Blue-green algae warning issued
The Department of Health and Human Services (DHHS) cautions recreational users of local lagoons and rivers to be on the lookout for blue-green algae, which can be hazardous to dogs and humans.
Since 2001, 11 dogs are believed to have been killed by blue-green algae, which is common this time of year in warm, stagnant water. The dogs died shortly after swimming in affected areas of Big Lagoon and the South Fork Eel and Van Duzen rivers.
A nerve toxin associated with blue-green algae was found in the stomachs of the dogs that died on the South Fork Eel River in 2002. The same toxin was found in water samples from the South Fork Eel and Van Duzen rivers in 2009 shortly after two dogs died. Blue-green algae blooms that produce a liver toxin have been documented in Klamath River reservoirs and the Klamath River this year.
Dogs are more vulnerable than people to the effects of blue-green algae because they can swallow the algae when they lick their fur. Dogs have died within 30 minutes to one hour after leaving the water.
Blue-green algae looks like green, blue-green, white or brown scum, foam or mats floating on the water. These floating algal masses, or “blooms,” can produce natural toxins that are potent. Dogs and children are most likely to be affected because of their smaller body size and tendency to stay in the water for longer periods.
Potential symptoms in dogs following exposure to blue-green algae toxins can include lethargy, difficulty breathing, salivation, vomiting, urination, diarrhea or convulsions. People can experience eye irritation, skin rash, mouth ulcers, vomiting, diarrhea and cold or flu-like symptoms.
DHHS officials recommend the following guidelines for swimmers and boaters in all freshwater areas in Humboldt County:
• Keep children, pets and livestock from swimming in or drinking water containing algal scums or mats.
• Adults should also avoid wading and swimming in water containing algal blooms. Try not to swallow or inhale water spray in an algal bloom area.
• If no algal scums or mats are visible, you should still carefully watch young children and warn them not to swallow any water.
• Fish should be consumed only after removing the guts and liver and rinsing fillets in tap water.
• Never drink, cook with or wash dishes with water from rivers, streams or lakes.
• Get medical attention immediately if you think that you, your pet or livestock might have been poisoned by blue-green algae toxins. Be sure to tell the doctor about possible contact with blue-green algae.
Human activities can dramatically affect nutrient and water flows in rivers, streams or lakes. Phosphorous and nitrogen found in fertilizers and animal and human waste can stimulate blooms. Water diversions can increase water temperatures and reduce flows.
People can take the following measures to reduce the occurrence of algal blooms in local waters:
• Be conservative with the use of water, fertilizers and pesticides on your lawn, garden or agricultural operation.
• Recycle any “spent” soil that has been used for intensive growing by tilling it back into gardens or protect it from rainfall to avoid nutrient runoff.
• Plant or maintain native plants around banks. These plants help filter water and don’t require fertilizers.
• Pump and maintain your septic system every three to four years.
• Prevent surface water runoff from agricultural and livestock areas.
• Prevent erosion around construction and logging operations.
For more information, contact the DHHS Division of Environmental Health at
(707) 445-6215 or 1-800-963-9241. The California Department of Public Health website also has more details at http://www.cdph.ca.gov/healthinfo/environhealth/water/Pages/bluegreenalgae.aspx.