An assessment of the risks associated with PCDDs and PCDFs following the application of sewage sludge to agricultural land in the UK

A model has been developed to describe the transfer of PCDDs and PCDFs from sludge-amended soils to the human foodchain. The model is conservative and assumes that all foods consumed by an individual are derived from sludge-amended soils. Predicted concentrations of PCDDs and PCDFs in potatoes, cereals, root vegetables and leafy vegetables were in close agreement with mean concentrations reported in the food survey conducted by MAFF in the UK. Predicted concentrations in milk were well below the Maximum Tolerable Concentration adopted by MAFF. Assuming a half-life of ten years in sludge-amended soils, the maximum estimated incremental daily intake (IDI) predicted by the model following ten applications of sludge to agricultural land was 0.80 pg I-TEQ kg⁻¹ day⁻¹, representing an increase of approximately 45% on current levels of background exposure. For an individual whose diet is solely derived from sludge-amended soils, the total exposure is predicted to be approximately 181 pg I-TEQ day⁻¹ or 2.6 pg I-TEQ kg⁻¹ day⁻¹. This compares with an average background exposure of approximately 2 pg I-TEQ kg⁻¹ day⁻¹, well within the TDI of 10 pg I-TEQ kg⁻¹ day⁻¹ and indicates that the application of sewage sludge to agricultural land under the conditions assumed would not appear to present a significant health risk under the conservative scenarios considered in this assessment.     

Model development for household waste prevention behaviour

Understanding waste prevention behaviour (WPB) could enable local governments and decision makers to design more-effective policies for reducing the amount of waste that is generated. By merging well-known attitude–behaviour theories with elements from wider models from environmental psychology, an extensive cognitive framework that provides new and valuable insights is developed for understanding the involvement of individuals in waste prevention. The results confirm the usefulness of the theory of planned behaviour and of Schwartz’s altruistic behaviour model as bases for modelling participation in waste prevention. A more elaborate integrated model of prevention was shown to be necessary for the complete analysis of attitudinal aspects associated with waste prevention. A postal survey of 158 respondents provided empirical support for eight of 12 hypotheses. The proposed structural equation indicates that personal norms and perceived behaviour control are the main predictors and that, unlike the case of recycling, subjective norms have a weak influence on WPB. It also suggests that, since social norms have not presented a direct influence, WPB is likely to be influenced by a concern for the environment and the community as well by perceptions of moral obligation and inconvenience. Results also proved that recycling and waste prevention represent different dimensions of waste management behaviour requiring particular approaches to increase individuals’ engagement in future policies.     

Report: citizen participation as a part of integrated solid waste management: Porto Alegre case.

This study presents the effects of citizen participation on integrated solid waste management. Porto Alegre was chosen as the area of study since its system is a good example for developing countries, based on the partnership between local government and the former scavengers' association that implements selective collection in the city. A life-cycle approach was used to estimate environmental loadings and economic costs based on solid waste generation, and a survey assessment tool was used to analyse social aspects. The results showed a decrease in environmental and economic impacts in the current situation, allowing Porto Alegre to have one of the most affordable integrated solid waste management systems in Brazil. The survey assessment pointed out that public campaign changed the perceptions and practices of most of Porto Alegre's citizens regarding solid waste management. On the other hand, it also pointed out that citizens need more education to increase their participation. Therefore, more research is needed to increase cooperation among all stakeholders, improve citizen participation, and consequently, further decrease the environmental impacts and economic costs.     

Comparison of waste prevention behaviors among three Japanese megacity regions in the context of local measures and socio-demographics

Waste prevention behaviors (WPBs) should be investigated separately from recycling behaviors and analyzed in the context of local policies and measures. Previous studies on WPBs have been mainly conducted in the USA and Europe (mainly in the UK), and studies in Japan have remained very limited to date. Moreover, the effects of socio-demographic factors have been rarely described correctly based on appropriate large sampling. In this study, we conducted an on-line questionnaire survey and obtained 8000 respondents in three megacity regions (Tokyo, Osaka, and Aichi) in Japan. Among these three regions, Osaka respondents showed significantly lower practice rates in nine of 18 WPBs. Particularly in My-bag behavior, the charging of plastic shopping bags strongly affects the practice rate. As shown in the results, local policies and measures affect WPBs. Based on the practice rates, latent four factors were extracted by factor analysis. Multiple regression analysis revealed that gender and age significantly affect WPB factors before local policy effects.