minimal degree resurface, and they will be a source of oil com pounds for marine organisms through leakage and dis solution, as the chemical equilibrium for oil compounds between the water phase and the oil droplets continu ously will vary. Use of dispersants Bioactive compound after an acute oil spill, as demonstrated by the extensive use of the dispersant Corexit 9500 during the Deepwater Horizon accident in the Gulf of Mexico in 2010, will increase the amounts of oil droplets in the seawater column. The main purpose of using dispersant is to move the oil into the water column as oil dispersions which will dilute and biodegrade the oil more rapidly than if the oil was left on the surface. More knowledge is needed on the fate and effects of oil droplets in the water column in terms of lifetime, adhesion to particles, dissolution rates and not at least their toxicity to sensitive marine organisms.

Fish embryo and larvae are generally Inhibitors,Modulators,Libraries regarded to be par ticularly vulnerable to the toxic compounds in crude oil. Exposure studies carried out with pink salmon and pacific herring embryos Inhibitors,Modulators,Libraries after the Exxon Valdez accident showed that dissolved PAHs alone are sufficient for toxic impacts. Studying zebrafish, Carls et al. exposed fish embryos in a physical barrier separating dissolved PAH from oil dro plets, and showed comparable biological responses to water containing either dissolved PAH alone, or dissolved PAH plus droplets. We recently evaluated the potential contribution of oil droplets to the toxicity of dispersed oil to first feeding Atlantic cod larvae, and observed that it was mainly the water soluble fraction of oil and not the oil droplets themselves that induced altered gene transcription of detoxifying enzymes in the fish larvae.

From these studies it appears that oil droplets characteristics do not attribute to the toxic effects of PAH and other components in crude oil to fish embryo and lar vae, however, very little is known about whether or not chemically dispersed Inhibitors,Modulators,Libraries oil droplets have the same toxic effects as mechanistically Inhibitors,Modulators,Libraries dispersed oil droplets on fish lar vae. Most literature studies have compared the toxic effects of chemically and mechanically dispersed oil by comparing the toxicity of low energy water accommodated fractions or high energy water accommodated fractions, with chemically enhanced water accommo dated fractions.

Such comparisons may be use ful Drug_discovery in terms of comparatively testing the impact of the dispersant application, however, in terms of oil exposure, the two approaches differ significantly. things Generation of CE WAF will increase the oil concentration in the water phase and cause formation of very small oil droplets which will persist for a longer period of time in the water phase com pared to WSFs generated using the LE WAF or HE WAF approach. Often there is no information given on the oil droplet characteristics. In other words, dispersions generated with equal energy in put with and without dispersant therefore creates disper sions differing