Tag: phthalates

Airborne Levels of Chemicals Released by Plastics Shock Researchers

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A new study documents how people in California are chronically being exposed to toxic airborne chemicals called plasticisers, including one banned from children’s items and beauty products. 

Plasticizers are chemical compounds that make materials more flexible. They are used in a wide variety of products ranging from lunchboxes and shower curtains to garden hoses and upholstery. 

“It’s not just for drinking straws and grocery bags,” said David Volz, environmental sciences professor at UC Riverside, and corresponding author of the study published in the journal Environmental Research

Previous California monitoring programs focused on plasticisers called ortho-phthalates, some of which were phased out of manufacturing processes due to health and environmental concerns. Less research has focused on the health effects of their replacements, called non-ortho-phthalates. This study revealed the presence of both types of plasticisers in the air throughout Southern California.

“The levels of these compounds are through the roof,” Volz said. “We weren’t expecting that. As a result, we felt it was important for people to learn about this study.”

The National Institute of Environmental Health Sciences also wants to increase the visibility of this study, one of only a few to document the phthalates’ presence in the air of urban environments. The institute’s monthly newsletter, Environmental Factor, highlights the study in their October 2024 issue.  

The researchers tracked two groups of UCR undergraduate students commuting from different parts of Southern California. Both groups wore silicone wristbands designed to collect data on chemical exposures in the air. 

The first group wore their wristbands for five days in 2019, and the second group wore two different wristbands for five days each in 2020. Both groups wore the bands continuously, all day, as they went about their activities. At the end of the data collection period, the researchers chopped the wristbands into pieces, then analysed the chemicals they contained. 

In a previous paper, the team focused on TDCIPP, a flame-retardant and known carcinogen, picked up in the wristbands. They saw that the longer a student’s commute, the higher their exposure to TDCIPP. 

Unlike TDCIPP, which most likely migrates out of commuters’ car seats into dust, the team cannot pinpoint the origin of the plasticisers. Because they are airborne, rather than bound to dust, the wristbands could have picked them up anywhere, even outside the students’ cars.

For every gram of chopped-up wristband, the team found between 100 000 and 1 million nanograms of three phthalates, DiNP, DEHP, and DEHT. Ten total plasticizers were measured, but the levels of these three stood out.

Both DiNP and DEHP are included on California’s Proposition 65 list, which contains chemicals known to cause cancer, birth defects, or other reproductive harm. DEHT was introduced as an alternative, but its effects on human health have not been well studied. 

This study suggests that introducing DEHT also has not done much to reduce the public’s level of exposure to DiNP or DEHP. Levels of all three chemicals found by Volz and his team were similar to those found by researchers in unrelated studies conducted on the East Coast. 

Despite differences in climate, the air on both coasts is likely carrying similar levels of phthalates.

“No matter who you are, or where you are, your daily level of exposure to these plasticizer chemicals is high and persistent,” Volz said. “They are ubiquitous.”

To Volz, studies like this one amplify the need to find alternatives to plastic. As plastics degrade, these compounds and others like them are leaching out into the environment and into the body. 

“The only way to decrease the concentration of plasticisers in the air is to decrease our production and consumption of materials containing plasticisers,” he said. 

Source: University of California – Riverside

Phthalates in Everyday Products do Cause Uterine Fibroids

Photo by Sora Shimazaki on Pexels

For the first time, a study published Proceedings of the National Academy of Sciences (PNAS) has shown a causal association between environmental phthalates and the increased growth of uterine fibroids, the most common tumours among women.

Manufacturers use environmental phthalates in numerous industrial and consumer products, and they’ve also been detected in medical supplies and food. Although they are known to be toxic, they are currently unbanned in the US.

“These toxic pollutants are everywhere, including food packaging, hair and makeup products, and more, and their usage is not banned,” said corresponding study author Dr Serdar Bulun at Northwestern University. “These are more than simply environmental pollutants. They can cause specific harm to human tissues.”

Up to 80% of all women may develop a fibroid tumour during their lifetime, Bulun said. One-quarter of these women become symptomatic with excessive and uncontrolled uterine bleeding, anaemia, miscarriages, infertility and large abdominal tumours necessitating technically difficult surgeries.

The new study found women with a high exposure to certain phthalates such as DEHP (used as a plasticiser to increase the durability of products such as shower curtains, car upholstery, lunchboxes, shoes and more) and its metabolites have a high risk for having a symptomatic fibroid.

Prior epidemiological studies have consistently indicated an association between phthalate exposure and uterine fibroid growth, but this study explains the mechanisms behind that link. The scientists discovered exposure to DEHP may activate a hormonal pathway that activates an environmentally responsive receptor (AHR) to bind to DNA and cause increased growth of fibroid tumors.

