Associations of phthalate exposure with lipid levels and insulin sensitivity index in children: A prospective cohort study

We performed repeated measurements of phthalate metabolite concentrations during childhood and investigated the association of phthalate exposure with lipid levels and insulin resistance. This study included 164 subjects from the Korean Ewha Birth and Growth Cohort Study who underwent follow-up examinations at 3–5 and 7–9 years of age. We measured nine urinary phthalate metabolites, as well as fasting blood glucose, triglyceride (TG), and high-density lipoprotein-cholesterol (HDL-c) levels and the homeostatic model assessment for insulin resistance (HOMA-IR) value. We found that phthalate levels were higher in children at 3–5 years than at 7–9 years of age. Some phthalate metabolites were associated with increased TG and HOMA-IR levels at both age ranges. Repeated measurements of phthalate metabolites were performed to identify long-term exposure patterns. An increased level of mono(2‑ethylhexyl) phthalate (MEHP) was significantly associated with an increased TG level, and increased levels of MEHP, mono(2‑ethyl‑5‑oxohexyl) phthalate (MEOHP), and monoisononyl phthalate (MiNP) were significantly associated with an increased HOMA-IR value, at both age ranges. An increased level of mono-benzyl phthalate was associated with a decreased level of HDL-c at both ages. Our findings suggest that phthalate exposure during childhood is association with effects in terms of insulin-sensitivity index.