Plastics are everywhere in modern life, but they come with hidden health risks that demand our attention.
Specifically, chemicals called phthalates used to soften plastics can pose significant risks to human health, especially for vulnerable groups like children.
Here are key facts you need to know about phthalates:
- Phthalates are added to plastics like PVC to make them soft and flexible. They are found in many products we use every day.
- Phthalates aren’t chemically bound to plastics so they easily leach out into food, dust, air, and water. This means we are constantly exposed.
- Phthalates are endocrine disruptors that interfere with natural hormone functions in the body. They have been linked to reproductive, developmental, and neurological harm.
- Fetuses, infants, and children are most vulnerable to phthalates due to critical windows of development. Even low doses can impact growth and function.
- While some phthalates like DEHP are restricted in children’s products in the US and EU, others remain widely used with potential for harm.
Source: Healthcare (Basel) 2021
Read on to learn more about where phthalates lurk, how exposure happens, and what health risks these concerning chemicals present.
Where Are Phthalates Found?
Phthalates are used in everything from food packaging and personal care products to building materials and medical devices.
Two of the most widely used phthalates are DEHP and DBP.
DEHP can be found in:
- PVC pipes, flooring, and cables
- Wall coverings and tablecloths
- Shower curtains
- Garden hoses
- Toys and childcare products
- Medical tubing and blood storage bags
DBP is used in:
- Adhesives, inks, and paints
- Nail polish
- Hair spray and aftershave
- Food packaging
Other phthalates like DEP and DiNP are commonly found in fragrances, cosmetics, insect repellent, and oral medications.
Clearly, phthalates are ubiquitous in modern products we interact with every day.
Widespread Phthalates Exposure via Leaching
Unlike chemicals that are tightly bound to plastics, phthalates are only weakly linked.
This means they easily leach out of products over time and end up in the environment.
Phthalates can enter our bodies through:
Ingestion
- Eating foods that picked up phthalates during production, processing, or packaging
- Drinking water contaminated with phthalates leached from PVC pipes
- Swallowing household dust containing phthalates
Inhalation
- Breathing indoor air contaminated with phthalate off-gassing from building materials and products
- Car exhaust containing phthalates in the outdoor air
Skin contact
- Using personal care products that contain phthalates
- Handling toys, medical devices, and other products containing phthalates
- Absorption from a polluted environment
Once phthalates enter our bodies, they are quickly metabolized and excreted in urine and feces.
But constant exposure from multiple sources leads to bioaccumulation.
Studies consistently detect phthalates and their breakdown products in a majority of people tested.
Vulnerable Populations: Higher Health Risks from Phthalate Exposure
While phthalates pose risks to adults, developing children are uniquely vulnerable.
Studies show childhood exposure is associated with:
- Impaired reproductive development
- Delayed brain and motor development
- Learning and attention deficits
- Increased risk for obesity and diabetes
The health impacts later in life are linked to early exposure because the endocrine system and organs are rapidly developing.
Interference with natural hormones during critical windows of growth can have permanent consequences.
Pregnant women and fetuses are also highly susceptible to phthalate harms.
Some phthalates can cross the placenta.
Prenatal exposure has been tied to adverse outcomes including preterm birth, lower birth weight, and birth defects.
Finally, infants and toddlers are prone to higher exposure levels due to behaviors like mouthing toys, crawling on floors, and hand-to-mouth contact.
Their smaller size compared to the dose also increases potential harm.
Mechanisms of Hormone Disruption from Phthalates
The most concerning health effects of phthalates are tied to their role as endocrine disrupting chemicals.
The endocrine system regulates key processes in the body through hormones.
Phthalates interfere with natural hormone signaling pathways.
Specifically, studies suggest phthalates may:
- Reduce testosterone and thyroid hormone levels
- Mimic or block estrogen
- Disrupt glucocorticoids like cortisol
- Alter receptors for androgen and thyroid hormones
The problems arise when these hormones are thrown off balance during fetal development and other critical life stages.
The interference can have cascading effects on metabolism, reproduction, brain function, immunity, and more.
Research also indicates phthalates may influence gene expression and trigger inflammation, oxidative stress, and cell death pathways at certain doses.
The complex mechanisms are still being unraveled.
Reproductive Harm in Males and Females Exposed to Phthalates
Human studies consistently link certain phthalates like DEHP and DBP to adverse effects on the reproductive system in both males and females.
In males, developmental exposure has been tied to:
- Impaired sperm quality and reduced fertility
- Malformations of the penis and undescended testes
- Lower testosterone levels
- Higher rates of testicular cancer
In females, prenatal exposure to phthalates has been associated with:
- Early onset of puberty
- Premature breast development
- Endometriosis and uterine fibroids
- Polycystic ovarian syndrome (PCOS)
Phthalates are thought to contribute to these reproductive issues by reducing testosterone production in males and mimicking/blocking estrogen in females.
More research is needed, but avoiding exposure during critical periods of growth is prudent.
Link to Neurodevelopmental Harm from Phthalates
There is mounting evidence that phthalate exposure affects neurological development and function.
Childhood exposure has been associated with:
- Lower IQ and impaired motor skills
- Learning disabilities and ADHD
- Poor memory and problems with executive function
- Increased behavioral issues and aggression
The prefrontal cortex and areas involved in learning, attention, and social behaviors seem particularly vulnerable to phthalate disruption based on studies in animals.
More research is needed, but these chemicals are emerging as potential contributors to neurodevelopmental disorders.
Phthalates Linked to Obesity, Diabetes, and Thyroid Disruption
Phthalates are also implicated as obesogens and contributors to diabetes based on human epidemiological studies.
Potential mechanisms include:
- Disruption of metabolic hormones like thyroid, growth hormones, and glucocorticoids
- Reprogramming genes involved in fat cell development and glucose metabolism
- Inflammation which alters insulin signaling
Higher exposures in childhood are associated with increased body fat, insulin resistance, and other metabolic issues later in life.
There are also links between phthalates and thyroid dysfunction which controls metabolism.
Asthma & Allergy Risks of Phthalates
A few large-scale studies have connected phthalate exposure with higher rates of asthma, allergies, and airway inflammation.
Children with higher exposures tend to have more pulmonary issues.
While more research is needed, potential mechanisms linking phthalates to respiratory harm include:
- Oxidative stress causing airway inflammation
- Enhanced immune system stimulation and overproduction of antibodies/histamine
- Endocrine disruption altering stress hormones
Overall, phthalates should be considered a potential contributor to asthma and allergy development, especially in genetically susceptible children.
Risks vs. Benefits of Phthalate Use
While phthalates clearly provide functionality like flexibility to plastics, the ubiquity of exposure and potential health harms demand greater restriction and regulation.
Alternatives exist, but have been slow to replace phthalates in many applications.
For high-risk products like food packaging, medical devices, flooring, and other items with direct human exposure, phasing out harmful phthalates is necessary and feasible.
With increasing awareness and advocacy, policy and industry practices are beginning to shift.
But for now, individuals and families, especially those with young children, should take steps to reduce exposure risks:
- Choose fragrance-free personal care and cleaning products
- Avoid plastics numbered 3, 6, and 7
- Use glass, stainless steel, wood, or ceramic containers when possible
- Don’t microwave food in plastic
- Check labels and avoid toys/products containing phthalates
- Ventilate and clean homes frequently
While individual action is limited against such widespread pollutants, small choices can reduce your family’s exposure.
Putting pressure on companies and policymakers is also critical to continue the progress in restricting phthalates in products we use every day.
References
- Study: Phthalates and their impacts on human health
- Authors: Wang & Qian (2021)
