The relationship between bisphenol A and phthalates with precocious puberty in Vietnamese children

OBJECTIVES

This study is aimed to explore the correlation between bisphenol A (BPA) and phthalates, including diethylhexylphthalate (DEHP) and dibutylphthalate (DBP), and precocious puberty (PP).

METHODS

A case-control study was conducted in Ho Chi Minh City, Vietnam, from November 2021 to April 2022, involving 250 children, with 124 of them diagnosed with PP and 126 serving as controls. We assessed the levels of urinary BPA, DEHP, and DBP in all participants and examined their association with the risk of PP.

RESULTS

BPA was detected in 11.3 % of PP cases but was not found in any individuals in the control group (p<0.001). Diethylhexylphthalate metabolite (MEHP) was not detected in any of the samples. Positive urinary results for dibutylphthalate metabolite (MBP) were observed in 8.1 % of PP cases and 2.4 % in the control group, with an odds ratio of 3.6 (95 % confidence interval: 0.97-13.4, p=0.03).

CONCLUSIONS

The PP group exhibited a higher prevalence of positive urinary BPA and DBP levels compared to the control group.

Biomonitoring of Phthalates, Bisphenols and Parabens in Children: Exposure, Predictors and Risk Assessment

Exposure to emerging contaminants, such as phthalates, bisphenols and parabens in children has been associated with possible neurodevelopment and endocrine alterations. In the present study, the biomonitoring of biomarkers in children (5–12 years old) from the Valencia Region (Spain) have been implemented using urines from the BIOVAL program. More than 75% of the children studied (n = 562) were internally exposed (>LOQ) to bisphenols and parabens, and the whole population assessed (n = 557) were exposed to at least one phthalate. The geometric means (GM) of the concentrations of bisphenol A, methyl paraben and propyl paraben were 0.9, 1.4 and 0.39 ng/mL, respectively. Regarding phthalates, monoethyl phthalate GM was 55.0 ng/mL and diethyl hexyl phthalate (as the sum of five metabolites) GM was 60.6 ng/mL. Despite the studied population being widely exposed, the detection frequencies and concentrations were in general lower than in previous studies involving children in Spain and in other countries in recent years. Furthermore, the risk assessment study concluded that the internal exposure to phthalates, bisphenols and parabens is lower than the guidance values established, and, therefore, a health risk derived from the exposure to these compounds in the studied population is not expected.

Targeted and suspect screening of plasticizers in house dust to assess cumulative human exposure risk

Indoor dust is an important exposure route to anthropogenic chemicals used in consumer products. Plasticizers are common product additives and can easily leach out of the product and partition to dust. Investigations of plasticizers typically focus on a subset of phthalate esters (PEs), but there are many more PEs in use, and alternative plasticizers (APs) are seeing greater use after recognition of adverse health effects of PEs. In this study we use full scan high resolution mass spectrometry for targeted and suspect screening of PEs and APs in house dust and to assess the potential risk of human exposure. House dust samples from Eastern Slovakia were investigated and concentrations of ∑₁₂PEs and ∑₅APs ranged 12-2765 μg/g and 45-13,260 μg/g, respectively. APs were at similar levels to PEs, indicating common usage of these compounds in products in homes. Evaluation of individual compound toxicity combined with human intake via dust ingestion suggested PEs are of lower priority compared to semivolatile organic compounds such as polychlorinated biphenyls due to their lower toxicity. However, cumulative risk assessment (CRA) is a more appropriate evaluation of risk, considering the presences of many PEs in dust and their similar toxic mode of action. CRA based on median toxicity reference values (TRVs) suggested acceptable risks for dust ingestion, however, the wide range of literature-derived TRVs is a large uncertainty, especially for the APs. Use of newer TRVs suggest risk from dust ingestion alone, i.e. not even considering diet, inhalation, and dermal contact. Additionally, screening of full-scan instrumental spectra identified a further 40 suspect PE compounds, suggesting the CRA based on the 12 target PEs underestimates the risk.