Endocrine disruptors are found in many everyday products, including some plastic bottles and containers, liners of metal food cans, detergents, flame retardants, food, toys, cosmetics, and pesticides.
Some endocrine-disrupting chemicals are slow to break-down in the environment. That characteristic makes them potentially hazardous over time. Endocrine disrupting chemicals cause adverse effects in animals. But limited scientific information exists on potential health problems in humans. Because people are typically exposed to multiple endocrine disruptors at the same time, assessing public health effects is difficult.
People may be exposed to endocrine disruptors through food and beverages consumed, pesticides applied, and cosmetics used. In essence, your contact with these chemicals may occur through diet, air, skin, and water. Even low doses of endocrine-disrupting chemicals may be unsafe. Research by Tamarra James-Todd, Professor of Environmental Reproductive and Perinatal Epidemiology, has focused on pregnancy complications such as preterm birth and gestational diabetes, looking at whether endocrine disruptors may play a role.
Using data from two large ongoing cohort studies in the US, the scientists have focused on a particular class of chemicals known as phthalates which are commonly used in cosmetics and food packaging. Alterations of the insulin response leading to diabetes in the general population have also been observed by other research teams, the most robust evidence for this being focused on the action of a chemical known as p,p'-DDE which was used as part of a pesticide.
Other problems resulting from the action of endocrine-disrupting chemicals may include metabolic syndromes and obesity, as well as the promotion of breast, testicle and prostate cancer. Although the evidence is currently more limited, endocrine-disrupting chemicals have also been investigated for their role in immune and autoimmune diseases and for their link to brain development problems.
Today, cosmetics often include a wide range of compounds including fixatives, dyes, and preservatives such as parabens or formaldehyde, metal salts, UV filters, solvents, and fragrance ingredients. Research into the effects of endocrine disruptors have mostly focused on household and agricultural products, but this is a problem that also has to do with cosmetics.
In a new study published in the journal Cosmetics , researchers reviewed the evidence for some of these compounds acting as endocrine disruptors. In a study ever on human amniotic fluid, published in Epidemiology , Ivell and colleagues investigated the effect of phthalates, used to make plastics more flexible, on fetal testes using tens of thousands of samples in a bank set up by scientists in Denmark.
A clear relationship between the load of phthalate compounds within the amniotic fluid and the testes was demonstrated, with the reduction in some hormones produced in direct proportion to exposure.
Disturbing androgen metabolism could negatively influence skeletal, muscle and brain development. Clinicians can look to epidemiology to observe relationships between EDCs and numerous conditions, Bourguignon said, including testicular, breast and prostate cancers, along with obesity, diabetes and metabolic syndrome.
In a review published in Endocrine Reviews , Lee and colleagues summarized epidemiologic results on POPs, with evidence suggesting that background exposure to chemical mixtures is more likely responsible for increased type 2 diabetes risk than a few specific chemicals.
These are likely epigenetic changes that can last for the whole life. Endocrinologists now recognize the severity of consequences potentially stemming from alterations in DNA, particularly during early life, trumping a previous belief in the adjustment capacity of human physiology, Bourguignon said.
The first-ever clinical guidance on EDCs, along with human health impact, hormone action considerations, mechanisms, and disease trends will also be covered in the chapter, co-written by Zoeller. From a practice standpoint, Zoeller said endocrinologists must recognize that EDCs are not subspecialty-specific.
The mosaic effect that is produced by some of these chemicals will trick us. Certain EDCs are already on the radar, but the various chemical classes could contain dozens to hundreds.
Gore is now working on the second Scientific Statement of the Endocrine Society on EDCs, anticipated for release in late , building on the first statement from The focus to-date has been on estrogen, androgen and thyroid hormone receptors, but other types of signaling systems that EDCs act upon are just beginning to be studied.
Boosting translation from in vitro cell line and tissue work to animal models, to make stronger connections to humans, is another focus. Sheep and nonhuman primates are being used more often. With new chemicals continually in development, the scientific statement will underscore the need for expeditious research and identification of EDCs.
Ultimately, what drives policymakers is what is coming from citizens. But he noted concerns must not be dismissed. Neither panic nor rejection will best serve public health, Bourguignon said. The global community must remain grounded and engaged. We should go beyond fear. As a pediatric endocrinologist, I am often asked about EDCs by patients.
Pubertal development, including concerns about precocious puberty or early normal puberty, raises questions from families the most.
I discuss EDCs with these families because there is evidence suggesting that pure lavender oil and tea tree oil, commonly found in skin care products, are associated with gynecomastia in prepubertal boys and in other models. When a young girl presents with premature breast development, I always ask about these exposures. A strong connection is also seen between paternal use of certain androgen-containing creams and premature pubarche or hirsutism. When I see children with early pubic hair or atypical polycystic ovary syndrome, I always ask about household androgen exposure.
Generally, I let patients ask me about endocrine disruptors, but for those two chief complaints — premature breast development and premature pubarche — I ask about these main exposures because the evidence is so strong linking the exposure to the negative health outcome.
For many other chemicals, relationships are more challenging to pinpoint, due to the latency of effect and dose variability. If EDC exposures are significant, it helps me with my workup and evaluation. Asking the question elicits the counseling. Many people now know the dangers of exposures, but most people do not.
0コメント