Effects on child and adolescent health of climate change mitigation policies: A systematic review of modelling studies.

There is a growing body of modelling evidence that demonstrates the potential for immediate and substantial benefits to adult health from greenhouse gas mitigation actions, but the effects on the health of younger age groups is largely unknown. We conducted a systematic review to identify the available published evidence of the modelled effects on child and adolescent health (≤18 years of age) of greenhouse gas mitigation. We searched six databases of peer-reviewed studies published between January 1, 1990 and July 27, 2022, screened 27,282 original papers and included 23 eligible papers. All included studies were set in high- and middle-income countries; and all studies modelled the effects of interventions that could mitigate greenhouse gas emissions and improve air quality. Most of the available evidence suggests positive benefits for child and adolescent respiratory health from greenhouse gas mitigation actions that simultaneously reduce air pollution (specifically PM2.5 and nitrogen dioxide). We found scant evidence on child and adolescent health from regions more vulnerable to climate change, or on mitigation interventions that could affect exposures other than air pollution.

Estimation of Anaerobic Debromination Rate Constants of PBDE Pathways Using an Anaerobic Dehalogenation Model.

This study aims to estimate anaerobic debromination rate constants (km) of PBDE pathways using previously reported laboratory soil data. km values of pathways are estimated by modifying a previously developed model as Anaerobic Dehalogenation Model. Debromination activities published in the literature in terms of bromine substitutions as well as specific microorganisms and their combinations are used for identification of pathways. The range of estimated km values is between 0.0003 and 0.0241 d-1. The median and maximum of km values are found to be comparable to the few available biologically confirmed rate constants published in the literature. The estimated km values can be used as input to numerical fate and transport models for a better and more detailed investigation of the fate of individual PBDEs in contaminated sediments. Various remediation scenarios such as monitored natural attenuation or bioremediation with bioaugmentation can be handled in a more quantitative manner with the help of km estimated in this study.

PCBs in sludge: development of a practical extraction procedure and its application in an urban water resource recovery facility.

Sludges originating from water resource recovery facilities act as a sink for various contaminants including polychlorinated biphenyls (PCBs). Investigation of such pollutants provides detailed information about the pollutant burden of the region from which incoming wastewater is derived. However, the current extraction methods for PCBs in wastewater and sludge are both time- and solvent-consuming. Therefore, the purposes of this study were to develop a practical PCB extraction procedure and to monitor PCB levels in sludge originating from an urban water resource recovery facility (WRRF). Procedure applicability was shown by comparing the extraction results of certified reference materials with that of Soxhlet and by checking surrogate recovery. Diethyl ether, hexane, and hexane:acetone mixture were evaluated as the PCB extraction solvent; hexane was the most efficient solvent with the recovery results (89 to 102%) in an acceptable range of 70 to 130%. The PCB concentrations of the WRRF sludges were in the range of 3.6 ± 0.3 to 64.4 ± 9.3 µg/kg dry matter.

Apportionment of PCB sources near a transformer maintenance and repair facility in Ankara, Turkey.

The concentration and major sources of polychlorinated biphenyls (PCBs) were evaluated in the sediments from a special environmental protection area located near a transformer maintenance and repair facility (TMRF) in Ankara, Turkey. ∑PCB concentrations analyzed on Aroclor and congener basis (seven indicator congeners) ranged from 0.1 to 84.2 and 0.1 to 21.7 ng/g dry weight, respectively. Results show that higher total PCB concentrations were localized around one of the drainage channels of the TMRF. Identity and contribution of PCB sources were predicted using a chemical mass balance (CMB) based receptor model. The CMB model typically identified Aroclor 1260, the PCB mixture frequently used in transformers, as the major PCB source confirming the effect of the TMRF on the area. Poor prediction of some sample congener profiles suggest presence of environmental degradation mechanisms such as volatilization and differential solubilization of lower chlorinated congeners from sediments.

Quantitative analysis of healthcare waste generation and composition in Antalya, Turkey.

Health-care waste (HCW) may pose a risk to human health and the environment because of its infectious and/or toxic properties. This study was conducted to evaluate the quantity and composition of all the HCW generated by different producers in Antalya, Turkey, using data obtained from two online systems. Accordingly, this study explored the trends in healthcare waste generation (HCWG) between 2010 and 2020 and the impact of COVID-19 on HCWG by comparing the post- and pre-COVID-19 patterns based on the data obtained from 2,029 different producers. The collected data were based on the waste codes reported by the European Commission, were characterised based on the definition of the World Health Organization, and were further analysed according to the healthcare types defined by the Turkish Ministry of Health to characterize HCW. The findings indicate that the main HCW contributor was infectious waste (94.62 %), most of which was generated by hospitals (80 %). This is due to the inclusion of only HCW fractions in this study and to the definition of infectious waste considered. This study indicates that the categorisation into the type of HCSs may be a good option to assess the increase of HCW quantities, in accordance with the service type, size, and the effects of COVID-19. The correlation results for hospitals offering primary HCS revealed a strong relationship between the HCWG rate and the population per year. This approach may help estimate future trends to promote better HCW management practices for the specific cases considered, and it can even be applied to other cities.

School building energy efficiency and NO2 related risk of childhood asthma in England and Wales: Modelling study.

