You remember acid rain, right?
Acid rain, like holes in the ozone layer, was a phrase that almost everyone knew from the 1970s to the 2000s.
People had images of taking out their umbrellas only to see the fabric melt away and their clothes not long after – not something you want to sing in.
While it wasn’t quite that, acid rain makes wetlands more acidic, which is lethal to some fish; leaches nutrients from the soil, killing plants and gnaws at stone buildings and sculptures.
Humanity got a rare environmental win when, after decades of work (and convincing) by scientists, European and North American officials acted to curb emissions and mostly put a stop to acid rain.
But acid rain is back (kind of), an expert told Metro, after a chemical has shown up in lakes, rivers, bottled water, beer and even human urine.
What is acid rain?
The precipitation is caused by fossil-fuel-burning power plants and vehicles pumping out sulphur dioxide and oxides of nitrogen.
The pollution mingles with water vapour up in the clouds to create toxic, corrosive acid.
Acid rain can happen far away from sources of emissions as the wind blows away the gases – acid rain in Japan has been traced back to China.
There’s a new acid in our rain
Scientists have observed over the last few decades that, whenever it rains, the human-made chemical trifluoroacetic acid (TFA) falls with it.
TFA has been found in Canadian ice, Danish groundwater, British rivers and even Austrian cereal, with Germany seeing a fivefold increase in TFA levels in rain since the 1990s.
TFA is used to make blowing agents, like the foam and plastic in packaging materials, as well as pesticides and pharmaceuticals.
But environmental experts like Rowan Stanforth know it as a ‘forever chemical’, or a PFAS, because it takes hundreds of years to break down.
‘Scientists now believe that TFA is the most abundant PFAS pollutant in the world thanks to widespread use and environmental pollution of PFAS,’ Stanforth, a project officer at the antipollution charity, Fidra, told Metro.
TFA is a tiny, wily and agile chemical, easily able to enter waterways and swim around them after being coughed out from industrial discharges.
In June, Firda worked with researchers from the University of York to analyse 32 UK rivers for TFA – just one was not contaminated.
The chemical sneaks into rain through the gases used in air-conditioner units, refrigerators and insulation foam, said Stanforth.
‘The prevalence of TFA in rainfall is a worrying illustration of how far this PFAS can spread and the global problem we are facing,’ Stanforth added.
Is it anything to worry about?
So, there’s a lot of TFA around us right now, apparently. Should we be worried?
Like with other PFAS, how much of a risk, if any, TFA is unclear. Scientists have been debating for decades about how harmful the tiny molecule is, with some saying it’s about as ‘toxic as table salt’.
While German scientists say that TFA is toxic for reproduction and harmful to the environment, calling on EU officials to label it a toxin.
European scientists wrote in a paper last year that what worries them isn’t so much what we do know, it’s what we don’t know, especially as TFA concentrations continue to rise.
The increase could pose a threat to ‘planetary boundaries’, natural processes that must be kept in balance to keep Earth habitable, causing ‘potential irreversible disruptive impacts’.
‘The troubling reality is that we are still learning about the possible effects of TFA on people and wildlife – after we’re already being exposed to it daily,’ said Stanforth.
‘The current levels of TFA pollution in the environment are unprecedented for any PFAS.
‘We do not know the impact of long-term and consistent exposure to these chemicals on human or environmental health, but we do know that these chemicals are persistent and rapidly building in our environment.’
There aren’t any rules or regulations in place to identify and reduce the concentrations of TFA in the environment or water supplies in the UK.
The Drinking Water Inspectorate, which monitors drinking water quality, has commissioned research into the TFA in our taps. Environmental and health and safety officials are involved in the programme.
But Stanforth added that there’s no easy way to remove TFA from the environment – you can’t just run the water through a sieve.
‘We must stop the introduction of these harmful chemicals at the source,’ he said.
‘Every day of delay locks in decades of pollution and environmental harm.’
The Department for Environment, Food and Rural Affairs said in a statement to Metro: ‘Drinking water must not contain any substance at a level which would constitute a potential danger to human health. If Trifluoroacetic acid were detected in drinking water, companies should take action in the same way as for other PFAS compounds.
‘We continue to work closely across government and with regulators and the devolved administrations to assess levels of so-called forever chemicals occurring in the environment, their sources, and potential risks.’
Get in touch with our news team by emailing us at webnews@metro.co.uk.
For more stories like this, check our news page.
MORE: Map shows where thunderstorms and heavy rain will hit UK
MORE: This country will be underwater by 2050 — and people are entering a bleak competition to escape
MORE: What happens to your body in a heatwave after Tampa hits record-breaking 100 degrees?