It is interesting to note, that the application rate of copolymer paint 

 applied in fresh water has been estimated to be about 1%. For antifouling 

 paints with copper as the active ingredient, has been estimated to be 

 about 2.7% (Lucas and Williams, 1987). 



3.5.5 Paint Choice by Type of Vessel 



The largest number of vessels coated with tributyltin are recreational 

 vessels. Ninety two and a half percent of all the vessels surveyed by 

 Lucas and Williams (1987) were recreational vessels and 60 percent of 

 those vessels were painted with tributyltin antifouling paints. However, 

 there are no good means to estimate the amount of painted surface area 

 which is represented by this large recreational fleet, but the numbers of 

 boats involved indicate that the recreational fleet is a significant 

 source of TBT to coastal waters. This is true for several reasons. One, 

 the large numbers of boats involved spread the sources of paint contact 

 over a major portion of coastal water. There is hardly a creek or harbor 

 near any metropolitan area which does not have several recreational boats 

 berthed there. The second aspect of exposure of TBT by recreational boats 

 is the infrequency of their use and lack of movement from the place where 

 they are kept. The third significant factor involving recreational craft 

 is their principal use to date of cheaper, high leach-rate, 

 free-association commercial TBT paints. 



One of the surprises of the Lucas and Williams (1987) survey is the 

 relatively low percentages of cargo vessels which reported being painted 

 with TBT copolymer/self polishing paint considering the publicized 

 advantages of this paint type for reducing fuel costs and improving 

 speed. Only 13% of the cargo vessels were reported being painted with 

 self polishing copolymer paints as compared with 18% of the recreational 

 boats, and free association was used on only 36% of the cargo vessels and 

 43% of the recreational boats surveyed. This data may have a unique bias 

 because not many new commercial ships are being built in the U.S. at this 

 time, and the omission of such would significantly lower the volume to 

 organotin antifoulant paints used in the cargo vessel category surveyed. 



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