Scientists have found that chemical pollution has exceeded the limits of human safety

One study shows that the cocktail of chemical pollution that pervades the planet now threatens the stability of the global ecosystems on which humanity depends. Among them, plastics and 350,000 synthetic chemicals, including pesticides, industrial compounds and antibiotics, are particularly worthy of high attention.

Plastic pollution is now found from the summit of Mount Everest to the deepest oceans, and some toxic chemicals, such as PCBs, are long-standing and widespread. The study concludes that chemical pollution has crossed the "boundary," where human changes to the planet have pushed it beyond the stable environment of the past ten thousand years. Chemical pollution threatens Earth's systems by disrupting the biological and physical processes that underpin all life. For example, pesticides have eliminated many non-target insects that are the foundation of all ecosystems and therefore the basis for providing clean air, water and food.

Chemical production has increased 50-fold since 1950 and is expected to triple by 2050, and the rate at which societies produce and release new chemicals into the environment is inconsistent with the rate at which they remain in a safe space for humans, the researchers said. It has long been known that chemical pollution is a bad thing. But they haven't thought about it at the global level yet. Some threats have been addressed to a greater extent, such as CFC chemicals that destroy the ozone layer and its protection against destructive ultraviolet rays.

Determining whether chemical pollution has crossed planetary boundaries is complicated because there is no pre-human baseline, which is different from the climate crisis and pre-industrial levels of carbon dioxide in the atmosphere. There are also a large number of registered compounds in which only a very small fraction has been safety evaluated. Therefore, the study used a variety of measurement methods to assess the situation. These include the rate at which chemicals are being produced (which is rising rapidly) and their release into the environment at a rate far greater than the ability of authorities to track or investigate their impact.

The negative effects of some well-known chemicals, from the extraction of fossil fuels to produce them to their spillage into the environment, are also part of the assessment. The scientists acknowledge that data is limited in many ways, but they say the weight of the evidence suggests that Earth's boundaries have been breached. For example, the total mass of plastic now exceeds the total mass of all living mammals, which is a very clear indication that we have crossed a boundary. We're in trouble, but there are things we can do to turn that around.

The researchers say there needs to be more regulation and a fixed cap on chemical production and emissions in the future, just as carbon targets aim to end greenhouse gas emissions. Their study was published in the journal Environmental Science and Technology.