Phthalates have been reported to affect the function and growth of thyroid. However, there is little data on the effect of phthalates on thyroid
oncogenesis. Here we explored the associations between phthalates exposure and the risks of
thyroid cancer and benign nodule. We sex-matched 144
thyroid cancer, 138 benign nodule patients and 144 healthy adults from Wuhan, China. Eight
phthalate metabolites in spot urine samples were quantified using high-performance liquid chromatography and tandem mass spectrometry. The associations of
creatinine-corrected urinary
phthalate metabolites with the risks of
thyroid cancer and benign nodule were assessed using multivariable logistic regression models. We found that urinary
monomethyl phthalate (
MMP), mono(2-ethyl-5hydroxyhexyl)
phthalate (MEHHP) and mono(2-ethylhexyl)
phthalate (
MEHP) associated with increased risks of
thyroid cancer and nodule, with adjusted odds ratios (
ORs) ranging from 1.74 to 4.78 comparing the extreme tertiles, and urinary
monobutyl phthalate (MBP) was associated with decreased risks of
thyroid cancer and benign nodule (all P for trends < 0.05). Male-specific positive associations of urinary
monoethyl phthalate (MEP) with
thyroid cancer and nodule as well as urinary
mono(2-ethyl-5-oxohexyl) phthalate (MEOHP) with
thyroid cancer were also observed. Our results suggest that exposure to certain phthalates may contribute to increased risks of
thyroid cancer and benign nodule.