| 1. | Incomplete combustion is the principal source of man-made carcinogens .
不完全燃烧是人为致癌物的主要来源。 |
| 2. | Some industrial chemicals and food additives are known to be cancer-producing .
已知有些工业上的化学物质和食物附加物是致癌的。 |
| 3. | The airborne carcinogens are in the atmosphere as absorbed matter on soot particles .
空气传播的致癌物在大气中是烟炱粒子上吸附的物质。 |
| 4. | For example, fragments resembling dna from cancer-causing viruses might be removed and destroyed .
例如，可能除掉或破坏类似来源于致癌病毒的DNA片段。 |
| 5. | Other examples are cell damage caused by silica, asbestos and possibly some carcinogens .
另外的例子是二氧化硅、石棉和可能的某些致癌物质所引起的细胞损害。 |
| 6. | Chemical carcinogens generally require metabolic conversion to some form of "ultimate" carcinogen .
化学致癌物一般需要通过代谢来转换成某种形式的“最终”致癌物。 |
| 7. | Chemical carcinogenesis in culture has proved to be a much more difficult field of investigation than viral carcinogenesis .
在培养内化学致癌已证明是一个比致癌困难得多的研究领域。 |
| 8. | Several compounds that are carcinogenic to animals have been identified in urban air in all large cities in which surveys have been conducted .
在考察过的所有大城市的空气中，已鉴定出几种化合物对动物是致癌的。 |
| 9. | Bioassays on the skin, subcutaneous tissue, cervix, and trachea of experimental animals have shown that particulate matter of urban air can be carcinogenic in the intact animal .
对实验动物的皮肤、皮下组织、颈和气管的生物鉴定表明，城市空气中的颗粒物质对健康动物可能是致癌的。 |
| 10. | The issue of airborn carcinogens in the non-occupational environment was thoroughly reviewed by the committee on biologic effects of atmospheric pollutions of the national academy of sciences .
关于非职业环境大气中的致癌物问题，美国国家科学院大气污染生物效应委员会已作了详尽的论述。 |
