Association of cooking fuel use with risk of cancer and all-cause mortality among Chinese elderly people: a prospective cohort study.

When cooking with biomass and fossil fuels, their incomplete burning can lead to air pollution, which can trigger pernicious effects on people's health, especially among the elderly, who are more vulnerable to toxic and harmful environmental damage. This study explored the association between different cooking fuel types and the risk of cancer and all-cause mortality among seniors constructing Cox regression models. Data were obtained by linking waves of 6, 7, and 8 of the Chinese Longitudinal Healthy Longevity Survey, which included a total of 7269 participants who were 65 years old and over. Cooking fuels were categorized as either biomass, fossil, or clean fuels. And the effects of switching cooking fuels on death risk were also investigated using Cox regression models. The results indicate that, compared with the users of clean fuels, individuals using biomass or fossil fuels were at a greater death risk for cancer [HR (95% CI): biomass, 1.13 (1.05-1.20); fossil, 1.16 (1.06-1.25)] and all causes [HR (95% CI): biomass, 1.29 (1.16-1.42); fossil, 1.32 (1.22-1.50)]. Furthermore, compared with sustained users of biomass fuels, individuals converting from biomass to clean fuels significantly reduced death risk for cancer [HR (95% CI): 0.81 (0.72-0.95)] and all causes [HR (95% CI): 0.76 (0.64-0.93)]. Similarly, all-cause death risk [HR (95% CI): 0.77 (0.62-0.93)] was noticeably reduced among these participants converting from fossil to clean fuels than persistent users of fossil fuels. Subgroup analyses revealed that males had a greater cancer and all-cause death risk when exposed to unclean fuels. These findings can inform the development of policies and the implementation of measures related to cooking fuel use to promote the health of older people and reduce the burden of disease on society.

Biomass use and its health effects among the vulnerable and marginalized refugee families in the Gaza Strip.

Introduction: Biomass fuel remains the most common type of fuel used in many developing countries, leading to indoor air pollution and serious health impacts. Objective: The objective of this study was to compile evidence on the impact household fuel combustion has on child and adult health, with an emphasis on solid fuel use in Gaza. Methods: In this cross-sectional study, 110 structured self-administered questionnaires were distributed in April 2019 among families living in the Al-Maghazi refugee camp. Results: Participants reported that the main fuel used were wood, coal, cardboard, and a mix of wood, cardboard, and plastic, which were used for cooking, heating, baking, boiling water, and lighting. The most common symptoms were nasal irritation (71.8%), followed by headache (66.4%) and dizziness (65.4%). The results of logistic regression showed that the participants who used wood fuel had a higher chance of feeling eye irritation than those who used a mix of wood, cardboard, and dried grass (OR = 1.316; 95% CI = 1.54-8.99). The participants who opened windows during the burning process of biomass fuel were five times more likely to develop pneumonia than those who closed windows (OR = 5.53; 95%CI = 11.60-19.0). Conclusion: there is an urgent need for community awareness campaigns designed to inform people about the risks of exposure to biomass fuel smoke and how to better implement household ventilation.

Molecular mechanism of oil induced growth inhibition in diatoms using Thalassiosira pseudonana as the model species.

The 2010 Deepwater Horizon oil-spill exposed the microbes of Gulf of Mexico to unprecedented amount of oil. Conclusive evidence of the underlying molecular mechanism(s) on the negative effects of oil exposure on certain phytoplankton species such as Thalassiosira pseudonana is still lacking, curtailing our understanding of how oil spills alter community composition. We performed experiments on model diatom T. pseudonana to understand the mechanisms underpinning observed reduced growth and photosynthesis rates during oil exposure. Results show severe impairment to processes upstream of photosynthesis, such as light absorption, with proteins associated with the light harvesting complex damaged while the pigments were unaffected. Proteins associated with photosynthetic electron transport were also damaged, severely affecting photosynthetic apparatus and depriving cells of energy and carbon for growth. Negative growth effects were alleviated when an organic carbon source was provided. Further investigation through proteomics combined with pathway enrichment analysis confirmed the above findings, while highlighting other negatively affected processes such as those associated with ferroxidase complex, high-affinity iron-permease complex, and multiple transmembrane transport. We also show that oxidative stress is not the primary route of negative effects, rather secondary. Overall, this study provides a mechanistic understanding of the cellular damage that occurs during oil exposure to T. pseudonana.

