A new study in Environmental Science & Technology analysed more than 200,000 births in Southern California from 2006 to 2014 to examine prenatal exposure to wildfire smoke. Researchers focused on the third trimester and compared children’s autism diagnoses by age five.
They found that maternal exposure to wildfire smoke in the final three months was linked to higher autism risk. The association was strongest for mothers exposed to more than ten days of smoke; those children had a 23% higher risk of an autism diagnosis compared with children whose mothers were never exposed. The study adds to earlier research linking prenatal air pollution and autism risk.
Authors note the findings are not conclusive. They call for further work to understand how smoke exposure, biology, genetics and other environmental factors may interact, and for policies to better protect pregnant people and children.
Difficult words
- prenatal — Happening to a baby before it is born
- exposure — Contact with something harmful or present in environment
- trimester — One of three parts of a pregnancy period
- autism — A developmental condition affecting social and communication skills
- diagnosis — A doctor's identification of a disease or conditiondiagnoses
- maternal — Relating to a mother during pregnancy or childbirth
- conclusive — Showing that something is definitely true or decided
- interact — To have an effect on each other; to influence
- policy — A plan or rules made by groups or governmentspolicies
Tip: hover, focus or tap highlighted words in the article to see quick definitions while you read or listen.
Discussion questions
- Do you think governments should make more policies to protect pregnant people from smoke? Why or why not?
- What can pregnant people do to reduce smoke exposure during wildfire season where you live?
- Why do the authors want more research about how smoke, biology and genetics may interact?
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