Dr Leonardo Trasande
Paediatrician, NYU Professor and author of Sicker Fatter Poorer on the true cost of endocrine disrupting chemicals to human health.
Dr Leonardo Trasande is Professor of Paediatrics, Environmental Medicine and Population Health at NYU Langone Health and Director of the Division of Environmental Paediatrics. He is internationally recognised for his research into the economic and health costs of endocrine disrupting chemical exposure, leading studies that documented $340 billion in annual disease costs in the US and €163 billion in Europe attributable to chemical exposure. His 2019 book Sicker Fatter Poorer brought this research to a mainstream audience for the first time. He represents the Endocrine Society at the Global Plastics Treaty negotiations and has contributed to the World Health Organization and UNEP reports on endocrine disrupting chemicals. He trained at Harvard and completed a legislative fellowship in the office of Senator Hillary Rodham Clinton. He has said that endocrine disrupting chemicals are one of the biggest global health threats of our time and that 2% of the population know about it while 99% are affected by it.
Watch the Talk
In this TEDx talk delivered at the Great Pacific Garbage Patch in December 2025, Dr Trasande covers how plastics and the chemicals they contain cause harm from before birth through to old age, and what the economic and health costs of inaction look like. One of the most recent and comprehensive public talks he has given on this subject.
Key Points from His Research
Trasande's research has quantified what most policy makers ignore. His studies found that endocrine disrupting chemical exposure costs the US $340 billion annually and Europe €163 billion in disease burden. More recently his team documented $249 billion per year in US disease costs attributable specifically to chemicals in plastics. These figures come from calculating the economic cost of conditions directly linked to chemical exposure including infertility, obesity, diabetes, learning disabilities and certain cancers.
Trasande identifies five categories of endocrine disrupting chemicals that carry the strongest evidence for human health harm: bisphenols (BPA and its replacements), phthalates, pesticides, flame retardants and PFAS. These are not obscure industrial chemicals. They are present in food packaging, non-stick cookware, children's products, cleaning products, clothing and personal care products used in virtually every household every single day.
As a paediatrician Trasande focuses particularly on the effects of chemical exposure during development. He notes that children have higher surface-area-to-body-weight ratios than adults, breathe more air per kilogram of body weight, eat more food per kilogram and have developing organ systems that are more sensitive to chemical interference. The window of fetal development and early childhood is the period of greatest vulnerability and the period in which chemical damage is most likely to have lasting consequences.
Trasande has researched what he calls obesogens, endocrine disrupting chemicals that interfere with the body's metabolism and fat storage mechanisms. His research suggests that chemical exposure is a contributing factor to the global obesity epidemic that cannot be explained by diet and exercise alone. BPA exposure in particular has been associated with disrupted metabolic signalling in multiple studies.
Unlike some researchers in this field, Trasande is explicitly empowering in his approach. He argues that while systemic regulatory change is essential, individual choices about what we eat, what we cook with and what we put on our bodies make a measurable and meaningful difference to our personal chemical body burden. Eating organic reduces pesticide exposure. Switching to glass storage reduces bisphenol exposure. Choosing PFAS-free cookware reduces PFAS intake from food. Small changes, consistently applied, add up.
What He Covers in This Talk
Trasande opens with an admission that healthcare itself is part of the plastic problem. US hospitals generate 14,000 tons of waste annually, 20% of which is plastic, much of it non-essential. Medical schools still give students between one and four hours of environmental health training across their entire education less time than a single open heart surgery. The profession has been largely asleep to the issue.
He then challenges the foundational assumption that has governed toxicology for centuries the idea that only the dose makes the poison. For endocrine disrupting chemicals, this principle breaks down completely. These chemicals operate at the same vanishingly small concentrations as the hormones they mimic and disrupt. The dose that causes harm is not large. It is the dose that is already present in our bodies from everyday exposure.
Plastic hacks our hormones the concert masters of human function. These chemicals operate at the same levels as grains of sand in a desert or salt in an Olympic size swimming pool. And that is exactly the level at which hormones normally operate.
Dr Leonardo Trasande, TEDx Great Pacific Garbage Patch, December 2025
Trasande then walks through the four chemical categories with the strongest evidence for harm. Flame retardants, added to plastic devices to prevent them igniting. Phthalates, used to soften PVC plastic in food packaging and cosmetics. Bisphenols, used in aluminium can linings and thermal paper receipts. And PFAS, the forever chemicals used in non-stick cookware and water resistant clothing. None of these are obscure industrial compounds. They are in products handled and consumed by virtually every household every day.
The health impacts span the entire human lifespan. Chemical exposure during fetal development reduces birth weight and programs babies for an adverse metabolic profile for the rest of their lives obesity, diabetes and heart disease. Thyroid disruption during pregnancy, even within the clinically normal range, causes measurable shrinkage of the developing brain. The resulting cognitive deficits, attention disorders and autism spectrum conditions are permanent. 50,000 Americans between the ages of 55 and 64 die each year of early heart disease attributable to phthalate exposure alone.
The annual cost of diseases attributable to chemicals in plastics in the US alone. That is 1.2% of gross domestic product and covers only the plastic-specific chemicals, just one category of the 16,000 chemicals used in plastic materials. Science currently knows nothing meaningful about 10,000 of those 16,000 compounds.
Scaling to a global level, phthalate exposure alone is responsible for an estimated 350,000 deaths annually, 70% of them in the Asia-Pacific region. The social cost of those deaths runs between $510 billion and $3.74 trillion. The entire global revenue of the plastics industry is $500 to $700 billion a year. By Trasande's calculation, the industry is already a net economic loser based on a single disease endpoint from a single chemical category, before microplastics, nano plastics or the other 15,000 compounds are factored in at all.
He closes with a call to action directed at healthcare specifically, but the principle extends to everyone. Medicine led the removal of mercury from hospital incinerators. It led the campaign against lead exposure in children. It can lead again. The National Academy of Sciences now recommends routine PFAS blood testing for the roughly 150 million Americans with contaminated water supplies. Other chemicals are likely to follow. The evidence is there. The question is whether we act on it.
Be as curious about the invisible as the visible. The evidence is already telling us we have to act.
Dr Leonardo Trasande, TEDx Great Pacific Garbage Patch, December 2025
His Book
Sicker Fatter Poorer
Dr Leonardo Trasande. Published 2019.
Trasande builds the case that the epidemic increases in chronic disease seen over the past half century, obesity, diabetes, infertility, learning disabilities and certain cancers, cannot be explained by genetics or lifestyle alone. He documents the role of endocrine disrupting chemicals in driving these conditions, quantifies the economic cost of regulatory failure, and provides practical guidance on how individuals can meaningfully reduce their exposure. Written for a general audience, it is one of the most comprehensive and readable books on this subject available.
Connects directly to: our Start Here page on endocrine disruptors, the Research and Studies page, and our Food and Nutrition guide on pesticide exposure.
Endocrine-disrupting chemicals are one of the biggest global health threats of our time. And 2% of us know about it but 99% of us are affected by it.
Dr Leonardo Trasande, NYU School of Medicine
Sources: Trasande L et al., Endocrine disrupting chemicals and disease costs (2016) | Trasande L, Sicker Fatter Poorer (2019) | WHO/UNEP State of the Science Report on Endocrine Disrupting Chemicals | TEDx Great Pacific Garbage Patch (December 2025). Some links on this page are Amazon affiliate links. Purify The World may earn a small commission on purchases made through these links at no extra cost to you.