目前,对化学物质的慢性健康危害问题的探讨正处于发展政策和奠定法规基础的阶段。二十五年前,仅知道两种或三种化学物质对人致癌。现在,职业安全和卫生管理局(OSHA)已规定17种化学物质为致癌物,而美国职业安全和卫生研究所(NIOSH)则将2,415种列为可疑致癌物质。在谈及化学物质对健康的慢性危害时,作者指出: 第一,并非所有的化学物质都有益或都有害,都是人工合成的或都是天然的。自然界中的一切物质几乎都与化学物质有关。第二,化学致癌物和其他对键康有慢性危害的化学物质并非都是人工合成的。例如,能引起慢性病灶的石棉是一种化学物质,也是天然的致癌物;花生和粮食往往含有微量的黄曲霉毒素(一种强致癌物);木炭烤制的肉片中也含有致癌物苯并芘。第三,正常人所必需的多种微量化学物质,当摄入量过大时,对人体则有严重的急、慢性毒性。例如, At present, the discussion on the issue of chronic health hazards of chemical substances is at the stage of developing policies and laying the foundation of laws and regulations. Twenty-five years ago, only two or three chemicals were known to cause cancer in humans. Now OSHA has specified 17 chemicals as carcinogens, while the NIOSH lists 2,415 as suspected carcinogens. Speaking about the chronic health hazards of chemicals, the authors point out: First, not all chemicals are beneficial or harmful and are synthetic or natural. Almost everything in nature is related to chemicals. Second, chemical carcinogens and other chemicals that are chronic to Jiankang are not always synthetic. For example, asbestos, which causes chronic lesions, is a chemical as well as a natural carcinogen; peanuts and grains often contain trace amounts of aflatoxins (a strong carcinogen); carcinogenic benzols Pyrene. Third, many kinds of trace chemicals necessary for normal people, when the intake is too large, the human body has serious acute and chronic toxicity. E.g,