The presence of polycyclic aromatic hydrocarbons (PAHs) in the fetal environment is a high-priority concern due to the fetus being more sensitive than adults to these ubiquitous xenobiotics. The aim of the present study was to compare the maternal and fetal serum levels of ΣPAHs and their effects on fetal growth in an industrial and an urban area in Southwest Iran. The industrial area was the petrochemical and gas area (PGA) of the Central District of Asaluyeh County and the urban area (UA) was the Central District of Bushehr County, Ninety-nine maternal serum (MS) and 99 cord serum (CS) samples from the PGA and 100 MS and 100 CS samples from the UA were collected during May 2018 to February 2019. The mean concentrations of ΣPAHs were significantly (p < 0.05) higher in the PGA than the UA in both MS (157.71 vs. 93.56 μg/L) and CS (155.28 vs. 93.19 μg/L) samples. Naphthalene (NAP) was the predominant PAH detected in all the studied samples. Significant negative associations were found between birth weight and anthracene (ANT) level in MS (β = −22.917, p = 0.032; weight decrement = 22.917 g for a 1 μg/L increase in ANT); head circumference and chrysene (CHR) level in MS (β = −0.206, p = 0.023; head circumference decrement = 0.206 cm for a 1 μg/L increase in CHR); and birth height and NAP level in CS (β = −0.20, p = 0.005; height decrement = 0.20 cm for a 1 μg/L increase in NAP). Maternal diet had a significant effect on the serum levels of PAHs. The results of this study showed that transmission of PAHs from mother to fetus through the cord blood is an important issue and mothers who live in industrial areas and consume PAH-containing foodstuffs, and their fetuses, are more at risk than those living in a non-industrial urban area.

Pregnant women are widely exposed to organophosphate (OP) pesticides, which are potentially neurotoxicant for the developing fetus. We aimed to identify principal demographic and dietary predictors of OP pesticide exposure among 450 pregnant women participating in the New York University Children’s Health and Environment Study (enrolled 2016–19). Urinary concentrations of six dialkyl phosphate (DAP) metabolites (3 dimethyl (DM) metabolites and 3 diethyl (DE) metabolites) of OP pesticides were determined at three time points across pregnancy. At mid-gestation, the Diet History Questionnaire II was used to assess women’s dietary intake over the past year. Demographic characteristics were obtained using questionnaires and/or electronic health records. We used linear mixed models to evaluate the associations of demographic and food groups with DAP metabolite levels, and partial-linear single-index (PLSI) models to analyze the contribution proportions of food groups to DAP metabolite concentrations and the dose-response relationships between them. We observed that pregnant women in NYC had lower levels of OP pesticide metabolites than pregnant populations in Europe, Asia, and other regions in the U.S. Having lower pre-pregnancy body mass index and being Asian, employed, and single were associated with higher DAP metabolite concentrations. Fruit and grain intakes were associated with higher ∑DM, ∑DE, and ∑DAP levels. ∑DE concentrations increased 9.0% (95% confidence interval (CI) = 1.2%, 17.4%) per two-fold increase in dairy consumption, whereas ∑DE concentrations decreased 1.8% (95%CI = −3.1%, −0.4%) per two-fold increase in seafood consumption. The PLSI model indicated that among the food mixture, fruit and grains were the main food groups contributed to higher levels of ∑DAP, while meat contributed to lower levels of ∑DAP. The contribution proportions of fruit, grains, and meat were 18.7%, 17.9%, and 39.3%, respectively. Our results suggest that fruit, grains, and meat are major dietary components associated with OP pesticide exposure in urban pregnant women.

A prospective cohort study of a Chinese population was conducted to investigate the relationship between prenatal phthalates exposure and maternal hemoglobin or anemia. Based on the Ma'anshan Birth Cohort study, 7 phthalate metabolites were quantified in spot pregnancy urine samples (n = 9263) from 3269 pregnant women during each trimester. The maternal hemoglobin concentrations were obtained from electronic medical records at the same three time points for each participant during pregnancy. Anemia was defined as a hemoglobin concentration below 110 g/L in pregnant women. Repeated measures and trimester-specific analyses were used to estimate the effects of phthalates exposure on maternal hemoglobin and anemia. The prevalence of anemia was 3.6%, 27.0%, and 26.5% during the first, second and third trimester, respectively. Repeated measures analysis showed that hemoglobin concentrations decreased by 0.55, 0.19, 0.57, 0.49, and 0.54 g/L with each 1 ln-transformed concentration increase of MBP, MBzP, MEHP, MEOHP, and MEHHP, respectively. Exposure to MMP, MBP, MEHP, MEOHP, and MEHHP increased the risk of anemia by 1.11-fold, 1.21-fold, 1.20-fold, 1.13-fold, and 1.16-fold, respectively. Trimester-specific regression models stratified by the sample collection time during pregnancy generated consistent results. This is the first study focusing on the effect of prenatal phthalate exposures on hemoglobin or anemia in pregnant Chinese women. We found that prenatal phthalates exposure not only decreased the concentrations of hemoglobin but also showed associations with the prevalence of anemia. Associations appeared stronger for the subsample representing women pregnant with a male fetus than those pregnant with a female fetus. Anemia remains a moderate public health problem in China, and effective measures should be implemented.

