SMC Spain

Most so-called compostable plastics require specific conditions to degrade that are only obtainable in industrial settings, warns a study published in the journal PLoS One. Polylactic acid - a polymer obtained from natural renewable sources that is used as an alternative to petroleum-based plastics - takes more than a year to degrade in a marine environment, compared to 35 days for natural cellulose fibres, according to the analysis, which combines observations in waters off the coast of California (US) with laboratory measurements. 

A study led by researchers from Northeastern University and Stanford University in Boston (USA) has analysed the source of exposure to partisan or unreliable news when searching on Google. After tracking the information consumption of approximately 1,000 people in the 2018 and 2020 US election periods, their conclusions are that such exposure is determined more by users' own active search than by the content displayed by the search engine's algorithm. The results are published in the journal Nature.

Researchers have shown that hypoxia, or oxygen restriction - equivalent to living at 5,000 metres above sea level - increases life expectancy by up to 50% and decreases neurological decline in laboratory mice. It has already been shown in yeast, worms and flies, but this is the first time it has been demonstrated in mammals. The results are published in the journal PLOS Biology. 

A commentary published in the journal Nature Human Behaviour discusses the scientific evidence for why rape victims are often involuntarily paralysed, unable to defend themselves or express themselves without consent, and the implications this has for the world's legal systems.

After three years in which the planet's climate has experienced a phenomenon known as La Niña, in 2023 it gives way to its opposite, El Niño. This has led the World Meteorological Organization to warn that this event, added to climate change, could cause the 1.5 °C limit to be exceeded in the next five years. But what are these "children", how do they affect Spain, how long will they last?

Heat waves and other events accentuated by climate change affect health, especially for the most socially vulnerable people. To counteract these effects, mitigation and adaptation plans for cities are designed based on scientific evidence, the implementation of which belongs to the local political sphere. Two experts in urban health and climate governance analysed these problems and their possible solutions in a briefing organised by SMC Spain.

Fifty-three per cent of the world's largest lakes and reservoirs have lost water between 1992 and 2020, according to a study combining satellite observations, climate data and hydrological models. These results suggest a global trend towards more extensive desiccation than previously thought, in both arid and humid areas, the research team says in the journal Science. The authors also share an online map that includes trends for large freshwater reservoirs in Spain, such as the Iznájar (Córdoba), Mequinenza (Zaragoza) and Valdecañas (Cáceres) reservoirs.

Most high-income countries do not have prostate cancer screening programmes for their entire population; prostate-specific antigen (PSA) tests can be done on an individual basis. In an opinion piece published in The BMJ, a group of urologists and epidemiologists specialised in prostate cancer screening argue for restricting the use of PSA tests to avoid over-detection and over-treatment. 

On 5 April, the UK National IHR Focal Point informed WHO of an increase in severe myocarditis in neonates associated with enterovirus infection in Wales (UK). Between June 2022 and April 2023, ten hospitalised neonates with a positive PCR for enterovirus were found to have myocarditis. Seven of the ten cases were confirmed to have coxsackievirus B3 or coxsackievirus B4. As of 5 May 2023, one patient remained hospitalised and one patient had died. According to the WHO statement, although enterovirus infections are common in neonates and infants, the reported increase in myocarditis - inflammation of heart muscle tissue - with severe outcome associated with enterovirus infection is unusual.

The WHO has issued a new guideline advising against the use of non-sweetened sweeteners for weight control or to reduce the risk of noncommunicable diseases. The recommendation is based on the findings of a systematic review published in 2022.