Ying Guo

Due to their wide application, there is a large amount of residual antibiotics in our environment and food, raising concerns about health risks to children. In this study, 302 primary-school students in Hainan Province, China, were recruited to collect urine samples and questionnaires. The internal exposure levels of sixteen antibiotics and three metabolites in urine were determined by high-performance liquid chromatography–tandem mass spectrometry (HPLC-MS/MS), and the contents of DNA oxidative damage markers, 8-hydroxy-2′-deoxyguanosine (8-OHdG) and lipid peroxidation marker malondialdehyde (MDA), were also measured. Antibiotics and their metabolites were frequently detected, with a total concentration of < LOD-4.58 × 10³ ng/mL. Binary logistic regression analysis revealed that the detection frequency of DFs of antibiotics was associated with animal-derived foods, such as red meat with fluoroquinolones (FQs) (OR = 76.4, 95% CI 1.68–3479), poultry with norfloxacin (NFX) (OR = 6.56, 95% CI 1.08–39.9), and aquatic products with ciprofloxacin (CIP) (OR = 3.96, 95% CI 1.32–11.9). Cumulative risk assessment based on microbial effects showed a hazard index of 3.5 for children, mainly driven by azithromycin (45.6%), oxytetracycline (18.1%), and CIP (33.9%). Multiple linear regression indicated that lipid peroxidation was significantly associated with high quantiles of three antibiotic classes, while DNA oxidation was positively correlated with all antibiotic classes except FQs. These findings indicate that children in Hainan are widely exposed to antibiotics. Although the exposure levels are generally low, chronic low-dose antibiotic exposure may contribute to disease development and oxidative stress damage.

Benzene, toluene, ethylbenzene, and xylene (BTEX) are a common class of volatile organic compounds linked to adverse health outcomes. Although BTEX have been shown to have endocrine disrupting properties, their potential impacts on pubertal development in children remain unclear. In this study, for the first time, we investigated the possible association of BTEX exposure with precocious puberty (PP) and early puberty (EP) in children. We conducted a case–control study that included 246 children diagnosed with PP or EP and a controls category matched for sex and age. Urinary concentrations of seven BTEX metabolites and the oxidative DNA damage biomarker 8-hydroxy-2′-deoxyguanosine (8-OHdG) were measured by high-performance liquid chromatography-tandem mass spectrometry. Compared with the control groups, urinary catechol (1,2-DB) levels were significantly higher in both PP (median: 85.3 vs. 42.4 μg/g creatinine) and EP children (median: 62.0 vs. 48.1 μg/g creatinine). Binary logistic regression models showed that 1,2-DB was positively associated with EP (OR = 1.36, 95% CI: 1.10, 1.69), while trans,trans-muconic acid (MU) was negatively correlated with PP (OR = 0.47, 95% CI: 0.24, 0.92), and PGA was negatively correlated with EP (OR = 0.73, 95% CI: 0.56, 0.93) adjusted for confounders. Stratified analyses showed that the relationship between BTEX metabolites and EP varied by parental education level. Our findings revealed that exposure to BTEX, especially benzene, may influence pubertal timing in children, but there was no relationship between oxidative DNA damage and PP or EP. The biological mechanism of BTEX exposure affecting pubertal development requires further investigation.

Following the sharp increase in global waste generation, heavy metals and metalloids (HMMs) have become a serious threat to workers in the waste recycling industry. However, our understanding of internal exposure levels of HMMs and the relationship between size-resolved particulate matter (PM)-bound HMMs external exposure with internal exposure and oxidative stress among waste recycling workers are limited. Therefore, we collected first morning void urine samples from 20 participants and size-resolved indoor PM₁₀ samples at least 45 consecutive days. We then detected 21 urinary HMMs, PM₁₀-bound HMMs and oxidative stress biomarkers (OSBs) of DNA (8-hydroxy-2′-deoxyguanosine [8-OHdG]) and lipids [malondialdehyde (MDA)]. The intraclass correlation coefficients for most HMMs and OSBs ranged from fair to excellent. Linear mixed model analysis showed that urinary HMMs were predominantly affected by warehouse PM_1.1–2.1 and PM_3.3–4.7 HMM inhalation (p < 0.05). Participant 8-OHdG levels were correlated with PM_0.43–10 HMM inhalation, particularly in the ranges of PM_0.43–0.65, PM_4.7–5.8, and PM_9.0–10, with every unit increase in the ln-transformed average daily intake (ADI) generating a 4.30–28.0% increase in urinary 8-OHdG (p < 0.05). Furthermore, MDA levels were generally correlated with PM_0.43–2.1 HMM inhalation (p < 0.05), especially in the PM_0.43–0.65 range, with each unit increase in the ln-transformed ADI generating a 8.5–24.1% increase in urinary MDA. This study reveals the fair to excellent long-term reproducibility of urinary HMM and OSBs and the association between high-level PM-bound HMM exposure and early health impairment for an actual working environment.

Phthalic acid esters (PAEs), a class of synthetic semi-volatile organic compounds, are extensively incorporated into decorative materials. However, their specific occurrence, migration behaviors, and environmental impact on these materials—which comprise the largest surface areas in residential settings—remain insufficiently understood. This study investigated the distribution, emission dynamics, and environmental burdens of PAEs in flooring commonly used in Chinese households. The results showed that PAEs are widespread in flooring, with total concentrations ranging from 1220 to 166,000 ng/g (14,100 ng/g, median value). Solid wood flooring (55,900 ng/g) exhibited significantly higher PAE levels compared to engineered flooring (22,600 ng/g) and laminate flooring (4000 ng/g) (p < 0.05). Migration experiments revealed that solid wood flooring tended to continuously release PAEs, laminate flooring showed a pronounced capacity for PAE absorption, and engineered flooring exhibited both release and absorption behaviors. The initial PAE concentration is the dominant factor influencing migration rates, while the flooring type and substrate density also contribute to varying degrees. The estimated environmental burdens of PAEs resulting from flooring in newly renovated Chinese households ranged from 3.63 × 10⁹ ng to 3.45 × 10¹¹ ng, with a median value of 1.23 × 10¹⁰ ng. Households in the eastern and southwestern regions exhibited the highest PAE burdens, while the southern region showed the lowest. Socioeconomic factors such as residential floor area, number of rooms, household income, and renovation budget significantly influenced the environmental burden of PAEs derived from flooring.