More People Drown in Freshwater than in Saltwater

Drowning involves suffocation while in water. Around 90% of drownings occur in freshwater, such as swimming pools, bath tubs and rivers, while only 10% of drownings occur in saltwater.

Drowning in freshwater is different
from drowning in saltwater.

Drowning in saltwater:
when u breathe in saltwater, high salt concentration prevents the water from crossing into lung tissues. Salt water is hypertonic to the ion concentration in lung cells, so water from bloodstream enters your lungs to compensate for the concentration gradient. Blood thickens, putting strain on circulatory system. The stress on heart can lead to cardiac arrest within 8 to 10 minutes.
By drinking water blood can be easily rehydrated. So you are well on the road of recovery if you can survive the initial experience.

Drowning in freshwater:

U can die from breathing freshwater. This is because freshwater is hypotonice compared with the fluid inside lung cells. Freshwater doesn't cross into skin cells because keratin essentially waterproofs them, but water rushes into unprotected lung cells to equalize the concentration gradient across cell membranes. This can cause massive tissue damage, so even if the water is recovered from your lungs, there is a chance u might not recover.
Fresh water is more dilute with respect to fluid inside lung cells.

When water enters cells, it swells them. Cells may burst. Lung capillaries are exposed to freshwater, water enters bloodstream. This dilutes blood. Blood cells burst (hemolysis). Elevated plasma K^+ (potassium ions) and depressed Na^+ (Sodium ions) levels may disrupt the heart's electrolytic activity causing ventricular fibrillation. Cardiac arrest occurs in as little as 2 to 3 minutes. Acute Renal Failure may also occure due to burst blood cells in kidneys.
Cardiac arrest may also occur from hypothermia..

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