Scientists have known for years that phthalates can adversely affect male fetal development. Now, a new meta-study finds that phthalates are correlated with a wide variety of chronic diseases in every demographic, including women and children.
Phthalates are a group of synthetic compounds often used to make plastics more flexible. They are ubiquitous in the environment, in everything from personal care products, food packaging, printing inks, fragrances, adhesives and even medical tubing.
The research team that published the new meta-study included an American, a biologist at University of Gothenburg in Sweden, and three researchers in Switzerland.
The team compiled more than three dozen studies on the health effects of phthalates to reveal a wide array of chronic diseases linked to the chemicals — links that until now have been largely ignored for risk assessment. These health hazards include diabetes, obesity, and even mental and behavioral problems.
The US Food and Drug Administration still considers phthalates safe in food and cosmetics.
Among other things, the collected studies identified a relationship between phthalates and the human body’s ability to regulate metabolism, noted PhD biologist and independent consultant Maricel Maffini, who led the research team.
Phthalates may be related to an overall increase in body mass index and waist circumference because they increase the accumulation of adipose tissue, or body fat. The researchers also found an association between phthalate levels and a reduction in the levels of thyroid hormones the body produces.
In addition, Maffini adds, phthalates appear to work against how our muscles use energy. Instead of using energy in the muscles, energy accumulates as fat tissue. The research also highlights studies that show a connection between phthalates and insulin resistance in children and adults — that is, diabetes or diabetes-like conditions.
Most studies don’t usually look at these types of effects, Maffini points out. They tend to focus mainly on phthalates’ effect on male reproduction, which indicates to her that scientists and regulators need to do a much better job of assessing the overall risks of chemicals.
For example, Maffini notes, the researches were surprised to us to see how little phthalate exposure is needed to effect the ovaries.
“Women were having fewer eggs in their ovaries, and children born to mothers exposed to the higher levels of phthalates were found to have behavioral problems — problems with learning, lower IQ, or decreased abilities to make decisions, or motor skills with their hands and their movements,” she says.
"[W]hen you have chemicals that are acting in similar ways or interfering with the function of hormones, you don't need much to see an effect.”
Natural hormones like androgens, estrogens, thyroid hormones, and insulin are incredibly effective information signaling molecules, Maffini explains, “so when you have chemicals that are acting in similar ways or interfering with the function of hormones, you don't need much to see an effect.”
The researchers also raise the possibility that phthalate exposure could have an effect on mental health. These findings are primarily related to children who are exposed to phthalates during brain development.
Brain development, like any other organ, must follow a specific sequence, Maffini explains. Everything has to happen in an orderly way, at a particular time, for a particular duration, in order for cells to develop, proliferate and differentiate into the different parts of the brain and to be located in specific areas of the brain, so the correct connections can form.
“When things don't go the correct way during brain development, you cannot go back and rewire the brain,” Maffini points out. “So, we are seeing issues with children when it comes to behavior, when it comes to learning disabilities, when it comes to delinquency, that are associated with phthalates and mostly with the phthalates in the mom.”
Depending on the trimester in which the mother is exposed and which organs are developing at that particular time, the researchers can see these effects in the children.
Making people aware of how these chemicals impact our bodies is “just our way to show the concerns and the problems with the way we do risk assessment and manage chemical exposures,” Maffini says. “[T]hese are just five of the large families of phthalates and of a much larger chemical soup in which we are all living.”
In the US, the Food and Drug Administration regulates chemicals in food, but does not have limits on phthalate levels in the food supply. The Consumer Product Safety Commission places limits on phthalate levels in children's toys and other articles used by children, like soft plastic rings and rubber duckies.
But here's the problem, Maffini says: These agencies do a risk assessment for each individual chemical, but these chemicals are all alike, so they should be regulated as a class.
A manufacturer might eliminate one phthalate because of a regulation, but use a different one that has the same function, and the manufacturer will be in compliance, even if the new chemical is just as damaging, but has not yet been regulated.
“We [must] start regulating chemicals that are similar and have similar health effects and…have a safe dose for all of them, not a safe dose for each individual [chemical]."
“We [must] start regulating chemicals that are similar and have similar health effects and…have a safe dose for all of them, not a safe dose for each individual [chemical]," Maffini maintains. "If we reduce the exposure levels, we will be better off and it will be more efficient.”
In addition, she adds, health care professionals and regulators need to start talking to one another.
“At the beginning, when a chemical is going to get into commerce, there are regulators looking at the information that companies provide to show that the chemical use is going to be safe,” Maffinia explains. “On the other end, you have the health care providers [who] see people — they see their struggles, they see their health problems, they see dysfunctions of organs, they see behavioral problems, and most of the things [they see] do not have a genetic component… So, they start to look at what is in their environment. What is in the house? What do they eat? Do they have lead paint in the houses? Those type of things. And they generate some of the information that then we use in our paper. But the health care professionals and the regulators don't talk to each other.”
This huge amount of human data should be informing the regulations, Maffini says. And until we understand it and act upon it, very little is going to change.