Summer may seem carefree, but it’s no time for pooch parents to let down their guard. That’s when dogs are most at risk of so-called blue-green algae poisoning.

The culprit is actually a toxin-producing cyanobacteria [sigh-an-oh-back-TEAR-ee-ah] that can be found in ponds, lakes and slow-moving rivers. Exposure to the most serious of these toxins can cause liver or neurologic damage and since there’s no antidote, cyanobacterial toxicity can rapidly be fatal. If a poisoned dog makes it to a veterinary clinic, her survival depends on intensive care.

Tell-tale blue-green algal blooms develop in stagnant water, especially during warm dry periods. If you think your dog has been exposed, rinse him with fresh water and bring him to a veterinary hospital right away.