Biomass fuel use and acute respiratory infection among children younger than 5 years in Ethiopia: a systematic review and meta-analysis.

OBJECTIVES: The objective of this study was to estimate the magnitude of acute respiratory infection (ARI) among children younger than 5 years (under-five children) and its association with biomass fuel use for domestic purposes and other behavioural and housing characteristics in Ethiopia. STUDY DESIGN: Systematic review and meta-analysis. METHODS: PubMed, Google Scholar, MEDLINE and the Cochrane Library were systematically searched (using the Preferred Items for Systematic Review and Meta-analysis guideline) for studies that reported an association between biomass fuel use for domestic purposes and ARI. Grey literature and other sources of unpublished information, which were subjected to the same extraction methods and quality appraisal as published studies, were also identified. A meta-analysis was performed to combine the quantitative measures from eligible individual studies into a summary estimate. Quality assessment was conducted using the modified Newcastle-Ottawa Scale quality assessment tool for cross-sectional and case-control studies. Funnel and Doi plots were used to detect potential publication bias. Statistical analyses were performed using Comprehensive Meta-Analysis and MetaXL, version 5.3, software. RESULTS: A total of 21 (18 cross-sectional and 3 case-control) eligible studies with their combined 30,013 participants were reviewed. The overall pooled prevalence of ARI among under-five children in households where biomass fuel was the main source of energy was estimated to be 22% (95% confidence interval [CI]: 17-29). In the subgroup analysis by area of residence, the highest prevalence was found in urban regions 26% (95% CI: 24-28). Based on the preceding 2 weeks before the interview, a significant association was found between biomass fuel use and ARI (odds ratio [OR] = 2.6, 95% CI: 2.05-3.30). In addition to biomass fuel use, being female (OR = 1.57, 95% CI: 1.06-2.33), absence of a window in the kitchen (OR = 2.89, 95% CI: 2.11-3.96), being carried on the back or in lap during cooking (OR = 2.76, 95% CI: 1.96-3.89) and non-separated kitchen from the main house (OR = 1.99, 95% CI: 1.49-2.68) were associated with ARI. CONCLUSIONS: Based on the results of this review, ARI among under-five children remains high. The present study also revealed that ARI is associated with biomass fuel use, child's gender, absence of a window in the kitchen, non-separated kitchen and carrying the child while cooking. Improved solid fuel stoves, advanced combustion designs, windows or chimneys, separating the kitchen from the main house are all measures required to reduce ARI in under-five children. SYSTEMATIC REVIEW REGISTRATION: The review has been registered with PROSPERO (registration number CRD42020181372).

Robust paths to net greenhouse gas mitigation and negative emissions via advanced biofuels.

Biofuel and bioenergy systems are integral to most climate stabilization scenarios for displacement of transport sector fossil fuel use and for producing negative emissions via carbon capture and storage (CCS). However, the net greenhouse gas mitigation benefit of such pathways is controversial due to concerns around ecosystem carbon losses from land use change and foregone sequestration benefits from alternative land uses. Here, we couple bottom-up ecosystem simulation with models of cellulosic biofuel production and CCS in order to track ecosystem and supply chain carbon flows for current and future biofuel systems, with comparison to competing land-based biological mitigation schemes. Analyzing three contrasting US case study sites, we show that on land transitioning out of crops or pasture, switchgrass cultivation for cellulosic ethanol production has per-hectare mitigation potential comparable to reforestation and severalfold greater than grassland restoration. In contrast, harvesting and converting existing secondary forest at those sites incurs large initial carbon debt requiring long payback periods. We also highlight how plausible future improvements in energy crop yields and biorefining technology together with CCS would achieve mitigation potential 4 and 15 times greater than forest and grassland restoration, respectively. Finally, we show that recent estimates of induced land use change are small relative to the opportunities for improving system performance that we quantify here. While climate and other ecosystem service benefits cannot be taken for granted from cellulosic biofuel deployment, our scenarios illustrate how conventional and carbon-negative biofuel systems could make a near-term, robust, and distinctive contribution to the climate challenge.

Household cooking fuel use and its health effects among rural women in southern India-A cross-sectional study.

