[' ', ' ', ' ', ' ', 'to', 'oS', 'vo', 'Itt.', 'Qk', 'dew', '5:', 'Test', 'for', 'Carcinogenicity', 'of', 'Food', 'Additives', 'and', 'Chemotherapeutic', 'Agents', 'by', 'the', 'Pulmonary', 'Tumor', 'Response', 'in', 'Strain', 'A', 'Mice!', '(CANCER', 'RESTARCH', '33,', '2069', '3085.', 'December', '1993)', 'Gary', 'D.', 'Stoner,', 'Michael', 'B.', 'Shimkin,', 'Atexis', 'J.', 'Kniazeff,', 'John', 'H.', 'Weisburger,', 'Elizabeth', 'K.', 'Weisburger,', 'and', 'Gio', 'B.', 'Gori', 'fA.', 'JK],', 'Shoot', 'of', 'Medicine,', 'University', 'of', 'California,', 'Sen', 'Diego,', 'Le', 'York', '10021', '[J', 'H.W],', 'and', 'Carcinogen', 'Metabolism', 'and', 'Toxicology', 'Branch', '{E', 'K', 'W.}', 'and', 'Division', 'of', 'Concer', 'Cause', 'and', 'Prevention', '1G', 'B', 'G},', 'National', 'Concer', 'Institute.', 'Bethesda,', 'Maryland', '20014', 'SUMMARY', 'Forty-one', 'food', 'additives', 'and', '20', 'chemotherapeutic', 'agents', 'were', 'examined', 'for', 'their', 'ability', 'to', 'induce', 'primary', 'lung', 'tumors', 'in', 'A', 'mice.', 'The', 'animals', 'received', 'ip.', 'injections', 'of', 'each', 'compound', 'for', '8', 'weeks', 'and', 'were', 'killed', 'at', '24', 'weeks', 'after', 'the', 'first', 'injection.', 'With', 'some', 'of', 'the', 'more', 'toxic', 'compounds,', 'fewer', 'injections', 'were', 'administered.', 'Two', 'or', 'three', 'dose', 'levels', 'were', 'used', 'for', 'each', 'chemical.', 'Cinnamy!', 'anthranilate', 'was', 'the', 'only', 'positive', 'of', 'the', '41', 'food', 'additives', 'tested.', 'Safrole', 'and', 'sodium', 'sacchann', 'were', 'negative', 'for', 'pulmonary', 'tumor', 'response', 'under', 'the', 'conditions', 'used.', 'Of', 'the', '20', 'chemotherapeutic', 'agents,', 'including', 'alkylating', 'chemicals,', '.2', 'were', 'found', 'to', 'be', 'positive', 'in', 'inducing', 'pulmonary', 'tumors.', 'U', 'acil', 'mustard', 'was', 'the', 'most', 'active', 'compound.', 'Myleran', 'was', 'inactive', 'at', 'the', 'dose', 'levels', 'used.', 'INTRODUCTION', 'The', 'testing', 'of', 'chemicals', 'in', 'the', 'human', 'environment', 'for', 'carcinogenic', 'activity', 'is', 'an', 'important', 'practical', 'aspect', 'of', 'studies', 'in', 'chemical', 'carcinogenesis.', 'With', 'the', 'steadily', 'increasing', 'chemical', 'burden', 'of', 'the', 'environment,', 'there', 'is', 'urgent', 'need', 'to', 'develup', 'bioassay', 'systems', 'that', 'are', 'more', 'rapid', 'and', 'reproducible', 'than', 'many', 'of', 'the', 'long-lerm', 'and', 'expensive', 'animal', 'test', 'systems', 'now', 'being', 'used.', 'Much', 'effort', 'is', 'being', 'expended', 'toward', 'the', 'development', 'of', 'suitable', 'im', 'vitro', 'bioassay', 'systems', 'but,', 'al', 'present,', 'there', 'is', 'no', 'in', 'vitro', 'system', 'adequate', 'to', 'assess', 'the', 'Carcinogenicity', 'of', 'a', 'broad', 'variety', 'of', 'environmental', 'chemicals.', 'Quantitative', 'estimation', 'of', 'carcinogenicity', 'still', 'depends', 'in', 'large', 'part', 'on', 'the', 'induction', 'of', 'some', 'reproducible', 'neoplastic', 'response', 'in', 'an', 'animal', 'test', 'system.', 'In', 'the', 'present', 'study,', 'the', 'A', 'mouse', 'pulmonary', 'tumor', 'system', 'developed', 'by', 'Andervont', 'and', 'Shimkin', '(2)', 'in', '1940', 'was', 'used', 'for', 'the', 'testing', 'of', 'a', 'series', 'of', 'food', 'additives', '(11)', 'and', 'chemothera-', 'peutic', 'agents', 'for', 'carcinogenic', 'activity', 'as', 'measured', 'by', 'an', 'increased', 'occurrence', 'of', 'pulmonary', 'tumors.', 'The', 'food', 'additives', 'were', 'selected', 'from', 'the', 'GRAS', '(generally', 'recognized', 'as', 'safe', 'for', 'human', 'consumption)', 'list', 'either', 'randomly', 'or', 'because', 'they', 'contained', 'double', 'bonds,', 'keto', 'groups,', 'several', 'methoxy', 'groups', 