Why is sea water unfit for drinking use?

Sea water is unfit for drinking use primarily due to its high salt content. The average salinity of seawater is approximately 35 parts per thousand (ppt), meaning that for every kilogram of seawater, there are 35 grams of dissolved salts. The human body cannot process this amount of salt effectively, and consuming seawater can lead to several adverse health effects.

1. Dehydration: The high salt concentration in seawater causes the body to lose more water than it takes in. This can lead to dehydration, which can manifest through symptoms such as thirst, fatigue, dizziness, and headaches. Severe dehydration can be life-threatening.

2. Mineral Imbalance: Seawater contains various minerals, including sodium, chloride, magnesium, and sulfate, in different proportions compared to the human body's requirements. Consuming seawater can disrupt the body's mineral balance, potentially leading to health problems. For example, excessive sodium intake can raise blood pressure and increase the risk of cardiovascular diseases.

3. Digestive Issues: The high salt content in seawater can irritate the digestive tract, causing nausea, vomiting, and diarrhea. These symptoms can further contribute to dehydration and electrolyte imbalances.

4. Kidney Damage: Consuming seawater puts extra stress on the kidneys, as they have to work harder to filter out the excess salt and other minerals. Over time, this can lead to kidney damage and decreased kidney function.

5. Hypernatremia: In extreme cases, excessive consumption of seawater can lead to hypernatremia, a condition where the sodium levels in the blood become dangerously high. This condition can cause neurological symptoms such as confusion, seizures, coma, and even death.

Therefore, due to its high salt content and potential adverse health effects, seawater should not be considered a suitable source of drinking water. It is important to have access to clean and safe drinking water sources to maintain good health and prevent dehydration and other health complications.