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The microcystin biodegradation potential of a natural bacterial community coexisting with a toxic cyanobacterial bloom was investigated in a water reservoir from central Spain. The biodegradation capacity was confirmed in all samples during the bloom and an increase of mlrA gene copies was found with increasing microcystin concentrations. Among the 24 microcystin degrading strains isolated from the bacterial community, only 28% showed presence of mlrA gene, strongly supporting the existence and abundance of alternative microcystin degradation pathways in nature. In vitro degradation assays with both mlr+ and mlr− bacterial genotypes (with presence and absence of the complete mlr gene cluster, respectively) were performed with four isolated strains (Sphingopyxis sp. IM-1, IM-2 and IM-3; Paucibacter toxinivorans IM-4) and two bacterial degraders from the culture collection (Sphingosinicella microcystinivorans Y2; Paucibacter toxinivorans 2C20). Differences in microcystin degradation efficiencies between genotypes were found under different total organic carbon and total nitrogen concentrations. While mlr+ strains significantly improved microcystin degradation rates when exposed to other carbon and nitrogen sources, mlr− strains showed lower degradation efficiencies. This suggests that the presence of alternative carbon and nitrogen sources possibly competes with microcystins and impairs putative non-mlr microcystin degradation pathways. Considering the abundance of the mlr− bacterial population and the increasing frequency of eutrophic conditions in aquatic systems, further research on the diversity of this population and the characterization and conditions affecting non-mlr degradation pathways deserves special attention.

Lignocellulosic biomass pyrolysis could be an economically feasible option for forest management as it reduces the need to burn litter and helps in fire prevention thus avoiding the release of carbon dioxide and other greenhouse gases into the atmosphere. This study characterises wood vinegar (WV) obtained via a continuous fast pyrolysis process in terms of its composition, ageing and herbicidal properties. The aqueous WV fraction had a moisture content of 84% in weight and contained more than 200 compounds. Acetic acid, hydroxyacetaldehyde and hydroxyacetone were the major components. No significant differences were found in WV composition according to the starting material (poplar, pine, pruning litter, forest waste). No residual aromatic polycyclic compounds that could be harmful to the environment were detected. In a series of climate-controlled glass chamber experiments, the WV proved to be as effective an inhibitor of seed germination and seedling growth as a contact herbicide acting against weeds, especially through aerial contact. Sprayed WV concentrations of 50, 75 and 100 vol. % were effective against all plant species tested. This product could therefore be of commercial interest and help make biomass pyrolysis economically viable, once environmental exposure limits and the safe application for agricultural and urban use of this product have been established.

The presence of SARS-CoV-2 RNA in wastewater was first reported in March 2020. Over the subsequent months, the potential for wastewater surveillance to contribute to COVID-19 mitigation programmes has been the focus of intense national and international research activities, gaining the attention of policy makers and the public. As a new application of an established methodology, focused collaboration between public health practitioners and wastewater researchers is essential to developing a common understanding on how, when and where the outputs of this non-invasive community-level approach can deliver actionable outcomes for public health authorities. Within this context, the NORMAN SCORE “SARS-CoV-2 in sewage” database provides a platform for rapid, open access data sharing, validated by the uploading of 276 data sets from nine countries to-date. Through offering direct access to underpinning meta-data sets (and describing its use in data interpretation), the NORMAN SCORE database is a resource for the development of recommendations on minimum data requirements for wastewater pathogen surveillance. It is also a tool to engage public health practitioners in discussions on use of the approach, providing an opportunity to build mutual understanding of the demand and supply for data and facilitate the translation of this promising research application into public health practice.