Everybody advocates for clean drinking water and pristine lakes, but not everybody would be comfortable using synthetic biology to achieve these goals. Our team examined the current legislation in place to control and define safe levels of microcystins, especially in New York, to set parameters for our bio-reactor and boat. To expand upon our knowledge, we interviewed local legislators to hear firsthand the new laws and policies being created in response to increased HAB appearances in recent years due to climate change. Additionally, we interviewed experts in marine biology and freshwater systems, as well as volunteers on the frontlines combating the effects of HABs in the Finger Lake region, to ensure we have a comprehensive understanding of the situation so we can harness the full potential of our proposed system.
- Legislation on HABs have been in place for years, but recently, the interest in HABs has increased substantially. Legislative proposals are being considered to address the increase in HAB occurrences, especially around the Cayuga Lake region.
- Although current methods of prevention and treatment are sufficiently effective, they are also costly and time-consuming. New systems to detect and breakdown microcystins would improve both safety and cost-effectiveness.
- HABs are dangerous to humans and are of increasing concern, mainly due to climate change that has likely contributed to more frequent appearances.
To take reHAB to widespread use, our project needs to abide by current legislation for HAB remediation. We
first looked into the legislature on the federal level regarding water quality. The Clean Water Act of 1972
set standards for chemical discharges from companies [1], but it wasn’t until 1998 that Congress recognized
the severity of harmful algal blooms and passed the Harmful Algal Bloom and Hypoxia Research and Control Act
(HABHRCA)[2].
The HABHRCA, passed in 2004 and most recently re-authorized in 2017, provides funding for the National
Oceanic and Atmospheric Administration (NOAA) to continue research on the ability to detect, monitor and
assess HABs. For this purpose, 13.5 million dollars was allocated to the NOAA, with this amount increasing
in small increments until 2023 [3].
While these legislative acts helped us key into the current state of HAB remediation research, we found that
the primary effort for HAB remediation takes place at the state and local level. For the State of New York,
Governor Andrew Cuomo introduced a four-point initiative to combat HABs in Upstate New York [4]. While the
initiative provides $65 million to identify, prioritize and develop action plans for vulnerable lakes [5],
the efforts are largely focused on the prevention and identification of blooms, whereas our project is more
concerned with the detection and remediation of blooms already in existence.
Focusing on local policies here in Ithaca, our team decided to attend a public meeting of the Planning,
Energy, and Environmental Quality Committee from the Tompkins County Legislature. The meeting covered a
broad range of topics related to the environmental concerns of Tompkins County rather than focusing on HABs,
so we decided to contact Deborah Dawson, who is the Chair of the Committee. Our goal with reaching out to
Mrs. Dawson was to get a firsthand account of what sorts of limiting factors affect the initiatives that are
currently being undertaken to address the issue of HABs in the Finger Lakes region. Mrs. Dawson explained to
us how the process involved in implementing new approaches differed between the lakes based on how the area
was divided up among the neighboring counties. She mentioned that it is easier to address HABs concerns in
smaller lakes due to the fact that only a single county has to devote its resources to remediation and can
prioritize their level of concern. With larger lakes, such as Cayuga Lake, which is divided between three
counties, there must be an active collaboration initiative. This can be difficult to coordinate, as each
county may have different priorities and concerns for lake health. Mrs. Dawson’s insights pushed us to
consider how to best integrate our designs into the established network of programs and individuals involved
in tackling the issue of HABs.
Overall, we learned that the majority of legislation for HABs exists at the national and state level.
However, most of this legislation is broad and geared towards research. On local levels, where there is a
more central focus on the issue, there is still a lack of comprehensive legislation, as many initiatives are
still being discussed. By working with legislators and community leaders, our team hopes to use our project
to push these initiatives forward to provide clean and safe waters for our community and the world.
Comprehensive Environmental Assessment (CEA) is a type of risk assessment that incorporates the two
traditional assessment approaches: risk and life cycle assessment.
The advantage of life cycle assessment (LCA) is in its wide scope; it considers all steps of manufacturing,
usage, and disposal or recycling of the chemical or product. Risk assessment (RA) is advantageous in that it
specifically quantifies the risk, providing a resolution through the analysis. CEA aims to combine the
strengths of both assessment techniques by providing a guideline for organizing information from various
stakes and making transparent judgements based on the input. [1]
This framework is currently used by the U.S. Environmental Protection Agency. As our project intends to
provide a robust solution for harmful algal blooms and therefore necessitates direct interaction with the
environment, we must assess the long-term impacts of our project on the environment. The comprehensive
environmental assessment of our project focuses on the genetically altered bacteria Escherichia coli
and the potential impacts the altered bacteria may have on the environment.
