Pond Scum Linked to Health Concerns, Maybe Lou Gehrig’s
The Lake Effect
Thursday, April 06, 2017 10:22 AM
About a decade ago a hospital in New Hampshire started to notice that many of their patients with Amyotrophic lateral sclerosis (ALS), or Lou Gehrig’s disease, lived near a local lake.
Midcoast ponds and lakes that commonly have cyanobacteria blooms include Lily Pond in Rockport, Duckpuddle Pond in Nobleboro, and Unity Pond.
Blue-green algae, or cyanobacteria, blooms on a northeastern lake. (Photo courtesy The Mitchell Center)
ALS is a fatal neurological disease that affects the spinal cord, wastes muscles and eventually collapses the lungs. There is no cure. Scientists know there is a genetic link for up to 10 percent of cases, but researchers think there may be an environmental trigger.
Further research by a Dartmouth-Hitchcock Medical Center neurologist proved that there were more ALS patients living within a half mile of the lake afflicted with algae blooms than would normally be found in the general population. It was an ALS hot spot. Residents near the lake were 10 to 25 times more likely to contract the disease.
Specifically, researchers were interested in blue-green algae, now more commonly referred to as cyanobacteria, and a cyanotoxin sometimes associated with it that affects the nervous system: BMAA.
New name, growing threat
In Maine, the explosive growth of cyanobacteria typically results in pea-green water, but affected lakes can turn blue-green to brownish-green. Sometimes lakes smell fishy or moldy. Sometimes algae creates foam or scum or streaks the shoreline blue or green.
Not all algae blooms in lakes are caused by cyanobacteria and not all create cyanotoxins that are potentially lethal. There is a lot that is still not known.
But enough is known about the effects of cyanobacteria that water quality experts and researchers in New England see an emerging public health threat as blooms become more common.
In 2015, the U.S. Environmental Protection Agency (EPA) released drinking water criteria for one cyanotoxin found in Maine waters (microcystin LR), and in December 2016, the EPA waded in with guidelines for recreation around affected lakes.
While some states have established safe levels of cyanotoxins related to drinking water, the federal government hasn’t and neither has Maine.
Development + Strong Storms = Algae Blooms
Algae blooms in once-clear lakes happen in steps and are typically connected to shoreline development, agriculture, and rainstorms.
In a balanced lake, cyanobacteria are a beneficial part of the lake ecosystem, giving off oxygen and providing food for minnows, but an extra abundance of phosphorous and nitrogen carried into lakes acts as a super-fertilizer.
As small camps along New England lakes get turned into big homes and excavators move earth with improper silt fences or other erosion controls, and shrubs and trees that act as filters to keep lakes clean are removed and replaced with driveways and lawns, the liklihood of a bloom ratchets up.
Add in heavy rainstorms, which have become more frequent in New England and which climate scientists predict will continue to increase, and soils and lawn fertilizers wash into lakes along with their payload of phosphorous and nitrogen.
Algae takes over, creating an oxygen-deprived feedback loop that is clearly death on trout.
Not all toxins from cyanobacteria are created equal. Some create swimmer’s rash, some sicken or kill pets; fish and the people who eat them are affected by others. Some target digestion and organs. It is known that the neurotoxin BMAA becomes concentrated in freshwater fish and researchers have also found high concentrations in the spiny lobsters from the warm coastal waters of Florida Bay.
Other cyanotoxins make their way into vegetation, including vegetables. Some end up in public drinking water supplied from lakes.
And perhaps the most challenging problem for scientists: cyanotoxins also drift away from the lakes as misty air.
The connection between lakes and ALS
The New Hampshire lake turned out not to be an isolated ALS hot spot.
In 2014, researchers led by Nathan Torbick at Applied Geosolutions reported ALS was more prevalent near and around murky waterways across northern New England, including Lake Champlain in Vermont and some coastal communities in Maine and New Hampshire.
Scientific American reported the kicker in Torbick’s research. People in the study areas living within 18 miles of lakes with poor water quality caused by sewage and nitrogen-rich fertilizers were 167 percent more likely than the general population to be living in an ALS hot spot.
The correlation between incidences of ALS and lakes afflicted by cyanobacteria blooms is statistically sound. That doesn’t mean that scientists know if the BMAA neurotoxin is the environmental trigger for ALS.
Researchers, technologists, lake volunteers, and water quality specialists from the U.S. EPA, the Maine Department of Environmental Protection (DEP), and the Maine Center for Disease Control (CDC) spoke about the connections between cyanobacteria blooms and human health at the 2017 Maine Sustainability and Water Conference on March 30.
Sponsored by the University of Maine’s George J. Mitchell Center for Sustainability Solutions and the U.S. Geological Survey, the annual water conference, which attracted almost 400 people this year, provides both a deep and a broad look at the role of water in Maine.
The Mitchell Center’s role is to bring together a wide range of people interested in forest management, solid waste, renewable energy and water quality to work together where their interests in environmental, social, and economic issues overlap.
When it comes to water, that is just about everyone in the state.
A Public Health Concern
Over the past two years, the concern over the public health threat caused by cyanotoxins prompted more data collection and research.
