The word cleansers is playable in Words With Friends™, no blanks required. Because it is longer than 7 letters, you would have to play off an existing word or do it in several moves.
Words With Friends™ Letter Score: 14
Highest Scoring Words With Friends™ Play In The Letters
Seven Letter Word Alert: (31 words)
ancress, careens, carless, censers, cereals, cleaner, cleanse, creases, earless, encases, enseals, ensears, lancers, leaners, leasers, recanes, reclass, reclean, relaces, resales, rescale, rescans, reseals, scalene, scalers, sclerae, scleras, screens, sealers, seances, secerns