Agency officials say water samples Monday from Padre Island National Seashore, at Malaquite Beach, found moderate concentrations. Some people reported mild respiratory issues.
Red tide aerosols, kicked up through wave action, can cause breathing troubles in humans. The reddish bloom can kill fish and lead to shellfish poisoning in humans who consume it.
Agency officials say high to moderate concentrations of red tide were found in the lower Laguna Madre, along the beach front from Beach Access 6 to the Brazos Santiago jetties. Moderate concentrations were at the Isla Blanca Park boat ramp.