Esters of phthalic acid (phthalates), mainly used as plasticisers, are well-known ubiquitous contaminants of the environment. Humans can be exposed to these chemicals through various pathways (mainly ingestion, dermal absorption or inhalation). After entering the human body, phthalates are rapidly metabolised and excreted via urine. Due to the adverse effects of some phthalates on human health (disruption of the endocrine system and carcinogenicity), they are nowadays being replaced with less harmful substitutes such as di-iso-nonyl cyclohexane-1,2-dicarboxylate (DINCH). The aim of this study was to evaluate concentrations of 18 phthalate and 4 DINCH metabolites in urine samples collected from mothers and their newborns living in 2 locations of the Czech Republic (2016–2017). Sample preparation required only enzymatic hydrolysis and dilution of the hydrolysed sample with methanol. Target compounds were identified and quantified using ultra-high performance liquid chromatography coupled with tandem mass spectrometry (UHPLC–MS/MS). The validated method (recovery 60–126%, repeatability 1–14%, limits of quantification 0.15–0.40 ng/mL urine) was used for the analysis of 315 paired urine samples collected from mothers and their newborns. The overall concentration of target analytes was 2 × lower in urine samples collected from newborns compared to their mothers. Monobutyl phthalate (MBP) was the analyte with the highest concentrations (median 22.1 ng/mL in the mothers′ urine samples; median 21.6 ng/mL in the newborns′ urine samples), followed by mono-iso-butyl phthalate (MiBP) and monoethyl phthalate (MEP). A marked difference between samples from both locations was observed in the concentrations of target analytes in newborns, suggesting that the childcare products used in one of the hospitals might have caused this difference. Primary metabolite of DINCH, MINCH, was not found in any of the tested samples and the secondary metabolites of DINCH (OH-, oxo- and cx-MINCH) were present in only 22–23% of the measured samples collected from mothers and in 4–6% of the urine samples collected from their children at relatively low levels. Similar studies abroad reported MEP to be present at the highest levels whilst our study identified MBP as the most abundant. This result could indicate different exposure sources of phthalates in the Czech population compared to other countries, which should be further investigated.

邻苯二甲酸酯（邻苯二甲酸酯）主要用作增塑剂，是众所周知的普遍存在的环境污染物。人类可以通过各种途径（主要是摄入、皮肤吸收或吸入）接触这些化学物质。进入人体后，邻苯二甲酸酯会迅速代谢并通过尿液排出体外。由于某些邻苯二甲酸酯对人类健康的不利影响（内分泌系统的干扰和致癌性），它们现在正被危害较小的替代品所取代，例如二异壬基环己烷-1,2-二羧酸酯 (DINCH)。本研究的目的是评估从居住在捷克共和国 2 个地点的母亲及其新生儿收集的尿液样本中 18 种邻苯二甲酸酯和 4 种 DINCH 代谢物的浓度（2016-2017 年）。样品制备只需要酶水解和用甲醇稀释水解样品。使用超高效液相色谱与串联质谱联用 (UHPLC-MS/MS) 对目标化合物进行鉴定和定量。经验证的方法（回收率 60–126%，重复性 1–14%，定量限 0.15–0.40 ng/mL 尿液）用于分析从母亲及其新生儿收集的 315 份配对尿液样本。与母亲相比，新生儿尿液样本中目标分析物的总浓度低 2 倍。邻苯二甲酸单丁酯 (MBP) 是浓度最高的分析物（母亲尿液样本中的中位数为 22.1 ng/mL；新生儿尿液样本中的中位数为 21.6 ng/mL），其次是邻苯二甲酸单异丁酯 (MiBP) 和邻苯二甲酸单乙酯 (MEP)。在新生儿的目标分析物浓度方面观察到来自两个地点的样本之间存在显着差异，这表明其中一家医院使用的儿童护理产品可能导致了这种差异。DINCH 的初级代谢物 MINCH 在任何测试样品中均未发现，DINCH 的次级代谢物（OH-、氧代-和 cx-MINCH）仅存在于从母亲收集的测量样品中的 22-23% 中。从他们的孩子那里收集的尿液样本中有 4-6% 的水平相对较低。国外的类似研究报告 MEP 含量最高，而我们的研究确定 MBP 含量最高。这一结果可能表明与其他国家相比，捷克人口中邻苯二甲酸酯的不同暴露来源，应进一步调查。