通过检索国际体育上诉法庭听证会文件，关于瓦利耶娃样本药物浓度及相关专家证词事实如下：

第一，样本浓度为2.1ng/ml。

第二，检测的技术下限为10ng/ml。

第三，专家证言一个运动员口服一片35毫克曲美他嗪后一天，尿样本浓度应该为960-9000ng/ml。2ng/ml 如果是口服摄入，起码是在5到7天前。

第四，瓦利耶娃团队认为由于样本浓度极度低下，存在污染和技术错误的可能性。要求对B样本进行检测。法庭采纳其要求。

相关文字段落拷贝如下：

The concentration of Trimetazidine detected was estimated at 2.1 ng/ mL

single use of a dose of 35mg TMZ leads to a concentration of the substance in a sample a day later between 966 ng/ml 9000 ng/ ml. A concentration of 2 ng/ ml would require a single use of 35 mg a minimum 5 – 7 days before the competition. 

Moreover, the DADC also took into consideration that the Athlete's legal representative disputed the positive results of the Sample alleging that the concentration of 2.1 ng/ml, is well below the technical limit of detection of Trimetazidine , which is 10 ng/ml, and may be a technical mistake of the sample analysis in the laboratory and she confirmed at the hearing the intention to request the analysis of the “ B ” sample.

法庭文件链接：https://int.nyt.com/data/documenttools/court-of-arbitration-for-sport-ruling-on-kamila-valieva/412fe80e6c099377/full.pdf