Skip to main content

Breadcrumb navigation:

Eagle Addresses Vatican Conference on Autism

By BCEEAN Newsletter Staff

Dr. Philip J. Landrigan '63, Dean for Global Health at the Icahn School of Medicine at Mount Sinai, outlined the role of environmental exposures in causing autism.

In November 2014, Dr. Phil Landrigan '63, Dean of Global Health at the Icahn School of Medicine at Mount Sinai, addressed the 29th International Conference of the Pontifical Council for Health Care Workers. 

The Council, instituted by Pope John Paul II in 1985, exists to support health care workers who serve the sick and suffering. It is also tasked with studying the implications of health care policies and programs for pastoral care and spreading Church teaching on health issues. 

The Council’s 29th International Conference focused on autism – the first-ever Vatican conference to do so. Entitled “The Person with Autism Spectrum Disorders: Animating Hope,” the three-day gathering was designed as an interdisciplinary exchange featuring approximately 650 experts from nearly 60 countries. People affected by autism, their families, parish groups, and associations concerned with autism also attended. 

The conferees studied autism from a medical, psychological, familial, social, pastoral and religious viewpoint. They addressed such topics as diagnosis; research, prevention, and treatment; culture and education; and pastoral care. 

Landrigan told the conferees that, while genetic factors play a role in causing autism, they account at most for no more than 30-40% of cases – and they cannot easily explain recent dramatic increases in the prevalence of autism, even after accounting for improved diagnosis and reporting in more recent years. Landrigan concluded: “It is therefore highly probable that early environmental exposures also contribute to causation, perhaps acting in concert with inherited susceptibilities.” 

Evidence for an environmental contribution comes from both “studies demonstrating the exquisite sensitivity of the developing brain to external exposures” and “studies specifically linking autism to environmental exposures.” The latter category includes studies linking autism to prenatal exposure to thalidomide, the anti-convulsant valproic acid, and the widely used insecticide chlorpyrifos. Recent studies have also found an elevated prevalence of autism among children exposed during gestation to elevated levels of traffic-related air pollution.

Landrigan expressed concern over both the ubiquity of potentially harmful environmental chemicals and the dearth of toxicity testing.  Today there are over 80,000 chemicals in commerce – mostly synthetic chemicals invented in the past fifty years. Three thousand of these chemicals are produced in quantities greater than 1 million pounds per year. These chemicals are found in a great array of consumer goods, cosmetics, medications, motor fuels, and building materials. The blood and urine of nearly all Americans, human breast milk, and the cord blood of newborn infants contain measurable quantities of several hundred synthetic chemicals. 

A recent systematic literature review identified approximately 200 industrial chemicals documented to be neurotoxic in adult humans.  The same study identified another 1,000 chemicals that have not been examined in humans, but are known to be neurotoxic in experimental animals. Landrigan reasoned: “Given current knowledge of the vulnerability of the developing human brain, likelihood is high that many of the chemicals identified through this search have potential to cause injury to the developing human brain” as well.

This would seem to argue for widespread, rigorous toxicity testing, but the opposite scenario prevails. Landrigan noted: “Only approximately half of the most widely used chemicals have been subjected to even minimal toxicological screening. Fewer than 20% of these widely used chemicals have been examined for their potential to damage the developing nervous system.”

Landrigan called the paucity of toxicity testing “a grave lapse of stewardship.” He elaborated: “It reflects a combination of industry’s unwillingness to take responsibility for the products they produce coupled with long-standing failure of governments to require toxicity testing of chemicals in commerce.”

Landrigan observed: “There is substantial imbalance between the highly sophisticated information on the genetics of autism and the lack of data on potential environmental causes.” He recommended an interdisciplinary, systematic strategy to discover the undiscovered environmental causes of autism. Such a strategy, he emphasized, should combine toxicological screening, neurobiological research (to discover how toxic chemicals interact with the developing brain), and prospective epidemiological study on environmental exposures in pregnancy. He predicted the “likelihood is high” that such a strategy could yield breakthrough results and evidence-based prevention.  

Join the BCEEAN Social Networks!

Stay connected with fellow members of BCEEAN through our Facebook page and ever-growing LinkedIn group.

Help Out a Fellow Eagle

If you have energy or environmental sector internship or job shadowing opportunities for current BC students, please contact BCEEAN at

Help Grow BCEEAN

If you know alumni who might enjoy participating in BCEEAN, please circulate this newsletter to them and invite them to join us at More information about BCEEAN can be obtained from our

Light the World Campaign