Pregnant women and their fetuses represent susceptible populations to environmental contaminants. Exposure to polycyclic aromatic hydrocarbons (PAHs) among pregnant women may contribute to adverse birth outcomes such as preterm birth. Multiple previous studies have assessed airborne sources of PAHs among pregnant women but few have measured urinary PAH metabolites which can capture total exposure through multiple routes. The aim of this study was to bridge this knowledge gap by assessing longitudinal urinary PAH metabolite concentrations over two time points in pregnancy cohorts in Boston (N = 200) and Puerto Rico (N = 50) to better understand exposure distributions throughout pregnancy and how they relate to demographic factors. Urine samples were analyzed for 1-NAP, 2-NAP, 2-FLU, 1-PHE, 2,3-PHE, 4-PHE, 9-PHE, and 1-PYR. Concentrations of 2-NAP, 1-PYR, and 4-PHE were higher in Puerto Rico, while all other metabolites were present in higher concentrations in Boston. In Puerto Rico, intraclass correlation coefficients (ICC) were weak to moderate, ranging from 0.06 to 0.42. PAH metabolite concentrations were significantly higher among younger, heavier (except 1-NAP and 9-PHE), and less educated individuals in Boston only. Consistent significant associations between PAH concentrations and measured covariates were not found in Puerto Rico. Our results suggest that potentially important differences in PAH exposure exist between these two populations. Additionally, our results indicate that multiple urinary measurements are required to accurately assess PAH exposure throughout pregnancy.

Triclosan (TCS) is an organic compound with a wide range of antibiotic activity and has been widely used in items ranging from hygiene products to cosmetics; however, recent studies suggest that it has several adverse effects. In particular, TCS can be passed to both fetus and infants, and while some evidence suggests in vitro neurotoxicity, there are currently few studies concerning the mechanisms of TCS-induced developmental neurotoxicity. Therefore, this study aimed to clarify the effect of TCS on neural development using zebrafish models, by analyzing the morphological changes, the alterations observed in fluorescence using HuC-GFP and Olig2-dsRED transgenic zebrafish models, and neurodevelopmental gene expression. TCS exposure decreased the body length, head size, and eye size in a concentration-dependent manner in zebrafish embryos. It increased apoptosis in the central nervous system (CNS) and particularly affected the structure of the CNS, resulting in decreased synaptic density and shortened axon length. In addition, it significantly up-regulated the expression of genes related to axon extension and synapse formation such as α1-Tubulin and Gap43, while decreasing Gfap and Mbp related to axon guidance, myelination and maintenance. Collectively, these changes indicate that exposure to TCS during neurodevelopment, especially during axonogenesis, is toxic. This is the first study to demonstrate the toxicity of TCS during neurogenesis, and suggests a possible mechanism underlying the neurotoxic effects of TCS in developing vertebrates.

The placenta is an intermediary organ between the female and the developing foetus. Some chemical substances, including the most harmful ones, exhibit the ability to accumulate in or penetrate through the placenta. The aim of the study was to determine the role of the placenta of the Baltic grey seal (Halichoerus grypus grypus) in the transfer of endocrine disrupting compounds (EDCs) - (bisphenol A, 4-tert- octylphenol, 4- nonylphenol), as well as total and organic mercury. 30 placentas were collected from grey seals pupping under human care at the Hel Marine Station in the years 2007–2016. The assays were conducted using the technique of high-preformance liquid chromatography (phenol derivatives) and atomic absorption spectrometry (mercury and selenium). A measurable level of EDCs was indicated in the placentas of grey seals. It was established that the inorganic Hg form was accumulated in the placenta, and that its concentrations were an order of magnitude higher than the concentrations of the organic form, which penetrated to the foetus. Similar observations were made for phenol derivatives - bisphenol A, 4-tert- octylphenol and 4-nonylphenol. For this compound group the placenta was a barrier, but the properties of phenol derivatives suggest the possibility of their penetration through this organ.

Placenta and umbilical cord blood are important media for investigating maternal–fetal exposure to environmental pollutants. Historically hexachlorocyclohexanes (HCHs) were once widely-used in China. In this study, residues of HCHs were measured in placenta and umbilical cord blood samples for 40 women from Beijing. The measured median values of HCHs were 62.0 and 68.8 ng/g fat in placenta and umbilical cord blood, respectively. Concentrations of HCHs in placenta and umbilical cord blood of urban cohort were higher than those of rural group due to enhanced consumption of fish, meat, and milk. Residues of HCHs in placenta were significantly correlated with total food consumption, dietary intake, and maternal age, and could be predicted using the parameters dependent upon ingestion of meat and milk. The transplacental exposure of fetuses to HCHs was revealed by a close association between the residual levels in the paired placenta and the paired umbilical cord blood samples.

