In a study published in the journal Ambio, scientists found that lead levels in soil in the North-eastern United States had decreased markedly since the introduction of unleaded gasoline.

在《人类环境杂志》上发表的一项研究称，科学家们发现，自引进无铅汽油以来，美国东北部土壤中的铅含量已经显著下降。

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Her blood has lead levels of 261 — more than double the standards for safety.

她的血铅值在261，比安全标准值的两倍还多。

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Health risks in children at various blood lead levels, in micrograms per liter.

不同的血铅水准对儿童健康的风险有别，以下数值单位为微克每升。

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The male brains, especially nerve cell rich parts of the brain associated with thinking and remembering, seemed to have sustained more long term damage from high lead levels than the brains of the young women.

VOA: standard.2009.12.19

Eating a high fat diet but one that's low in cholesterol can still potentially lead to high cholesterol levels.

食用高脂但低胆固醇的食物,仍可导致胆固醇含量偏高

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

All these components ultimately lead to higher levels of success.

所有这些因素最终导致更高层次的成功。

哈佛公开课 - 幸福课课程节选

It is a particular risk for young children, who suffer significant developmental problems if exposed to elevated lead levels.

BBC: US rice imports 'contain harmful levels of lead'

The team measured the lead levels in each country-category and calculated the lead intake on the basis of daily consumption.

BBC: US rice imports 'contain harmful levels of lead'

These high lead levels may harm both the mother and developing foetus.

CNN: Calcium for Moms-to-Be