The purpose of this project is to analyze and study the absorption of the substances ivermectin, spinosad and barettin to hydrophobic and hydrophilic surfaces, and to analyze and study if the barnacle larva are effected when they try to settle on the treated surface. Incubation tests with barnacle larva in Petri dishes were performed as well as absorption tests on hydrophobic and hydrophilic surfaces which were tested with ellipsometry. To determine the surface thickness. The barnacles were placed in hydrophobic as well as hydrophilic Petri dishes that had been incubated with ivermectin, spinosad or barettin. After four to six days the larva was counted to analyze the settling. From the results conclusions could be drawn about the adsorption abilities of the substances to the different surfaces. The barnacles were placed in hydrophobic as well as hydrophilic Petri dishes that had been incubated with ivermectin, spinosad or barettin. After four to six days the larva was counted to analyze the settling. From the results conclusions could be drawn about the adsorption abilities of the substances to the different surfaces. To analyze the adsorption abilities, pieces of silicon oxide were prepared with hydrophobic and hydrophilic poly dimethyl siloxan groups, and albumine. The pieces were then analyzed with ellipsometry. The larva's mortality was very high in the first tests. It can be explained with them being stored too cold the first days, which might have caused their death. It might also be because of contamination from the net used to move the larva, since it was in contact with all the substances concentrations. The standard deviations from the ellipsometry tests are very high, most likely due to uneven adsorption of the substances to the surface. With more tests and measurements, more accurate results could have been sustained The purpose of this project is to analyze and study the absorption of the substances ivermectin, spinosad and barettin to hydrophobic and hydrophilic surfaces, and to analyze and study if the barnacle larva are effected when they try to settle on the treated surface. Incubation tests with barnacle larva in Petri dishes were performed as well as absorption tests on hydrophobic and hydrophilic surfaces which were tested with ellipsometry. To determine the surface thickness. The barnacles were placed in hydrophobic as well as hydrophilic Petri dishes that had been incubated with ivermectin, spinosad or barettin. After four to six days the larva was counted to analyze the settling. From the results conclusions could be drawn about the adsorption abilities of the substances to the different surfaces. The barnacles were placed in hydrophobic as well as hydrophilic Petri dishes that had been incubated with ivermectin, spinosad or barettin. After four to six days the larva was counted to analyze the settling. From the results conclusions could be drawn about the adsorption abilities of the substances to the different surfaces. To analyze the adsorption abilities, pieces of silicon oxide were prepared with hydrophobic and hydrophilic poly dimethyl siloxan groups, and albumine. The pieces were then analyzed with ellipsometry. The larva's mortality was very high in the first tests. It can be explained with them being stored too cold the first days, which might have caused their death. It might also be because of contamination from the net used to move the larva, since it was in contact with all the substances concentrations. The standard deviations from the ellipsometry tests are very high, most likely due to uneven adsorption of the substances to the surface. With more tests and measurements, more accurate results could have been sustained