Toward dioxin-free chars: comparative toxicity of biomass valorization pathways under CO2, N2, and hydrothermal conditions.

Impacts of the 2024 flash flood on water quality, pathogenic bacteria and organic contaminant risks in the Albufera Natural Park (Valencia, Spain).

Ophthalmotoxicology of polyhalogenated compounds.

Taizhou City in Zhejiang Province was once one of China's largest e-waste-polluted areas. We assessed the effects of perinatal exposure to multiple heavy metals and dioxins on serum steroid levels in children from this area. We recruited 42 pairs of mothers and infants, collected breast milk and blood samples from the children, and detected dioxins and heavy metals in the breast milk, as well as steroid hormones in the serum. We employed multiple analytical approaches, including multivariable linear regression (MLR) model and Bayesian kernel machine regression (BKMR) models, to investigate the relationship between heavy metals, dioxins, and the serum steroid hormone levels in these children. In a separate exposure model using MLR, total polychlorinated dibenzofurans (PCDFs) (β: -0.930, 95% CI: -1.837, -0.023) and total polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/DFs) (β: -0.578, 95% CI: -1.142, -0.013) were negatively associated with DHEA. Within the MLR mixed exposure model, a negative association was observed between cadmium (Cd) and progesterone (β: -0.225, 95% CI: -0.447, -0.004), while a positive association was found between 2,3,7,8-TeCDD (TCDD) and dehydroepiandrosterone (DHEA) (β: 0.841, 95% CI: 0.196, 1.485). However, based on the BKMR results, these associations were attenuated. Perinatal exposure to heavy metals and dioxins may disrupt sex hormone levels and may have an impact on later reproductive health.

For the past three decades, the U.S. Department of Agriculture (USDA) has conducted surveys of the domestic meat supply every 5 years to determine the temporal trends and current levels of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and non-ortho-polychlorinated biphenyls (no-PCBs), referred to as dioxins. In the 2023–2024 dioxin survey, fat samples from beef (n = 145) and pork (n = 143) along with Siluriform muscle (n = 53) were collected from U.S. slaughter facilities and analysed for 17 PCDD/Fs and 3 no-PCBs. Toxic equivalency factors (TEFs) from 2005 were utilised to calculate the sum-toxic equivalency (sum-TEQ) for all samples for comparison to previous surveys. The sum-TEQs ranged from non-detect (nd) to 2.75 pg TEQ/g lipid for the current survey. Beef, pork, and Siluriform median sum-TEQs (nd = ½ LOD) were 0.150, 0.032, and 0.076 pg TEQ/g lipid or wet weight for Siluriformes, respectively. Declining trends in median concentrations are observed for the surveys over the last 30 years. Statistical analysis of this survey compared to the previous survey, shows significant decreases (p < 0.001) in the median concentrations for the sum-TEQs of PCDD/F and no-PCB for all classes. These temporal declines provide evidence that measures for minimisation of PCDD/F and no-PCB release in meat products have been working.

The treatment of polychlorinated dibenzodioxins and polychlorinated dibenzofurans (PCDD/Fs) in incineration fly ash presents a significant challenge in solid hazardous waste management. This study systematically analyzed the influence mechanisms of multiple factors on the removal efficiency of PCDD/Fs during fly ash pyrolysis. It integrated 4068 datasets conducted between 2010 and 2025 through meta-analysis. Results show that Al2O3, CaO, SiO2, and Cl in fly ash components enhance the removal efficiency by 14.0%, while Fe2O3 (Content greater than 5.7%) exhibits inhibitory effects. Cd and Cr demonstrate a bimodal response pattern: low/high concentrations promote removal, while medium concentrations inhibit it. Process optimization identified the optimal parameter combination as pyrolysis temperatures of 500–900 °C, residence time of 50–90 min, and a gas flow rate greater than or equal to 400 mL/min. A significant negative correlation was observed between the initial dioxin concentration and removal efficiency. This study established a structural equation modeling (SEM) model to describe how metallic and nonmetallic components, fly ash components, and pyrolysis conditions determine removal efficiency. Fly ash composition was confirmed as the most influential factor (total effect = 0.3194), with fixed carbon and ash content being the most reliable indicators. Among pyrolysis conditions, gas conditions (flow rate, gas type) also significantly affected removal efficiency (total effect = 0.2357). Conversely, nonmetallic components and excessively prolonged pyrolysis time (beyond the window) consistently reduced removal efficiency. These findings provide theoretical support for upgrading fly ash pyrolysis processes toward low-carbon and resource-efficient operations.

Dioxin and PCB monitoring in Greek food products during the period 2002-2022 and preliminary assessment of general population exposure through the diet.

Congener-specific accumulation of PCDD/Fs, PCBs, and PBDEs in sheep (Ovies aries) liver and muscle.

