April 17, 2024

Health Matters | Late summer is critical for watching out for algal blooms – Times-Standard

By Benjamin Dolf

Late summer offers some of the nicest weather here in Humboldt County. The Department of Health and Human Services, Division of Environmental Health wants to remind folks to be conscious when recreating in and around rivers, streams, lakes and estuaries. Diminishing flows and elevated water temperatures of late summer create opportunities for algal blooms — some of which can be harmful to people and even deadly to pets.

The term Harmful Algae Bloom (HAB) is used in reference to rapid reproduction of a wide variety of naturally occurring photosynthetic microorganisms with the potential for negative impacts to people, pets and the environment. Bloom events coincide with warm, slow-moving water conditions, common in late summer, and are intensified by added nutrients. In 2021, the Centers for Disease Control and Prevention reported 368 harmful algal bloom events resulting in 117 human illnesses and over 2,715 animal illnesses or deaths.

Cyanobacteria (sometimes called blue-green algae) are of particular concern. Under bloom conditions, these organisms can produce highly toxic compounds called cyanotoxins, that can cause neurological and/or gastrointestinal symptoms. Even when toxins aren’t present, cyanobacteria can adversely impact people and animals. Exposure to elevated amounts of cyanobacterial cells, which may appear as discolored water, scum or mats, has been associated with dermal effects such as rashes, ear and eye infections and gastrointestinal distress.

Practice safe water habits when recreating outdoors:

• Heed all instructions on posted advisories.

• Avoid algae and scum in the water and on shore.

• Keep an eye on children and pets (dogs).

• If you think an algal bloom is present, do not let pets and other animals go into or drink the water or eat scum and algal accumulations on the shore.

• If you think an algal bloom is present, reduce potential for inhalation of sprays or mists by avoiding areas downwind of the bloom and activities near the bloom that can kick up spray, such as boating at higher speeds, water skiing or splashing.

• Don’t drink the water or use it for cooking.

• Wash yourself, your family and your pets with clean water after water play.

• If you catch fish, throw away the guts and the clean fillets with tap water or bottled water before cooking.

• Avoid eating shellfish if you think a HAB is present.

The following symptoms may occur within 48 hours of exposure to a waterbody with a suspected or confirmed algal bloom:

•  Sore throat or congestion

• Coughing, wheezing or difficulty breathing

• Red, or itchy skin or a rash

• Skin blisters or hives

• Earache or irritated eyes

• Diarrhea or vomiting

• Agitation

• Headache

• Abdominal pain.

Dogs are particularly susceptible to cyanobacterial poisoning. Animals often drink the water, lick algae caught in their fur and even eat algal mats. Never let your dog drink, wade or swim in water that may show signs of an algal bloom, or eat algal material. It is recommended that pets get bathed after lake or river play. Animals can become sick within minutes to days after exposure to harmful algae. Contact your veterinarian if your animal shows any of these signs:

• Loss of energy

• Loss of appetite

• Vomiting

• Stumbling and falling

• Foaming at the mouth

• Diarrhea

• Convulsions

• Excessive drooling

• Tremors and seizures

• Dermal irritation or rash

• Any unexplained sickness that occurs within a day or so after being in contact with lake or river water.

If you suspect a water body is experiencing an algal bloom, or if you or your pet exhibit symptoms following water-related activities, contact the Humboldt County Division of Environmental Health at 707-445-6215 or at ENVHEALTH@co.humboldt.ca.us. For more information, visit https://mywaterquality.ca.gov/habs/where/freshwater_events.html.

Benjamin Dolf is a registered environmental health specialist with the Humboldt County Department of Health and Human Services Division of Environmental Health.


Leave a Reply

Your email address will not be published. Required fields are marked *