The use of biomass fuel is associated with the deterioration of human health and women are more likely to develop health conditions due to their exposure to indoor air pollution during cooking. This study was conducted to assess the pattern of fuel used for cooking in households as well as to determine the association between the types of fuel used with respect to socio-demographic characteristics and health status of women. A community based cross-sectional survey was conducted between August 2016 and September 2018 in four rural areas and one semi-urban area of Udupi district, Karnataka, India. The study comprised 587 families including 632 women. A pre-tested semi-structured questionnaire was used to collect data on the type of fuel as well as self-reported health conditions. Overall, 72.5% of the families used biomass, where 67.2% families were currently using both biomass and liquefied petroleum gas while only biomass was used in 5.3% of the families for cooking. Among women, being ever exposed to biomass fuel was significantly associated with their age, literacy level, occupation and socio-economic status (p < 0.001). Those who were exposed to biomass fuel showed a significant association with self-reported ophthalmic (AOR = 3.85; 95% CI: 1.79-8.29), respiratory (OR = 5.04; 95% CI: 2.52-10.07), cardiovascular (OR = 6.07; 95% CI: 1.88-19.67), dermatological symptoms /conditions (AOR = 3.67; 95% CI: 1.07-12.55) and history of adverse obstetric outcomes (AOR = 2.45; 95% CI: 1.08-5.57). A positive trend was observed between cumulative exposure to biomass in hour-years and various self-reported health symptoms/conditions (p < 0.001). It was observed that more than two-thirds of women using biomass fuel for cooking were positively associated with self-reported health symptoms. Further longitudinal studies are essential to determine the level of harmful air pollutants in household environment and its association with various health conditions among women in this region.

Expression of Metazoan Annexins in Yeast Provides Protection Against Deleterious Effects of the Biofuel Isobutanol.

The ability of microorganisms to produce biofuels by fermentation is adversely affected by the perturbing effects of the hydrophobic biofuel on plasma membrane structure. It is demonstrated here that heterologous expression of metazoan, calcium-dependent, membrane-binding proteins of the annexin class can reduce deleterious effects of isobutanol on Saccharomyces cerevisiae viability and complex membrane functions. Therefore, expression of annexins in industrial strains of yeast or bacteria may prove beneficial in biofuel production.

Ethanol and Methanol Burn Risks in the Home Environment.

Biofuel heaters and fireplaces have in recent years been introduced for indoor and outdoor use. Due to their simplicity, they are usually equipped with few or no safety features. Worldwide, incidents resulting in major skin burn injury and long hospitalization periods have occurred when using such biofuel units. The present study analyses the characteristics of the liquids ethanol and methanol to get a scientific background for understanding related accidents. The comparably heavy vapors, especially from ethanol, may generate a pillow of combustible gas in the vicinity of the unit, particularly in quiescent indoor air conditions. It is also revealed that these fuels represent a potential severe risk, since the equilibrium vapor pressures are close to the stoichiometric fuel⁻air composition at normal room temperatures. Selected incidents were reviewed to understand the mechanisms involved when severe burns were received by the users. It turns out that the most severe incidents were related to refilling operations and included ignition of the fuel container vapor phase. When ignited, the container gas phase expansion propelled burning fuel from the bottle or container onto the user or other persons in the vicinity. Similar incidents involving refilling methanol for chemistry demonstrations and ethanol for endodontic (dentistry) treatment were also studied and it was shown that these accidents followed similar accident mechanisms. It may be concluded that the main contributors to burn risk are the near-stoichiometric vapor pressure of these liquids at room temperature and the close proximity of the fuel container to burning fuel. Research needs and possible technical barriers are suggested to reduce this risk for the future.

Biocides Used as Additives to Biodiesels and Their Risks to the Environment and Public Health: A Review.

