Environmental Health最新文献

Background: Exposure to phthalates and non-phthalate plasticizers as well as bisphenols may be relevant to the development of behavioural symptoms in childhood with sex-specific effects, although the results of existing studies are not consistent. The aim of the study was to evaluate the cross-sectional association between childhood exposure to these compounds and behavioral outcomes in the REPRO_PL cohort (Poland).

Methods: Behavioral assessments were performed at the age of 7-9 years by parents using the Strengths and Difficulties Questionnaire (SDQ). HPLC-MS/MS was used for the quantification of BPA and 21 phthalate metabolites corresponding to 11 phthalate compounds (n = 400) and their replacement alternatives BPF, BPS, three metabolites of diethylhexyl terephthalate (DEHTP) and three metabolites of di-isononyl-cyclohexane-1,2-dicarboxylate (DINCH) (n = 150). Multivariable linear regression models accounting for sex-specific effects as well as sex-adjusted models were applied, using both separate models for each metabolite (or sum of metabolites) and joint models. In addition, mixtures models adjusted by the three chemical groups studied were also performed.

Results: Median concentrations of several phthalate metabolites and bisphenols were of 42 µg/L (MEP), 4.5 µg/L (MMP), 3.5 µg/L (ΣDiDP), 2 µg/L (BPA) and 1 µg/L (BPF). For ΣDEHTP and ΣDINCH, the median concentrations were 35 µg/L and 3.1 µg/L, respectively. Exposure to phthalates was related to behavioral problems in girls, and bisphenols and DEHTP in boys. Among girls, DiBP was associated with mental health problems (total difficulties: β = 4.84; 95% CI 0.72;8.96, emotional: β = 2.14; 95% CI 0.33;4.0, hyperactivity/inattention: β = 2.52; 95% CI 0.55;4.49, externalizing behavior: (β = 2.95; 95% CI 0.36;5.53) and DiDP with hyperactivity/inattention scores (β = 2.46; 95% CI 0.30;4.63). BPF was associated with emotional problems and internalizing behavior among boys in both main and sensitivity models (main model: β = 1.03; 95% CI -0.16;2.21 and β = 1.71; 95% CI -0.14;3.56 respectively).

Conclusions: This study shows that children's exposure to several replacement compounds of BPA and phthalates, such as BPF and DEHTP, are associated with adverse effects on school-age children's behavior, with a divergent sex-specific effect. In any case, mixture models did not provide any further insight on the aforementioned cross-sectional associations and further methodological approaches are needed to explore adverse neurodevelopmental outcomes in children and teenagers.

Objectives: In the context of global warming and escalating urbanization, occurrences of extreme ozone (EO) and heatwave (HW) events are increasingly frequent. However, studies on the impact of consecutive extreme ozone and heatwave (EO-HW) events on hospitalizations for neurological disorders (ND) and related economic burdens remains limited. Our study aimed to explore the impacts of these events on ND hospitalizations, length of stay, and related costs, with a specific focus on quantifying the impacts of consecutive extreme events of varying durations.

Methods: Time-series analysis was performed to investigate the relationships between consecutive O₃ and HW events of varying durations and the number of hospitalizations, length of stay, and hospitalization costs for ND, employing a quasi-Poisson distributed‑lag non‑linear model (DLNM). In addition, we further identified potential high-risk groups by age and gender stratification.

Results: Exposure to EO-HW events were associated with an increased risk of hospitalization for ND, with this risk persisting from lag 1 day (1.097, 95% CI: 1.005,1.198) to lag 4 days (1.071, 95% CI: 1.004,1.139). Significant associations were particularly evident in male (highest RR value 1.092, 95% CI: 1.016,1.173) and aged < 65 years (highest RR value 1.124, 95% CI: 1.008,1.254). Furthermore, exposure to EO-HW events were found to result in longer length of stay and higher hospitalization costs compared to exposure to HW events alone.

Conclusions: Consecutive EO-HW events significantly increase the risk of hospitalization and the economic burden of ND. Local authorities should consider incorporating early warning information and public health interventions for consecutive extreme weather into existing early warning systems. Neglecting to do so will likely result in higher associated illness rates and economic burdens.

Background: Environmental exposures, such as pesticides, during pregnancy have been associated with several adverse pregnancy outcomes, including miscarriage and shorter gestational length at birth. However, their relationship with gestational diabetes (GDM) is uncertain. The objective of this study was to analyze first-trimester urinary herbicide concentrations for their associations with GDM.

