AN ANTI-pollution commercial last night won the J. Walter Thompson agency the award for best advertisement of the last decade. Chosen from among the Association of Accredited Advertising Agencies' Kam Fan winners between 1984 and 1993, the winning work shows a deaf girl using sign language to illustrate the problem of noise pollution. Another big winner at the association's Creative Awards Ceremony was Euro RSCG Ball, which, as it did last year, scooped the top three overall awards. The agency's advertisement for Toshiba air-conditioners won the best single television commercial; its Gallery Thirteen commercial won the best print ad category; and it also scooped this year's Kam Fan award. But out of a possible 60 gold awards, the judges only handed out 11. Expressing disappointment, Mr Jimmy Lam, co-chairman of the Creative Awards Committee, said: ''The last 12 months has not been a vintage year at all.''