Coal ash is known to contain dangerous elements including arsenic, lead, and selenium, yet the TVA refused at first to issue any health warnings about contamination from the spill.

煤灰渣含有多种危险物质，包括砷、铅、硒等，然而田纳西流域管理局起先矢口否认煤灰渣中含有对健康有害的物质。

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Selenium is one of the trace elements closely related to human health.

硒是与人体健康密切相关的必需微量元素之一。

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Water contains strontium, lithium, zinc, selenium and other seventeen kinds of trace elements beneficial to human body, the treatment of a variety of diseases have marked effect.

水中含有锶、锂、锌、硒等十七种对人体有益的微量元素，对治疗多种疾病有显效。

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Among the technologies are new ways of making already-commercialized formulations, like amorphous silicon and cadmium telluride, and newer formulations like CIGS, named for the elements it is made out of, copper, indium, gallium and selenium, and CIS, which leaves out the gallium.

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