HoldsUp

Shanna Swan

Dr. Shanna Swan is a researcher specializing in environmental health and epidemiology. Her published work focuses on the effects of environmental chemical exposures, such as phthalates and plastics, on fertility, pregnancy, and fetal development. Additionally, her research examines associations between prenatal maternal factors and exposures with childhood health outcomes, including autism spectrum disorder, ADHD, and asthma.

28 claims checked on air: 3 context 1 overstated 23 supported 1 unverified

What they said on air

4 citing their own research

0:04:35supportedhighMicroplastics Are Inside Your Body Right Now — Here's What T

The Carlsen study out of Denmark claimed that human sperm counts had declined by 50% over a 50-year period.

"The first thing they asked me to do was to look at a study out of Denmark that claimed that sperm count had declined 50% in 50 years. Yeah, that was the Carlsen paper." (said at 0:04:35)

The speaker accurately describes the landmark 1992 meta-analysis by Elisabeth Carlsen and colleagues from the University of Copenhagen (Denmark), published in the BMJ. The study reviewed 61 papers published between 1938 and 1991 (comprising 14,947 men) and reported that mean sperm concentration declined from 113 million/mL in 1940 to 66 million/mL in 1990 (a 42% drop in density), alongside a decrease in seminal volume from 3.40 mL to 2.75 mL, yielding an overall decline in total sperm count per ejaculate of over 50% across the 50-year span.

0:05:08supportedmoderateMicroplastics Are Inside Your Body Right Now — Here's What T

A reanalysis of 61 studies controlling for smoking, obesity rates, and sperm counting methods confirmed the 50-year sperm count decline trend.

"So, we looked at things that might explain it, like are there changes in smoking, changes in obesity rates, changes in how sperm count was measured, and so on and so forth. And we put all these variables into a large model—61 studies, we got all the data from—put it in a big model, ran the model, and then the big surprise was that that didn't change anything." (said at 0:05:08)

In 1997, Swan et al. published a reanalysis of the 61 studies originally analyzed by Carlsen et al. (1992), which had reported a ~50% worldwide decline in sperm density between 1938 and 1990. The reanalysis examined potential confounding and methodological variables—including specimen collection and counting methods, abstinence duration, age, fertility status, study location, and region—and found that controlling for these variables did not eliminate the significant downward trend in sperm density in the United States and Europe over the ~50-year period.

0:06:39supportedhighMicroplastics Are Inside Your Body Right Now — Here's What T

CDC NHANES biomonitoring data detected phthalates in nearly 100% of a representative sample of the US population.

"First of all, he said they were in everyone in the United States as far as they could determine at CDC because they had the NHANES study that sampled a representative sample of the US population, and you could see that it was positive. It was detected in the sample almost 100%." (said at 0:06:39)

Biomonitoring data from the CDC's National Health and Nutrition Examination Survey (NHANES), which examines a nationally representative sample of the U.S. population, shows ubiquitous exposure to phthalates. Analyses of NHANES samples demonstrate that major urinary phthalate metabolites are detected in nearly the entire sampled population (individual phthalate metabolites detected in 75% to 100% of participants, and at least one phthalate metabolite detected in 99–100% of individuals across demographic groups).

0:07:05supportedvery lowMicroplastics Are Inside Your Body Right Now — Here's What T

National Toxicology Program studies showed that prenatal exposure to phthalates causes male rodent offspring to develop less male-typical genital tracts, known as 'the phthalate syndrome.'

"he said that his colleagues in the National Toxicology Program had shown that when a pregnant rodent, rat or mouse, was exposed to phthalates, that their male offspring developed atypically. And what they did was they had a less male-typical genital tract, and we can talk about that some more. I'm sure we will. But they gave this the name 'the phthalate syndrome.'" (said at 0:07:05)

Extensive experimental toxicology research, notably led by researchers associated with the National Toxicology Program (NTP) and U.S. EPA, established that in utero exposure to specific phthalate esters impairs fetal Leydig cell testosterone and insulin-like peptide 3 (INSL3) production in male rodents. This suppression of androgen signaling disrupts normal male sexual differentiation, leading to a cluster of reproductive tract abnormalities (such as shortened anogenital distance, hypospadias, cryptorchidism, and underdeveloped reproductive organs) formally termed 'the phthalate syndrome.' Because this claim is based on animal models, the certainty of evidence is graded as very low under GRADE criteria.

0:08:36supportedlowMicroplastics Are Inside Your Body Right Now — Here's What T

Research by Dr. Shanna Swan demonstrated the occurrence of the phthalate syndrome in human male infants.

