Dietary exposure assessment of infants to bisphenol A from the use of polycarbonate baby milk bottles

Abstract

The residual bisphenol A (BPA) levels in 28 different brands of polycarbonate (PC) baby milk bottles available in the Singapore market were measured. With a detection limit of 3 mg/kg, BPA residues were detected in 19 out of the 28 PC baby milk bottles at levels between 4.01 and 141 mg/kg, with a mean of 28.1 +/- 31.4 mg/kg and a median of 17.2 mg/kg. The potential migration of BPA from each of the 28 PC milk bottles was also measured using food-simulating solvents and time conditions recommended by the US Food and Drug Administration (US FDA), but using temperatures more severe than actual use. The highest upper-bound mean BPA migration levels of 0.64 +/- 0.48 microg/in2 in 10% ethanol at 70 degrees C and 0.43 +/- 1.25 microg/in2 in corn oil at 100 degrees C were observed after incubating cut portions of the milk bottles for 240 h. With this migration data and using US FDA's procedure for estimation of dietary exposure, the worst-case dietary exposure assessment for the intake of BPA by infants between birth and three months of age was below the oral Reference Dose of 0.05 mg/kg bw/day established by the US Environmental Protection Agency. This study showed that the dietary exposure to BPA from actual uses of PC milk bottles is unlikely to pose a health risk in infants.

Perinatal exposure to the xenoestrogen bisphenol-A induces mammary intraductal hyperplasias in adult CD-1 mice

“…BPA has been detected in human breast milk [20,21], polycarbonate baby bottles [60], and in some infant formulas, likely due to the packaging materials used [61,62]. Average exposure of bottle-fed newborns to BPA was estimated at 24 μg/kg BW/day, and 15 μg/kg BW/day for infants at 3 months of age [60].…”

“…BPA has been detected in human breast milk [20,21], polycarbonate baby bottles [60], and in some infant formulas, likely due to the packaging materials used [61,62]. Average exposure of bottle-fed newborns to BPA was estimated at 24 μg/kg BW/day, and 15 μg/kg BW/day for infants at 3 months of age [60]. Human infants produce glucuronidases in their digestive tracts with increased production until adult levels are reached at four years of age [63] suggesting that conjugated BPA may be deconjugated and activated during the digestion process.…”

Environmental causes of cancer: endocrine disruptors as carcinogens

“…60 Exposure to BPA in the human fetus occurs through maternal exposure, and in the neonate through ingestion of maternal milk, tinned food and infant formula. 61–63 …”

Polycarbonate Bottle Use and Urinary Bisphenol A Concentrations

“…High temperatures as well as acidic and alkali solutions cause polymer degradation via hydrolysis, resulting in increased BPA migration. After incubation for 8, 72, and 240 hr in food-simulating solvents (10% ethanol at 70°C and corn oil at 100°C), mean BPA migration increased with incubation time (Onn Wong et al 2005). After a sequence of washing and rinsing, Le et al (2008) found that new poly-carbonate bottles leached 1.0 ± 0.3 μg/mL BPA (mean ± SD) into the bottle content after incubation at room temperature for 7 days.…”