But they leach into the soil once a building gets knocked down and goes into landfill. Some PFAS used in building materials include big molecules, such as fluoropolymers, used as coatings on roofing, that are not released when it rains. “Mapping the universe of PFAS, and trying to understand which are bad and which aren’t, is an important activity but that is going to take decades and by then it could be too late to do anything about it,” says Cousins. However, not all PFAS are toxic to humans: the chemistry is much more nuanced. PFOA and PFOS were most detrimental at the manufacturing stage, where factory workers were exposed. Two of the most widespread and hazardous – PFOA (perfluorooctanoic acid), used to make Teflon, and PFOS (perfluorooctane sulphonic acid) – have been phased out in most of the world but remain in the oceans. The market for just building materials containing PFAS, however, is worth $26bn (£19bn), according to the American Chemistry Council (compared with $753bn for the semiconductor industry). ‘Forever chemicals’ have been found on Mount Everest. The upstream solution is to not use these persistent chemicals in the first place.” Some transform into more harmful PFAS before coming back into air from the oceans, then raining down back on to land. “We shouldn’t be releasing these man-made substances into the environment because they’re cycling around in water systems. “PFAS are raining down everywhere – you’ll find them in rainwater wherever you live at higher concentrations than the environmental standards set for rivers.”Ĭousins thinks this is a bigger problem than we have acknowledged. “Wherever there is society, there’s use of PFAS,” says Prof Ian Cousins, an environmental chemist at Stockholm University, who has studied this huge, diverse group of chemicals for 20 years. But they are most prevalent where there are lots of people – in European cities’ river catchments, for example. Globally, PFAS have been widely documented in rivers, lakes, wetlands and every ocean they are on Mount Everest and in Arctic sea ice. Mapping the universe of PFAS, and trying to understand which are bad and which aren’t, is going to take decades Prof Ian Cousins
Most of the chemicals from that silky smooth painted wall or rust-free railing ultimately end up in the ocean. Water-treatment plants can use activated carbon to filter out some, but not all, PFAS and other contaminants, but it is expensive and requires high-temperature incineration. Once there, remediation – removing the pollution – is impossible. Exposure to some PFAS has been linked to fertility problems, changes in metabolism, and an increased risk of obesity and cancer – yet so much still remains unknown about their long-term consequences.Įroded by the elements or dumped down drains, PFAS end up in the water system. PFAS have been found in human breast milk and the blood of 97% of Americans. Renovations will not last for ever but PFAS persist and accumulate in soil, water, air, wildlife and our bodies. PFAS’ incredibly strong carbon-flourine bonds mean these chemicals do not biodegrade.
PFAS accumulate in the water system, and hence in wildlife. They are used in the top layer of solar panels, artificial grass and firefighting foams.Īnglers at Island Lake in Michigan are warned not to eat fish from the Huron River. Used in everything from cosmetics to food packaging, PFAS also show up in paint (as a binding agent and to give a smooth finish), wood lacquers (for repelling oil and water, and stain resistance) and sealants.
This group of synthetic chemicals are used to prevent corrosion, reduce friction and make products waterproof and stain-resistant.
Many of these items rely for their seemingly magical properties on PFAS (per- and polyfluoroalkyl substances), known as “forever chemicals”. Masonry paint is no longer just about the colour: do I need pure brilliant or ultra-smooth, anti-mould or weatherproof? Fence treatments are UV resistant and rainproof within half an hour and protect against rot. Glossy varnishes promise to colour wood for five years.
That means a trip to the DIY store, where the shelves are full of marketing appeals. Soon it will be time to render the exterior with sand and cement, to seal and waterproof the walls, to varnish the new fencing, and finish it all off with a shiny coat of paint. The breeze-block walls have been built, soffits are in place under the eaves, the concrete floor has been poured and slate tiles are being fixed on to the roof. F or months I’ve been watching the construction of our new garage.