Exchange glass bottles for plastic bottles? After all, we may be drinking even more microplastics.
The French Food Security Agency recently has done several studies to measure microplastics levels in everyday foods, especially in seafood and drinks.
Compared to the glass, the same drinks packed in bottles or plastic cans were five to 50 times less microplastics, challenging the common belief that glass is the safest option.
The scientists of the ANSES laboratory in Boulogne-sur-Mer have discovered a surprising source of microplastic contamination: the ink of the metal lids of the bottles. They suspect that the ink flakes can start from the lids and end in the drinks.
Among the tested drinks, water and wine had fewer microplastic particles than the others.
The evil of metal lids
The reason why microplastics levels vary between beverages remain unknown except in a clear case: Glass bottles with metal lids.
Researchers wanted to confirm how microplastics enter the beverages stored in glass bottles and whether cleaning the bottle caps could help.
As it details A, three scenarios were studied after cleaning the bottles and filling them with filtered water: back to seal the bottles with lids for cleaning, blow air into the lids before sealing them or blew and rinse the lids before sealing them.
The researchers found that:
- as Caps for cleaning released about 287 particles microplastic per liter in bottled water;
- blow on the lids reduced this value to 106 particles per liter;
- blow air and rinse with water and alcohol reduced even more to 87 particles per liter.
The main clues that the bottle caps paint may be the source of contamination include:
- a correspondence between color and composition of paint particles of the lids found in the drinks;
- Small risks on lidsprobably caused by friction during storage;
- release of too small flakes to be seen – indicating that the paint layer itself, not the bottle material, is the main source of microplastics.