One of the advantages of using biodiesel and its blends with diesel oil is the lower levels of emissions of particulate matter, sulfur dioxide, carbon monoxide, among others, making it less harmful to the environment and to humans. However, this biofuel is susceptible to microbial contamination and biodeterioration. In this sense, studies on the use of effective low toxicity biocides are being carried out, and this work aims to present the latest information (2008⁻2018) available in the scientific databases, on the use of biocides in biodiesel, mainly concerning their toxicity to the environment and public health. The results showed that in relation to the control of microbial contamination, the current scenario is limited, with seven publications, in which the most studied additives were isothiazolinones, oxazolidines, thiocyanates, morpholines, oxaborinanes, thiocarbamates and phenolic antioxidants. Studies regarding direct experiments with humans have not been found, showing the need for more studies in this area, since the potential growth of biodiesel production and consumption in the world is evident. Thus, there are need for more studies on antimicrobial products for use in biodiesel, with good broad-spectrum activity (bactericidal and fungicidal), and further toxicological tests to ensure no or little impact on the environment.

Effects of Adding Chicken Blood Meal and Fishmeal to Sludge Biogas as White Oyster Mushroom Media.

BACKGROUND AND OBJECTIVE: The biogas sludge is generally not used optimally and people even pour it directly into the river that it cause environmental pollution. One of the ways to get the benefit from sludge and chicken blood meal or fishmeal is to use it as a substitute for bran in mushroom media. This study aimed to improve the nutrient content of biogas sludge with the addition of chicken blood meal (CBM) and fishmeal (FM) as substitute material for bran in white oyster mushroom media. MATERIALS AND METHODS: The biogas sludge was dried in the sun for 3 days until its form resembled the soil. The treatment consisted of dried biogas sludge without CBM (BP0), dried biogas sludge with 1% CBM (BP1) and dried biogas sludge with 3% CBM (BP2). Each was added to the media of white oyster mushroom as much as 15% as substitute material for bran. The other treatment consisted of dried biogas sludge without FM (FP0), dried biogas sludge with 2% FM (FP1) and dried biogas sludge with 4% FM (FP2). Each was added to the media of white oyster mushroom as much as 5% as substitute material for bran. BP0 and FP0 created from white oyster mushroom media were commonly used by farmers. Each treatment was analyzed of nutritional and biological contents. All the data were tested using completely randomized design one-way ANOVA. RESULTS: The results of the research on the use of chicken blood meal and fishmeal showed that the best treatments were BP2 and FP2. Their nutrient content increased, including the organic-C, organic matter, nitrogen, P2O5 and K2O. The productivity of the oyster mushroom increased, shown by the increase of fresh weight and diameter of caps in treatment BP2. The replacement of bran by biogas sludge with 4% FM addition (FP2) in oyster mushroom media increased the fresh weight, the number of caps and the length of oyster mushroom stalks. CONCLUSION: The best treatments for mushroom media were BP2 and FP2 to be used as substitute material for bran in white oyster mushroom media.

Community Participatory Interventions to Improve Farmer Knowledge and Practices of Household Biogas Unit Operation in Ha Nam Province, Vietnam.

CONTEXT: The use of biogas systems to treat livestock waste is a common practice in Vietnam. However, farmers' knowledge and practices of the safe and appropriate use of household biogas units (HBUs) are still limited and could negatively impact human, animal, and environmental health. OBJECTIVE: To assess the effectiveness of an intervention to improve knowledge and practices of biogas operation among farmers in 2 communes of Ha Nam Province, Vietnam. DESIGN: A community-based intervention approach. SETTING: This study was conducted from 2015 to 2016 in 2 communes of Ha Nam Province, Vietnam. PARTICIPANTS: Only farmers with HBUs (N = 399) participated in this research. Farmers were assigned to either an intervention group or a control group at a ratio of 1:2. INTERVENTION: Two intervention steps were implemented over a 6-month period as follows: (i) the core farmer group trained in 6 steps of HBU safe handling practice; and (ii) the core farmer group conducted peer-to-peer communication with its neighbors in the commune using the provided material. MAIN OUTCOME MEASURE(S): Farmers' knowledge and practices in biogas operation were assessed by a structured questionnaire. The questionnaire was administered before (baseline) and after the intervention (follow-up) to both the control and intervention groups. RESULTS: There was a significant difference in the knowledge and practices of biogas operation between the 2 groups, in which farmers in the intervention group demonstrated better understanding of the related topic than the control group (P < .05, t test). A linear regression model indicated that baseline and follow-up scores in both knowledge and practices of the intervention group were higher than those of the control group. After the intervention, the mean difference score in knowledge and practices between the intervention and control groups was 5.0 and 2.0 points, respectively (P < .01). CONCLUSION: A community-based intervention approach could be applied to improve knowledge and practices among farmers in using biogas systems. However, further studies should be conducted to assess the sustainability and effectiveness of this model.

