Agency collaboration and researcher partnerships have been the keys to the success of the Harmful Algal Bloom Research Initiative (HABRI) since it began in 2015. With more than $7.5 million invested so far, the initiative aims to address Ohio’s harmful algal bloom problem, both in Lake Erie and in its watershed.
Fifty-four science teams at ten Ohio universities, funded by the Ohio Department of Higher Education, are on the case: working with front-line health, environmental and agricultural agencies, as well as water treatment plants and coastal communities, to bring them the answers they need to get the state – and region – ready to deal with HABs from all angles.
The third round of funded projects recently reported in from their first year of work, and researchers are making promising progress on solutions for tracking blooms, protecting drinking water, reducing public health impacts and supporting sustainable agriculture efforts. Some of their findings are presented here.
Track Blooms from the Source
Building a Better Satellite for Harmful Algal Bloom Monitoring
Dr. Catharine McGhan, University of Cincinnati
Satellites equipped with sensors that target harmful algal blooms offer early warning systems for drinking water protection, as they allow scientists and water managers to track blooms and their movements on a large scale. However, current satellite monitoring efforts are limited to days without cloud cover and very coarse imagery from a small number of expensive satellites available to researchers.
HABRI scientists are working together with UC CubeCats, an undergraduate engineering student group at the University of Cincinnati, to incorporate a much less expensive system for cyanobacteria detection into a CubeSat, a type of small standardized satellite that the students are designing. This detection system will operate effectively in space, gathering useful imagery from low Earth orbit. The system looks for the presence of phycocyanin, the blue pigment that gives cyanobacteria in some toxic and nontoxic “algal” blooms their color.
The project has already trained a number of undergraduate students who were able to contribute original research on various components of the satellite, including working with suppliers and presenting results at conferences. The research team is now moving into the fabrication stage, as well as testing solar panels and targeting methods for the satellite’s sensors. The imaging sensors will be tested on small aircraft during the spring of 2020 to prepare for integrating them into the satellite.
Once completed and placed in orbit, the satellite will supply imagery of the Great Lakes that allows for the early detection of harmful algal blooms for up to two years. The data will be received by a ground station at the University of Cincinnati, which is currently being upgraded to support this mission.
The researchers will use the satellite images to better understand how algal blooms grow and move in the Great Lakes, and to support other early warning systems that help protect drinking and recreational waters for the region’s residents. Lessons learned from this satellite development will also inform future monitoring satellite systems.
Produce Safe Drinking Water
Using Bacteria to Remove Microcystin From Drinking Water
Dr. Jason Huntley, The University of Toledo
Many Ohio communities draw their drinking water from Lake Erie, so making sure that any harmful algal bloom toxins are removed before the water reaches consumers is essential to maintaining public health. While water treatment plants currently use activated carbon to treat for algal toxins, researchers are developing new approaches that use microcystin-degrading bacteria to remove toxins from their source water.
State agencies like the Ohio EPA and the Ohio Department of Health have expressed a need for new technologies that drinking water plants can use to remove algal toxins from their raw water. In particular, they require ways to effectively treat low levels of toxin without incurring the same cost required to remove higher toxin levels from the water.
HABRI researchers are now exploring biofilters, built by growing bacteria in thin layers called biofilms on solid surfaces, which could potentially purify drinking water that contains low levels of algal toxins. The bacteria they are using occur naturally in freshwater, and have been shown to break down microcystin toxin into non-toxic component parts. The researchers have already filed provisional patents on this technology.
Their current work focuses on determining the right combination of bacteria to grow, to ensure that the largest amount of toxin is removed from the water. In addition, they are scaling up their previous bench-scale laboratory experiments from small filters to a filter size more likely to be used in a water treatment plant.
To make sure the bacteria do not pose a separate threat to human health, the scientists are also working on genetic sequencing for the biofilter bacteria to make sure they won’t be able to cause disease in humans. Once the bacterial DNA is sequenced, the researchers hope to also use that information to potentially identify the specific enzymes responsible for breaking down microcystin into non-toxic compounds.
