Seawater is generally less likely to spread intestinal infections if accidentally swallowed than freshwater. However, seawater can pose risks to the skin through contact with open wounds, and certain bacteria present in marine waters can cause infections when they enter through cuts or mucous membranes. This information comes from a clinician at INVITRO-Ural who explains how sea conditions influence safety at the beach.
Several factors affect the chance of infection. Water temperature plays a big role since pathogenic microorganisms multiply slowly in cold water but can increase significantly when temperatures rise above about 24 degrees Celsius. More swimmers on a crowded beach raise the chance that someone might carry an infectious disease. Microbes are commonly found near the shore, and there is also a worry about contamination from sewer system failures. Infections can occur not only through ingesting contaminated water but also through skin contact, eye surface exposure, or microtrauma in the skin or mucous membranes.
Cases involving the ingestion of large volumes of salty seawater, particularly near drowning incidents or among individuals with certain health conditions, are of special concern. In such situations, immediate professional medical care is essential.
Sea water may have a temporary positive effect on the skin during bathing, but as water evaporates, salt crystals remain on the skin and can cause dryness or irritation. Prolonged sun exposure worsens these effects, so it is advised to rinse with fresh water after swimming and drying off to reduce irritation.
Optimal sea swimming conditions are typically when water temperatures are around 23 to 24 degrees Celsius. Temperatures below 18 degrees pose a real risk of hypothermia. A practical tip for beach days is to prefer morning swims before 11 a.m. and evening swims between 4 p.m. and 7 p.m., when the sun is less intense and the risk of heat-related issues is lower. If feeling cold, it is wise to exit the water and warm up rather than persist in the chilly water.
Beachgoers should assess local conditions before entering the sea. If there is a risk of sewage discharge, swimming should be avoided. Water color and clarity matter, and cloudy or unusually colored water with abundant coastal algae can indicate unsafe conditions. It is also prudent to avoid swimming if fresh, open wounds are present. For minor skin injuries, watching for signs of inflammation such as swelling or redness is important; if inflammation appears, treatment with antiseptics like hydrogen peroxide or chlorhexidine should be considered and medical help sought as needed. Early care is key to preventing complications. In some cases, sea bathing presents more danger than swimming in treated fountains, and individual health status should guide decisions about sea water exposure.