Latest news with #cyanobacteria
Yahoo
5 days ago
- Health
- Yahoo
Toxic algae blooms are lasting longer in Lake Erie − why that's a worry for people and pets
Lake Erie algal blooms, August 2011, along the southeast Lake Erie shore of Pelee Island, Ontario, Canada, 5 miles north of the international line. | Michigan Sea Grant Gregory J. Dick, University of Michigan Federal scientists released their annual forecast for Lake Erie's harmful algal blooms on June 26, 2025, and they expect a mild to moderate season. However, anyone who comes in contact with the blooms can face health risks, and it's worth remembering that 2014, when toxins from algae blooms contaminated the water supply in Toledo, Ohio, was considered a moderate year, too. The Conversation asked Gregory J. Dick, who leads the Cooperative Institute for Great Lakes Research, a federally funded center at the University of Michigan that studies harmful algal blooms among other Great Lakes issues, why they're such a concern. bulletin_current 1. What causes harmful algal blooms? Harmful algal blooms are dense patches of excessive algae growth that can occur in any type of water body, including ponds, reservoirs, rivers, lakes and oceans. When you see them in freshwater, you're typically seeing cyanobacteria, also known as blue-green algae. These photosynthetic bacteria have inhabited our planet for billions of years. In fact, they were responsible for oxygenating Earth's atmosphere, which enabled plant and animal life as we know it. Algae are natural components of ecosystems, but they cause trouble when they proliferate to high densities, creating what we call blooms. Harmful algal blooms form scums at the water surface and produce toxins that can harm ecosystems, water quality and human health. They have been reported in all 50 U.S. states, all five Great Lakes and nearly every country around the world. Blue-green algae blooms are becoming more common in inland waters. The main sources of harmful algal blooms are excess nutrients in the water, typically phosphorus and nitrogen. Historically, these excess nutrients mainly came from sewage and phosphorus-based detergents used in laundry machines and dishwashers that ended up in waterways. U.S. environmental laws in the early 1970s addressed this by requiring sewage treatment and banning phosphorus detergents, with spectacular success. Today, agriculture is the main source of excess nutrients from chemical fertilizer or manure applied to farm fields to grow crops. Rainstorms wash these nutrients into streams and rivers that deliver them to lakes and coastal areas, where they fertilize algal blooms. In the U.S., most of these nutrients come from industrial-scale corn production, which is largely used as animal feed or to produce ethanol for gasoline. Climate change also exacerbates the problem in two ways. First, cyanobacteria grow faster at higher temperatures. Second, climate-driven increases in precipitation, especially large storms, cause more nutrient runoff that has led to record-setting blooms. 2. What does your team's DNA testing tell us about Lake Erie's harmful algal blooms? Harmful algal blooms contain a mixture of cyanobacterial species that can produce an array of different toxins, many of which are still being discovered. When my colleagues and I recently sequenced DNA from Lake Erie water, we found new types of microcystins, the notorious toxins that were responsible for contaminating Toledo's drinking water supply in 2014. These novel molecules cannot be detected with traditional methods and show some signs of causing toxicity, though further studies are needed to confirm their human health effects. We also found organisms responsible for producing saxitoxin, a potent neurotoxin that is well known for causing paralytic shellfish poisoning on the Pacific Coast of North America and elsewhere. Saxitoxins have been detected at low concentrations in the Great Lakes for some time, but the recent discovery of hot spots of genes that make the toxin makes them an emerging concern. Our research suggests warmer water temperatures could boost its production, which raises concerns that saxitoxin will become more prevalent with climate change. However, the controls on toxin production are complex, and more research is needed to test this hypothesis. Federal monitoring programs are essential for tracking and understanding emerging threats. 