Impact of cleaner fuel use and improved stoves on acute respiratory infections: evidence from India.

Background: The use of cleaner fuel and improved stoves has been promoted as a means to lower harmful emissions from solid fuels. However, little is known about how exclusive use of cleaner fuels, mixed fuel use and improved stoves influences children's health. Methods: We compared the impact of using liquefied petroleum gas (LPG) exclusively with mixed fuel use (LPG plus polluting fuels) and with exclusive use of polluting fuels on acute respiratory infections (ARI) among 16 157 children 0-4 years of age from households in the 2012 Indian Human Development Survey. Inverse probability weighting (IPW) procedures for multiple treatments were used for this evaluation. Results: Children from households using LPG had a 5.0% lower probability of reporting ARI relative to exclusive users of polluting fuels, with larger effects (10.7%) in rural households. The probability of ARI in households using improved stoves and mixed fuel use was also lower in rural households, by 2.9% and 2.8%, respectively. The magnitude of effect varied across population subgroups, with the highest effects for children living in households living in kachha (low quality material) houses households identified as poor. Conclusion: Use of LPG and improved stoves lowered the probability of ARI among children younger than 5 years.

Histopathological and Reproductive Evaluation in Male Rats Fed Jatropha curcas Seed Cake with or without Alkaline Hydrolysis and Subjected to Heat Treatment.

Jatropha curcas cake, a by-product of biodiesel production, is rich in protein and has potential to be used in livestock feed; however, the presence of antinutritional factors and phorbol esters limits its use. Thus, this study investigated toxicological and reproductive effects in male Wistar rats after subchronic exposure to J. curcas cake subjected to detoxification procedures. Rats were divided into seven groups (n = 10) and treated for 60 days. The control group received commercial feed, while experimental groups received a diet containing 5% J. curcas cake nonhydrolyzed or hydrolyzed with 5 M NaOH. The cakes were unwashed or washed with ethanol or water and were autoclaved at 121°C for 30 minutes. Alkaline hydrolysis combined with ethanol washing decreased the phorbol ester concentration in the cake by 98%. Histopathological findings included diffuse degeneration of the liver and edema around the pulmonary vessels in the nonhydrolyzed groups. In addition, nontreated females mated with males of nonhydrolyzed unwashed group showed a decreased number of live fetuses and an increased placental weight. There were no signs of toxicity in rats given hydrolyzed cakes washed and unwashed, indicating that alkaline hydrolysis associated with heat treatment is an efficient method for detoxification of the J. curcas cake.

[Preliminary analysis of lung function of population with biofuel smoke exposure].

Objective: To analyse the impaired lung functions of people with biofuel smoke exposure. Methods: Nonsmokers with biofuel smoke exposure were selected as research objects in a mountainous area of northern Guangdong where the families used biofuels as main energies and the nonsmokers without biofuel smoke exposure in the same area as control. Questionnaire interviews and spirometry tests were performed on all subjects. To analyse the differences of lung functions in both. Results: Seventy hundred and seventeen subjects were enro1led in this study.There were 530 nonsmokers with biofuel smoke exposure(observation group) including 442 women and 88 men, average age 54±10. There were 187 nonsmokers without biofuel smoke exposure(control group) including 141 women and 46 men, average age 54±10. There was no significant difference between two groups in age, height, weight, BMI, waist circumference, hip circumference and waist/hip ratio(P>0.05). The pulmonary ventilation function index(FEV(1)%Pred, FEV(1)/FVC) in the observation group was significantly less than that in control group [(100±18) vs.(106±25); (80±10) vs.(83±6) respectively, P<0.05]. Small airway function index(PEF25, PEF50, PEF75, MMPEF and MMPEF%Pred) was significantly less than that in control group(P<0.01). According to the univariate regression analysis and multivariate regression analysis, regression coefficients between BIOFUEL-INDEX and FEV/FVC was -0.1, 95%CI(-0.1, -0.1, P<0.01). According to the threshold analysis, the vertice of BIOFUEL-INDEX was 46.0, where the predicted Y value was 81.76, 95%CI (80.2, 83.33). When BIOFUEL-INDEX<46.0, the regression coefficient was 0, 95%CI (-0.1, 0.0)(P>0.05); when BIOFUEL-INDEX> 46.0, the regression coefficient 2 was -0.1, 95%CI (-0.2, -0.1)(P<0.01). The difference between coefficient 2 and 1 was -0.1, 95%CI (-0.2, 0.0), which was statistically significant (P<0.05). The Log-Likelihood ratio between Model I and Model Ⅱ had statistical significance (P=0.019). Conclusions: The biofuel smokes exposure causes damages in lung function.