At the University of Maine Climate Change Institute, graduate biomedical science and engineering student Matthew Kruger is looking at the link between lakes, BMAA, and the role the warming climate plays in the increasing number of cyanobacteria blooms.
So far, Kruger has collected samples in 10 Maine lakes, including China Lake and Unity Pond, both of which are reported by the Maine DEP to have recurring blooms. The BMAA tests will be in by fall, Kruger said.
Midcoast ponds that commonly have cyanobacteria blooms include Lily Pond in Rockport and Duckpuddle Pond in Nobleboro, according to the Maine DEP.
The Maine CDC is focusing on lakes used as public water supplies.
Jessica Meeks, from the CDC Drinking Water Program, spoke at the conference about a statewide study started in 2016 in partnership with the Mitchell Center to collect surface water field data, research the historical record, and coordinate efforts with water companies.
Preliminary results show low concentrations of surface cyanotoxins in public water supplies, but last year was a dry summer with limited runoff.
More research is planned for this summer.
The research could potentially lead to cyanotoxin standards for the state’s drinking water.
Torbick, who did not attend this year’s conference, said his research continues, including in Maine where regional hospitals track ALS patients, recording where they live and what activities they do in or near lakes.
Torbick said different teams were approaching the relationship between cyanobacteria blooms and public health in different ways, including analyzing blood and tissue samples from ALS patients; conducting surveys about occupation of ALS patients and lifestyle risk factors like smoking; researching connections between methylmercury (another known neurotoxin) and BMAA, fish and the food web; and analyzing how airborne mists disperse toxins.
“This is complicated,” said Torbick.
It is science at its messiest. BMAA may also have a role in other neurological diseases such as Parkinson-Dementia Complex and Alzheimer’s, according to Torbick.
“There are a lot of moving parts,” he said.
Local lake volunteers crucial to science
Citizen science plays an increasingly important role in data collection. For cyanobacteria-related research, lake association and watershed volunteers are key to collecting a large amount of precise field data. Torbick said he relies on it and the public data available from agencies like the Maine DEP.
Smartphones have made that volunteer data collection easier and more reliable.
At the Water Conference, Hilary Snook from the EPA New England Regional Laboratory discussed new technology using smartphones that allow citizen scientists with little or no training to send raw data to researchers.
Bloomwatch, a new smartphone app, allows people to snap a photo of an algae bloom and upload it directly into a citizen science database which automatically records the date, time, conditions, and map location of the data (cyanos.org/bloomwatch). The updated Bloomwatch app is new. Only one lake in Maine was recorded in Bloomwatch last fall. This summer the app is likely to get a lot more use.
It’s as easy as taking a photo and hitting send. The photos and map data are also easily searchable by anyone interested in a particular lake.
The Cyanoscope, another field collection tool used by volunteers, requires simple training, which Snook travels to lake associations to provide. Volunteers tow small field equipment behind a boat to collect a water sample, prep microscope slides and attach a smartphone to a field microscope for a close-up look at the algae, followed by basic field identification and uploading the smartphone “slide” into the iNaturalist app.
Scientists and others using the app verify the accuracy of the field ID. When a certain amount of data is collected, any misidentified specimens become small enough in the overall data pool to become statistically insignificant and the data becomes a solid research tool.
Data collected to date can be found at inaturalist.org/projects/cyanoscope.
Code enforcement, local volunteers provide first defense
Local volunteers play another crucial role.
Even as the research moves forward, funding permitting, volunteers recreating in boats provide a first defense: documenting reckless development and reporting it to local code enforcement officers charged with upholding the Maine’s mandatory shoreland zoning ordinance.
In 1971, the Maine Shoreland Zoning Act established that municipalities had to create local ordinances that met or exceeded the state standard. Basically it prevents landowners from digging up the ground close to shore and whacking down all the shoreline trees and shrubs that act as important filters to keep soil, phosphorous, nitrogen and other pollutants from running off into lakes and replacing them with lawns.
Maine was way ahead of other states in protecting lakes, including Vermont, which only established standards in 2014.
According to the Maine DEP, shoreland zoning has been relatively effective in protecting shallow lakes. One of its weaknesses is enforcement, which falls to local officials and varies dramatically from place to place.
That is where active lake association volunteers working with local code enforcement officers and planning boards have made the difference between a clean lake and one prone to cyanobacteria blooms.
Volunteers play a dual role in some cases, working with landowners to provide information prior to development, and photo-documenting shorelines annually from a boat and alerting local officials if they see a shoreland zoning violation.
How NASA fits into ALS research
An important part of Torbick’s research is not from boats. It’s from satellites.
“The team uses NASA satellite remote sensing tools to measure and map lake water quality from space,” he said. It is work he hopes the National Institutes of Health (NIH) and NASA will continue to fund.
Under the White House budget, NIH faces a proposed 18-percent cut that will affect biomedical research funding, according to Kaiser Health News, and proposed cuts at NASA would blast a hole in the earth science research budget, according to E&E News.
So far, researchers have identified two ALS hot spots associated with cyanobacteria blooms and the presence of BMAA in Maine.
Torbick did not identify the exact locations — it’s too early in the research for that, he said — but they aren’t in high development areas, as one might expect.
They are Down East, in a part of the state known for agriculture.