Aldehyde contamination of mineral water stored in PET bottles.

Aldehyde contaminations that might accompany production of mineral water stored in PET bottles were investigated. One of the production lines of carbonated mineral water in Poland was monitored and PET bottles commonly used for mineral water storage were evaluated. Formaldehyde and acetaldehyde were the most important carbonyls identified in series of bottled water samples, but also propanal, nonanal and glyoxal were found in water samples from the production line. Aldehydes are present everywhere in the environment and can be determined even in pure water at low microg l(-1) levels. It was observed that the concentration of acetaldehyde in water stored in PET bottles depended mainly on the concentration of acetaldehyde in PET material and could reach more than 200 microg l(-1). The temperature, time of storage and concentration of carbon dioxide gas contribute to the migration of aldehydes from bottle walls to mineral water. Higher pressure of the carbonated waters and not CO(2) itself or lower pH of waters seems responsible for higher concentration of acetaldehyde.

Investigation of carbonyl compounds in bottled waters from Poland.

Poly(ethylene terephtalate) (PET) bottles are commonly used for storing mineral water. The migration of carbonyl compounds from PET bottles into mineral water was observed. Carbonation of water, sunlight and high temperature enhance the process of migration. Formaldehyde, acetaldehyde and acetone were the most important carbonyls identified in series of bottled water samples. The concentration of carbonyls can change depending on the time of storage as well as storage conditions. It was identified particularly high concentration of acetaldehyde (more than 100 microg 1(-1)) in samples of mineral water saturated with CO2 gas.