Protect Public Health
How Does Microcystin Affect Liver Cancer Development?
Dr. Thomas Knobloch, The Ohio State University
Harmful algal blooms can release toxins that affect the liver, kidneys and heart, as well as the digestive and nervous system in people and animals. Exposure from drinking contaminated water is most common, and can be either chronic, such as from drinking water that contains minute amounts of toxin daily over a long period, or acute, such as swallowing water with high levels of toxin just once while swimming in a contaminated lake.
Long-term and high doses of algal toxins can lead to an increased risk for liver cancer, but researchers don’t really know how dosage and chronic or acute exposure affect that risk. HABRI scientists are now working to better understand the mechanisms of algal toxin damage, as well as whether dosage and timing of exposure changes those mechanisms.
Microcystins, the toxins that most Lake Erie harmful algal blooms produce, cause tissue damage in liver cells, which can turn into liver cancer with prolonged or concentrated exposure. This damage can exacerbate problems in patients with pre-existing liver disease such as non-alcoholic fatty liver disease, one of the most common pre-existing liver conditions. The researchers are using mice to mimic both short-term concentrated exposure to algal toxins, such as would happen on a weeklong vacation to a contaminated beach, and long-term exposure to levels generally considered safe to drink.
Results showed that liver damage in mice exposed to high doses of microcystin was higher the more toxin they had ingested. Other systems like kidneys and reproductive organs were also affected. Unexpectedly, three of four mice that died early in the study were female, suggesting that although liver cancer is more common in males, acute impacts of algal toxins may be more severe in females.
The mice exposed to low levels of microcystins developed more pre-cancerous and liver tumors than control mice, especially in high-risk individuals with pre-existing liver disease. So while microcystin alone or in healthy individuals may not pose a significant health risk at low doses, exposure in high-risk populations can promote damaged liver cells to become cancer cells.
The researchers continue to study the mechanisms involved in producing this liver damage, in the hopes of eventually finding biomarkers that let them predict who may be at greatest risk for toxin-induced liver cancer before it develops.
Developing a Better Manure Fertilizer
Dr. W. Robert Midden, Bowling Green State University
Manure from concentrated animal feeding operations (CAFOs) can negatively impact water quality. If too much is applied to too little land, this can lead to relatively large amounts of nutrients in field runoff. The same manure can also be used as a beneficial agricultural fertilizer, but the cost of transporting it to fields is often high relative to its fertilizer value because of the high water content.
HABRI researchers are developing a low-cost treatment for manure from concentrated animal feeding operations, focused on separating manure nutrients from wastewater and producing a dry product that could reduce transportation cost by 20 to 40 times. That dry product would also release nutrients more slowly into the soil, thus enhancing crop yield and improving water quality.
In the past year, they treated 3000 gallons of liquid manure from a dairy CAFO with a wastewater treatment coagulant that allowed them to separate solid and liquid manure components and ensure that nutrients remained in the solid portion. They compared this treated manure to raw manure by placing it on experimental farm fields, tilling the fields to incorporate the fertilizer and then planting soybeans. During this pilot test, water samples were collected during rain events and analyzed for agricultural nutrients.
Results show higher phosphate concentrations in runoff from plots fertilized with raw manure, compared to plots that received the treated manure solids. Crop yields from both field types were similar, suggesting that plants can absorb nutrients from the treated manure just as well as from the raw manure. Overall, the treated manure seemed to have a positive impact on reducing agricultural nutrients in runoff from farm fields.
The researchers are also working on a way to trace nutrient runoff back to its source based on organic nitrogen and phosphorus compounds that are specific to where the runoff came from. They are identifying specific compounds present in each type of manure treatment, along with contaminants like hormones and antibiotics potentially present in manure from large animal operations in order to determine whether the treatment process can help prevent problems from these substances.
Future funding will hopefully expand their experiments to manure from swine facilities, and to testing new polymers they have developed in the lab that offer performance advantages and possible cost savings.