proximity of blood

Marriages in proximity of blood are forbidden by the law.

法律规定禁止近亲结婚.

proximity of blood is to be avoided in marriage.

血源相近，在婚姻中是要避免的。

The United States Centers for Disease Control and Prevention used to refer to that as a "level of concern," but it now says there is no safe blood level in children.Levels of heavy metal in samples correlated with proximity to the smelting plant.

美国疾病控制和预防中心（Centers for Disease Control and Prevention）曾经称那是“令人担忧的水平”，但现在他们认为并不存在儿童安全血浓度指标。样本中的重金属水平和冶炼厂的距离是相关的。