The cocktail of chemical pollution that pervades the planet now threatens the stability of global ecosystems upon which humanity depends, scientists have said.
Plastics are of particularly high concern, they said, along with 350,000 synthetic chemicals including pesticides, industrial compounds and antibiotics. Plastic pollution is now found from the summit of Mount Everest to the deepest oceans, and some toxic chemicals, such as PCBs, are long-lasting and widespread.
The study concludes that chemical pollution has crossed a “planetary boundary”, the point at which human-made changes to the Earth push it outside the stable environment of the last 10,000 years.
Chemical pollution threatens Earth’s systems by damaging the biological and physical processes that underpin all life. For example, pesticides wipe out many non-target insects, which are fundamental to all ecosystems and, therefore, to the provision of clean air, water and food.
“There has been a fiftyfold increase in the production of chemicals since 1950 and this is projected to triple again by 2050,” said Patricia Villarrubia-Gómez, a PhD candidate and research assistant at the Stockholm Resilience Centre (SRC) who was part of the study team. “The pace that societies are producing and releasing new chemicals into the environment is not consistent with staying within a safe operating space for humanity.”
Dr Sarah Cornell, an associate professor and principal researcher at SRC, said: “For a long time, people have known that chemical pollution is a bad thing. But they haven’t been thinking about it at the global level. This work brings chemical pollution, especially plastics, into the story of how people are changing the planet.”
Some threats have been tackled to a larger extent, the scientists said, such as the CFC chemicals that destroy the ozone layer and its protection from damaging ultraviolet rays.
Determining whether chemical pollution has crossed a planetary boundary is complex because there is no pre-human baseline, unlike with the climate crisis and the pre-industrial level of CO2 in the atmosphere. There are also a huge number of chemical compounds registered for use – about 350,000 – and only a tiny fraction of these have been assessed for safety.
So the research used a combination of measurements to assess the situation. These included the rate of production of chemicals, which is rising rapidly, and their release into the environment, which is happening much faster than the ability of authorities to track or investigate the impacts.
The well-known negative effects of some chemicals, from the extraction of fossil fuels to produce them to their leaking into the environment, were also part of the assessment.
The scientists acknowledged the data was limited in many areas, but said the weight of evidence pointed to a breach of the planetary boundary.