| 1. |
|
|
| 2. |
- Blanck, Hans, 1950, et al.
(författare)
-
New strategy for design of optimised combinations of antifoulants: mixture efficacy predictions, risk weighting and microcapsule technology
- 2008
-
Ingår i: 14th International Congress on Marine Corrosion and Fouling, July 2008, Kobe Japan.
-
Konferensbidrag (refereegranskat)abstract
- Organisms differ in their sensitivity to toxicants, and each biocide will have its own efficacy profile. Whenever an antifoulant is used to affect organisms beyond its high-efficacy profile, an excess of biocides will be emitted to the environment. We propose an unprejudiced and rational design of efficacy-optimised combinations with minimum environmental risk. To control release of several antifoulants independently we use microcapsules bound to a polymer coating. The approach is based on three initial steps: Mixture toxicity concepts are used to predict efficacy of >100 000 combinations of 2-8 antifoulants. Predictions are based on full concentration-efficacy relationships with regard to prevention of settling of fouling model organisms (e.g. periphyton, sea lettuce, barnacles, sea squirt, blue mussel). Based on the predictions we will identify a set of > 100 000 combinations that are efficacious to all model organisms, and define their mixture concentrations and mixture ratios. Risk ratios (e.g. PEC/ PNEC) for the individual antifoulants are then used as weighing factors to rank the combinations according to their estimated relative risk to the environment. This results in a set of promising antifoulant combinations defined by their constituents, mixture ratios and total concentrations in water. The release rate from each of the individual mixture components will be regulated by microcapsule numbers, chemical and physical properties, to deliver the expected combination at the surface of the ship hull. The flexibility of the paint formulation ・with one antifoulant only in each capsule ・suggests that the coating can easily be reformulated to adjust to more demanding conditions. This study is a part of the Marine Paint Research Programme funded by MISTRA, the Foundation for Strategic Environmental Research, Sweden.
|
|
| 3. |
|
|
| 4. |
|
|
| 5. |
- Eriksson, Martin, 1970, et al.
(författare)
-
Long-term effects of lowered pH on marine periphyton communities
- 2011
-
Ingår i: SETAC (Society of environmental Toxicology and Chemistry) Europe, 21st Annual Meeting.
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The phenomenon of Ocean Acidification has been identified as a potential threat to several marine organisms and might lead to adverse disturbances of marine ecosystems. Although the knowledge about effects of rising acidity in the oceans is increasing for some species, the knowledge of these effects on the community level of biological complexity is very scarce. Still, community-level effect indicators are needed in order to predict direct and indirect effects of Ocean Acidification on marine ecosystems. In a community the organisms live in their realized niche with important ecological interactions (e.g. competition, grazing and predation) present. This gives community approaches in ecotoxicological tests high ecological relevance. Since lowered pH might eliminate species or strains that are sensitive to such stress, and select for the ones that are more competitive under this condition, a community approach have the potential to detect any pH-induced change in community structure or function. We have used marine periphyton communities in a long-term study of effects of increased partial pressure of CO2 in the water and the accompanied lowering of pH. Periphyton was allowed to colonize and grow on glass substrata for 3.5 weeks in flow-through microcosms. The pH in the microcosms was either that of the incoming natural surface water or was manipulated by bubbling of CO2 down to approximately 7.7. We used Pulse Amplitude Modulation (PAM) to detect effects on photosynthetic electron transport and estimate induced community tolerance to low pH. In addition, we used confocal microscopy to trace effects on biofilm architecture and biofilm thickness. We have also estimated microbial diversity and composition of trace elements in periphyton using PCR-TGGE and X-ray fluorescence respectively. First results indicate that long-term effects of lowered pH change the capacity of communities to tolerate further changes in pH, making them more sensitive to pH-stress. However, no long-term effects on photosynthetic electron transport or trace element composition was detected.
|
|
| 6. |
|
|
| 7. |
|
|
| 8. |
|
|
| 9. |
|
|
| 10. |
|
|