3. Should people worry about these blooms? Harmful algal blooms are unsightly and smelly, making them a concern for recreation, property values and businesses. They can disrupt food webs and harm aquatic life, though a recent study suggested that their effects on the Lake Erie food web so far are not substantial. But the biggest impact is from the toxins these algae produce that are harmful to humans and lethal to pets. The toxins can cause acute health problems such as gastrointestinal symptoms, headache, fever and skin irritation. Dogs can die from ingesting lake water with harmful algal blooms. Emerging science suggests that long-term exposure to harmful algal blooms, for example over months or years, can cause or exacerbate chronic respiratory, cardiovascular and gastrointestinal problems and may be linked to liver cancers, kidney disease and neurological issues. In addition to exposure through direct ingestion or skin contact, recent research also indicates that inhaling toxins that get into the air may harm health, raising concerns for coastal residents and boaters, but more research is needed to understand the risks. The Toledo drinking water crisis of 2014 illustrated the vast potential for algal blooms to cause harm in the Great Lakes. Toxins infiltrated the drinking water system and were detected in processed municipal water, resulting in a three-day 'do not drink' advisory. The episode affected residents, hospitals and businesses, and it ultimately cost the city an estimated US$65 million. 4. Blooms seem to be starting earlier in the year and lasting longer – why is that happening? Warmer waters are extending the duration of the blooms. In 2025, NOAA detected these toxins in Lake Erie on April 28, earlier than ever before. The 2022 bloom in Lake Erie persisted into November, which is rare if not unprecedented. Scientific studies of western Lake Erie show that the potential cyanobacterial growth rate has increased by up to 30% and the length of the bloom season has expanded by up to a month from 1995 to 2022, especially in warmer, shallow waters. These results are consistent with our understanding of cyanobacterial physiology: Blooms like it hot – cyanobacteria grow faster at higher temperatures. 5. What can be done to reduce the likelihood of algal blooms in the future? The best and perhaps only hope of reducing the size and occurrence of harmful algal blooms is to reduce the amount of nutrients reaching the Great Lakes. In Lake Erie, where nutrients come primarily from agriculture, that means improving agricultural practices and restoring wetlands to reduce the amount of nutrients flowing off of farm fields and into the lake. Early indications suggest that Ohio's H2Ohio program, which works with farmers to reduce runoff, is making some gains in this regard, but future funding for H2Ohio is uncertain. In places like Lake Superior, where harmful algal blooms appear to be driven by climate change, the solution likely requires halting and reversing the rapid human-driven increase in greenhouse gases in the atmosphere. Gregory J. Dick, Professor of Biology, University of Michigan This article is republished from The Conversation under a Creative Commons license. Read the original article.
CTV News
5 days ago
- Health
- CTV News
Blue-green algae advisory issued for Isle Lake
Samples from a bloom of blue-green algae taken from the French River have been confirmed to be a species of cyanobacteria that can produce toxins. (File) Visitors to Isle Lake should watch out for blue-green algae. Alberta Health Services (AHS) issued a release Friday saying cyanobacteria had been found in the lake that spans the Parkland and Lac Ste. Anne Counties. The algae, which can appear like scum, grass clippings or fuzz on water's surface, can be harmful to people and animals that come into contact with it. Symptoms include skin irritation, rash, sore throat and eyes, fever, nausea, vomiting and diarrhea. People and pets should not swim or wade where algae is present or eat whole fish or fish trimmings from the lake, AHS said, but fish filets are safe. Any area of the lake where the bacteria are not present is safe to use. AHS said untreated water from any body of water should never be used for drinking or cooking. For more information, visit the AHS website. Anyone who suspects illness related to cyanobacteria can also call Health Link at 811.
CTV News
6 days ago
- Health
- CTV News
Mild to moderately harmful algae blooms predicted in Lake Erie
Ohio federal researchers predict that this year's algae blooms in Lake Erie will be mild to moderately harmful. The National Oceanic and Atmospheric Administration forecasts the bloom to measure around three on the Harmful Algal Bloom Severity Index on a scale of one to 10, 10 being the most severe. A three means possible impacts on drinking water, public health, and tourism. The blooms are made up of cyanobacteria, which is also called blue-green algae. It can produce a toxin that's dangerous for people and animals. Officials with the Great Lakes Institute for Environmental Research at the University of Windsor said no matter the size of the bloom, we can't let our guard down, as the risk is always present. 'Even though we're talking about Lake Erie right now, this is the same advice that applies to Lake St. Clair, where we're more likely to see blooms along the Ontario shoreline,' said Mike McKay, Glier director with UWindsor. 'Avoid green water. It may not be toxic, but it's not worth taking the chance.'
