The Migration of Phthalate Esters in High Density Polyethylene/Polyethylene Terephthalate Packaged Water At Different Storage and Environmental Conditions in Lagos Metropolis

Abstract

The demand for potable drinking water is met by production, marketing and consumption of water packaged in polyethylene terephthalate (PET) bottles and high-density polyethylene (HDPE) sachets. This study investigated the effects of temperature and storage time on the concentration of phthalate esters (PAEs) leached into packaged drinking water purchased in Lagos, Nigeria. Water samples were collected from factories as soon as they were produced,  stored for 30 days indoors at 23-27 ^oC and outdoors at 31- 33 ^oC. Using Liquid-Liquid Extraction, the PAEs were extracted with dichloromethane and quantified with an Agilent 6890 Gas  Chromatograph coupled with Flame Ionization detector (GC-FID). Five phthalate esters, namely: dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DnBP), benzyl butyl phthalate (BBP) and di (2-ethylhexyl) phthalate (DEHP) were detected in the packaged waters. The obtained results show an elevation in the concentration of PAEs because of storage time and condition. The range of PAEs was found to be 0.03µg/L to 7.76 µg/L with DEHP being the most frequently detected phthalate in the drinking water samples. The highest concentrations obtained for DEHP was found to be slightly above the United States Environmental Protection Agency (USEPA)), Maximum Contaminant Level (MCL) set for DEHP in drinking water which is 6 µg/L. The results obtained in this study confirmed the possible leaching of PAEs into the drinking water samples from the packaging materials, with concentrations that are dependent on the storage time and the temperature at which the samples were stored. It is recommended that drinking water that is packaged in high density polyethylene or polyethylene terephthalate should not be stored for extended time and efforts should be made to store them at lower temperatures