BACKGROUND: Climate change legislation will require dramatic increases in the energy efficiency of school buildings across the UK by 2050, which has the potential to affect air quality in schools. We assessed how different strategies for improving the energy efficiency of school buildings in England and Wales may affect asthma incidence and associated healthcare utilization costs in the future. METHODS: Indoor concentrations of traffic-related NO2 were modelled inside school buildings representing 13 climate regions in England and Wales using a building physics school stock model. We used a health impact assessment model to quantify the resulting burden of childhood asthma incidence by combining regional health and population data with exposure-response functions from a recent high-quality systematic review/meta-analysis. We compared the effects of four energy efficiency interventions consisting of combinations of retrofit and operational strategies aiming to improve indoor air quality and thermal comfort on asthma incidence and associated hospitalization costs. RESULTS: The highest childhood asthma incidence was found in the Thames Valley region (including London), in particular in older school buildings, while the lowest concentrations and health burdens were in the newest schools in Wales. Interventions consisting of only operational improvements or combinations of retrofit and operational strategies resulted in reductions in childhood asthma incidence (547 and 676 per annum regional average, respectively) and hospital utilization costs (£52,050 and £64,310 per annum regional average, respectively. Interventions that improved energy efficiency without operational measures resulted in higher childhood asthma incidence and hospital costs. CONCLUSION: The effect of school energy efficiency retrofit on NO2 exposure and asthma incidence in schoolchildren depends critically on the use of appropriate building operation strategies. The findings from this study make several contributions to fill the knowledge gap about the impact of retrofitting schools on exposure to air pollutants and their effects on children's health.

Development of a fate and transport model for biodegradation of PBDE congeners in sediments.

Polybrominated diphenyl ethers (PBDEs) are a family where each congener possesses different physicochemical properties, persistence and/or toxicity. Biodegradation can selectively change the abundance of congeners. These warrant modeling of individual congeners by considering biodegradation pathways together with fate and transport (F&T) mechanisms. Accordingly, this study aims to develop a F&T model (Fate and Transport model for Hydrophobic Pollutants - FTHP) that integrates congener specific biodegradation of PBDEs in sediments. The model is tested using sediment data from a location representing the Lower South Bay of San Francisco. Results demonstrated settling, resuspension, and biodegradation as important mechanisms. FTHP is then used to predict congener concentrations in a period of 20 years for two cases (constant and time-dependent water column concentrations) and four alternative scenarios: no intervention (i.e., natural attenuation, also serves as the base case), no degradation, dredging and biostimulation. The greatest impact on the reduction of total PBDE concentrations was achieved by a reduction in water column concentrations, i.e. source control, and dredging. On the other hand, biostimulation coupled with source control was the most effective in reducing bioaccumulative PBDE congener concentrations and almost as effective as dredging for the rest of congeners. Proposed FTHP model can distinguish between congeners and help devise informed management plans which focus on decreasing risks associated with persistent and bioaccumulative compounds in contaminated sediments.

Estimation of rate constants of PCB dechlorination reactions using an anaerobic dehalogenation model.

This study aims to estimate anaerobic dechlorination rate constants (km) of reactions of individual PCB congeners using data from four laboratory microcosms set up using sediment from Baltimore Harbor. Pathway km values are estimated by modifying a previously developed model as Anaerobic Dehalogenation Model (ADM) which can be applied to any halogenated hydrophobic organic (HOC). Improvements such as handling multiple dechlorination activities (DAs) and co-elution of congeners, incorporating constraints, using new goodness of fit evaluation led to an increase in accuracy, speed and flexibility of ADM. DAs published in the literature in terms of chlorine substitutions as well as specific microorganisms and their combinations are used for identification of pathways. The best fit explaining the congener pattern changes was found for pathways of Phylotype DEH10, which has the ability to remove doubly flanked chlorines in meta and para positions, para flanked chlorines in meta position. The range of estimated km values is between 0.0001-0.133d-1, the median of which is found to be comparable to the few available published biologically confirmed rate constants. Compound specific modelling studies such as that performed by ADM can enable monitoring and prediction of concentration changes as well as toxicity during bioremediation.

Positive Matrix Factorization dynamics in fingerprinting: A comparative study of PMF2 and EPA-PMF3 for source apportionment of sediment polychlorinated biphenyls.

Receptor models were typically used in air pollution studies and few publications are available for Positive Matrix Factorization (PMF) that consider the details of parameters and procedures in evaluating the trace organic pollutants in sediments. In this study, environmental fate and source composition of Lake Eymir sediments contaminated by polychlorinated biphenyls (PCBs) were explored by applying two PMF models, Paatero's PMF2 and United States Environmental Protection Agency's (US EPA) EPA-PMF3. PMF2 and EPA-PMF3 rely on different algorithms; Paatero's algorithm and multilinear engine algorithm, respectively. Here, the approaches of two PMF models were compared for the identification of PCB patterns taking into consideration the effects of various uncertainty matrices, residual matrices and goodness-of fit parameters. As a result of the study, it was understood that both models resolved five factors and indicated Clophen A60 as the source of PCBs. These results were consistent with the results resolved by Chemical Mass Balance model applied to the same data set in a previous study. However, source contributions identified by two models differed in quantity, but with similar patterns. This study indicates a way in understanding behavior, fate and global source of persistent organic pollutants in sediment by applying and comparing with a special data including high percentage of below detected value (38.2%) to understand the dynamics of PMF model parameters.