To spread or not to spread? Assessing the suitability of sewage sludge and other biogenic wastes for agriculture reuse.

Sewage sludge (biosolids) management represents a worldwide issue. Due to its valuable properties, approximately one half of the EU production is recovered in agriculture. Nevertheless, growing attention is given to potential negative effects deriving from the presence of harmful pollutants. It is recognized that a (even very detailed) chemical characterization is not able to predict ecotoxicity of a mixture. However, this can be directly measured by bioassays. Actually, the choice of the most suitable tests is still under debate. This paper presents a multilevel characterization protocol of sewage sludge and other organic residues, based on bioassays and chemical-physical-microbiological analyses. The detailed description of the experimental procedure includes all the involved steps: the criteria for selecting the organic matrices to be tested and compared; the sample pre-treatment required before the analyses execution; the chemical, physical and microbiological characterisation; the bioassays, grouped in three classes (baseline toxicity; specific mode of action; reactive mode of action); data processing. The novelty of this paper lies in the integrated use of advanced tools, and is based on three pillars:•the direct ecosafety assessment of the matrices to be reused.•the adoption of innovative bioassays and analytical procedures.•the original criteria for data normalization and processing.

Conceptualizing and measuring migration policy change.

This paper outlines the methodology of DEMIG POLICY, a new database tracking around 6,000 migration policy changes in 45 countries between 1945 and 2014. The article conceptualizes the notion of migration policy change and presents the coding system used to operationalize policy content, changes in policy restrictiveness, as well as the magnitude of policy changes. The paper also discusses the potential of DEMIG POLICY to improve our understanding of the nature, evolution, and effectiveness of migration policies. Besides significantly extending the geographical and historical coverage of existing migration policy databases, DEMIG POLICY also tracks emigration policies in order to overcome the common 'receiving country bias' in migration research. By offering key insights into the main features of the largest migration policy database completed to date, this paper hopes to provide useful guidelines to improve future efforts to measure migration policies. Such improvement is crucial given the heated debates on migration policy effectiveness on one hand and the still limited empirical evidence on this issue on the other.