Health impacts of anthropogenic biomass burning in the developed world.

Climate change policies have stimulated a shift towards renewable energy sources such as biomass. The economic crisis of 2008 has also increased the practice of household biomass burning as it is often cheaper than using oil, gas or electricity for heating. As a result, household biomass combustion is becoming an important source of air pollutants in the European Union.This position paper discusses the contribution of biomass combustion to pollution levels in Europe, and the emerging evidence on the adverse health effects of biomass combustion products.Epidemiological studies in the developed world have documented associations between indoor and outdoor exposure to biomass combustion products and a range of adverse health effects. A conservative estimate of the current contribution of biomass smoke to premature mortality in Europe amounts to at least 40 000 deaths per year.We conclude that emissions from current biomass combustion products negatively affect respiratory and, possibly, cardiovascular health in Europe. Biomass combustion emissions, in contrast to emissions from most other sources of air pollution, are increasing. More needs to be done to further document the health effects of biomass combustion in Europe, and to reduce emissions of harmful biomass combustion products to protect public health.

Design Criteria for Future Fuels and Related Power Systems Addressing the Impacts of Non-CO2 Pollutants on Human Health and Climate Change.

Concerns over the economics, supply chain, and emissions of greenhouse gases associated with the wide use of fossil fuels have led to increasing interest in developing alternative and renewable fuels for stationary power generation and transportation systems. Although there is considerable uncertainty regarding the economic and environmental impacts of alternative and renewable fuels, there is a great need for assessment of potential and emerging fuels to guide research priorities and infrastructure investment. Likewise, there is a great need to identify potential unintended adverse impacts of new fuels and related power systems before they are widely adopted. Historically, the environmental impacts of emerging fuels and power systems have largely focused on carbon dioxide emissions, often called the carbon footprint, which is used to assess impacts on climate change. Such assessments largely ignore the large impacts of emissions of other air pollutants. Given the potential changes in emissions of air pollutants associated with the large-scale use of new and emerging fuels and power systems, there is a great need to better guide efforts to develop new fuels and power systems that can avoid unexpected adverse impacts on the environment and human health. This review covers the nature of emissions, including the key components and impacts from the use of fuels, and the design criteria for future fuels and associated power systems to assure that the non-CO2 adverse impacts of stationary power generation and transportation are minimized.

Biodiesel exhaust: the need for a systematic approach to health effects research.

Biodiesel is a generic term for fuel that can be made from virtually any plant or animal oil via transesterification of triglycerides with an alcohol (and usually a catalyst). Biodiesel has received considerable scientific attention in recent years, as it is a renewable resource that is directly able to replace mineral diesel in many engines. Additionally, some countries have mandated a minimum biodiesel content in all diesel fuel sold on environmental grounds. When combusted, biodiesel produces exhaust emissions containing particulate matter, adsorbed chemicals and a range of gases. In many cases, absolute amounts of these pollutants are lower in biodiesel exhaust compared with mineral diesel exhaust, leading to speculation that biodiesel exhaust may be less harmful to health. Additionally, engine performance studies show that the concentrations of these pollutants vary significantly depending on the renewable oil used to make the biodiesel and the ratio of biodiesel to mineral diesel in the fuel mix. Given the strategic and legislative push towards the use of biodiesel in many countries, a concerning possibility is that certain biodiesels may produce exhaust emissions that are more harmful to health than others. This variation suggests that a comprehensive, systematic and comparative approach to assessing the potential for a range of different biodiesel exhausts to affect health is urgently required. Such an assessment could inform biodiesel production priorities, drive research and development into new exhaust treatment technologies, and ultimately minimize the health impacts of biodiesel exhaust exposure.