Methods: This was a nested case-control study analysis of the Nulliparous Pregnancy Outcomes Study- Monitoring Mothers-to-be (nuMoM2b) study. The study included participants at the three midwestern study sites. We analyzed individuals according to whether they developed GDM. Urinary herbicide concentration at the upper quartile was the exposure of interest. To assess the association of first-trimester urine glyphosate and metabolites with GDM, conditional logistic regression was used for matched pairs models. To test whether the association of herbicides with GDM was modified by BMI, an interaction term of herbicide (dichotomous variable) * BMI was included.

Results: The 118 cases of nuMoM2b participants with GDM were matched with 118 randomly selected age-matched controls who had no adverse pregnancy outcomes. Participants with GDM were less likely to be Non-Hispanic White (26.3% vs. 40.7%; p = 0.02), had a higher mean BMI (30.7 ± 8.3 vs. 26.1 ± 6.3; p < 0.01), and were less likely to have graduated from college (55.1% vs. 72.0%; p = 0.007). Glyphosate concentrations were above the limit of detection (LOD) in 93.6% of analyzable samples. In the adjusted conditional logistic regression for the matched pairs model, participants with glyphosate in the upper quartile had significantly higher odds of having GDM (odds ratio [OR] 3.27, 95% confidence interval [CI] 1.04-10.3), with the OR of 1.23 (95% CI 1.02-1.47) for the interaction with BMI. Compared to participants with BMI < 25 kg/m², the adjusted odds of GDM for participants with obese BMI (≥ 30 kg/m²) was elevated (OR 8.52, 95% CI 1.27-57.2).

Conclusion: First trimester urinary glyphosate concentrations were associated with development of GDM, and the magnitude of this association increased at higher BMI.

Trial registry: NCT01322529.

Background: Exposure to heat leads to physiological and cognitive impairments that increase the risk of workplace injuries. This study estimates the number and proportion of work injuries reported to the United States Occupational Safety and Health Administration (OSHA) that can be attributed to heat exposure. These estimates contribute to the calculation of the benefits of standards, policies, and programs that reduce workplace exposure to extreme heat.

Methods: We analyzed all 2023 injury cases reported to OSHA's Injury Tracking Application by establishments with 100 or more employees, primarily in high-hazard industries. Each injury was geocoded and matched with high-resolution weather data for the specific injury date. Using a case-crossover design, we compared heat index on each injury day (case) with matched non-injury control days for the same worker. Conditional logistic regression was applied separately for summer-only and year-round periods with a non-linear term for heat index to estimate the odds ratios for injury occurrence. We additionally examined heat-injury patterns by industry sectors and in states with/without workplace heat standards.

Results: The odds of work injury increased non-linearly with a rising heat index: the pooled national estimate showed a clear upward trend starting around 85°F and accelerating above 90°F. Our results were consistent across nearly all industry sectors, including those that are predominantly indoors. Using a heat index of 80°F as reference, odds ratios (OR) of injuries at or above 90°F, 100°F and 110°F were 1.03 (95% confidence intervals [CI]: 1.02, 1.04), 1.10 (1.07, 1.13), and 1.20 (1.13, 1.26), respectively. At a heat index of 110°F or higher, the odds increased by 22% in states without occupational heat rules (OR=1.22; 1.15,1.29) versus 9% in states with rules (OR=1.09; 0.84, 1.41), suggesting a protective effect, although confidence intervals overlapped. Overall, we estimate 1.18% (95% empirical CI: 0.92%, 1.45%) of all injuries were attributable to heat exposure on days exceeding a heat index of 70°F.

Conclusion: Heat exposure increases the overall risk of work injury, an effect consistent across nearly all major industries.

