Gamma radiation induces hydrogen absorption by copper in water

One of the most intricate issues of nuclear power is the long-term safety of repositories for radioactive waste. These repositories can have an impact on future generations for a period of time orders of magnitude longer than any known civilization. Several countries have considered copper as an outer corrosion barrier for canisters containing spent nuclear fuel. Among the many processes that must be considered in the safety assessments, radiation induced processes constitute a key-component. Here we show that copper metal immersed in water uptakes considerable amounts of hydrogen when exposed to γ-radiation. Additionally we show that the amount of hydrogen absorbed by copper depends on the total dose of radiation. At a dose of 69 kGy the uptake of hydrogen by metallic copper is 7 orders of magnitude higher than when the absorption is driven by H2(g) at a pressure of 1 atm in a non-irradiated dry system. Moreover, irradiation of copper in water causes corrosion of the metal and the formation of a variety of surface cavities, nanoparticle deposits, and islands of needle-shaped crystals. Hence, radiation enhanced uptake of hydrogen by spent nuclear fuel encapsulating materials should be taken into account in the safety assessments of nuclear waste repositories.Peer reviewe

Parental recommendations for population level interventions to support infant and family dietary choices: a qualitative study from the Growing Up in Wales, Environments for Healthy Living (EHL) study

Background: Childhood obesity presents a challenge to public health. This qualitative study explored the main barriers to dietary choices faced by parents with infants, and the types of interventions and policy level recommendations they would like to see put in place, to promote a healthier food environment. Methods: 61 semi-structured interviews with prospective parents and parents of infants (61 mothers and 35 fathers) were conducted. Families were selected according to community deprivation levels using the Townsend Deprivation Index to ensure a representative sample from deprived and affluent neighbourhoods. Inductive thematic analysis was used to analyse the data. Results: Parents identified triggers which led to unhealthy dietary choices such as reliance on fast food outlets due to; shift work, lack of access to personal transport, inability to cook, their own childhood dietary experiences, peer pressure and familial relationships. Parents who made healthy dietary choices reported learning cooking skills while at university, attending community cooking classes, having access to quality food provided by church and community organisations or access to Healthy Start vouchers. They called for a reduction in supermarket promotion of unhealthy food and improved access to affordable and high-quality fresh produce in the local area and in supermarkets. There was a strong message to policy makers to work with commercial companies (food manufactures) as they have resources to lower costs and target messages at a diverse population. Provision of targeted advice to fathers, minority ethnic parents, and tailored and practical advice and information on how to purchase, prepare, store and cook food was requested, along with community cookery classes and improved school cookery lessons. Conclusions: There is a need for parent directed community/population level interventions that aims to reduce socio-ecological barriers to making healthy dietary choices. Parents desired improvements in meals provided in workplaces, schools and hospitals, as well as increased access to healthy foods by increasing local healthy food outlets and reducing unhealthy, fast food outlets. Knowledge and skills could then be enhanced in line with these improvements, with confidence gained around cooking and storing food appropriately.14 page(s