Endocrine disruption: Fact or urban legend?

Abstract

Endocrine disruptors (EDs) are substances that cause adverse health effects via endocrine-mediated mechanisms in an intact organism or its progeny or (sub) populations. Purported EDCs in personal care products include 4-MBC (UV filter) or parabens that showed oestrogenic activity in screening tests, although regulatory toxicity studies showed no adverse effects on reproductive endpoints. Hormonal potency is the key issue of the safety of EDCs. Oestrogen-based drugs, e.g. the contraceptive pill or the synthetic oestrogen DES, possess potencies up to 7 orders of magnitude higher than those of PCP ingredients; yet, in utero exposure to these drugs did not adversely affect fertility or sexual organ development of offspring unless exposed to extreme doses. Additive effects of EDs are unlikely due to the multitude of mechanisms how substances may produce a hormone-like activity; even after uptake of different substances with a similar mode of action, the possibility of additive effects is reduced by different absorption, metabolism and kinetics. This is supported by a number of studies on mixtures of chemical EDCs. Overall, despite of 20 years of research a human health risk from exposure to low concentrations of exogenous chemical substances with weak hormone-like activities remains an unproven and unlikely hypothesis.

Elucidating human male germ cell development by studying germ cell cancer

“…In Western countries, human sperm count is steadily declining, while the incidence of testicular dysgenesis syndrome (TDS), involving testicular cancer, cryptorchidism and hypospadias, is risingboth indications might be explained by the exposure to hormonally active substances found in our environment (Jensen et al 1995, Nilsson 2000, Skakkebaek et al 2001, Nohynek et al 2013, Hauser et al 2015. Endocrine disruptors (EDs), i.e.…”

“…Endocrine disruptors (EDs), i.e. phthalates, polychlorinated biphenyls or alkylphenols are small molecules acting like hormones, which can cause adverse health effects (toxicity) via endocrine-mediated mechanisms (Nohynek et al 2013). Several studies suggest their negative influence on reproduction by mimicking/modulating of sex hormones that are secreted by the ovaries or testes (Nilsson 2000).…”

Do deodorants/underarm cosmetics cause cancer?

“…Söz konusu ürünler vücut kremleri, antiperspirantlar, güneşten korunma ürünleri, losyonlar ya da şampuanlar gibi kozmetiklerin yanı sıra, ilaçları ve bazı gıdaları içermektedir 21 23 . Bununla beraber bu çalışma, parabenlerin meme tümörlerine neden olduğunu kanıtlamamıştır 24 .…”

Endocrine Disruptors: a Real Concern for Humans?

“…Despite the numerous scientific publications (9,800 documents surveyed in SCOPUS and 5,200 in PubMed at April 2015) no certainty on the real risk from exposure to EDCs has been acquired and the debate is still alive whether this argument is a legend or a fact [4]. This disagreement is due since: a) the exposure to the same level of an endocrine signal during different life stages may produce different effects; b) the exposure when the "planning" of endocrine system is in progress may result in a permanent change of function or sensitivity to stimulatory/inhibitory signals; c) the exposure during the adulthood can be compensated for by normal homeostatic mechanisms and may therefore not result in significant or detectable effects.…”