8

Traces of Trouble:

Hormones,Pharmaceuticals, and Toxic Chemicals

第八章

“痕量”的麻烦： 激素、药物和有毒化学品

In 1995, I was invited to give a talk at a scientific conference featuring the up-and-coming water pollution researchers. Of course I agreed to go. After all, I was flattered by the attention, and as a freshly minted assistant professor I knew that being identified as someone who stood out from his peers would be useful when it came time for tenure review. That the conference was to be held in Honolulu in mid-December had only a minor bearingon my decision to accept the invitation.

１９９５年我应邀在一个学术会议上做报告，这个会议是针对从事水污染研究的学生和即将毕业的年轻人。我理所当然地接受了邀请。毕竟，能收到这种邀请让我感到非常荣幸。而且，作为一名新的助理教授，我也知道能被同行认定为佼佼者，对我以后申请成为终身教授的审查过程会有益。会议定于１２月中旬在檀香山召开，这对我决定接受这一邀请的影响并不大。

Like most of the other speakers, I planned to slink off to the beach for a week of rejuvenation after giving my talk. To be polite, I had to attenda day of sessions with my colleagues, but that seemed like a small price topay. I wasn’t expecting to learn much, because I already knew most of the other presenters and had read their papers or seen them give talks at other conferences. I certainly didn’t anticipate that one of the talks would change the focus of my subsequent research and cause me to develop a deep skepticism about the ways in which cities obtain, treat, and dispose of water.

像大多数其他演讲者一样，我打算在做完报告后就开溜，去海边休假一星期。当然，为了礼貌，我必须跟我的同事们一起参加一天的会议，不过，这只是为了休假而付出的一个很小的代价。我并不期待能有很多收获，因为我认识大部分演讲者并阅读过他们的论文，或者在其他会议上聆听过他们的报告。我完全没有想到其中一个报告会让我改变后续的研究重点，并让我深深地质疑城市获取水、处理水和排放（污）水的方式。

The source of my trouble was a new graduate from Brunel University in England named Susan Jobling. I had never heard of any cutting edge research outthis tiny school just outside Landon and was surprised when she reported findings unlike anything I had ever read. Jobling talked about research she had recently completed as part of her Ph.D. under the supervision of John Sumpter, a biologist who had switched his research focus from the fundamentals of fish reproduction to water pollution upon learning of the alarmingly high prevalence in British rivers of male fish with eggs growing in their testes. Sumpter found out about this unusual phenomenon from British government researchers who had observed hermaphroditic fish in the River Lea, a tributary of the Thames River, starting in the early 1980s. Scientists working for the government-run utility, Thames Water, had quietly been trying to determine the extent of the phenomenon and its causes for several years when Sumpter and his students got involved. Bythe early 1990s, the combined team had documented the occurrence of male fishwith eggs growing inside their testes in urban rivers throughout Britain. They also had learned that sewage treatment plants were the source of the problem: when they placed male trout in cages immediately downstream of treatment plants, the fish started producing eggs after as little as two weeks of exposure. Something in sewage was turning male fish into hermaphrodites.¹

我对饮用水安全的关注，源自苏珊·乔布林，一名刚从英国布鲁内尔大学毕业的博士。我之前从来没有听说过来自于这所伦敦郊外的小学校的任何前沿性研究工作，但是听完她那与众不同的报告后，我大吃一惊。乔布林谈到她最近完成的研究结果，这是她的博士论文的一部分，是在她的导师———生物学家约翰·桑普特———指导下完成的。桑普特在得知英国河流中雄鱼睾丸内生长鱼卵的现象很普遍后，就将研究重心由鱼类生殖机理转向水体污染。２０世纪８０年代早期，英国政府研究人员就观察到泰晤士河的支流———利河———里有雌雄同体的鱼。当桑普特从那些政府研究人员那里得知这一不同寻常的现象后，他就和他的一些学生加入该研究。那时，为政府机构———泰晤士水务———服务的科学家们早已对这种现象的发生范围和原因在内部开展了数年的调查。到２０世纪９０年代初，这个联合研究团队记录下了全英国的城市河流里雄鱼睾丸内产生鱼卵的事件。他们也认识到污水处理厂是该问题的来源：当他们将装在网箱里的雄性鳟鱼放入污水处理厂的下游后，经过短短两个星期的环境暴露，雄性鳟鱼即开始产生鱼卵。这是因为污水里的不明物质使雄鱼雌性化了^［１］。