Our project aims to develop E. coli that can degrade microcystins, a primary toxin that is produced by harmful algal blooms. Our project involves two steps: detection of microcystins in water and remediation of said contaminated water. The first step, detection, involves using naked RNA to sense microcystins. Our team is aiming to create an aptamer-based sensor to recognize microcystins. The second step involves engineering the mlr cassette into E. coli to breakdown the toxins. The mlr cassette is a series of six genes that gives E. coli the ability to degrade microcystins, including mlrA, mlrB, mlrC, mlrD, mlrE, and mlrF that each take on different roles in breaking down the toxins. For instance, mlrD produces the genes responsible for transporting the microcystins into the cell. To carry out the degradation more efficiently, some mlr genes are designed to be transported to the cell’s periplasm.
In the event that our detection and remediation system gets integrated into drinking water treatment facilities, or is used for instantaneous lake testing and feedback, competition and biodiversity would be the main concern regarding the modification of E. coli. However, our current system isolates the bacteria from the freshwater ecosystems to avoid the risk of horizontal gene transfer. Regardless, our team has taken steps to ensure the containment of the modified bacteria by immobilizing them on alginate beads. Moreover, we are strategically placing filters in the inlet and outlet of the reaction chamber to ensure that microcystins can enter the system but bacteria would not be able to get out.
Since our altered genes produce proteins that give metabolic strain on themselves, there exists a low possibility that the engineered strains would outcompete wild strains when used in a setting outside of the lab. There does exist a possibility that the antibiotic resistant genes may be transferred to other bacterial strains. However, auxotrophy can serve as a potential solution to eliminate such genes. Auxotrophy is the inability of a gene to synthesize organic compounds needed for growth. By implementing auxotrophy onto the altered E. coli, we can decrease the possibility of the altered genes being transferred to other bacterial strains.
Solutions, such as biocontainment techniques that isolate the bacteria from the environment, can be used to prevent horizontal gene transfer (HGT) of antibiotic resistant genes from the mutated genes to the environment. We are approaching the problem of HGT from a mechanical angle to implement physical barriers between the bacteria and the environment in order to prevent contamination and gene transfer.
The main environmental concerns about the modified E. coli genes would pertain to the possibility of
the mutated genes affecting the environment through gene transfer. Despite working primarily with the
engineered bacteria in a laboratory setting, our team has also designed filters in the reaction chamber to
provide a physical barrier that prevents the modified bacteria from entering the environment.
Another crucial part of our project is the boat, whose main purpose is to gather samples from the lake and
use GPS capabilities to record the coordinates of our sample collection sites. The boat also operates on an
automated driving system that allows it to move to various GPS coordinates via motors. To ensure that no
microplastics decompose into the water, the boat was made using plexiglass.
When looking at boat usage in areas, such as Cayuga Lake, it is important to consider relevant laws and
regulations. According to the Tompkins County boat laws, it is permitted to drive a boat on the lake under
the speed limit, 5MPH within 100 feet of shore and 10 MPH between 100 feet and 500 feet of shore. Users are
also required to use enzyme-based cleaners to reduce the impact done on the water. [2] Our boat is able to
be programmed to travel at a speed below the specified limit and runs no risk of a potential oil spill since
it runs on battery power, which eliminates the need to use cleaners to purify the water.
In addition to the comprehensive environmental assessment and safety and risk assessment, we also considered
the potential harm that our project could have on the environment in the context of bioethics.
The main goal of our project is to provide an alternative method of addressing harmful algal blooms (HABs)
in Ithaca. We aimed to provide a solution targeted specifically towards the Ithaca community by speaking
with farmers, local community members, and the Tompkins County Council. HABs cause great harm to both humans
and marine animals and have drastic impacts on the environment. HABs create harmful toxins called
cyanotoxins that can lead to various illnesses and diseases. In regards to marine life, the algal blooms
block sunlight and create dead zones (areas with low oxygen levels) leading to the destruction of habitats.
Whereas other existing solutions focus primarily on preventative measures against toxin contamination, our
project provides a novel post-contamination solution since effective long-term and short-term solutions are
necessary to successfully mitigating the issue.
Although there is some concern that the altered E. coli used in our project may impact the
environment and
disrupt local ecosystems, we have put various safety constraints in place. These are mentioned in the CEA
section, and our project takes great care to address these potential impacts on the environment.
Currently, there are a few steps that take place when trying to collect water samples and identify the
presence of microcystins. Most samples are collected by volunteers from local organizations, meaning
collections tend to be free or inexpensive. After samples are collected, there are multiple ways to test for
the presence of microcystins. The most common way is through an ELISA, which ranges from $125 to $200
dollars per toxin[1]. The most common price for a test, however, is $125 per toxin.
