Noah Haggarty from the Los Angeles Times recently interviewed LA Fire HEALTH Study scientists Joseph Allen, Lindsey Burghardt, and Kari Nadeau about their new commentary arguing that lead safety levels for soil should be lowered to reflect new findings and our current understandings of how lead impacts human health, particular in young children.

In a paper out Friday, Harvard environmental health researchers argue it’s not strict enough. The scientists contend that the state’s health standard is not based on sound science and should sit around 55 milligrams per kilogram of soil (a measure also referred to as “parts per million”) instead.

“We’re getting asked these questions every single day, like every other scientist … ‘Is it safe for my kids?’ ” said Joseph Allen, lead author on the paper and a Harvard T.H. Chan School of Public Health professor who has been working with fire survivors through the LA Fire HEALTH Study research program. “I can’t look at somebody in the eye anymore, knowing what I know about these models, and tell them yes.”

While the commentary argues that lead standards should be stricter, the article also points out that this may not impact fire survivors all that much:

Given all the uncertainty in lead modeling — and the wide range of sensitivity different kids may have based on their health conditions and how much they play in the dirt — many researchers say concerned residents should focus on their own risks and think about lead levels as “much lower than the standard,” “close to the standard” and “much higher than the standard” instead of obsessing over differences in digits.

For example, much higher levels in soil that’s about to get covered with a new concrete foundation might not matter all that much. Levels close to the standard in the yard of a home with no kids may not matter if the residents aren’t avid gardeners and always take their shoes off when entering the house.

On the flip side, even lower levels in the soil in an area where a 2-year-old likes playing in the mud could pose a risk that’s unacceptable for a resident.

Read the full article here: https://www.latimes.com/environment/story/2025-08-11/scientists-argue-for-stricter-lead-soil-contamination-standards

View the Lead in Soil Fact Sheet from the Department of Environmental Health at Harvard T.H. Chan School of Public Health.