The Independent
19-06-2025
- Health
- The Independent
Why Americans who live near coastlines and lakefronts may face heightened ALS risk
If you live near bodies of water frequently impacted by harmful algal blooms, you may be at an increased risk of dying from ALS, new research reveals. Amyotrophic lateral sclerosis, the debilitating neurodegenerative disease commonly known as 'Lou Gehrig's Disease,' is influenced by genetics and environmental factors. It dramatically slashes the patient's life expectancy, with people typically passing away within two to five years of diagnosis. Some 5,000 are diagnosed with ALS each year in the U.S. Now, researchers at the University of Michigan Medicine say toxins produced by algal blooms in lakes and along American coasts could influence disease progression. 'While there is still limited research into the mechanism by which cyanobacteria toxins affect neurodegenerative diseases, our findings suggest that living near or participating in activities in these water bodies may influence the progression of ALS,' Dr. Stephen Goutman, the school's Harriet Hiller research professor, director of the Pranger ALS Clinic, and associate director of the ALS Center of Excellence, said in a statement. Goutman is the senior author of the study which was published in the International Journal of Environmental Research and Public Health. Specifically, the researchers have found a toxin produced by the bloom cyanobacteria in brain and spinal fluid cerebral spinal fluid samples of people with ALS. It's known as ß-methylamino-L-alanine. Increasingly driven by human-caused climate change and nutrient pollution, the blooms are caused when cyanobacteria grows dense and out of control. Cyanobacteria produce several toxic agents that are linked neurodegenerative diseases, including Alzheimer's and Parkinson's. They surveyed participants who were seen at the University of Michigan Pranger ALS Clinic, many of whom lived within three miles of a harmful algal bloom. They measured the duration and extent of their exposure using satellite data from the Cyanobacteria Assessment Network and their residential and health histories. Ultimately, they found that living near blooms -- especially if swimming or boating -- was associated with dying of ALS nearly one year sooner. The people with the most significant exposures both lived near harmful blooms and used a private well as their water source. People in the Midwest may be particularly threatened partially due to pervasive industrial and agricultural productions in the region. Michigan's Lake Erie is frequently impacted by these blooms. 'If exposure to cyanobacteria toxins is a meaningful risk factor for ALS, the large number of inland lakes from to such bacteria in the Midwest may partly explain why the disease incidence is much higher than other parts of the country,' Dr. Stuart Batterman, first author and professor of environmental health sciences at the university's School of Public Health, said.
CTV News
18-06-2025
- Health
- CTV News
AHS warns of blue-green algae at Elk Island
Alberta Health Services (AHS) is warning visitors to Elk Island National Park of blue-green algae seen in the waters of Astotin Lake. The health authority said to avoid all contact with blue-green algae blooms and to wash with tap water as soon as possible if contact occurs. Do not swim or allow pets to swim or wade in areas where the algae is visible. Consider limiting human consumption of whole fish or fish trimmings from the lake. Do not feed any fish or fish trimmings to pets. Fish filets from the lake are safe for humans to eat. Blue-green algae, also known as cyanobacteria, can look like scum, grass clippings, fuzz or globs on the surface water. It can be blue-green, greenish-brown, brown and/or pinkish-red, and often smell musty or grassy. Blue-green algae Blue-green algae is seen near the shore in this undated photo. (Courtesy: Grand River Conservation Authority/ Skin irritation, rash, sore throat, sore red eyes, swollen lips, fever, nausea and vomiting and/or diarrhea can occur when exposed to blue-green algae or by consuming water containing the bacteria. Exposure to blue-green algae can cause death to pets. Waters of Astotin Lake that do not have visible blue-green algae can still be used for recreational purposes.
