Evaluation of Exposure to Bisphenol A, Bisphenol F, and Phthalates in Patients with Phenylketonuria and Its Differences According to Dietary Status.

BACKGROUND

Phenylketonuria (PKU) is the most common amino acid metabolism disorder. Patients with blood phenylalanine (Phe) levels of ≥6 mg/dL require treatment, and the most definitive treatment is the Phe-restricted diet. Bisphenols and phthalates are widely used endocrine-disrupting chemicals (EDCs) found in personal care products, baby bottles, and food packaging.

METHODS

In this study, we evaluated the possible routes of exposure to these EDCs in patients diagnosed with PKU (n = 105, 2-6 years of age) and determined the relationship between the plasma levels of bisphenol A (BPA), bisphenol F (BPF), di-butyl phthalate (DBP), di-(2-ethylhexyl) phthalate (DEHP), mono-(2ethylhexyl) phthalate (MEHP), and dietary regimens. Participant characteristics and exposure routes were evaluated according to their dietary treatment status.

RESULTS

Thirty-four of these patients were on a Phe-restricted diet, while the remaining 71 had no dietary restrictions. DBP and DEHP levels were higher in those using plastic tablecloths ( = 0.049 and = 0.04, respectively). In addition, plasma DBP levels were higher in those who used bottled water ( = 0.01). Being under 4 years of age, using plastic food containers, and using plastic shower curtains were characteristics associated with higher MEHP levels ( = 0.027, = 0.019, and = 0.014, respectively). After adjustment for baseline characteristics (Model 1), the odds of having a plasma BPA level in the upper tertile were 3.34 times higher in the free-diet group (95% CI = 1.09-10.25). When we additionally adjusted for plastic exposure (Model 2), the odds ratio was found to be 18.64 (95% CI = 2.09-166.42) for BPA. In the free-diet group, the probability of having plasma DEHP levels in the upper tertile was increased by a relative risk of 3.01 ( = 0.039, 95% CI = 1.06-8.60).

CONCLUSION

Our results indicate that exposure to bisphenols and phthalates varies with dietary treatment. The difference in sources of exposure to EDCs between the diet and non-diet groups indicates that diet plays an important role in EDC exposure.