tokens: Exposure to tobacco was characterized as low (< 5 cigarettes per day , n = 88 ears ), moderate ( 5 < or = cigarettes per day < 10 , n = 76 ) or high (> or = 10 cigarettes per day , n = 36 ). RESULTS : In exposed neonates , TEOAEs mean response ( across frequency ) and mean amplitude at 4000Hz was significantly lower than in non - exposed neonates .