Suchergebnisse

ABSTRACTThis paper presents data on the distribution of four herbicides within an agricultural catchment. In the case of mecoprop, 2,4‐dichlorophenoxyacetic acid and simazine, these data include concentrations in the soil, field drains and the stream, before and after applications of the herbicides following good agricultural practice. The concentrations of these herbicides in the soil were found to follow published degradation rates, and their concentrations in the stream and drains were elevated following rainfall with peak concentrations from 0.12 μg/1 to 68.0 μg/1. Atrazine was found at relatively high concentrations (peak 122 μg/1) when it had not been applied to any of the fields draining to the sampling point.The data will be used to test models that may be used as one of a number of tools for the screening of new pesticides prior to their registration. One approach using the Mackay's fugacity model is outlined.

Combinations of intense non-pharmaceutical interventions (lockdowns) were introduced worldwide to reduce SARS-CoV-2 transmission. Many governments have begun to implement exit strategies that relax restrictions while attempting to control the risk of a surge in cases. Mathematical modelling has played a central role in guiding interventions, but the challenge of designing optimal exit strategies in the face of ongoing transmission is unprecedented. Here, we report discussions from the Isaac Newton Institute 'Models for an exit strategy' workshop (11–15 May 2020). A diverse community of modellers who are providing evidence to governments worldwide were asked to identify the main questions that, if answered, would allow for more accurate predictions of the effects of different exit strategies. Based on these questions, we propose a roadmap to facilitate the development of reliable models to guide exit strategies. This roadmap requires a global collaborative effort from the scientific community and policymakers, and has three parts: (i) improve estimation of key epidemiological parameters; (ii) understand sources of heterogeneity in populations; and (iii) focus on requirements for data collection, particularly in low-to-middle-income countries. This will provide important information for planning exit strategies that balance socio-economic benefits with public health.