Division of Occupational and Environmental Medicine, Department of Laboratory Medicine, Lund University, Lund, Sweden; Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA, United States.
Department of Food Safety, Norwegian Institute of Public Health, Oslo, Norway.
Environ Res. 2023 Feb 15;219:115096. doi: 10.1016/j.envres.2022.115096. Epub 2022 Dec 16.
Little is known about how PFAS concentrations in human milk change over the course of lactation, although this is an important determinant of cumulative infant exposure from breastfeeding.
To estimate changes in PFAS concentrations in human milk over the course of lactation in a population with a wide range of exposure from background-to high-exposed.
We measured PFAS concentrations in colostrum and mature milk samples from women in the Ronneby Mother-Child Cohort. For each PFAS, we estimated the change in concentration from colostrum collected 3-4 days postpartum to mature milk collected 4-12 weeks postpartum using linear mixed-effects models. We evaluated whether this estimated change varied by quartiles of colostrum concentrations. In a subset of mothers with at least three mature milk samples, we estimated the change in concentration per month over the first eight months of lactation.
Our study included 77 mother-child pairs, of whom 74 had colostrum and initial mature milk samples and 11 had three or more repeated samples. The concentration change from colostrum to mature milk varied by PFAS. While PFOS increased by 21% (95% CI: 8.9, 35), PFOA decreased by 17% (95% CI: -28, -3.5) and PFHxS decreased by 12% (95% CI: -24, 3.3). In addition, PFAS concentrations tended to increase in women with lower colostrum levels, but decreased or remained the same in women with high colostrum concentrations. When we estimated changes over the course of lactation, we found that PFOA concentrations decreased the most (-12% per month; 95% CI: -22, -1.5), whereas PFHxS and PFOS showed small nonsignificant decreases.
Models for cumulative infancy exposure from breastfeeding need to account for differences in concentration trajectories by PFAS and possibly by maternal exposure level. Additional research is needed to evaluate the relative exposure from breastfeeding vs prenatal exposure, especially in highly exposed communities where breastfeeding guidance is urgently needed.
尽管人乳中 PFAS 浓度的变化是母乳喂养期间婴儿累积暴露的重要决定因素，但人们对此知之甚少。
在一个背景至高暴露人群中，估计人乳中 PFAS 浓度在哺乳期的变化。
我们测量了罗尼比母婴队列中妇女的初乳和成熟乳样本中的 PFAS 浓度。对于每种 PFAS，我们使用线性混合效应模型估计从产后 3-4 天收集的初乳到产后 4-12 周收集的成熟乳中浓度的变化。我们评估了这种估计的变化是否因初乳浓度四分位数的不同而有所不同。在至少有三个成熟乳样本的母亲亚组中，我们估计了头 8 个月母乳喂养期间每月的浓度变化。
我们的研究包括 77 对母婴，其中 74 对有初乳和初始成熟乳样本，11 对有三个或更多重复样本。从初乳到成熟乳的浓度变化因 PFAS 而异。虽然全氟辛烷磺酸（PFOS）增加了 21%（95%CI：8.9，35），但全氟辛酸（PFOA）减少了 17%（95%CI：-28，-3.5），并且五氟己基磺酸（PFHxS）减少了 12%（95%CI：-24，3.3）。此外，PFAS 浓度在初乳水平较低的女性中趋于增加，但在初乳浓度较高的女性中减少或保持不变。当我们估计哺乳期的变化时，我们发现 PFOA 浓度下降最多（-12%/月；95%CI：-22，-1.5），而 PFHxS 和 PFOS 则显示出较小的非显著下降。
母乳喂养期间婴儿累积暴露的模型需要考虑到 PFAS 浓度轨迹的差异，并且可能还需要考虑到母体暴露水平的差异。需要进一步研究评估母乳喂养与产前暴露的相对暴露，特别是在急需母乳喂养指导的高暴露社区。
