Ontario, Canada

Wildfire smoke from sources like Ontario, Canada, caused unhealthy air pollution levels across Washington, D.C., and Lititz, Pennsylvania. Due to high Air Quality Index readings, childcare centers were forced to keep children indoors. This recurring hazard marks a new reality for places in Pennsylvania that must adapt as wildfire smoke becomes a common summer threat.

A 16-year study (2003-2019) found wildfire smoke has become the primary pollutant affecting pregnancies, contributing to risks like low birth weight and preterm births. While pollution from cars and industry declined, wildfire smoke levels increased, with 65% of days exceeding air quality standards linked to wildfires. The study analyzed 64.5 million pregnancies across 2,800 U.S. counties.

A study analyzing data from 64.5 million pregnancies between 2003 and 2019 found wildfire smoke to be the primary pollutant affecting pregnancy outcomes, including low birth weight and preterm births. The study, published in Frontiers in Environmental Health, noted that wildfire pollution has offset declines in other pollution sources, with 65% of days exceeding air quality standards linked to wildfires.

A study analyzing 64.5 million pregnancies from 2003 to 2019 found that wildfire smoke has become the primary pollutant affecting pregnancy outcomes, including low birth weight and preterm births. While pollution from cars and industry has decreased, wildfire smoke has offset these gains, with 65% of days exceeding air quality standards attributed to wildfires. Recent years, including 2020 and 2024, saw severe wildfire seasons impacting regions like Washington, D.C., Ontario, and Oregon.

A study analyzing data from 2003 to 2019 found that wildfire smoke has become the primary pollutant affecting pregnancies in the U.S., contributing to risks like low birth weight and preterm births. While pollution from cars and industry has declined, increasing wildfire smoke has offset these gains, with 65% of pollution days exceeding national standards attributed to wildfires.

A study from 2003 to 2019 found that wildfire smoke has become the primary pollutant affecting pregnancies, linked to outcomes like low birth weight and preterm births. While pollution from cars and industry has decreased, wildfire smoke pollution has increased, offsetting prior gains in air quality. The study excluded recent years with severe wildfire seasons, such as 2020 and 2024.