The term "dioxins" encompasses a group of chlorinated organic pollutants, including polychlorinated dibenzo-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), which impact human health, affecting immunological, neurological, endocrine, and reproductive systems. Activities like burning fuels, waste incineration, landfill fires, and certain industrial processes are major sources of dioxin emissions. There has been much debate on the quantity of dioxins released by waste incinerators but considerably less debate has been carried out on the dioxin emissions of landfill fires. Thus, this study evaluates dioxin emissions changes in countries that have transitioned from landfill to waste-to-energy (WTE) in a specific period. This study analyzes data from selected countries, including the UK, Austria, Poland, Ireland, Norway, Lithuania, Finland, and China, and applies parametric estimation methods to determine changes in dioxin emissions during the transition from landfill to WTE. The results of this study indicate that reducing landfilling leads to a significant decrease in dioxin emissions. In the studied countries, dioxin emissions decreased in the range of 27% and 94% per mass unit of waste treated by WTE and landfill methods. This reduction emphasizes the potential of WTE to increase environmental sustainability compared to traditional landfilling. Also, it confirms that the reduction of landfill fires is the main factor in the reduction of dioxin emissions. The study's insights may serve as guidance for underdeveloped and developing regions seeking to mitigate dioxins and other pollution through modernized waste treatment infrastructure.

Catalytic oxidation of model compounds for simulating dioxins: A molecular cutting method and kinetic study.

The accumulation and diversity of organic pollutants (OPs) in soil underscore the urgent need for a systematic prioritization method. This study developed a priority organic pollutant scoring system (POPSS) and conducted prioritization of OPs in coal mine soil. The POPSS utilized a weighted integrated scoring system, considering four aspects covering concentration, toxicity, environmental behavior and management feasibility. Sixty-three (63) classes of potential OPs were listed as potential OPs list, based on government documents, investigation reports, and other materials. The OPs were then prioritized and ranked as detailed OPs list. Benzene (B), poly-chlorinated biphenyl 169 (PCB 169), total petroleum hydrocarbon (TPH), Benzo[a]pyrene (BaP), and polychlorinated dibenzo-p-dioxins and Polychlorinated dibenzofurans (PCDD/Fs) occupied the top five scores and were listed as prominent OPs list. From the perspective of OP categories, PCBs, polycyclic aromatic hydrocarbons (PAHs), TPH and PCDD/Fs emerge as noteworthy OPs due to their significantly higher ratings. The characteristics of different indicators of OPs have also been analyzed, revealing the widespread presence of PAHs in coal mine soil, the high bio-accumulation potential and persistence of PCBs, and the noteworthy toxicity of titanate compounds. The POPSS developed in this study can be applied to evaluate the priority of OPs in various types of soil environments and can be used as a reference for governmental policies and environmental legislation in various application scenarios.

Formation pathways, migration characteristics, and inhibition mechanism of polychlorinated dibenzo-p-dioxins and dibenzofurans in hazardous waste incinerators: A comprehensive pilot-scale study.

Dioxin and PCB levels in sea trout with ulcerative disease syndrome.

Atmospheric wet deposition monitoring of PCDD/Fs in an urban site: Fluxes, rain concentrations and washout ratios.

Association between dietary intake estimated levels of PCDD/Fs and human sperm quality.

Persistent organic pollutants (POPs), including polychlorinated biphenyls (PCB), polychlorinated dibenzo-p-dioxins (PCDD), and polychlorinated dibenzofurans (PCDF), are a class of chemical compounds with high persistence that can accumulate in living organisms, mainly in fatty tissues. In addition, exposure to them can cause a wide variety of health problems and adverse effects on humans and wildlife. Therefore, this work aimed to assess the occurrence, distribution, and levels of PCB, PCDD and PCDF in fish samples from the Antioquia region, Colombia. In total, 90 samples of different fish species were evaluated. The levels of the six indicator PCBs were in a range between 26.6 pg·g−1 w.w (1.33 ng·g−1 fat) and 4550 pg·g−1 w.w (236.0 ng⋅g−1 fat), the mean value was 395 pg·g−1 w.w (16.7 ng⋅g−1 fat) and the median was 186 pg·g−1 w.w (8.24 ng⋅g−1 fat). The levels of dioxin-like PCBs were between 3.09 pg·g−1 w.w (0.135 ng⋅g−1 fat) and 567 pg·g−1 w.w (33.9 ng⋅g−1 fat), the mean value was 47.2 pg·g−1 w.w (2.30 ng⋅g−1 fat) and the median was 15.5 pg·g−1 w.w (0.811 ng⋅g−1 fat). The mean and median of the PCB toxic equivalent values were 46.6 fg·TEQ·g−1 w.w and 12.0 fg·TEQ·g−1 w.w, respectively. In all cases, PCDD/PCDF were below the analytical method quantification limits. In summary, PCB and PCDD/PCDF levels in selected fish corresponded to background levels and no hot spots were observed. Finally, this study provided an overview of the current situation regarding the presence of these types of pollutants in the region, which could support future research.Graphical abstract

