Development and Applications of a Simple Spectrophotometric Method for Determination of Bisphenol A in ‘New’ and ‘Used’ Polycarbonate Baby Feeding and Water Bottles

Abstract

Recently endocrine disorders have become a big concern. Endocrine-disrupting chemicals are contaminants interfering with hormone biosynthesis, metabolism, or change how the endocrine system works. Bisphenol A is an endocrine disruptor having weak estrogenic activity and competes with body native estrogen. Polycarbonate containers are known to be major sources of bisphenol A that leaches to the container’s content through hydrolysis. This study aimed at monitoring levels of bisphenol A exposure to polycarbonate users through a novel spectrophotometric technique. The polycarbonate samples used were baby feeding bottles and portable water bottles. The Spectroscopic method employed a diazotization reaction procedure resulting in the formation of yellow azo-dye that is easily detected using UV-Vis spectroscopy. Prior to use, the sampled ‘suspected’ polycarbonate bottles were verified to be Polycarbonate using Fourier transform infrared spectroscopy.The Fourier transform infrared spectra of thin plastic solids were identified by scanning between, 500-4000 cm^-1 for characterization. The resulting spectra were compared with those of standard polycarbonate plastics reported in the literature. Characteristic polycarbonate peaks at 2970, 1970, 1504, 1187, 1013, 1079 cm^-1 associated with the –C-H, C=O, C=O, O-C-O, -CH₃ stretching vibrations respectively confirmed sampled bottles were polycarbonates.  Bisphenol A levels for all the sampled polycarbonate bottles in the various environments ranged between 0.17 – 2.82 µgmL^-1.  All the samples surpassed the tolerable daily intake for BPA of 4 ?g/kgbw/day recommended by the European Food Safety Authority and this calls for serious consideration.