"but I did find the phthalate syndrome in humans." (said at 0:08:36)

Research led by Dr. Shanna Swan provided the first epidemiological evidence linking prenatal phthalate exposure to genital alterations in human male infants characteristic of the rodent 'phthalate syndrome'. In a landmark 2005 prospective study of mother-son pairs, higher maternal urinary concentrations of several phthalate metabolites (including MEP, MBP, MBzP, and MiBP) were significantly associated with shorter anogenital index (AGI), smaller penile volume, and incomplete testicular descent in male infants. These associations were subsequently replicated in larger multi-center cohorts (such as the TIDES study). Because these findings derive from observational cohort studies, the GRADE certainty is rated as low.

0:09:21supportedhighMicroplastics Are Inside Your Body Right Now — Here's What T

Phthalates are water-soluble compounds whose metabolites are excreted and measurable in human urine.

"And they're measurable in the human body pretty easily, which makes my work much easier, because they're water-soluble. And being water-soluble, they get into the urine as metabolites. They're metabolized, and so we measure metabolites of phthalates in the urine fairly easily." (said at 0:09:21)

The speaker's claim is supported by pharmacokinetic and biomonitoring literature. Diesters of phthalic acid undergo Phase I and Phase II biotransformation in the body to form monoesters and glucuronide conjugates. Phase II conjugation (e.g., glucuronidation) increases the water solubility of these compounds, facilitating their rapid excretion in human urine where their primary and secondary metabolites are easily measured as biomarkers of exposure (PMID: 14574443, PMID: 34520948, PMID: 35131323).

0:11:00supportedmoderateMicroplastics Are Inside Your Body Right Now — Here's What T

Phthalates are added to cosmetics and pesticides to increase barrier absorption and are used in fragranced products to retain scent and color.

"it helps the absorption through a skin barrier or other barriers of chemicals. And so, it's added to hand lotion, and it's also added to pesticides... And another important thing it does: it helps retain scent and color. So, it's added to makeup—lipstick and products you put on your skin—as well as fragrance." (said at 0:11:00)

Phthalates (most notably diethyl phthalate [DEP] and dibutyl phthalate [DBP]) are widely documented functional additives in cosmetics, fragranced personal care items, and agrochemical formulations. In cosmetic and fragrance formulations, low-molecular-weight phthalates function as solvents and fragrance fixatives that retard evaporation to prolong scent retention, as well as plasticizers and permeation aids in leave-on products such as lotions, nail polishes, and creams.

0:12:00supportedhighMicroplastics Are Inside Your Body Right Now — Here's What T

The Consumer Product Safety Improvement Act of 2008 banned phthalates from children's toys in the United States.

"Finally, they decided that they would ban it in children's toys—that's the rubber ducky... The Consumer Product Safety Improvement Act of 2008 did not protect pregnant women." (said at 0:12:00)

Section 108 of the Consumer Product Safety Improvement Act (CPSIA) of 2008 enacted federal restrictions banning specific phthalates in concentrations greater than 0.1% from children's toys and child care articles in the United States. The law was specifically written to cover products intended for children rather than adult consumer goods or interventions tailored to pregnant women.

0:16:54supportedmoderateMicroplastics Are Inside Your Body Right Now — Here's What T

Phthalates act as anti-androgenic chemicals that lower androgen/testosterone levels.

"Phthalates are a class of several chemicals which have a similar structure and similar effect. And by the way, the phthalates are androgen-lowering. They're anti-androgens, okay?" (said at 0:16:54)

Phthalates are well-established environmental endocrine disruptors that exert anti-androgenic effects. Mechanistic and animal studies demonstrate that phthalate exposure impairs testosterone biosynthesis in Leydig cells by suppressing the expression of key steroidogenic enzymes. Systematic reviews of human epidemiological evidence also show associations between exposure to major phthalates (such as DEHP, DBP, and DINP) and reduced testosterone levels as well as other anti-androgenic reproductive outcomes.

0:17:20needs contextlowtheir own paperMicroplastics Are Inside Your Body Right Now — Here's What T

Women with higher urinary levels of phthalates reported lower sexual satisfaction and lower sexual frequency.

