On any given weekday, the London Underground can see up to five million passengers hopping on and off. Its 11 lines serve 272 stations, and at peak times there can be more than 500 trains hurtling around beneath the streets of London. As it's been in constant use since the 19th Century, the London Underground has remained largely the same, and hasn't been updated or researched as much as other forms of transport.
The pandemic did provide Transport for London (TFL), which manages the London Underground, the opportunity to make some improvements. Ventilation systems were assessed and, according to the Mayor's Transport Strategy Update in 2021, the London Underground ventilation infrastructure is typically designed in excess of statutory minimum requirements with an adequate provision of fresh air. But how fresh is the air you're breathing on the Tube?
The air, even before it gets to the Underground, isn't perfectly clean,” explains Dr David Green, who leads the aerosol science team at Imperial College London and is a member of the UK's Committee on the Medical Effects of Air Pollution (COMEAP). Green is also part of a group commissioned by TfL to regularly assess the COVID-19 risk on the Underground.
The urban background air already has a low level a of particulate matter, but on top of that you have all these extra emissions [coming from the Tube),” he adds.
These include particles that come from the carriage moving along the rails, the brake blocks rubbing on the wheels, and the electrical connection between the collector plate and the live rail. There are also particles that come from Tube passengers, human and otherwise. Hair and skin cells, plastic fibres from clothing, and debris from the creatures that call the Underground their home all contribute to the air quality.
Esta historia es de la edición March 2022 de BBC Science Focus.
Comience su prueba gratuita de Magzter GOLD de 7 días para acceder a miles de historias premium seleccionadas y a más de 9,000 revistas y periódicos.
Ya eres suscriptor ? Conectar
Esta historia es de la edición March 2022 de BBC Science Focus.
Comience su prueba gratuita de Magzter GOLD de 7 días para acceder a miles de historias premium seleccionadas y a más de 9,000 revistas y periódicos.
Ya eres suscriptor? Conectar
COULD MARINE CLOUD BRIGHTENING HELP US FIGHT CLIMATE CHANGE?
The theory behind marine cloud brightening is that brighter or whiter clouds reflect more sunlight back into space.
IS IT SAFE TO RUN EVERY DAY, OR SHOULD I DITCH MY RUN STREAK TO SAVE MY KNEES?
A running streak, where you run every day without taking rest days, can be highly motivating and beneficial for overall fitness. Running is great cardiovascular exercise and isn't to be discouraged (and finding a routine with some consistency is great). Getting a bit of exercise as often as possible is also hugely beneficial for your mental health.
WHAT MAKES THE MEDITERRANEAN DIET SO GOOD FOR US?
The Mediterranean diet may help you live longer, especially if you also adopt the lifestyle of people living near the Med during the 1950s.
WHAT IS MEXICO'S BLUE HOLE?
The world's deepest blue hole (marine sinkhole) lies off the coast of Mexico's Yucatán Peninsula. It's at least 420m (1,378ft) deep, but explorers still haven't found its bottom.
HOW CAN I TELL IF I'VE GOT HIGH CORTISOL LEVELS?
Cortisol is a hormone produced by glands in our bodies called the adrenal glands, which sit above the kidneys. It plays a critical role in various bodily functions, including regulating metabolism, reducing inflammation and helping the body respond to stress. While essential for our health, chronic elevation of cortisol levels can lead to several issues.
THE LUNGFISH
In 1836, European scientists discovered a peculiar animal from the River Amazon that they struggled to identify. Its eel-like body was a few feet long and its air-filled lungs persuaded anatomists it must be a reptile.
ARE WE THE ONLY SPECIES TO HAVE BEEN THROUGH A STONE AGE?
The Stone Age might conjure up images of early humans, sitting around a campfire or hunting prehistoric beasts, but evidence shows that we're not the only species that has learned how to work with stone tools. Wild chimpanzees (Pan troglodytes) use stone tools to crack open nuts.
Should we scrap daylight saving time?
Most of us look forward to the extra hour we get in bed every October, but researchers argue that changing the clocks twice a year harms our health
THE INTERNET OF ANIMALS
SCIENTISTS ARE USING ELECTRONIC TAGS AND SATELLITES TO TRACK WILD ANIMALS AND CREATE A DATA NETWORK THAT COULD HELP US ADDRESS THE BIODIVERSITY CRISIS
MUSIC FOR A DISTRACTED GENERATION
The number of things competing for our attention is often overwhelming. Can dreamy soundscapes created with neuroscience help our bewildered brains to concentrate?