Another variable in this analysis is the uncertainty of receiving results. From our conversation with Julie
Lockheart from Owasco Lake Association, results from the samples take up to three weeks to process and
analyze. By this time, microcystins degrade naturally and the results would not be effective in preventing
damage from the toxins. Our boat serves as a replacement for volunteers and collects samples based on areas
in the lake where HABs are most common. Although the boat costs around $200, it saves time by acting as an
automated sample collector with high-resolution data capabilities. It can work throughout the day, mapping
locations of blooms around the lake. The DNA aptamers with the gold nanoparticles serve to replace ELISA
kits and remove the issue of waiting for results. The gold nanoparticles cost approximately $150 for 25
mL[2] and the aptamer cost around $10[3]. Our system is functional for 130 uses. This is significantly more
economical than the $125 per toxin charged by laboratories to test using an ELISA.
At the moment, the price of clearing microcystins ranges widely. In a report done by the American Water
Works association, depending on how long the treatment is, it could vary from $178 for 3 days of prevention
and treatment to $280,000 for 3 months of prevention and treatment of cyanotoxins[1]. This is compared to
our project, which only requires $500 to build a small scale bioreactor that can last a significantly longer
time.
Damage caused by microcystins varies greatly depending on the water treatment facility and the amount of
time the plant was exposed to the microcystins. One of the worst cases of cyanotoxins affecting drinking
water was in Toledo, Ohio. The water plant in the city had to spend $54 million dollars on a new treatment
facility to remove contaminants like microcystins[4]. This is, however, an extreme case, where Toledo was
exposed to large amounts of microcystins for a long period of time. Regardless, this demonstrates the damage
microcystins can do to water treatment facilities.
The damage caused by microcystins can be negated by the early detection offered by the aptamer system.
Treatment would also be low-cost and effective. The bioreactor costs less than $500 taking into
consideration the alginate beads, the materials to make the actual reactor, and the engineered bacteria[5].
The alginate beads also last several years without degrading, so replacing the alginate beads would not be
costly. Given the economic advantages of our system over existing methods of detection and remediation, our
product would allow for more cost-effective treatment of microcystin contamination to better protect
communities exposed to the dangers of HABs.
[1] History of the Clean Water Act. (2017, August 8).
https://www.epa.gov/laws-regulations/history-clean-water-act.
[2] HABHRCA. (n.d.). https://coastalscience.noaa.gov/research/stressor-impacts-mitigation/habhrca/.
[3] Harmful Algal Blooms and Hypoxia Research and Control Amendments Act of 2011, November 13, 2012, 112-2
Senate Report 112-237, Harmful Algal Blooms and Hypoxia Research and Control Amendments Act of 2011,
November 13, 2012, 112-2 Senate Report 112-237 (2013).
[4] Governor Cuomo Unveils 12th Proposal of 2018 State of the State: Protecting New York's Lakes From
Harmful Algal Blooms. (2017, December 21).
https://www.governor.ny.gov/news/governor-cuomo-unveils-12th-proposal-2018-state-state-protecting-new-yorks-lakes-harmful-algal#_blank.
[5] Harmful Algal Bloom (HAB) Action Plans. (n.d.). https://www.dec.ny.gov/chemical/113733.html.
[6] Harmful Algal Bloom Action Plan Cayuga Lake, Harmful Algal Bloom Action Plan Cayuga Lake1–124 (n.d.).
https://www.dec.ny.gov/docs/water_pdf/cayugahabplan.pdf
[7] 33 U.S. Code Chapter 53 - HARMFUL ALGAL BLOOM AND HYPOXIA RESEARCH AND CONTROL. (n.d.).
https://www.law.cornell.edu/uscode/text/33/chapter-53#.
[8] Britannica, T. E. of E. (n.d.). Environmental Protection Agency.
https://www.britannica.com/topic/Environmental-Protection-Agency.
[1] Powers, Christina M., G. Dana, P. Gillespie, M.R. Gwinn, C. O. Hendren, T. C. Long, A. Wang, J. M.
Davis. “Comprehensive Environmental Assessment: A Meta-Assessment Approach.” Environmental Science and
Technology. Sep. 2012. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3439956/
[2] “Clean Up Your Act: Boat Clean!” Tompkins County Water Resources Council. 2007.
http://tompkinscountyny.gov/files2/planning/committees/WRC/documents/ItstheLawbrochure2007.pdf
[1] “Laboratories that will accept samples for Harmful Algal Bloom (HAB) toxin analysis.” Environmental
Protection Agency. June 2016.
https://www.epa.gov/sites/production/files/2016-06/documents/hab_toxin_labs_list.pdf
[2] “Gold nanoparticles.” Millipore Sigma.
https://www.sigmaaldrich.com/catalog/product/aldrich/741957?lang=en®ion=US
[3] “DNA oligos.” Integrated DNA Technologies.
https://www.idtdna.com/pages/products/custom-dna-rna/dna-oligos/custom-dna-oligos
[4] Schechinger, Anne. “The Huge Cost of Toxic Algae Contamination.” AgMag. June 2019.
https://www.ewg.org/agmag/2019/06/huge-cost-toxic-algae-contamination
[5] “Sodium Alginate.” VWR. https://us.vwr.com/store/product/8887847/sodium-alginate