Although Polychlorinated biphenyl (PCB) levels are decreased in the environment, the adverse effects of gestational exposure on the mother and offspring cannot be ignored due to the vulnerability of the fetus. In the present study, pregnant Balb/c mice were administered PCB52 (1 mg/kg BW/day) or corn oil vehicle by gavage until parturition. In the dams, PCB52 caused histopathological changes in the liver, higher serum levels of aminotransferase and alanine aminotransferase, and activated apoptosis and autophagy, suggesting hepatotoxicity. Overexpressed indicators of TLR4 pathway were observed in the liver of PCB52-exposed dams, indicated hepatic inflammation. Moreover, PCB52 exposure weakened the intestinal barrier and triggered inflammatory response, which might contribute to the hepatic inflammation by gut-liver axis. In the pups, prenatal PCB52 exposure affected the sex ratio at birth and reduced birth length and weights. Similar to the dams, prenatal PCB52 exposure induced hepatotoxicity in the pups without gender difference. Consistent with the alteration of gut microbiota, intestinal inflammation was confirmed, accompanying the disruption in the intestinal barrier and the activation of apoptosis and autophagy in the PCB52-exposed pups. Intestinal injury might be responsible for hepatotoxicity at least in part. Taken together, these findings suggested that gestational PCB52 exposure induced hepatic and intestinal injury in both maternal and offspring mice by arousing inflammation.

Per- and polyfluoroalkyl substances (PFAS) have been produced and used in a broad range of products since the 1950s. This class, comprising of thousands of chemicals, have been used in many different products ranging from firefighting foam to personal care products and clothes. Even at relatively low levels of exposure, PFAS have been linked to various health effects in humans such as lower birth weight, increased serum cholesterol levels, and reduced antibody response to vaccination. Human biomonitoring data demonstrates ubiquitous exposure to PFAS across all age groups. This has been attributed to PFAS-contaminated water and dietary intake, as well as inadvertent ingestion of indoor dust for adults and toddlers. In utero exposure and breast milk have been indicated as important exposure pathways for foetuses and nursing infants. More recently, PFAS have been identified in a wide range of products, many of which come in contact with skin (e.g., cosmetics and fabrics). Despite this, few studies have evaluated dermal uptake as a possible route for human exposure and little is known about the dermal absorption potential of different PFAS. This article critically investigates the current state-of-knowledge on human exposure to PFAS, highlighting the lack of dermal exposure data. Additionally, the different approaches for dermal uptake assessment studies are discussed and the available literature on human dermal absorption of PFAS is critically reviewed and compared to other halogenated contaminants, e.g., brominated flame retardants and its implications for dermal exposure to PFAS. Finally, the urgent need for dermal permeation and uptake studies for a wide range of PFAS and their precursors is highlighted and recommendations for future research to advance the current understanding of human dermal exposure to PFAS are discussed.

Ambient carbon monoxide (CO) and particulate matters (PMs) are two important air pollutants in urban areas with known impacts on fetuses. Hence, this study measured some biochemistry factors of 200 neonates with birth dates from January 19 to October 12, 2020, including the birth weight and height and the serum levels of ALT, AST, ALP, GGT, and TSH. The Support Vector Machine-fitted land-use regression approach was used to predict the spatio-temporal variability of intra-urban PM 2.5 and CO concentrations by month during the pregnancy period of the cases employing 5 variables of Digital Elevation Model (DEM), slope, and distance from Compressed Natural Gas (CNG) stations, Bus Rapid Transit (BRT) stations, and mines and industries. Spearman correlation analysis (p < 0.05) was performed between the neonate indices and mean monthly PM 2.5 and CO concentrations at the exact residential address of maternal cases and their nearby areas in 250, 500, 1000, 1500, and 2000 m-radius buffer rings. All modeling efforts succeeded in predicting CO and PM 2.5 levels with acceptable adjusted r² values. Northern Isfahan had relatively higher CO and PM 2.5 concentrations due to its adjacency to low-vegetated open lands and its high traffic load as compared to southern areas. The correlation results between the neonate biochemistry indices and mean PM 2.5 and CO concentrations were mostly positive in most buffer rings, especially in the >500 m-radius buffer rings for PM 2.5 and in the 2000 m-radius rings for CO. Although the correlation results of PM 2.5 followed a detectable trend in the buffer rings, the associations between CO and the neonate biochemistry indices differed significantly between the buffer rings. Results showed that increasing mean monthly concentration of CO and PM 2.5 may stimulate further production of liver enzymes while decreasing the birth weight and height.