A Conversation with Dr. Eri Saikawa

The Lister Hill Center for Health Policy recently hosted Dr. Eri Saikawa for a seminar on climate-smart agriculture and the impact of urban gardening on public health. Dr. Saikawa’s research includes evaluating the impact of fertilizer on air quality and how heavy metal toxicity in the soil of formerly red-lined neighborhoods has public health implications on the communities of Atlanta. 


When we’re talking about heavy metal toxicity and urban gardening from a policy perspective do you think it’s more important to focus on mitigation or prevention?  

I definitely think prevention. There is so much we can be doing to prevent exposure, and that’s why I think we need to be pushing for more urban testing so that we don’t put kids into unnecessary exposure. After the fact, it’s usually too late. So these lead exposures, as I understand, once you are exposed you are exposed. We really need to do a much better job to prevent that situation 

Slag dumping in neighborhoods causes high levels of lead. Are there any local or federal bills to prevent the dumping of slag in residential areas? Are there any in progress and how can we support them if so? 

This is a very good question. So, the problem with the slag dumping is that it happened a long time ago before there was legislation to prevent it. We believe that this might have happened in the 60s or so, and at that time they were considered to be non-toxic materials. That’s why they use that as the fundamentals of buildings. What we are seeing is that the EPA is working to clean up [and reduce the metals in the soil]. They told me that sometimes they’ll dig eight feet down and they were still seeing slag, and so they decided that they cannot go any deeper.  

In so many places, they dumped so, so much. Now they’re only digging up to a foot or two, and I think this is a very big problem as well. I think it is pretty prevalent in many different places, too, so how can we figure out the history. I just wonder if that’s because of the low-income neighborhood, we don’t have enough history like historical documentation on why was that area chosen [as a dumping site]. Because of that, we cannot tell from the existing documents that we could find. 

How can you test lead levels in your backyard before planting a garden? If you find high lead levels, what do you do next, and how can you decrease those? 

In Georgia, what we started doing is called the Community Science Soil Shop. We have collection boxes in different parts of the greater Atlanta area [to drop off soil samples] and then we allow people to send in the soil samples to our lab. We have a video that shows how to collect soil samples, dry them, and then they can either ship them or drop them off. Then we would analyze them for free and then give them the results. These are just screening so it’s not the full testing because we’re not saving them but I think that’s a good way to know if that might be contaminated to look into it more.  

But the second question is more important. What can you do once you know that it is contaminated? So I think this is also a problem on why people are not really willing to test. In the state of Georgia, if you find that there is lead in your soil then you have to disclose that if and when you want to sell your house. There have been several people that tell me that they found slag in their backyard, and when I asked them if we could go and take soil samples to figure out the lead levels they would say no because they want to make sure that their home value is not going to be impacted. So that’s a problem.  

Another thing though is that cleaning up can be very expensive. So if you dig, that’s the best way, but it would cost a lot of money. We have community partners asking if we can use hyperaccumulator plants as a way to take up [some of the heavy metals] so we did some testing with sunflowers, peas, and Chinese cabbage. We saw quite good results from Chinese cabbage and peas but [the heavy metals] went to the edible parts. We did these experiments in the greenhouse, but we are worried about actually doing the experiment in the field in the case that people come and then start eating them and get exposed. 

There is no good way in a cost-effective manner [to treat soil] and that is a problem. But you can do easy things [to prevent exposure] like washing hands, for example, and making sure if you have pets they wouldn’t be going into the garden and then coming back with their dirty feet everywhere in the home.

When it comes to climate change policy there is a lot of finger-pointing between industry and individual action. In your experience working with agriculture, which is more important, and what individual actions can we take that are going to make the biggest amount of difference? 

I get asked that question a lot, and I do think that we need to be pointing at the industry. Ninety percent of the emissions are potentially coming from a very small number of industries, and if they are not going to do anything then nothing is going to happen. I don’t want to say that individual actions are not important, but I do think that the companies that are really burning a lot of fossil fuel need to stop. Otherwise, even if we do everything we can, that’s not going to stop climate change. 

That being said, the individual efforts to really voice concerns to push the government and also the industry to take action is important. We see that a lot from the youth movement, and I think they are the hope. They have shown how that’s possible and how that could work, so I think we need to do that more.

Does a yard contaminated with lead have impacts for children other than eating food grown there? 

The biggest impact that you would see is actually the kids eating the soil, either consciously or unconsciously. There are kids with certain behaviors or disorders that would really want to eat the soil, and that is the biggest worry. I think it can also be airborne, too. If you’re running around in those highly-contaminated areas, then you can breathe in the lead particles. It’s not just about eating the food that’s grown in those contaminated soils.

Learn More  

Want to learn more about Dr. Saikawa’s work? Check out these recent publications. 

Invited Perspective: Assessing the Contaminant Exposure Risks of Urban Gardening: Call for Updated Health Guidelines

The terrestrial biosphere as a net source of greenhouse gases to the atmosphere 

Global soil nitrous oxide emissions since the preindustrial era estimated by an ensemble of terrestrial biosphere models: Magnitude, attribution, and uncertainty

The impact of cold weather on respiratory morbidity at Emory Healthcare in Atlanta

Keeping in Touch 

Follow Dr. Saikawa on Twitter!

More information on the Atlanta-based soil contamination investigation can be found at https://atlsoilsafety.com/

Be sure to check out her podcast, AmpliFIRE, which aims to equip listeners to accelerate climate action by providing accessible information; amplifying diverse voices; and highlightingthe intersections of environmental issues.