University of Murcia

In 2021, the eruption of the Tajogaite volcano on the Canary Island of La Palma caused the loss of 53,000 tonnes of bananas, equivalent to 50% of its production, which is essential to the local economy. Given the potential risk of contamination from ash and magma, a team of researchers from Spanish centres analysed the composition of bananas in the area of the eruption. The study, conducted using mass spectrometry and published in PLOS One, confirms that they are safe and healthy to eat. For most potentially toxic elements, the estimated maximum intake remained below 1% of the tolerable daily intake (TDI) and in no case exceeded 3% of the TDI.

A team from Sweden has analysed post mortem brain samples from people aged between 0 and 78 using various techniques and found that, although it varies between individuals, new neurons continue to form in the hippocampus with no apparent age limit. Although previous studies had reached similar conclusions, controversy remains about these results. According to the authors, the new work ‘provides an important piece of the puzzle in understanding how the human brain works and changes throughout life.’ The results are published in the journal Science.

Aging is associated with an increase in chronic inflammation, a phenomenon known as inflammaging that is related to different diseases and that was considered universal. Now, an international team has analyzed data on 19 inflammation-associated proteins in four different populations: two industrialized (from Italy and Singapore) and two non-industrialized (the Tsimane population of the Bolivian Amazon and the Orang Asli population of Malaysia). The results show that, at least according to this form of measurement, in the non-industrialized populations there is no increase in inflammation with age, which questions whether this is a biological imperative and indicates that it would depend on lifestyles and social and cultural factors. The paper is published in letter format in Nature Aging. 

A model has analysed mercury concentrations in rivers around the world from 1850 to the present day. The results, published in Science Advances, conclude that levels have doubled and even tripled since the Industrial Revolution: before 1850, rivers carried approximately 390 metric tonnes of mercury to the oceans each year, and today that figure has risen to around 1,000 metric tonnes. According to the authors, these results have implications for human health and wildlife, as mercury compounds are neurotoxic, can accumulate in fish and pose a health risk through consumption.

Lead exposure in children can affect their neurodevelopment. In the United States, the maximum blood concentration limit for this metal was lowered to 3.5 μg/dL (micrograms per decilitre) in 2021, down from 10 μg/dL in 2012. Now, a study has analysed data from more than 300,000 children in Iowa and found an association between higher concentrations and poorer school performance in reading and maths, even below the 3.5 μg/dL limit, prompting the researchers to reconsider this figure. The results are published in the journal JAMA Network Open.

Up to 1.4 billion people may be living in areas with soil contaminated by heavy metals such as arsenic, cadmium, cobalt, chromium, copper, nickel and lead, according to research published in Science. The paper, which used data from more than 1,000 studies, estimates that 14-17% of farmland worldwide could be contaminated by at least one toxic metal. Cadmium is the most widespread, especially in South and East Asia, parts of the Middle East and Africa.

Toddlers' screen time has a negative correlation with their language skills, according to a study published in PLoS ONE. However, the use of educational content and screen time in the company of adults show a positive association with language skills. The study included nearly 1,900 children between one and four years old from 19 Latin American countries.

Inflammation is all the rage. In fact, anti-inflammatory diets that claim to fight it. This is attested to by best-selling books and influencers, ready to give us the latest tips on how to lose weight, or rather, how to reduce inflammation. But what's the truth in all this, and what does inflammation have to do with being overweight? 

An international team of researchers has analyzed various data sources and scientific literature and identified 3,601 chemical substances in human samples such as blood, urine or breast milk that are known to be in contact with food, for example, because they are used in packaging. According to the authors of the study, “this work shows that food contact materials are not completely safe, even if they comply with regulations, because they transfer known substances to food". The research is published in the Journal of Exposure Science and Environmental Epidemiology.

A study published in Nature in which researchers from the University of Valencia have participated has identified a neuron migration route that begins in the foetus around mid-gestation and continues until between two and three years of age. The route extends from the lateral ventricle, where these cells are born, to the entorhinal cortex, an area related to the regions where memory and learning are consolidated. There, neurons await signals that induce them to mature, providing plasticity to the brain after birth.