"in one of our studies, we asked women about their sexual satisfaction and frequency, and women who had higher levels of phthalates had lower satisfaction and lower frequency." (said at 0:17:20)

The speaker is referring to research from their group (Barrett, Swan et al., 2014, in the Study for Future Families cohort, n = 360). The study evaluated self-reported sexual dysfunction in premenopausal women and found that women in the highest quartile of urinary di-2-ethylhexyl phthalate (DEHP) metabolites had significantly higher odds of reporting frequent lack of sexual interest/desire (adjusted OR ~2.6), though other dimensions like vaginal dryness showed no significant association. While the finding specifically demonstrated reduced sexual desire/interest rather than explicitly measuring sexual satisfaction and frequency as separate validated endpoints, the core observation of endocrine-disrupting phthalates correlating with impaired female sexual function is consistent with their cohort's published findings.

0:18:59supportedmoderateMicroplastics Are Inside Your Body Right Now — Here's What T

PFAS chemicals interfere with human antibody responses to vaccinations.

"they're conveying harm because they interfere with your antibody response to vaccines, for example." (said at 0:18:59)

Prospective human cohort studies and booster vaccination trials show that exposure to per- and polyfluoroalkyl substances (PFAS) is inversely associated with antibody responses to vaccines, including tetanus, diphtheria, and hepatitis vaccines. Higher serum concentrations of PFAS during early childhood, adolescence, and adulthood correlate with significant reductions in post-vaccination specific serum antibody titers.

0:24:07supportedmoderateMicroplastics Are Inside Your Body Right Now — Here's What T

Microplastics have been detected and measured in human blood, placentas, seminal fluid, and breast milk.

"People have measured them in their blood. They've been measured in placentas. They've been measured in seminal fluid. They've been measured in breast milk." (said at 0:24:07)

Multiple human biomonitoring studies and systematic reviews confirm that microplastics have been detected and quantified across various human biological fluids and tissues, specifically including whole blood, placental tissue, semen/seminal fluid, and breast milk.

0:37:59supportedmoderateMicroplastics Are Inside Your Body Right Now — Here's What T

Human spermatogenesis takes approximately 70 days.

"And why three months? Well, it's because it takes 70 days to make a sperm." (said at 0:37:59)

Human spermatogenesis is classically estimated to take approximately 64 to 74 days. In classic kinetic studies using intratesticular injections of tritiated thymidine, the duration of testicular spermatogenesis alone was calculated to take approximately 64 days across roughly four cycles of the seminiferous epithelium. When factoring in the additional 10 to 14 days required for transit through the epididymis to produce mature spermatozoa in the ejaculate, the total timeline from spermatogonial differentiation to ejaculation is widely recognized in physiology as taking approximately 70 to 74 days (roughly 2.5 to 3 months).

0:39:14overstatedvery lowtheir own paperMicroplastics Are Inside Your Body Right Now — Here's What T

A 3-month intervention reducing plastic chemical exposures lowered urinary metabolite levels to non-detectable levels and improved semen parameters in infertile couples.

"To non-detect from quite high levels, and that's shown in the film. And we also published a paper uh containing a scientific paper in a peer-reviewed journal with these data. And um so their levels went down... Yes. Their semen parameters changed." (said at 0:39:14)

The peer-reviewed study associated with the film "The Plastic Detox" was published as an uncontrolled pilot study in five subfertile couples (PMID 41893525). While the authors reported directional reductions in urinary plastic biomarkers (such as bisphenol A, MBP, and MBzP) and descriptive upward trends in semen parameters over the 3-month intervention, claiming that levels fell to non-detectable levels overstates the reported findings (which were directional reductions). Furthermore, because the study was a tiny uncontrolled pilot feasibility study, the observed changes cannot prove efficacy.

0:39:40needs contextvery lowtheir own paperMicroplastics Are Inside Your Body Right Now — Here's What T

In a 3-month plastic detox intervention pilot study of infertile couples, three out of five couples achieved pregnancy.

"And then we have um several pregnancies as well. Um and um three three of the five... These were absolutely couples that had tried for more than a year, some as much as 10 years to get pregnant." (said at 0:39:40)

The claim refers to 'The Plastic Detox' study, a 3-month uncontrolled feasibility pilot study of 5 idiopathically infertile couples undergoing a lifestyle intervention to reduce endocrine-disrupting chemical exposure. The published trial actually reported that four (rather than three) out of the five couples achieved pregnancy and live birth during follow-up. However, because this was a tiny feasibility study (N=5 couples) without a control group, the study authors emphasize that pregnancy outcomes are strictly descriptive and cannot prove that the intervention caused or contributed to the pregnancies.

0:41:54needs contextmoderateMicroplastics Are Inside Your Body Right Now — Here's What T

Phthalates lower testosterone levels, while bisphenols raise estrogen levels.

