抗焦慮藥物導致水質污染，影響鮭魚洄游（1/2）

 Recently Yahoo New on line picked up the following:

Salmon migration affected by drug pollution in water from antianxiety medication (1/2)

By Mindy Weisberger, CNN

Updated 12:08 PM EDT, Wed April 16, 2025

CNN

 —

Hatched in quiet streams and rivers, salmon undertake a perilous journey to reach the open ocean where they become mature adults. Over millions of years, generations of young salmon have migrated great distances, in some cases traveling hundreds of miles from freshwater systems to the sea. However, modern salmon face a hurdle that was unknown to their ancient ancestors: pharmaceutical pollution that changes their migration behavior.

Recently, researchers discovered that when a drug called clobazam accumulates in salmon’s brains, migrating fish reach the ocean sooner and navigate dam obstacles faster. On the surface, this change might seem helpful to salmon. However, any deviation from normal animal behavior through human activity — particularly when psychoactive substances are involved — is a red flag, and the full extent of how drug pollution may alter salmon health, behavior and reproduction is still unknown, scientists reported April 10 in the journal Science.

Clobazam, which is commonly found in wastewater, belongs to a group of medicines called benzodiazepines, which depress the central nervous system. The drug is used to prevent epileptic seizures, for short-term treatment of anxiety and to treat anxiety-related sleep disorders. But because neural wiring in fish resembles that of mammals, fish are highly susceptible to the effects of drugs that tweak human neurochemistry, said Dr. Christopher C. Caudill, a professor in the department of fish and wildlife sciences at the University of Idaho.

“Humans share a large amount of biological architecture with fishes — our physiology and anatomy are remarkably similar. Thus, it is intuitive that psychoactive drugs alter the behavior of both fishes and humans,” Caudill, who was not involved in the research, told CNN in an email.

Prior research showed that benzodiazepines could alter behavior in Atlantic salmon (Salmo salar), but they did so under conditions unlike those experienced by wild salmon, said study coauthor Dr. Marcus Michelangeli, a lecturer in the School of Environment and Science at Griffith University in Queensland, Australia.

“Those studies were largely conducted in laboratory settings, only tracked movement over short distances — less than 100 metres (328 feet) — or used drug concentrations much higher than what salmon would typically encounter in the wild,” Michelangeli said via email.

“Our study took a different approach. We followed the entire river-to-sea migration of juvenile salmon in a natural river system, using drug concentrations that match what fish are actually exposed to in the environment.”

The field investigation’s findings highlight the growing risks pharmaceutical pollutants pose to wildlife populations across the globe, according to Michelangeli.

(to be continued)

Translation

抗焦慮藥物導致水質污染，影響鮭魚洄游（1/2）

鮭魚在平靜的溪流和河流中孵化，經過危險的旅程才能到達廣闊的海洋並長大到成年。數百萬年來，一代又一代的幼鮭魚遷徙了很長的距離，有些甚至從淡水系統游到數百英里外的大海。然而，現代鮭魚面臨著其古代祖先所不知道的障礙：藥物污染改變了它們的遷徙行為。

最近，研究人員發現，當一種名為氯巴占(clobazam) 的藥物在鮭魚的大腦中積聚時，遷徙魚類可以更快到達海洋，並更快地避開水壩障礙物。從表面上看，這種變化似乎對鮭魚有益。然而，科學家在4月10日的《科學》雜誌上報告稱，任何因人類活動而導致的動物偏離正常行為 - 尤其是涉及能影響精神、情感或行為的任何物質時 - 都是一個危險信號，而藥物污染究竟會如何改變鮭魚的健康、行為和繁殖，目前仍不得而知。

氯巴占常見於廢水中，屬於苯二氮䓬 (benzodiazepines)類藥物，可抑制中樞神經。該藥物用於預防癲癇發作、短期治療焦慮症以及治療焦慮相關的睡眠障礙。但愛達荷大學魚類和野生動物科學系教授 Christopher C. Caudill 博士說，由於魚類的神經網絡與哺乳動物的相似，因此魚類很容易受到用於調整人類神經化學的藥物的影響。

未參與此研究的 Caudill 在一封電子郵件中告訴 CNN: 「人類與魚類擁有大量相同的生物結構 - 我們的生理和解剖學結構非常相似。因此顯而易見，能夠影響個體的心理狀態和行為的藥物都會改變魚類和人類的行為」。

該研究的共同作者、澳洲昆士蘭州 Griffith大學環境與科學學院講師 Marcus Michelangeli 博士說，先前的研究表明，苯二氮䓬類藥物可以改變大西洋鮭魚（Salmo salar）的行為，但它們改變行為的條件與野生鮭魚所經歷的條件不同。

Michelangeli 透過電子郵件表示： “這些先前研究主要在實驗室環境中進行，僅追蹤短距離 - 不到 100 公尺（328 英尺) - 的活動，或者使用的藥物濃度遠高於鮭魚在野外通常會遇到的濃度。”

“我們的研究採用了不同的方法。我們追蹤了自然河流系統中幼鮭魚從河流到海洋的整個洄游過程，使用的藥物濃度與魚類在環境中實際接觸到的濃度相匹配。”

Michelangeli表示，實地調查的結果凸顯了藥物污染物對全球野生動物族群造成的日益嚴重威脅。

（待續）