Covaci Adrian, Voorspoels Stefan, Thomsen Cathrine, van Bavel Bert, Neels Hugo
Toxicological Center, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium.
Sci Total Environ. 2006 Jul 31;366(1):361-6. doi: 10.1016/j.scitotenv.2006.03.006. Epub 2006 Apr 19.
The human exposure to persistent organic pollutants (POPs) is conveniently assessed through analysis of blood serum or plasma and the POPs concentrations are traditionally expressed on a lipid weight basis. Enzymatic determinations of total lipid (TL) content in serum, which imply the measurement of individual lipid classes, such as triglycerides (TG), cholesterol (CHOL) and phospholipid (PL), use small amounts of serum/plasma (<100 microl). These have also become a more precise and less laborious alternative for the gravimetric lipid determinations which were preferred in the past. However, PL are not routinely measured in most clinical laboratories and therefore, TL values are often predicted from formulas based on measurements of only TG and CHOL. In the present study, a large data set (n=483) from Belgian, Swedish and Norwegian populations was used to compute a new formula for TL [TL=1.33TG+1.12CHOL+1.48 (g/l)] by means of multiple linear regression. A very good correlation (r=0.949, p<0.001) was found between TL values calculated with the proposed formula and TL values obtained by summation of TG, CHOL and PL. Statistically different values of TL were computed when different previously published formulas were compared, which can have a strong influence on the calculation of lipid-normalized concentrations of POPs. Nevertheless, TL values derived using a mathematical formula which includes only TG and CHOL will be less accurate than TL values obtained by summation of TG, CHOL and PL, which should be the calculation method of choice if PL measurements are available.
通过分析血清或血浆可以方便地评估人体对持久性有机污染物（POPs）的暴露情况，并且传统上POPs浓度是以脂质重量为基础表示的。血清中总脂质（TL）含量的酶法测定涉及对甘油三酯（TG）、胆固醇（CHOL）和磷脂（PL）等单个脂质类别的测量，使用少量血清/血浆（<100微升）。这些方法也已成为过去首选的重量法脂质测定的一种更精确且更省力的替代方法。然而，大多数临床实验室并不常规测量PL，因此，TL值通常根据仅基于TG和CHOL测量的公式来预测。在本研究中，使用来自比利时、瑞典和挪威人群的一个大型数据集（n=483），通过多元线性回归计算出一个新的TL公式[TL = 1.33TG + 1.12CHOL + 1.48（克/升）]。用所提出的公式计算的TL值与通过TG、CHOL和PL总和获得的TL值之间发现了非常好的相关性（r = 0.949，p<0.001）。当比较不同的先前发表的公式时，计算出的TL值在统计学上存在差异，这可能对POPs脂质标准化浓度的计算有很大影响。然而，使用仅包括TG和CHOL的数学公式得出的TL值将不如通过TG、CHOL和PL总和获得的TL值准确，如果可以进行PL测量，后者应该是首选的计算方法。