Ecotoxicological assessment of residues from different biogas production plants used as fertilizer for soil.

Residues from biogas production (RBP) are a relatively new materials, which may be an interesting resource for the improvement of soil fertility. Nevertheless, in spite of the potential benefits from the agricultural utilization of RBP, there is a need of comprehensive estimation of their toxicity. This information is needed to exclude potential negative environmental impacts arising from the use of RBP. Samples of RBP obtained from six biogas production plants with varied biogas production methods were analysed. The samples with and without separation on solid and liquid phases were investigated. The physicochemical properties of the RBP, heavy metals content (Cr, Cu, Ni, Cd, Pb i Zn) and toxicity on bacteria (Vibrio fischeri, MARA test - 11 different strains), collembolans (Folsomia candida) and two plant species (Lepidium sativum and Sinapis alba) was investigated. Toxicity of RBP was examined using Phytotoxkit F (root growth inhibition), collembolan test (mortality, inhibition of reproduction), Microtox® (inhibition of the luminescence of V. fischeri) and MARA test (growth of microorganisms). An especially negative effect on the tested organisms whereas was noted for the liquid phase after separation. In many cases, RBP without separation also showed unfavourable effects on the tested organisms. Liquid phase after separation and non-separated materials caused inhibition of root growth of L. sativum and S. alba at the level of 17.42-100% and 30.5-100%, respectively, as well as the inhibition of reproduction of F. candida with the range from 68.89 to 100%. In most cases, no ecotoxicological effect was observed for solid phase after separation for tested organisms. The solid phase after separation presented the most favorable properties between all investigated RBP. Therefore, it can be a potential material for the improvement of soil properties and for later use in agriculture.

Caregiver perception of sleep-disordered breathing-associated symptoms in children of rural Andean communities above 4000 masl with chronic exposure to biomass fuel.

BACKGROUND: Previous studies have uncovered a very high prevalence of sleep disorders in general, and of sleep-disordered breathing in particular among children exposed to indoor biomass fuel pollution. However, despite the significant symptomatology, parents are unlikely to report these issues during health-care visits. OBJECTIVE: The objective of this study was to determine whether reduced caregiver perception of sleep disorders may account for the infrequent diagnosis and treatment of such problems in children residing at high altitudes and exposed to high biomass pollution. METHODS: Parents of children aged 9-15 years of three communities residing in the Pasco region in Peru located between 3800 and 4200 meters above sea level were surveyed using a validated questionnaire instrument focused on symptoms associated with sleep-disordered breathing as well as whether caregivers perceived that their child suffered from a sleep disorder. RESULTS: Among the 77 children included, 48.1% had nocturnal awakenings and 46.8% had repetitive movements and restless sleep. Habitual snoring was present in 33.8% of all children. However, only 10.4% of mothers considered that their children had sleep problems, and all of their children had positive answers for ≥4 sleep symptoms. CONCLUSIONS: Children residing at high altitudes and exposed to traditional biomass-fueled stoves exhibit an extremely high frequency of sleep symptoms that are misperceived by their mothers as being "normal." Interventions aimed at increasing parental recognition and awareness of sleep problems will be essential to foster improved diagnosis and treatment.

Application of theory-based evaluation for the critical analysis of national biofuel policy: A case study in Malaysia.

Theory-based evaluation (TBE) is an effectiveness assessment technique that critically analyses the theory underlying an intervention. Whilst its use has been widely reported in the area of social programmes, it is less applied in the field of energy and climate change policy evaluations. This paper reports a recent study that has evaluated the effectiveness of the national biofuel policy (NBP) for the transport sector in Malaysia by adapting a TBE approach. Three evaluation criteria were derived from the official goals of the NBP, those are (i) improve sustainability and environmental friendliness, (ii) reduce fossil fuel dependency, and (iii) enhance stakeholders' welfare. The policy theory underlying the NBP has been reconstructed through critical examination of the policy and regulatory documents followed by a rigorous appraisal of the causal link within the policy theory through the application of scientific knowledge. This study has identified several weaknesses in the policy framework that may engender the policy to be ineffective. Experiences with the use of a TBE approach for policy evaluations are also shared in this report.