"One of them, the phthalates, makes plastic soft and flexible and it lowers testosterone, and the other one makes plastic hard, firm, hard and raises estrogen." (said at 0:41:54)

The speaker's summary broadly reflects the classic endocrine-disrupting profiles of these plasticizers, though with a nuance regarding mechanism: phthalates are well-documented antiandrogens that suppress steroidogenesis and correlate with lower testosterone levels, whereas bisphenols (such as bisphenol A) primarily act as xenoestrogens by binding and activating estrogen receptors (mimicking estrogenic activity) rather than simply increasing circulating endogenous estrogen concentrations in every context. Systematic reviews and meta-analyses demonstrate that phthalate exposure (notably DEHP) is inversely associated with total testosterone and androgen indices in men, while bisphenols act as estrogen receptor agonists and disrupt hypothalamic-pituitary-gonadal signaling.

0:42:20supportedmoderateMicroplastics Are Inside Your Body Right Now — Here's What T

Touching thermal paper receipts, particularly when wearing hand cream, causes significant absorption of bisphenols into the body.

"Because you when you touch that—we've done a study which shows you touch that, particularly if you have hand cream on, you're getting a lot of bisphenols into your body, and every cashier gets a lot." (said at 0:42:20)

Published experimental and occupational exposure studies confirm that handling thermal paper receipts transfers substantial amounts of free bisphenols (such as bisphenol A / BPA) onto the skin. The presence of dermal penetration enhancers, hand creams, lotions, or sanitizers markedly increases both the transfer to skin and systemic absorption into blood and urine, bypasses first-pass hepatic metabolism, and leads to heightened exposure among cashiers who repeatedly handle receipt paper.

0:43:26supportedmoderateMicroplastics Are Inside Your Body Right Now — Here's What T

Metal food cans are lined with bisphenol unless explicitly specified otherwise by the manufacturer.

"It lines all your tin cans unless there's a specific effort by the company to say they are not using bisphenol in their linings" (said at 0:43:26)

Bisphenol A (BPA)-based epoxy resins have traditionally served as the standard protective coating lining metal food and beverage cans. Literature on food packaging and regulatory transitions confirms that non-bisphenol alternatives (referred to as BPA-free or BPA-Non-Intent / BPA-NI chemistries) require deliberate reformulation and specific industry compliance effort to replace standard BPA-based epoxy linings.

0:45:09supportedhighMicroplastics Are Inside Your Body Right Now — Here's What T

Thalidomide taken during pregnancy caused children to be born with limb reduction defects.

"One of them was thalidomide that caused children to be born without arms and legs" (said at 0:45:09)

Thalidomide exposure during early pregnancy is well documented as a potent teratogen that causes severe limb reduction defects, notably phocomelia (severe shortening or absence of long bones) and amelia (complete absence of limbs), alongside other congenital abnormalities.

0:45:09supportedhighMicroplastics Are Inside Your Body Right Now — Here's What T

Diethylstilbestrol (DES) taken during pregnancy caused cancer in children born to those women.

"and one was DES, diethylstilbestrol, which caused cancer in the children born to women who took it during pregnancy." (said at 0:45:09)

The statement is supported by decades of epidemiological and clinical research. Diethylstilbestrol (DES) was prescribed to pregnant women primarily between 1938 and 1971. In utero exposure was definitively shown to cause rare vaginal and cervical clear cell adenocarcinoma (CCA) in female offspring, along with other reproductive tract abnormalities and an elevated risk of subsequent breast cancer.

0:45:30unverifiedvery lowMicroplastics Are Inside Your Body Right Now — Here's What T

The FDA removed DES from the market within six months of the publication of Herbst's paper demonstrating its link to cancer.

"FDA responded immediately to the DES information and took DES off the market within six months of the publication of Herbst's paper showing that causes cancer." (said at 0:45:30)

No published record matching the claim that the FDA took diethylstilbestrol (DES) off the market within six months of the publication of Herbst's paper was located; this does not prove the claim false.

0:46:46supportedhighMicroplastics Are Inside Your Body Right Now — Here's What T

Under the European Union's REACH regulation, a new chemical product cannot be placed in commerce until it is tested for safety.

"REACH is a program that was um put in place by the EU... And it has the really important um caveat, which is um if you want to bring in a new product and put it in commerce, you can't do that until it's tested for safety first." (said at 0:46:46)

Under the European Union's REACH regulation (Regulation (EC) No 1907/2006 concerning the Registration, Evaluation, Authorisation and Restriction of Chemicals), manufacturers and importers are required to demonstrate the safety of chemical substances by submitting hazard and safety dossiers prior to placing them on the EU market. This foundational rule is known in EU law and policy analysis as the 'no data, no market' principle, which places the burden of proof on industry to identify intrinsic chemical properties and safe handling conditions before commercial distribution.

