['Walker,', 'Nelson,', 'Cain,', 'Utell,', 'Joyce,', 'Morgan,', 'Steichen,', 'Pritchard', 'and', 'Stancill', 'Table', '3', 'Changes', 'in', 'each', 'sensory', '/symptom', 'attribute', 'from', 'the', 'pre-smoking', 'baseline', 'to', 'the', 'smoke', 'plateau', '(minutes', '21-70).', 'The', 'mean', 'values', 'underlined', 'are', 'significantly', 'different', 'from', 'the', 'values', 'obtained', 'in', 'the', 'no-smoking', 'CONTROL', 'condition,', 'Except', 'for', 'Overall', 'acceptance,', 'for', 'which', 'the', 'maximum', 'possible', 'effect', 'of', 'ETS', 'exposure', 'would', 'correspond', 'to', 'a', 'value', 'of', '—1.0,', 'a', 'maximum', 'value', 'of', '60', 'was', 'possible', 'for', 'these', 'attributes', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', 'Sensory', '/symptom', '1', '2', '3', '4', '5', '6', 'attribute', 'Controt', 'Odor', 'strength', '0.78', '5.64', '5.87', '5.76', '7.12', '11.35', 'Nasal', 'irritation', '1.16', '3.29', '3.99', '4.23', '5.56', '8.09', 'Eye', 'irritation', '0.35', '3.83', '4,15', '4.06', '6.00', '10.43', 'Annoyance', '1.03', '3.96', '4.23', '454', '5.50', '10.86', 'Overall', 'acceptance', '-0.01', '0,24', '-0.20', '-0.27', '~0,29', '—0.47', 'Difficulty', 'breathing', '0.39', '171', '1.96', '1.61', '2.87', '3.82', 'Throat', 'dryness', '1.39', '3.10', '4.06', '3.35', '4.66', '6.57', 'Eye', 'dryness', 'or', 'LIL', '4.38', '4.49', '5.06', '6.16', '9.40', 'Throat', 'irritation', '1.15', '2.28', '3,23', '2.90', '3,82', '6.56', 'Chest', 'tightness', '0.59', '1.46', '1,90', '1.32', '2.09', '2.98', 'Headache', '0.43', '2.01', '1.96', '241', '2.06', '3.68', 'Tiredness', 'or', 'fatigue', '3.60', '3.87', '4.33', '3.57', '3.86', '3.71', 'Haze', '0.68', '243', '249', '2.25', '2.87', '455', ' ', 'ceptable', 'during', 'the', 'smoke', 'plateau', 'period', 'than', 'in', 'the', 'pre-smoking', 'baseline.', 'The', 'magnitudes', 'of', 'the', 'ratings', 'were', 'monotonically', 'related', 'to', 'ETS', 'intensity,', 'although', 'participants', 'experienced', 'some', 'difficulty', 'in', 'discrimi-', 'nating', 'among', 'the', 'three', 'lowest', 'ETS', 'levels.', 'Perhaps', 'the', 'clearest', 'example', 'is', 'Overall', 'Acceptance.', 'Declines', 'in', 'the', 'proportion', 'of', 'participants', 'rating', 'the', 'air', 'unacceptable', 'were', 'progressively', 'smaller', 'as', 'ETS-RSP', 'level', 'was', 'de-', 'creased', 'from', '765', 'to', '113', 'pg/m*,', 'but', 'the', 'results', 'with', 'the', 'lowest', 'level', 'deviated', 'from', 'this', 'trend.', 'We', 'hypothesize', 'that', 'this', 'was', 'due', 'primarily', 'to', 'factors,', 'such', 'as', 'draft', 'and', 'noise,', 'associated', 'with', 'the', 'high', 'ventilation', 'rate', '(see', 'Table', '1)', 'used', 'to', 'achieve', 'this', '58', 'pg/m?', 'ETS-RSP', 'level.', 'Respiratory', 'Responses', ';', 'Data', 'for', 'each', 'of', 'the', 'eight', '10-minute', 'time', 'blocks', 'after', 'smoking', 'began', 'were', 'expressed', 'as', 'percentage', 'changes', 'from', 'the', '10-minute', 'pre-smoking', 'baseline', '(Fig.', '8).', 'ETS', 'levels', 'significantly', 'different', 'from', 'the', 'CONTROL', 'con-', 'dition', 'are', 'denoted', 'by', 'filled', 'symbols.', 'The', 'general', 'pat-', 'tern', 'is', 'consistent', 'with', 'recent', 'findings', 'from', 'this', 'labora-', 'tory', '(Walker', 'et', 'al.,', '1993)', 'in', 'that', 'reduced', 'breathing', 'fre-', 'quency,', 'but', 'no', 'change', 'in', 'minute', 'ventilation,', 'occurred', 'during', 'ETS', 'exposure.', 'Comparison', 'of', 'the', 'second', 'and', 'third', 'panels', 'of', 'Figure', '8', 'demonstrates', 'that', 'this', 'was', 'ac-', 'complished', 'primarily', 'by', 'increases', 'in', 'expiratory', 'time,', 'which', 'showed', 'the', 'greatest', 'percentage', 'change.', 'Al-', 'though', 'the', 'increase', 'in', 'tidal', 'volume', 'was', 'statistically', 'significant', 'for', 'only', 'a', 'few', 'level-by-time', 'period', 'combi-', 'nations,', 'these', 'increases', 'were', 'of', 'sufficient', 'magnitude', 'that', 'minute', 'ventilation', 'was', 'preserved', 'as', 'breathing', 'fre-', 'quency', 'declined.', 'Whereas', 'progressively', 'greater', 'sensory/symptom', 'changes', 'were', 'observed', 'with', 'increasing', 'ETS', 'levels,', 'this', 'was', 'not', 'seen', 'with', 'the', 'respiratory', 'results.', 'For', 'the', 'range', 'of', 'ETS', 'intensities', 'employed,', 'the', 'respiratory', 'responses', '182', ' ', 'manifested', 'an', '“all', 'or', 'none”', 'nature', 'in', 'that', 'the', 'magni-', 'tude', 'of', 'an', 'ETS', 'effect', 'of', 'these', 'respiratory', 'parameters', 'was', 'equivalent', 'for', 'the', 'five', 'ETS', 'intensities.', 'As', 'dis-', 'cussed', 'below,', 'this', 'and', 'other', 'features', 'of', 'the', 'breathing', 'Breaths/Min', 'Inspir.', 'Time', '—', 'Expir.', 'Time', 'Tidal', 'Vol.', ' ', '2', '8', '4', '0', '6', '4', '2', '0', '2', '8', '4', '0', '4', '8', '4', '0', 'Al', 'Bt', 'Minute', 'Ventil.', 'I', '0', '10', '20', '30', '40', '50', '60', '70', '80', '90', 'Minutes', 'Fig.', '8', 'Average', 'percentage', 'changes', 'in', 'breathing', 'frequency,', 'expira-', 'tory', 'time,', 'inspiratory', 'time,', 'tidal', 'volume', 'and', 'minute', 'ventilation', 'for', 'each', 'of', 'the', 'eight', '10-minute', 'time', 'blocks', 'after', 'smokers', 'began', 'to', 'puff', 'on', 'unlit', '(for', '1,', 'the', 'CONTROL', 'condition)', 'or', 'lit', 'cigarettes.', 'As', 'with', 'the', 'sensory', '/symptom', 'ratings,', 'values', 'significantly', 'differ-', 'ent', 'from', 'the', 'CONTROL', 'condition', 'are', 'denoted', 'with', 'filled', 'sym-', 'bols.', ' ', ',', '68e6', '9SvcS']