际关系造成的影响。

The impacts of energy technologies on public health and safety are difficult to pin down with much confidence. In the case of air pollution from fossil fuels, in which the dominant threat to public health is thought to be particulates formed from sulfur dioxide emissions, a consensus on the number of deaths caused by exposure has proved impossible. Widely differing estimates result from different assumptions about fuel compositions, air pollution control technology, power-plant sitting in relation to population distribution, meteorological conditions affecting sulfate formation, and, above all, the relation between sulfate concentrations and disease.

能源技术对于大众健康和安全所造成的影响难以确定。以矿物燃料造成的空气污染为例，一般认为其对大众健康的主要危害是由排放的二氧化硫形成的微粒，但接触这种污染空气究竟会导致多少人死亡，却无法取得一致意见。各种估算数据千差万别，原因在于对以下各种因素的分析各不相同，比如燃料构成、空气污染防治技术、发电厂选址同人口分布之间的关系、气象条件对硫化物形成的影响，最重要的是硫化物浓度与疾病之间的关系。

Large uncertainties also apply to the health and safety impacts of nuclear fission. In this case, differing estimates result in part from differences among sites and reactor types, in part from uncertainties about emissions from fuel-cycle steps that are not yet fully operational (especially fuel reprocessing and management of uranium-mill tailings) and in part from different assumptions about the effects of exposure to low-dose radiation. The biggest uncertainties, however, relate to the probabilities and consequences of large accidents at reactors, at reprocessing plants and in the transport of wastes.

同样，核反应堆对于大众健康和安全的影响亦无法确定。对此种影响的各种估测，既有来自关于反应堆选址和类型的不同观点，又有因为核燃料反应过程(尤其是核燃料回收以及铀选矿尾矿管理)还不完备，这些环节所产生的废弃物究竟会产生何种影响尚无法确定；同时还有因为对于人类接触少量核辐射所造成的后果各执己见。然而，最大的不确定性来自核反应堆、重新加工工厂以及核废料运输过程中可能发生重大事故的概率及所造成的后果。

Altogether, the ranges of estimated hazards to public health from both coal-fired and nuclear-power plants are so wide as to extend from negligible to substantial in comparison with other risks to the population. There is little basis, in these ranges, for preferring one of these energy sources over the other. For both, the very size of the uncertainty is itself a significant liability.

同人类面临的其他威胁相比，火电厂和核电厂危害大众健康的程度究竟有多大，众说纷纭，莫衷一是。有的人认为这种影响微不足道，可以忽略不计；也有人认为这种影响程度严重、危害巨大。无论影响大小，都没有理由对种种能源亲此疏彼。无论是核电还是火电，其对人类的危害都无法确定，这本身就是一大憾事。

Often neglected, but no less important, is the public health menace from traditional fuels widely used for cooking and water heating in the developing world. Perhaps 80 percent of global exposure to particulate air pollution occurs indoors in developing countries, where the smoke from primitive stoves is heavily laden with dangerous hydrocarbons. A disproportionate share of this burden is borne, moreover, by women (who do the cooking) and small children (who indoors with their mothers).

发展中国家普遍用于做饭烧水的传统燃料对大众健康造成的危害常常不为人们所关注，但同样十分严重。全球大约80%的颗粒空气污染来自发展中国家的室内烧煮，原始炉灶排出的烟气中含有大量有害的烃（或碳氢化合物），而且这种有害物质的受害者往往是妇女（室内烧煮的主要承担者）和儿童（长时间同母亲一起呆在室内）。

The ecological threats posed by energy supply are even harder to quantify than the threats to human health

and safety from effluents and accidents. Nevertheless, enough is known to suggest they portend even larger damage to human well-being. This damage potential arises from the combination of two circumstances. 同排放的废弃物和能源设施事故对大众健康造成的危害相比，能源利用对生态系统的威胁更难以量化。然而，根据已有认识足以判断这种威胁对人类健康造成的损失将会更大。这种潜在的损失是由两种情形同时存在导致的。

First, civilization depends heavily on services provided by ecological and geophysical processes such as building and fertilizing soil, regulating water supply, controlling pests and pathogens, and maintaining a tolerable climate; yet it lacks the knowledge and the resources to replace nature’s services with technology. Second, human activities are now clearly capable of disrupting globally the processes that provide these services. Energy supply, both industrial and traditional, is responsible for a striking share of the environmental impacts of human activity. The environmental transition of the past 100 years － driven above all by a 20-fold increase in fossil-fuel use and augmented by a tripling in the use of traditional energy forms － has amounted to no less than the emergence of civilization as a global ecological and geochemical force.

首先，人类文明严重依赖于各种生态和地球物理过程所提供的各种服务，诸如造土培肥（或土壤的形成与增肥）、水源调节、病虫害控制、适宜气候的维持等等。但是，人类缺乏知识和资源来利用技术代替自然界所提供的各种服务。其次，人类活动显然能够在全球范围破坏提供这些服务的进程。无论是工业能源还是传统能源使用，在人类活动引起的环境问题中均占有很大比重。过去100年以来的环境巨变（首要驱动因素是化石燃料的使用增长了20倍，同时传统能源的使用增长了3倍），可以说无异于人类文明作为一支全球范围内的生态和地球化学力量的崛起过程。

Of all environmental problems, the most threatening, and in many respects the most intractable, is global climate change. And the greenhouse gases most responsible for the danger of rapid climate change come largely from human endeavors too massive, widespread and central to the functioning of our societies to be easily altered: carbon dioxide (CO2) from deforestation and the combustion of fossil fuels; methane from rice paddies, cattle gusts and the exploitation of oil and natural gas; and nitrous oxides from fuel combustions and fertilizer use.

在诸多环境问题中，对人类威胁最大、在许多情况下却又最让人类无计可施的是全球气候变化。而对气候剧变最起作用的温室气体主要来自人类活动，这些活动规模之大、范围之广、对人类社会运转作用之大，都无法轻易改变。这些气体包括：由于毁林和燃烧矿物燃料所造成的二氧化碳，由秸秆、牲畜粪便和使用石油天然气所排放的甲烷，以及由于燃料燃烧和施肥所排放的一氧化二氮。

The only other external cost that might match the devastating impact of global climate change is the risk of causing or aggravating large-scale military conflict. One such threat is the potential for conflict over access to petroleum resources. Another threat is the link between nuclear energy and the spread of nuclear weapons. The issue is hardly less complex and controversial than the link between CO2 and climate; many analysts, including me, think it is threatening indeed.

其他唯一能同全球气候变化所造成的灾难性影响相提并论的外化成本是发生或恶化大规模军事冲突的可能。其中潜在的威胁是为争夺石油资源而引起的冲突。另一个威胁则来自核能和核武器扩散之间的联系，这种联系的复杂性几乎不亚于二氧化碳和气候之间的关系。许多分析家（包括本人）均认为这种关系十分危险。