ESPE Abstracts

Background: Recently, the puberty is becoming to start earlier. This early beginning of the puberty is multifactorially related to genes, hormones and environmental factors. It has been already known in many animal experiments that endocrine disrupting chemicals (ECDs) are deeply envolved in regulation of endocrine systems. However, clinical studies in humans are limited. Recently, the toy of 'Slim' which thought to contain ECDs such as phthalates is very popular in primary school children. This study was done to see the effect of ECDs in primary school children's puberty.

Materials & Methods: Study patients consisted of 140 children whom GnRH stimulation tests were done due to precocious puberty between Jan 2018 and Dec 2018. Twenty-seven boys (19%) and 113 girls (81%) were enrolled. Precocious puberty was defined when the first pubertal sign began below the age of 8 yrs in girls and 9 yrs in boys along with the advanced bone age ≥ 1 yr. GnRH stimulation tests were performed in all study patients. Study patients were classified into two groups; 'GnRH+ group' (peak LH ≥ 5mU/mL) and 'GnRH- group' (peak LH < 5 mU/mL). The exposure history of ECDs was accepted when study patients play with 'Slim' ≥ 3 times/week for ≥ 6 months at the time of GnRH stimulation tests. BMI, changes of bone-age, auxological data and various laboratory data were retrospectively analyzed.

Results: Fifty-eight (41%) were enrolled in 'GnRH+ group', and 82 (59%) in 'GnRH- group'. Seventy-nine out of 140 (56%) showed a significant exposure history of ECDs; 14/58 (24.1%) in 'GnRH+ group' and 65/82 (79.2%) in 'GnRH- group'. A significant exposure history of ECSs was statistically higher in 'GnRH- group' compared to 'GnRH+ group' (P<0.05). The possibility of GnRHa treatment was 5.55 times higher in patients with significant exposure Hx of ECDs compared to without significant exposure Hx of ECDs (P<0.001). Bone-age advancement was also higher in patients with significant exposure Hx of ECDs compared to without significant exposure Hx of ECDs (P<0.05).

Conclusion: It can be said that the exposure of ECDs seems to be related to the early pubertal onset and rapid bone-age advancement. Further study is necessary.