agata; Wójcik, Dorota; Kapłan, Monika; Adomas, Barbara; Piotrowicz-Cieślak, Agnieszka; Nałęcz-Jawecki, Grzegorz

doi: 10.1007/s11356-016-7174-3pmid: 27495922

Sulfonamides are the second most widely used group of veterinary antibiotics which are often detected in the environment. They are eliminated from freshwaters mainly through photochemical degradation. The toxicity of sulfadimethoxine (SDM) was evaluated with the use of Lemna minor before and after 1- and 4-h irradiation in a SunTest CPS+ solar simulator. Eight endpoints consisting of: number and total area of fronds, fresh weight, chlorophylls a and b, carotenoids, activity of catalase and guaiacol peroxidase, and protein content were determined. The total frond area and chlorophyll b content were the most sensitive endpoints with EC50 of 478 and 554 μg  L−1, respectively. The activity of guaiacol peroxidase and catalase increased at SDM concentrations higher than 125 and 500 μg  L−1, respectively. The SDM photodegradation rate for first order kinetics and the half-life were 0.259 h−1 and 2.67  h, respectively. The results show that the toxicity of irradiated solutions was caused by SDM only, and the photoproducts appeared to be either non-toxic or much less toxic to L. minor than the parent compound. To study the recovery potential of L. minor, after 7 days exposure in SDM solutions, the plants were transferred to fresh medium and incubated for the next 7 days. L. minor has the ability to regenerate, but a 7-day recovery phase is not sufficient for it to return to an optimal physiological state.

Manusadžianas, Levonas; Gylytė, Brigita; Grigutytė, Reda; Karitonas, Rolandas; Sadauskas, Kazys; Vitkus, Rimantas; Šiliauskas, Laurynas; Vaičiūnienė, Jūratė

doi: 10.1007/s11356-016-8023-0pmid: 27830416

Blaise, Christian; Gagné, François; Burgeot, Thierry

doi: 10.1007/s11356-016-6908-6pmid: 27230145

While biomarkers are undeniably key tools in aquatic ecotoxicology to measure adverse effects linked to contamination events, their application is often inhibited by monetary constraints negating the possibility of having access to dedicated equipment, special wares, and/or expensive reagents. To offset this bottleneck, we propose three simple physiological biomarkers, quantifiable in bivalves, that are free of cost considerations and that can provide basic knowledge on animal health and water quality. Indeed, condition index (CI), growth index (GI), and SOS response (air-time survival) comprise measurements straightforward enough to perform by any laboratory or science body on the planet. Long-term monitoring or screening studies can be carried out with these biomarkers and they are able to provide robust information notably after exposure of bivalves to either singular or multiple agents of contamination. By highlighting examples of data generated in aquatic studies conducted in Eastern Canada under both laboratory and field situations with different species of marine and freshwater mollusks, we establish the suitability of these biomarkers for assessing environmental contamination. Their relationships with other biomarkers are also shown which further corroborate their value as reliable indicators of ecosystem health.

Kawano, Machi; Uno, Seiichi; Koyama, Jiro; Kokushi, Emiko; McElroy, Anne

doi: 10.1007/s11356-016-6917-5pmid: 27234825

Oxygenated polycyclic aromatic hydrocarbons (oxyPAHs) are directly discharged into the atmosphere with exhaust gas from diesel engine automobiles and industry and are also generated by photo-oxidation and/or microbial metabolism of parent polycyclic aromatic hydrocarbons (PAHs). They are widely distributed in environment, especially around urban areas. We evaluated the effects of exposure to oxyPAHs as acenaphthenequinone (ANQ), 7,12-benz(a)anthracenequinone (BAQ), 1,4-naphthoquinone (NAQ), and 9,10-phenanethrenequinone (PHQ) in Japanese medaka (Oryzias latipes) embryos. ANQ (>2720 μg/L) caused caving in the yolk sac, and BAQ (>22.4 μg/L) caused tanning of the oil droplet. Additionally, NAQ (>314 μg/L) and PHQ (>734 μg/L) stopped development of medaka embryos beginning 2 days after the start of exposure. The hatched larvae from embryos exposed to ANQ, BAQ, NAQ, or PHQ at 518, 9.86, 36.5, or 80.7 μg/L, respectively, exhibited incomplete development of the cephalic region, incomplete palate, unabsorbed and hypertrophied yolk sac, tubular heart, altered axial curvature, and poor swimming ability. These symptoms were similar to those observed in blue sac disease, which is caused by exposure to PAHs.

Kokushi, Emiko; Shintoyo, Aoi; Koyama, Jiro; Uno, Seiichi

doi: 10.1007/s11356-016-6425-7pmid: 27053050

In this study, the metabolic effects of waterborne exposure of medaka (Oryzias latipes) to nominal concentrations of 20 (L group) and 2000 μg/L (H group) 2,4-dichlorophenol (DCP) were examined using a gas chromatography/mass spectroscopy (GC/MS) metabolomics approach. A principal component analysis (PCA) separated the L, H, and control groups along PC1 to explain the toxic effects of DCP at 24 h of exposure. Furthermore, the L and H groups were separated along PC1 at 96 h on the PCA score plots. These results suggest that the effects of DCP depended on exposure concentration and time. Changes in tricarboxylic cycle metabolites suggested that fish exposed to 2,4-DCP require more energy to metabolize and eliminate DCP, particularly at 96 h of exposure. A time-dependent response in the fish exposed to DCP was observed in the GC/MS data, suggesting that the higher DCP concentration had greater effects at 24 h than those observed in response to the lower concentration. In addition, several essential amino acids (arginine, histidine, lysine, isoleucine, leucine, methionine, phenylalanine, threonine, tryptophan, and valine) decreased after DCP exposure in the H group, and starvation condition and high concentration exposure of DCP could consume excess energy from amino acids.