'on', 'a', 'benzene', 'ring,', 'or', 'other', 'structures', 'similar', 'to', 'those', 'of', ' ', '‘This', 'research', 'was', 'supported', 'by', 'Contract', '70-2206', 'from', 'the', 'National', 'Cancer', 'Institute.', 'Received', 'June', '1,', '1973;', 'accepted', 'August', '23,', '1973.', 'DECEMBER', '1973', 'known', 'carcinogens.', 'Among', 'the', 'drugs', 'are', 'several', 'that', 'have', 'been', 'used', 'for', 'the', 'treatment', 'of', 'leukemia,', 'lymphomas,', 'ot', 'other', 'neoplastic', 'diseases.', 'Three', 'of', 'these', 'compounds,', 'uracil', 'mustard,', 'Myleran,', 'and', 'thio-TEPA,’', 'were', 'tested', 'previously', 'in', 'this', 'system', '(15).', 'In', 'addition,', 'the', 'bioassay', 'has', 'been', 'applied', 'to', 'the', 'testing', 'of', 'polycyclic', 'hydrocarbons', '(2),', 'azo', 'dyes', '(2),', 'alkylating', 'agents', '(8,', '13,', '15),', 'carbamates', '(17),', 'and', 'aflatoxin', 'B,', '(21).', 'The', 'characteristic', 'features', 'of', 'the', 'system', 'have', 'already', 'been', 'discussed', 'extensively', 'by', 'Shimkin', 'et', 'af,', '(13-17).', 'MATERIALS', 'AND', 'METHODS', 'Animals.', 'Male', 'and', 'female', 'A/He', 'mice', 'were', 'purchased', 'from', 'the', 'Institute', 'for', 'Cancer', 'Research,', 'Philadelptua,', 'or', 'obtained', 'from', 'the', 'National', 'Cancer', 'Institute,', 'The', 'mice,', '6', 'to', '8', 'weeks', 'oid', 'and', 'weighing', 'an', 'average', 'of', '18', 'to', '20', 'g,', 'were', 'tanjomly', 'distributed', 'among', 'experimental', 'and', 'contrat', 'groups', 'The', 'animals', 'were', 'housed', 'in', 'groups', 'of', '5', 'in', 'plastic', 'boxes.', 'Commercial', 'grade', 'sawdust', 'chips', 'were', 'used', 'for', 'bedding.', 'Purina', 'laboratory', 'chow', 'and', 'water', 'were', 'available', 'ad', 'fibirum', 'Hygienic', 'conditions', 'were', 'maintained', 'by', 'twice', 'weekly', 'changes', 'of', 'the', 'animal', 'cages', 'and', 'water', 'bottles', 'and', 'weekly', 'disinfection', 'of', 'the', 'animal', 'quarters.', 'The', 'water', 'bottles', 'were', 'routinely', 'stenhizea', 'All', 'chenucals', 'tested', 'were', 'stored', 'and', 'prepared', 'for', 'injection', 'in', 'S¢parate', 'rooms', 'al', 'a', 'distance', 'from', 'the', 'animals', 'Chemicals.', 'The', 'compounds,', 'their', 'structural', 'formulas,', 'molecular', 'weights,', 'source,', 'and', 'lol', 'or', 'code', 'numbers', 'are', 'listed', 'in', 'Table', '1.', 'As', 'indicated,', 'the', 'food', 'additives', 'were', 'obtained', 'by', 'purchase', 'from', 'various', 'chemical', 'supply', 'houses', 'They', 'ranged', 'in', 'purity', 'from', '85', 'to', '99%,', 'with', 'the', 'majonty', 'at', '95', 'to', '99%', 'Seventeen', 'of', 'the', '20', 'clinical', 'drugs', 'were', 'made', 'avauable', 'by', 'Dr.', 'Harry', 'B.', 'Wood,', 'Jr,', 'of', 'the', 'Cancer', 'Chemotherapy', 'National', 'Service', 'Center,', 'Bethesda,', 'Md.', 'Didenzyline,', 'phenazopyridine,', 'and', 'tolbutamide', 'were', 'obtained', 'from', 'the', 'manufacturers', 'indicated', 'in', 'the', 'table.', 'Urethan', '{m.p.,', '50°)', 'was', 'obtained', 'from', 'Matheson,', 'Coleman', 'and', 'Bell,', 'Los', 'Angeles,', 'Calif.', 'The', 'food', 'additives', 'were', 'routinely', 'stored', 'at', '4°.', 'Solutions', 'of', 'these', 'compuunds', 'were', 'prepared', 'fresh', 'weekly', 'for', 'injection', 'The', 'more', 'reactive', 'chemotherapeutic', 'compounds', 'were', 'stored', 'at', '~20°,', 'and', 'solutions', 'were', 'freshly', 'prepared', 'immediately', 'befor:', 'injection.', 'All', 'chemicals', 'were', 'stored', 'in', 'the', 'dark,', 'and', '‘The', 'abbreviations', 'used', 'ase:', 'thio-TEPA,', 'N,N‘', 'WN"', '-triethylenethio-', 'Phosphoramide,', 'SSV,', 'steroid', 'suspending', 'vehicle,', 'MTD.', 'maximally', 'tolerated', 'single', 'dose.', '3069', '238', 'L6PT', '900TS']