Science

Play it safe when cyanobacteria are present

Recently, I was a guest on VPR’s Vermont Edition, taking part in a discussion on the ecology and science of cyanobacteria (aka blue-green algae).  As always, there is never enough time to delve into the questions as deeply as I’d like to do.  So, today, I am going to dig a little deeper into a concern that was embedded in many of the questions posed by listeners – how do we enjoy our lakes, knowing that cyanobacteria live there?

Cyanobacteria are common around the world and native to Vermont.  They play an important role in the natural environment but can also sometimes produce toxins and compounds that cause illness to people, pets and livestock.  Because of this, algae conditions are monitored on selected Vermont lakes each summer and the data is shared with beach managers, water suppliers and lake visitors.

There are two important things to keep in mind when you read about the illnesses that may be caused by cyanobacteria:

  • if you don’t come in contact with them, there is low risk of illness; and
  • you can take precautions to minimize the opportunity for contact.

We manage risky situations on a daily basis in our lives.  The chances of being seriously injured or killed in a car accident are high, for example, but we don’t think twice about driving.  Instead, we reduce the risk of getting in an accident by requiring drivers training, following speed limits and rules of the road, and building better cars.  We regularly use a variety of chemicals in our homes, businesses and yards that may cause illness.  Paint thinners, pesticides for home use, and gasoline all carry warning labels reminding us these products are poisonous.  When we use them, we follow the label directions and take precautions to keep ourselves safe.

All lakes and ponds can be expected to have cyanobacteria, but most of the time these algae are not a problem in Vermont.  So, what should you do to keep yourself and your family safe on lakes that may have cyanobacteria?

A secchi disk viewed through a cyanobacterial bloom.  Play it safe - if the water is green and scummy like this, stay out

A secchi disk viewed through a cyanobacterial bloom. Play it safe – if the water is green and scummy like this, stay out

  • Learn to recognize cyanobacteria blooms and scums. Blooms and scums mean that there are lots of cyanobacteria present and that enough cyanobacteria toxins might be present to make you sick.
  • Keep people and pets away. Find another place to swim, kayak or walk the dog.  If it looks green and scummy, stay out.
  • If you think someone is ill because of cyanobacteria, get medical attention right away.
  • If you’re fishing and eat your catch, discard the skin and guts.
  • Shower off after swimming.
  • No one should be using untreated lake water in their home. Not all home water treatment systems are equal.  If you have a home water treatment system, check with your manufacturer to be sure that it can remove cyanobacteria toxins.

Vermont’s lakes, ponds and rivers offer dozens of places to get out on the water.  Just remember to check water and algae conditions so you can play safely.

For more information, visit the Watershed Management’s webpage on cyanobacteria.

Learn to recognize cyanobacteria so everyone can safely enjoy the water

Learn to recognize cyanobacteria so everyone can safely enjoy the water