Watch Those Plastic Bottles

There is some data from animal models that BPA does affect fertility.

Leached components from dental composites and their effects on fertility of female mice.

Al-Hiyasat AS, Darmani H, Elbetieha AM

This study investigated the effects of leached components from a resin-based dental composite (Z-100) and bisphenol A (BPA) on female mouse fertility. Leached components or BPA (5, 25 and 100 microg kg(-1)) were administered intragastrically daily to the test and distilled water to the control groups for 28 d. Female mice were then mated with sexually mature untreated males and their fertility was assessed. The results revealed a significant reduction in the number of pregnancies--54.5% vs. 100% (control)--in mice treated with the leached components from the dental composite, which also showed an increase of 142% in relative ovary weights. Exposure to 25 and 100 microg kg(-1) BPA resulted in significant increases in the total number of resorptions out of the total number of implantations and significant increases in relative uterine weights. Relative ovarian weights were significantly increased at the highest dose. High performance liquid chromatography analysis showed that tri-(ethylene glycol)-dimethacrylate (TEG-DMA) was the major leached component (total: 5945 microg ml(-1)) from the composite, followed by bisphenol A glycerolate dimethacrylate (BIS-GMA) (total: 2097 microg ml(-1)) and BPA (total: 78 microg ml(-1)). The results suggest that leached components from the dental composite used and commercially purchased BPA have adverse effects on the fertility and reproductive system of female mice.

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In the US, our exposure isn't reported as problematic though from NHANES data....

Bisphenol A (BPA) daily intakes in the United States: Estimates from the 2003-2004 NHANES urinary BPA data.

Lakind JS, Naiman DQ.

Investigations into human exposure to bisphenol A (BPA) have, for the most part, assessed intake based on food consumption estimates combined with measurements or estimates of BPA in foods. In this study, nationally representative data on urinary levels of BPA in the United States (US) from the 2003-2004 National Health and Nutrition Examination Survey (NHANES) were used to estimate daily intake of BPA, assuming steady-state excretion. Distributions of intakes for the US population were determined for (i) all NHANES participants with urinary BPA data; (ii) participants by the following age groups: 6-11 years, 12-19 years, 20-39 years, 40-59 years, and 60+ years; and (iii) participants by gender. On the basis of the NHANES urinary BPA data and the assumptions described in this paper, daily BPA intakes for male participants are statistically significantly higher than for female participants, and there are statistically significant differences in daily BPA intakes according to age groups, with the oldest group having the lowest estimated intakes. Median intake was approximately three orders of magnitude below health-based guidance values of 50 mug/kg-day.

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Then again....

Xenoestrogens: the emerging story of bisphenol a.

Ben-Jonathan N, Steinmetz R.

Xenoestrogens are chemicals with diverse structure that mimic estrogen. Bisphenol A (BPA), a monomer of polycarbonate and epoxy resins, has been detected in canned food and human saliva. BPA stimulates cell proliferation and induces expression of estrogen-responsive genes in vitro, albeit with a relatively low potency. In vivo, BPA increases prolactin release and stimulates uterine, vaginal and mammary growth and differentiation. BPA shares similarities in structure, metabolism and action with diethylstilbestrol (DES), a known human teratogen and carcinogen. This review considers the hypothesis that BPA is converted in vivo to hydroxylated metabolite(s) with enhanced estrogenicity and genotoxicity.

---> the DES part is downright scary!

I remember when siggs were the only water bottle you could buy - god I'm old.

I wonder what the environmental fallout will be when everyone starts chucking all their plastic bottles out in a panic. As it is, the percentage that gets recycled is really low.