過去幾十年間，

美國加州的海獅一直死於神秘癌症，直到近日，經過科學家們近20年研究，謎團終被揭開——海獅生存環境中存在過高含量的DDT，多氯聯苯等化學物質，正是其患癌的誘因。

美國加州大學聖地亞哥分校斯克裡普斯海洋研究所的科學家們透過一次科考，

發現

在距離南加州海岸僅35千米的聖卡塔利娜島和洛杉磯海岸之間，約145平方公里的海底有著至少27000個疑似裝有DDT農藥的桶狀物體。

Sea lions in California are facing a surge in cancer cases that are potentially linked to thousands of barrels of dichloro-diphenyl-trichloroethane （DDT）， a banned insecticide， that were dumped in the Pacific Ocean off the Southern California coast decades ago。

A research vessel from Scripps Institution of Oceanography at the University of California San Diego recently discovered and photographed over 27，000 barrels possibly containing the toxic substance DDT on the seafloor between Santa Catalina Island and the Los Angeles coast。

近期，加利福尼亞州索薩利托海洋哺乳動物中心的一項研究發現，大約五分之一的加利福尼亞成年海獅死於皰疹病毒引起的癌症。

該研究小組的另一項研究表明，多氯聯苯、人造工業化學品和DDT等汙染物在這種癌症的發展中起著重要的輔助作用。

A recent study conducted by the Marine Mammal Center in Sausalito， California， has found that approximately one in five California adult sea lions have died from cancer developed from a herpes virus in sea lions。

Another study led by the same team showed that pollutants such as Polychlorinated biphenyls （PCBs）， man-made industrial chemicals， and DDT play a significant role as co-factors in the development of this cancer。 This is particularly relevant to Southern California， where most of the sea lion population gathers each year to breed。

海洋哺乳動物像人類一樣哺育幼崽，壽命相對較長。毒素在它們的脂肪中不斷積累，並被影響人類的同種病毒感染。

Marine mammals nurse their young and live relatively long lives， like humans。 They accumulate toxins in their blubber and are sickened by the same kinds of viruses that affect humans。

“It is extraordinary， the level of pollutants in these animals in California。 It is a big factor in why we‘re seeing this level of cancer，” said Padraig Duignan， chief pathologist at the Marine Mammal Center and a co-author of the study。

“With all the dumping since the Second World War， right up to the 1970s， that’s a lot of stuff out there，” Duignan said。 “These legacy chemicals haven‘t broken down anything appreciable in intervening years， and nobody knows if they ever will。 This is something that they’re going to have to be exposed to for who knows how long。”

海洋哺乳動物中心是世界上最大的海洋哺乳動物醫院。自1979年首次發現海獅患癌症以來，研究人員發現中心醫院收治的18- 23%的成年海獅都死於這種致命的疾病。

The Marine Mammal Center is the world‘s largest marine mammal hospital。 Since cancer in sea lions was first discovered in 1979， researchers have found that between 18-23 percent of adult sea lions admitted to the Center’s hospital have died of the fatal disease。

TAG: CaliforniaDDTlionscancerSea