The World Health Organization (WHO) commissioned 12 systematic reviews (SR) and meta-analyses (MA) on health effects of exposure to radiofrequency electromagnetic fields (RF-EMF). The health outcomes selected for those reviews (cancer, electromagnetic hypersensitivity, cognitive impairment, birth outcomes, male fertility, oxidative stress, and heat-related effects) were based on a WHO-conducted international survey. The SR of the studies of cancer in laboratory animal studies was the only one that did not include a MA, because those authors considered it inappropriate due to methodological differences among the available studies, including differences in exposure characteristics (carrier frequency, modulation, polarization), experimental parameters (hours/day of exposure, duration of exposure, exposure systems), and different biological models. MAs in all the other SRs suffered from relatively few primary studies available for each MA (sometimes due to excessive subgrouping), exclusion of relevant studies, weaknesses in many of the included primary studies, lack of a framework for analyzing complex processes such as those involved in cognitive functions, and/or high between-study heterogeneity. Due to serious methodological flaws and weaknesses in the conduct of the reviews and MAs on health effects of RF-EMF exposure, the WHO-commissioned SRs cannot be used as proof of safety of cell phones and other wireless communication devices. However, the animal cancer SR, which was rated as "high certainty of evidence" for heart schwannomas and "moderate certainty of evidence" for brain gliomas, provided quantitative information that could be used to set exposure limits based on reducing cancer risk. The multiple and significant dose-related adverse effects found in the SRs on male fertility and pregnancy and birth outcome should also serve as the basis for policy decisions to lower exposure limits and reduce human reproductive risks. The report of harmful effects (e.g., cancer, reproductive toxicity, etc.) at doses below the adverse health effect threshold claimed by ICNIRP demonstrates that current exposure limits to RF-EMF, which were established by applying arbitrary uncertainty factors to their putative adverse threshold dose, lack scientific credibility.

Background: Developmental neurotoxicity (DNT) is a well-established hazard of methylmercury (MeHg) exposure. Past research on MeHg has highlighted DNT tests of language/verbal function (in particular the Boston naming test (BNT)) as an important aspect of MeHg toxicity.

Methods: We conducted a meta-analysis based on a recent systematic review of MeHg neurodevelopmental dose-response cohort studies published 1998-2025 that reported similarly normed tests of language/verbal function. Meta-analyses were based on recent studies using maternal blood biomarkers or cord blood biomarkers converted into maternal blood biomarkers.

Results: For the BNT with or without cues, analysis (based on 2 studies (3 populations)) results were adverse, but not statistically significant. For the similarly normed language/verbal tests, decrements were statistically significant [-0.0085 95% (-0.0167; -0.0003) per MeHg µg/L maternal blood (based on eight studies)]. Results of a fill and trim sensitivity analysis were similar in the size of the effect to the original results. The two studies with sex-specific results indicated that boys appeared to be more sensitive to MeHg-related language/verbal function decrements when compared with girls.

Conclusions: Although most of the individual study results of language/verbal function were not statistically significant, the meta-estimate showed a statistically significant decrement in language/verbal function in children due to prenatal MeHg exposure.

Background: Extensive academic research has documented the tobacco industry's manipulation of science. Recently, scholars have begun examining the sugar industry's use of similar tactics to downplay sugar's role in obesity, diabetes, cardiovascular disease, and tooth decay. Archival records show sugar-industry-funded scientists criticized evidence linking sugar to these harms and deflected attention to other risk factors. Sugar's connection to tooth decay has been the most difficult harm for the industry to deny. Evidence is emerging that the industry turned to promoting fluoride as the solution to tooth decay thereby averting calls for reducing sugar consumption. Newly accessible sugar and dental industry documents enable investigation into whether fluoride research was manipulated to deflect from sugar's role in tooth decay, and later to defend fluoride when evidence of fluoride's own harmful effects arose.

Method: Internal documents from sugar and dental organizations were examined and compared to the published scientific record. The Industries Documents collection at the University of California San Francisco was the main source of records. Analysis was in the context of the current understanding of how vested interests manipulate science to defend their products.

Results: Records dating back to the 1930s demonstrate the sugar industry, sometimes in cooperation with dental interests, exaggerated fluoride's effectiveness and downplayed safety concerns. The sugar industry's science manipulation campaign preceded the better-known tobacco industry campaign defending cigarettes. Key leaders of the sugar industry's campaign transferred to the tobacco industry, which then adopted many of the sugar industry's tactics and financed research from some of the same sugar-conflicted scientists. Currently, a prominent safety issue with fluoride is developmental neurotoxicity. Evidence indicates that researchers with undisclosed conflicts of interest with sugar and allied industries produced biased reviews downplaying this risk.

Conclusion: Recently available records reveal a long history of the sugar industry distorting fluoride science. Many of the sugar industry's tactics were later adopted by the tobacco industry and mirrored by industries involved in asbestos, lead, pesticides, climate change denial, and others. Researchers and policymakers should be aware of the distorted scientific record regarding fluoride effectiveness and toxicity.