Research progress on food-derived antioxidants for alleviating toxicity of endocrine disrupting chemicals / 环境与职业医学

Endocrine disrupting chemicals (EDCs) are a class of chemical substances widely present in daily-life environment, and can enter human body through various pathways, posing a threat to reproductive development and health. Oxidative stress (OS) is one of the most important fundamental mechanisms underlying the reproductive toxicity of EDCs. Numerous studies have found that exposure to EDCs can increase the levels of reactive oxygen species (ROS) in human reproductive system and reduce the activity and quantity of multiple enzymatic antioxidants, leading to oxidative stress and inducing damage to the reproductive system at various levels such as DNA and cells. Many research results have shown that supplementing food-derived non-enzymatic antioxidants can reduce ROS levels and increase the activity of enzymatic antioxidants, thereby reduce OS levels, and further repair EDCs-induced reproductive damage. In addition, many food-derived antioxidants are important elements involved in reproductive physiological activities and have protective effects on reproductive health. This paper summarized the reproductive toxicity of EDCs, including damage to reproductive cells, interference with hormone action, and influence on reproductive-related epigenetic regulation, elaborated the relationship between OS and reproductive toxicity of EDCs, and further summarized the alleviating effects and related mechanisms of food-derived antioxidants such as vitamins, trace elements, and plant polyphenols and pigments against reproductive toxicity of EDCs, aiming to provide a theoretical and scientific basis for prevention and treatment against reproductive toxicity of EDCs.

Relationship between triclosan exposure and thyroid hormones: the Second Korean National Environmental Health Survey (2012–2014)

BACKGROUND: 5-chloro-2-(2,4-dichlorophenoxy)phenol (triclosan) is used as an antiseptic and is a potential endocrine-disrupting chemical that can affect thyroid hormone levels. This study evaluated the relationship between triclosan exposure and thyroid hormones. METHODS: Data from the second Korean National Environmental Health Survey (2012–2014) were analyzed. Triclosan exposure was evaluated using urinary triclosan concentrations and classified into 2 groups: ‘below detection (< limit of detection [LOD])’ vs. ‘detected (≥ LOD).’ Multiple linear regression analysis was conducted to determine the relationship between triclosan exposure and the serum thyroid hormone concentrations, adjusting for age, body mass index, urinary creatinine, and smoking status. RESULTS: When grouped by sex, triclosan exposure was positively associated with the serum thyroid-stimulating hormone (TSH) concentrations in females with marginal significance (β = 0.066, p = 0.058). However, no significant association was identified between triclosan exposure and serum total triiodothyronine and thyroxine in both males and females, and TSH in males. CONCLUSIONS: This study is the first human study to evaluate the relationship between triclosan exposure and serum thyroid hormone concentrations in the Korean population. There was suggestive positive association between triclosan exposure and the serum TSH in females. Further studies need to evaluate the relationship between long-term exposure to low-dose triclosan and thyroid hormones.

Influence of Bottle-Feeding on Serum Bisphenol A Levels in Infants

Exposure to endocrine disrupting chemicals (EDCs), particularly during developmental periods, gives rise to a variety of adverse health outcomes. Bisphenol A (BPA) is a well-known EDC commonly found in plastic products including food and water containers, baby bottles, and metal can linings. This study investigates infant exposure to BPA and the effect of bottle-feeding on serum BPA levels in infants. Serum BPA levels in normal healthy infants 6 to 15 months of age (n=60) were evaluated by a competitive ELISA. BPA was detected in every study sample. Serum BPA levels of bottle-fed infants (n=30) were significantly higher than those of breast-fed infants (n=30) (96.58+/-102.36 vs 45.53+/-34.05 pg/mL, P=0.014). There were no significant differences in serum BPA levels between boys (n=31) and girls (n=29). No significant correlations were found between serum BPA levels and age, body weight, birth weight, and gestational age. Bottle-feeding seems to increase the risk of infant exposure to BPA. Establishment of health policies to reduce or prevent BPA exposure in infants is necessary.