Human health impact of endocrine disruptors: time to regain our stolen future!
In the latter half of the 20th century, humans have produced various synthetic chemicals, several of which had serious adverse effects on ecosystems and human health. Colborn et al. noticed that some chemicals disrupt the hormonal system of living organisms. They named these chemicals endocrine-disrupting chemicals (EDCs) and published the book Our Stolen Future. In classical toxicology, toxins directly act on cellular components, such as proteins, DNA, and cell membranes; cause damage and exhibit toxicity; and demonstrate a linear dose-response relationship, thus allowing safe thresholds. EDCs transmit abnormal signals through receptors, thus causing errors in the timing, type, and quantity of gene expression, which lead to adverse effects. Through the hormonal signaling system, EDCs can exhibit hormone-disrupting effects even at low doses, thus making it difficult to establish clear thresholds. EDCs have been reported to cause adverse effects by disrupting the estrogenic, androgenic, thyroid, and other signaling systems. Therefore, EDCs affect not only the endocrine system but also the reproductive, nervous, and immune systems. Owing to the wide-ranging effects of EDCs, there is no standardized definition of EDCs, and further research is needed to scientifically clarify EDCs. However, there are accumulating reports on the health hazards to humans caused by EDCs. Considering the precautionary approach, regulations regarding EDCs need to be reevaluated at both the national and international levels. This review introduces and discusses recent research and public initiatives related to EDCs. Can "our stolen future" be regained?