Ye, Roy; Peterson, Drew; Seemann, Frauke; Kitamura, Shin-Ichi; Lee, J.; Lau, Terrance; Tsui, Stephen; Au, Doris

doi: 10.1007/s11356-016-7208-xpmid: 27473621

Many anthropogenic pollutants in coastal marine environments can induce immune impairments in wild fish and reduce their survival fitness. There is a pressing need to establish sensitive and high throughput in vivo tools to systematically evaluate the immunosuppressive effects of contaminants in marine teleosts. This study reviewed a battery of in vivo immune function detection technologies established for different biological hierarchies at molecular (immune function pathways and genes by next generation sequencing (NGS)), cellular (leukocytes profiles by flow cytometry), tissues/organ system (whole adult histo-array), and organism (host resistance assays (HRAs)) levels, to assess the immune competence of marine medaka Oryzias melastigma. This approach enables a holistic assessment of fish immune competence under different chemical exposure or environmental scenarios. The data obtained will also be useful to unravel the underlying immunotoxic mechanisms. Intriguingly, NGS analysis of hepatic immune gene expression profiles (male > female) are in support of the bacterial HRA findings, in which infection-induced mortality was consistently higher in females than in males. As such, reproductive stages and gender-specific responses must be taken into consideration when assessing the risk of immunotoxicants in the aquatic environment. The distinct phenotypic sexual dimorphism and short generation time (3 months) of marine medaka offer additional advantages for sex-related immunotoxicological investigation.

Uno, Seiichi; Kokushi, Emiko; Kawano, Machi; McElroy, Anne; Koyama, Jiro

doi: 10.1007/s11356-016-7581-5pmid: 27623855

Toxic risks of sediments collected from seven sites in Tokyo Bay were evaluated using Japanese medaka embryos. Those sediments with slight pore water were placed in grass petri dishes without overlying water. The most remarkable effect in the field sediment was to cause hatching delay in embryos, and the longest time until hatching took was 12.5 ± 1.6 days post-fertilization (dpf), although that in control group was 10.1 ± 0.7 dpf. A significant delay in hatching was observed at four sites. Because total carbon concentrations were relatively high in sediments at three of these four sites, several chemicals were expected to be residues in these sites and could cause their delay. Although extreme mortality was not observed at all sites, sediments collected from the site close to Kawasaki city induced 10 % mortality. Polycyclic aromatic hydrocarbon (PAH) concentrations were remarkably high at this site compared with other sites, and thus PAH toxicities could be causing the mortality. Concentration of heavy metals such as cadmium, copper, lead, and zinc in sediments were also determined, but no clear relationship was found between toxicities to embryos and the distribution of their concentrations.

Maki, Benjamin; Hodges, Kathryn; Ford, Scott; Sofield, Ruth

doi: 10.1007/s11356-016-7852-1pmid: 27778268

Historic applications of lead arsenate pesticides and smelting activities have resulted in elevated concentrations of arsenic in Washington State soils. For example, old orchard topsoils in Washington have concentrations reaching upwards of 350 mg As/kg soil with an estimated 187,590 acres of arsenic contamination from pesticide application alone. Iron oxides have been indicated as a key factor in modulating the fate and transport of arsenic in the soil environment. We employed a factorial design to investigate the role of a specific iron oxide, hydrous ferric oxide (HFO), and terrestrial organisms on the mobility, bioavailability, and fate of arsenic and iron in locally collected soils. Earthworms in soils amended with both arsenic and HFO had 47.2 % lower arsenic tissue concentrations compared to those in soils only amended with arsenic. Similarly, arsenic leachate concentrations and plant tissue concentrations were lower when HFO was present, although this was with a reduced magnitude and was not consistently significant. A lack of significance of HFO in three of the linear models for leachate and plant bioavailability, however, indicates that the role of HFO in arsenic mobility, bioavailability, and fate is more complicated than can be explained by the simple addition or not of HFO. For example, our analyses showed that earthworms decreased pH and increased bioavailability for both arsenic and iron as demonstrated by increases in leachate and plant tissue concentrations. The mechanisms for this could include a biotransformation of earthworm-ingested arsenic combined with an earthworm-induced change in pH. We also found that arsenic amendments increased the mobility and bioavailability of iron, evidenced by increased iron concentrations in earthworms, plants, and leachate. A mechanistic explanation for this change in bioavailability is not readily apparent but does support a need for more work on bioavailability when mixtures are present. From these results, it is clear that a combination of biotic and abiotic factors influences metal/metalloid fate and transport in soils, with earthworms being one of the most important factors in our work. Study designs such as the factorial analysis can help to address the role each factor plays while efficiently generating new hypotheses and areas of inquiry; this approach can also bridge knowledge generated through reductionist and holistic approaches to complex environmental problems.