(Last two paragraphs of Chapter 8)

My encounter with Susan Jobling in 1995 led me to question the practice of using river as a dumping ground for sewage effluent. Initially, it was the presence of steroid hormones in effluent-dominated surface waters and their ability to feminize fish that drew my attention. After my colleagues and I learned that the problem could be solved by relatively simple measures, like improving the ability of the sewage treatment plant to remove organic matter or by adding a relatively inexpensive additional step, like chlorination, at the end of the treatment process, we turned our attention to the less potent manmade chemicals. We still do not know which, if any, of these chemicals might be causing subtle effects on the growth and reproduction of fish and other aquatic organisms that make their homes in effluent-dominated rivers, though it is clear that some of the compounds survive their trip to our drinking water treatment plants. In most cases, the concentrations of the difficult-to-remove compounds are so low that it is exceedingly unlikely that they will affect our health. But in a few cases, the manmade chemicals react with chemical disinfectants during drinking water treatment to produce potent mutagens or carcinogens. Initial evidence suggests that we might be able to eliminate some of these chemicals by upgrading our sewage and water treatment plants, but the total cost of such improvements is high.

我和乔布林在１９９５年的邂逅，让我开始质疑将污水排入河流这种做法的合理性。起初，是以污水为主导的地表水域存在类固醇激素及其能导致鱼类雌性化的问题引起了我的关注。我和我的同事们了解到，该问题可以采用相对简单的措施加以解决，如提高污水处理厂去除有机物的能力或添加一个相对廉价的额外步骤，如在处理的最后阶段采用氯气消毒。于是，我们将目光转向了低毒性的人造化合物。我们依旧不知道，这些人造化合物中的哪些，如果有的话，可以轻微地影响鱼类及其他栖息在污水主导的河流中的水生生物的生长发育和繁殖，尽管可以确定一些化合物在流向饮用水处理厂的途中没有被降解。大多数情况下，这些难以去除的化合物的浓度低至几乎不可能对人类的健康产生任何影响。但是在少数情况下，在饮用水处理阶段，人造化合物会与消毒剂反应，产生有效的诱变剂或致癌物。初步证据表明，我们或许可以通过升级现有的污水处理厂和饮用水处理厂来消除其中的一些化合物，但是这种升级的总耗费是巨大的。

In addition to activated carbon and ozone, there are numerousup-and-coming water treatment technologies that might be more effective than the retrofits that are currently being contemplated. Before we start investingin Water 3.1—an upgrade of our aging wastewater and drinking water systems to address the problems caused by trace amounts of chemicals in wastewater—we should consider approaches for breaking free of the nineteenth- and twentieth-century practice of using our rivers and drinking water supplies for waste disposal.

除了活性炭和臭氧，还有许多正在开发中的水处理技术也许会比当前使用的升级修复计划更有效。即将到来的水３．１，是为了升级我们陈旧的污水和饮用水处理厂，用以解决水中痕量化合物引起的问题。在为水３．１时代投资前，我们应当首先考虑从传统的生活方式中挣脱出来，不再沿用１９世纪和２０世纪的那套老办法，将河流和饮用水源用来处置废弃物。

ps. I typed up the English myself, so errors are possible.

水４．０：饮用水的过去、现在与未来

［美］戴维·塞德拉克　著

徐向荣　等译    虞左俊　校

上海科学技术出版社

出版时间：2015.08

ISBN：978-7-5478-2729-1

定价：38元

Water 4.0: The Past, Present, and Future of the World's Most Vital Resource

Paperback：March 31, 2015

by David Sedlak (Author)