Pollution from past industrial activities can remain unnoticed for years or even decades because the pollutant has only recently gained attention or been identified by measurements. Modeling the emission history of pollution is essential for estimating population exposure and apportioning potential liability among stakeholders. This paper proposes a novel approach for reconstructing the history of polychlorinated dibenzo-p-dioxin (PCDD) and polychlorinated dibenzofuran (PCDF) pollution from municipal solid waste incinerators (MSWIs) with unknown past emissions. The proposed methodology relies on the search for technical and operational data on the pollution source in archives, the extraction of representative data from the scientific literature, and the use of kinetic models of the formation and decomposition of PCDD/Fs within combustion chambers. This new methodological tool allows to estimate any MSWI’s stack emission and relative profile of seventeen PCDD/F congeners over time. The approach is validated through a case study of an MSWI in Switzerland. The modeled congener profile achieved a Pearson correlation coefficient of 0.98 with measurements in fly ash washwater. Additionally, the simulated soil quantity (1,115–1,419 gTEQ WHO-2005 or 1,283–1,698 gTEQWHO-2022) agrees in order of magnitude with the estimated quantity from measurements (371 gTEQ WHO-2005 or 425 gTEQ WHO-2022).Graphical Supplementary InformationThe online version contains supplementary material available at 10.1007/s00244-025-01150-9.

Investigation of the effect of chlorine in different additives on dioxin formation during high temperature processing of iron ore

The widespread consumption of roasted plantain and fish (Bolle), a common delicacy in Bayelsa State has raised concerns over potential health risks associated with food processing contaminants such as acrylamides, polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs). The roasted plantain and fish are usually prepared by placing the peeled plantain and the dressed fish on a wired gauze and placed over a burning charcoal. The subacute toxicity study of this diet was investigated using twenty adult male rats averagely weighing 117.22 \(\pm\) 4.48 g. The rats were divided into four groups of five rats per group. Group A (Control), was fed with the standard rat chow, Group B; was fed with only the roasted plantain, Group C; was fed with only the roasted fish, and Group D; was fed with a combination of the roasted plantain and fish. The rats were given free access to the feed and portable water ad-libitum throughout the experimental protocol. Body/organ weight data were recorded before and after the completion of the experimental protocol. On day 15th of the experimental protocol, the rats were euthanized and blood specimens were obtained by cardiac puncture for biochemical analysis. The liver, kidney and heart were dissevered instantaneously and weighed. Findings from the study showed that the roasted plantain-fed group had significantly reduced body weight gain, and increased liver and kidney to body weight ratio (p&gt;0.05). The plasma enzyme activity (AST, ALT and ALP) of the plantain-fed group were also significantly increased (p&lt;0.05) while other groups showed non-significant differences (p&gt;0.05) with the control group. The antioxidant status (CAT, SOD and GPx), haematological parameters (RBC, PCV, Hb, MCV, MCH, MCHC and platelet) of the plantain-fed groups were also significantly decreased (p&lt;0.05) while other groups had non-significant changes (p&gt;0.05) when compared to the control group. Malondialdehyde levels in the roasted plantain-fed group were also significantly increased (p&lt;0.05).

ABSTRACT This study aims to identify the occurrence and characteristics of PCDD/Fs in soil and sediment samples from secondary copper and aluminum villages in northern Vietnam using the HRGC/MS system. Additionally, it assesses the impact of PCDD/Fs on human health and the potential ecological risks they pose. The residual concentrations of PCDD/Fs in soil and sediment samples collected from the secondary copper Dai Bai village and secondary aluminum Man Xa village were as follows: 0.37 ± 0.29 ng TEQ/kg d.w. (ranging from 0.06 to 0.63 ng TEQ/kg d.w.); 4.88 ± 0.51 ng TEQ/kg d.w. (ranging from 0.512 to 12.17 ng TEQ/kg d.w.); 11.2 ± 5.31 ng TEQ/kg d.w. (ranging from 5.12 to 15.2 ng TEQ/kg d.w.); and 21 ± 12.7 ng TEQ/kg d.w. (ranging from 0.37 to 31.6 ng TEQ/kg d.w.), respectively. The distribution of PCDD/Fs indicated Octa- and Hepta-CDD/Fs as the dominant congeners with high chlorine content. The TEQ levels of PCDD/Fs in all soil and sediment samples were found to be below the allowable limit according to Vietnamese regulations, with the top contributor being 2,3,4,7,8-PeCDF. Samples collected near the production areas exhibited higher levels of PCDD/Fs compared to those collected farther away. The UNEP toolkit was utilized to determine the permissible dioxin TEQ concentrations suitable for livestock farming. The lifetime average daily doses (LADD) of PCDD/Fs via soil ingestion in Man Xa and Dai Bai were calculated as 0.04 × 10−3 and 1.54 × 10−3 pg TEQ/kg d.w. respectively. The relative cancer risks for humans were estimated at 0.05 × 10−12 and 2.05 × 10−12. Furthermore, the ecological risk assessment method indicates that dioxin in all soil and sediment samples near the aluminum recycling craft village had a negative impact on the ecosystem. In contrast, sediment samples taken away from the aluminum recycling craft village and all sediment soil samples in the bronze casting village did not show negative impacts on the ecosystem.