This study should bother everyone. It found that certain chemicals were being absorbed by the ovaries.
For several years now, phthalates, dangerous chemicals found in various plastic and care products, have been marked as a possible cause of the general decline in fertility around the world. Now Israeli researchers have discovered that these chemicals are being absorbed into women's ovaries. What does this mean?
In recent years, there has been an alarming phenomenon of a significant decrease in fertility throughout the Western world, and about 15% of all women are unable to become pregnant without medical assistance.The reasons for this are varied, and include, among other things, exposure to a wide range of chemicals from various sources which disrupt the body’s natural hormonal activity.
A new and groundbreaking Israeli study found that one group of chemicals called phthalates, which are in so many plastics, cosmetics and other consumer products that it’s almost impossible to avoid them completely, are being stored in women’s ovaries.
Phthalates are a family of synthetic chemicals developed in the last century for use in plastics manufacturing industries (mainly for softening and increasing flexibility), solvents and care products, and are therefore found in a wide range of products we use daily such as plastic packaging (including food packaging), cosmetics, building materials, cleaning products, pesticides, fragrances, toys, paints, medical devices and textiles. In fact, phthalates are so common that they have been dubbed the "ever-present chemical."
Phthalates are considered endocrine-disrupting compounds (EDCs), substances that mimic or inhibit the activity of various hormones in humans and thus disrupt normal hormonal activity, which impairs, among other things, the fertility of men and women.
Over the years, scientific evidence has accumulated that shows that phthalates have various negative effects on everyone's health. This has been shown in experiments on animals where they were found to cause numerous hormonal disorders such as impaired development of the male reproductive system, congenital malformations of the reproductive system and genitals, lower testosterone levels in the stages of puberty, premature puberty in females and low sperm count as well as low birth weight and premature birth.
Research also showed a link to impaired development of the male reproductive system, impaired brain development and an increased risk of developing learning disorders, attention and behavior problems and delayed language development in babies. As a result, various doctors and experts in the field have called for a total ban on the incorporation of phthalates in consumer products, in particular in cosmetics and toys, to which pregnant women and children are exposed.
The negative effect of phthalates on fertility
In recent years, knowledge has been accumulating about the negative effect of phthalates on female fertility.
In 2017, a previous study was conducted by scientists at Sheba Medical Center, including by some researchers who also conducted the current study. Some 136 women who underwent in vitro fertilization (IVF) participated. Seventeen different metabolites of phthalates (phthalates that underwent a certain breakdown in the body) were found in the subjects' urine.
The researchers discovered that the amount of eggs that were matured as part of the preparatory treatment for fertilization, as well as the amount of eggs that were successfully fertilized and became embryos, were lower when there was a higher concentration of three of the decomposition products of the phthalates in the urine of the women tested.
In the new study, recently published in the scientific journal Human Reproduction, researchers tried to understand exactly how phthalates affect female fertility. The study is an international collaboration of researchers from Sheba Medical Center, Ruppin Academic Center and Harvard and Columbia Universities in the United States. It was led by Prof. Ronit Mechtinger, senior physician in the IVF Unit at Sheba and Dr. Zohar Brent-Yitzhaki of the Faculty of Engineering and the Health Informatics Center at Ruppin Academic Center.
The researchers looked for evidence for the presence of phthalates in follicular fluids that surround the egg when it’s inside the ovarian follicle before ovulation.
They relied on samples collected from 105 women doing IVF at Sheba. The results weren’t encouraging: Of the 12 different types of phthalate metabolites tested, 11 were found in at least one sample. In the follicular fluid of 76% of the women, seven different types of phthalate metabolites were found simultaneously, and in five of the subjects, no less than 10 different phthalate metabolites were seen.
Only in two women there were no metabolites of phthalates found in their follicular fluids.
Synthetic chemicals in the most sensitive place
"The findings of the study should bother us all," said Brent-Yitzhaki.
Man-made chemicals have been found in one of the most sensitive places in the body. According to him, the situation should be completely reversed.
He also believes that the area around the egg must be as clean as possible so that humanity can continue to reproduce properly and not become extinct. In this study we discovered phthalates that are known to affect the egg maturation process and disrupt female fertility. This is a very significant first finding.
How do phthalates reach the depths of the female reproductive system?
Phthalates from the many consumer products (for example cosmetics) to which people are exposed enter the body through food, through drinking, or even via the air we breathe. Phthalates are in the air and also in the dust, explains Brent-Yitzhaki.
"Previous studies have found phthalates in the blood, and it’s hypothesized that they’re transmitted through the bloodstream to various organs and areas in the body including the ovaries,” he said.
A crucial role in egg development
According to the study, phthalates may affect fertility through their effect on microRNAs, molecules used to control gene expression in cells, which are found in the follicular fluid. Brent-Yitzhaki said that he’s speaking about dozens to hundreds of molecules, some of which play a crucial role in egg development, maturation and fertilization.
The researchers isolated the microRNA from the follicular fluids.
According to Brent-Yitzhaki, in the statistical calculations made, it was found that there was a relationship between the appearance of particular phthalates in the follicular fluid and the levels of different micro-RNA molecules in the follicular fluid and the genes they control.
He states that the invention of phthalates has been linked to the concentration of 39 different micro-RNA molecules, which affect a total of 304 genes related to female fertility (for example, ovarian development, eggs, egg maturation).
"Thus, environmental exposure to chemicals may harm biological pathways associated with female fertility,” he said.
Brent-Yitzhaki concluded that it’s important to note that phthalates are only one group of chemicals.
All chemicals to which we are exposed affect our health, so the role of phthalates is a significant and disturbing discovery, but there are many other chemicals whose effects must be investigated.