“Interestingly, AHR was cloned in the early ’90s as the receptor for dioxin, the key toxin in the agent orange,” Bulun said. “The use of agent orange during the Vietnam war caused significant reproductive abnormalities in the exposed populations; and dioxin and AHR were thought to be responsible for this.”

This new study, Bulun said, provides further evidence to support these theories.

Source: Northwestern University

Maternal Phthalates Exposure Increases Preterm Birth Risk

pregnant woman holding her belly
Source: Anna Hecker on Unsplash

A National Institutes of Health study has found that pregnant women who were exposed to multiple phthalates during pregnancy had an increased risk of preterm birth. The most significant correlation was for a phthalate most commonly used in nail polish and cosmetics.

Used in a great variety of products such as cosmetics and food packaging, phthalates are endocrine-disrupting chemicals that are known to have a wide range of health effects on humans. This especially true of children, due to their impact on the developmental system, as well as the reproductive system.

Researchers analysed data from more than 6000 pregnant women in the US, and found that women with higher concentrations of several phthalate metabolites in their urine had increased risks of preterm birth.

“Having a preterm birth can be dangerous for both baby and mom, so it is important to identify risk factors that could prevent it,” said epidemiologist Kelly Ferguson, PhD, the senior author on the study published in JAMA Pediatrics.

Data from 16 US studies that included individual participant data on prenatal urinary phthalate metabolites (representing exposure to phthalates) as well as the timing of delivery. Researchers analysed data from a total of 6045 pregnant women who delivered between 1983-2018, 9% of whom delivered preterm. Phthalate metabolites were detected in more than 96% of urine samples.

Exposure to four of the 11 phthalates found in the pregnant women was associated with a 14–16% greater probability of having a preterm birth. The most consistent findings were for exposure to a phthalate that is used commonly in personal care products like nail polish and cosmetics.

Using statistical models to simulate interventions that reduce phthalate exposures, the researchers found that reducing the mixture of phthalate metabolite levels by 50% could prevent preterm births by 12% on average. Interventions targeting behaviours, such as trying to select phthalate-free personal care products (if listed on label), voluntary actions from companies to reduce phthalates in their products, or changes in standards and regulations could contribute to exposure reduction and protect pregnancies.

“It is difficult for people to completely eliminate exposure to these chemicals in everyday life, but our results show that even small reductions within a large population could have positive impacts on both mothers and their children,” said Barrett Welch, PhD, first author on the study.

Eating fresh, home-cooked food, avoiding processed food that comes in plastic containers or wrapping, and selecting fragrance-free products or those labeled ‘phthalate-free’, are examples of things people can do that may reduce their exposures. Changes to the amount and types of products that contain phthalates could also reduce exposures.

The researchers are undertaking further studies to better understand the mechanisms behind how phthalates affect pregnancy and to find ways for mothers to reduce their exposures.

Source: National Institutes of Health

PFAS and Phthalates Linked to Reduced Bone Density in Teen Boys

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Per- and polyfluoroalkyl substances (PFAS) and phthalates (two types of endocrine-disrupting chemicals) may be associated with lower areal bone mineral density (aBMD) in teenage boys, according to a new study published in the Journal of Clinical Endocrinology and Metabolism.

Endocrine disrupting chemicals (EDCs) and potential EDCs are mostly man-made found in various materials. By interfering with the body’s endocrine system, endocrine disruptors produce adverse developmental, reproductive, neurological, and immune effects in humans, abnormal growth patterns and neurodevelopmental delays in children. These include per- and polyfluoroalkyl substances (PFAS) are used in non-stick pots and pans, clothing and food packaging, and are increasingly being found in US water supplies. Phthalates are used in medical devices, personal care products, food processing and children’s toys.

“Adolescence is an important time when our bodies build up bone. Almost all US children and adolescents are exposed to PFAS and phthalates, but few studies have looked at how these chemicals could be impacting our bone health,” said Abby F. Fleisch, MD, MPH, of the Maine Medical Center Research Institute and Maine Medical Center. “Our research found an association between certain PFAS and phthalates and reduced bone mineral density in adolescent males. Because bone accrual primarily occurs during adolescence, if replicated, this finding may have implications for lifelong bone health.”

The researchers accessed data on urine and blood samples from 453 boys and 395 girls from the National Health and Nutrition Examination Survey (NHANES). Participants were on average 15.1 years old, and found that higher levels of PFAS and phthalates may be associated with lower aBMD in adolescent males. The same effect was not found in girls; rather a slight increase in aBMD was observed for certain PFAS and phthalates.

The researchers noted that bone mineral density tracks across a lifetime, so if the same results are seen in longitudinal cohorts, this finding may have implications for lifelong skeletal health.

Source: The Endocrine Society