0:46:57supportedhighMicroplastics Are Inside Your Body Right Now — Here's What T

Microwaving food in plastic containers causes plasticizers to migrate out of the plastic matrix and into the food.

"Because what happens is that the plasticizers which are added to the plastic are not tightly bound to that matrix, and so when you heat it, the particles get active, they hop out of the plastic, they hop into your food, they get into your body." (said at 0:46:57)

The claim is supported. Plasticizers (such as phthalate esters) are added to polymers as non-covalently bound additives to increase flexibility and workability. Because they are not chemically bound to the polymer matrix, heating (including microwave heating) increases molecular mobility and accelerates the migration (leaching) of plasticizers from plastic food contact materials into food or food simulants, leading to dietary exposure.

0:49:33supportedmoderatetheir own paperMicroplastics Are Inside Your Body Right Now — Here's What T

Pregnant women who report using fragranced products have higher measured bodily levels of phthalates.

"We asked them what they used in the last 24 hours, and then we asked, was it fragranced? And when the women reported use of fragranced products, their levels of several chemicals were higher, particularly the phthalates in their bodies." (said at 0:49:33)

Observational cohort studies in pregnant and postpartum women consistently demonstrate that self-reported use of personal care products (such as perfumes and fragranced products) within the previous 24 to 48 hours is associated with higher urinary concentrations of phthalate metabolites, most notably monoethyl phthalate (MEP).

1:02:37supportedhighMicroplastics Are Inside Your Body Right Now — Here's What T

Products marketed as BPA-free often substitute BPA with other bisphenol analogs such as BPF and BPS.

"Probably if they took the trouble to put BPA-free on the label, they've already put in an alternative like BPF and BPS." (said at 1:02:37)

Extensive literature and systematic reviews confirm that when bisphenol A (BPA) was phased out of consumer plastics, resins, and thermal paper due to health regulations and consumer pressure, manufacturers widely substituted BPA with structural analogs—predominantly bisphenol S (BPS) and bisphenol F (BPF)—while labeling products as 'BPA-free'.

1:03:08supportedhighMicroplastics Are Inside Your Body Right Now — Here's What T

Only a very small percentage of plastic waste placed in recycling bins is actually recycled.

"Well, we all put our plastic in the recycle box back then, right? Me too. But a very small percent of that is actually recycled" (said at 1:03:08)

Global assessments of plastic life cycles and waste management consistently indicate that only a small fraction of plastic waste is successfully recycled. Cumulative global estimates and waste tracking studies show that less than 10% to 16% of all plastic waste generated is recycled, with the overwhelming majority ending up in landfills, incinerated, or discarded into the environment. Furthermore, studies tracking materials placed into municipal recycling streams have documented significant losses due to sorting limitations, lack of viable end-markets, contamination, and the inadequate handling of exported plastic waste.

1:04:09supportedhighMicroplastics Are Inside Your Body Right Now — Here's What T

Heating food or liquids in plastic results in greater chemical exposure than merely storing them in plastic.

"Oh, heating in plastic, no question. Heating." (said at 1:04:09)

Extensive physical chemistry and food safety literature confirms that heating food or liquids in plastic significantly increases chemical migration and leaching compared to low-temperature or room-temperature storage. Systematic reviews and standardized experimental migration assays show that elevated temperatures (such as during microwaving, boiling, or hot filling) accelerate the diffusion kinetics of plasticizers (e.g., phthalates), monomers (e.g., bisphenols), synthetic phenolic antioxidants, and non-intentionally added substances into food and food simulants.

1:05:11supportedmoderateMicroplastics Are Inside Your Body Right Now — Here's What T

PFAS chemicals are added to stain- and water-resistant fabrics and clothing, including flight attendant uniforms, firefighter gear, sportswear, and children's school uniforms.

"And it's particularly concerning if you use clothing that has barriers, like flight attendants, firefighters, sportswear, children's school uniforms. PFAS was the class of chemical I'm talking about that's added to all of these" (said at 1:05:11)

Published analytical chemistry and environmental exposure studies confirm that per- and polyfluoroalkyl substances (PFAS) are applied to textiles and apparel requiring durable water, oil, or stain resistance. This includes firefighter turnout gear (where PFAS are used in moisture barriers and outer shells), outdoor apparel and sportswear, and stain-resistant children's school uniforms.

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