Cyanobacteria Harmful Blooms (CHAB’s) and Harmful Air Particles (HAP’s) in your Neighborhood
A funny thing happened over the Covid years of avoiding large groups …..With special permission, University researchers were granted time to work with the Chowan Edenton Environmental Group to conduct outside laboratory work.
We followed specific protocols of masking and safe-distancing while the work of filtering samples and collecting data continued throughout the summers of 2020 and 2021. The Chowan Edenton Environmental Group worked with aerosol researchers on a special project designed to measure air particles (2.5 μm in diameter or PM2.5) that might be given off during an algal bloom. These tiny particles are the size that gets into our lungs and can be the cause of respiratory problems.
The researchers from UNC-CH School of Public Health and UNC- IMS, installed EPA particle collectors at two locations in Chowan County (Chowan Beach and Pembroke Creek).
The collected particles were analyzed for size and chemical composition, including microcystins (a type of cyanobacteria toxin), and any algal particles that aerosolized above a bloom were genetically identified. Constant measures of water quality and weather conditions at these locations were added to the dataset for trend analysis. This work is complex, with many factors, such as wind, air pressure, etc., influencing whether or not tiny particles are aerosolized into the airshed above a bloom. Outcomes from this 2020 research indicated that:
- No microcystins were quantified in the airshed of the Chowan River in 2020 (MC production low throughout study)
- Several toxigenic, bloom forming cyanobacteria were identified in PM2.5
- Aquatic cyanobacteria influence the abundance of airborne cyanobacteria
- Dolichospermum, Microcystis and Aphanizomenon were aerosolized concurrently (these three genera are the most common cyanobacteria we find in the Chowan River)
- CHAB activity was linked to elevated PM2.5 mass concentrations
During Dolichospermum HAB event (late June-early July, 2020) the median PM2.5 mass concentration increased to 10.5 μg m-3 significantly above the non-bloom background of 5.81 μg m-3.
This ongoing aerosol work has resulted in funding from a Community Collaborative Research Grant for installing citizen particle collectors (purple air sensors) all over Northeastern North Carolina.
More about the benefits of the purple air sensors in the next article – stay tuned.
Questions? Email the CEEG at ceeg2007@gmail.com and follow the CEEG on Facebook.
Images: Courtesy of CEEG.
