Center for Research on Ingredient Safety

In this series, we explore endocrine disrupting chemicals (1,2). In this post, we look at a group of chemicals identified as having endocrine disrupting properties, phthalates.

What are endocrine disrupting chemicals?

Endocrine disrupting chemicals are compounds that can interfere with maintaining the appropriate balance of our hormones by either changing the amount of hormone being made or by mimicking the biological action of a hormone. However, this does not mean endocrine disrupting chemicals all cause harm.
 
Endocrine disrupting chemicals like the kind found in prescribed pharmaceuticals can be incredibly beneficial to the recipient and are typically referred to as “endocrine acting.” For example, birth control pills can either contain the hormones progestin and estrogen or progestin-only, both of which are also naturally made in women's ovaries. By artificially changing the amount and timing in the rise of these two hormones by taking a pill, women can avoid pregnancy. Birth control can also help with specific medical conditions. 

However, endocrine disrupting chemicals such as contaminants found in large enough quantities that are not prescribed and monitored by a healthcare professional have the potential to cause great harm to the body and we can face a number of adverse health outcomes such as reproductive health issues, cognitive deficits, obesity, and can potentially contribute to cancer (1).

What are phthalates?

Phthalates, frequently called plasticizers, are a group of compounds that give many plastics their key flexibility characteristics (1).

Are all phthalates the same?

No, phthalates encompass a diverse group of compounds and not all phthalates possess the same properties and safety ratings.
 
Meaning, some phthalates may not cause harm to human health and other phthalates may cause adverse health outcomes (1,2).

It’s important to understand that different compounds in the phthalate family may cause different outcomes.

Where do we find them?

We find these ingredients in many daily products we use such as toys, vinyl flooring, detergents, lubricating oils, food packaging, pharmaceuticals, medical equipment, and personal care products, such as nail polish, hair sprays, fragrances, and more (1,2). 

Do they harm our health?

As we have discussed in previous blogs (1,2,3), a hazard is not a risk if people are not exposed to a hazard at harmful levels. As with most ingredients, the dose makes the poison. If you’re ingesting, using, or coming into contact with a harmful phthalate, in large enough qualities an adverse health effect could result. However, known harmful phthalates are not permitted for use and are not found in new products.
 
At the time of this publication, research in male laboratory animals shows there can be adverse effects on their reproductive system development when exposed to phthalates at significant levels (1). However, research overwhelming shows that adult exposure to phthalates is well below the level of concern, even taking daily, accumulated use into consideration.
 
Therefore, the normal use of products containing phthalates is unlikely to pose a significant health risk (1,2,3).
 
There is an increased risk that infants, children, and other vulnerable populations could be exposed at higher than recommended levels and as a result, there are recommendations and ongoing research in place to help limit this exposure (1).

The good news.

As we continue to invest in research and learn more about these plasticizers we continue to see they are safe when used as intended. However, if new research shows these ingredients can cause harm, new regulations will be put into place to help protect our health.