Oxygen --- Identification of Water Pollution

"Do you know why do we need to measure the oxygen concentration in the water?"
"To test whether it is enough for the fish to breath?"

Ok that was a sample answer most probably will be given by normal people who are not into Chemistry or Water Science. The basic knowledge that we know about oxygen is, all living things need oxygen to breath and stay alive. From the perspective of Environmental Science, the oxygen concentration in the water means something more, and we call the oxygen 'dissolved oxygen' (DO). Oxygen is soluble in water, that's why aquatic life can breath underwater!

(image taken from Michael Prescotts's Blog)

Haze - Air Pollutant Index (API)

(screenshot taken from Air Pollutant Index of Malaysia)

The sun has been less scorching and the scenery has been blurry for almost a month. Holding an umbrella, I walked towards the faculty, trying my best to breath through nose despite of the burning smell, hopefully this amazing creation given by God can filter away the smoke suspending in the afternoon air during this hazy season. As a person with over 18 years of sinus experience, minimizing exposure towards the haze is a must to prevent triggering allergic condition but this trans-boundary man-made phenomenon has cornered many of us to the state that we have to stay in air-conditioned room whole day long, if it is available. Simply staying indoor to avoid the haze is no longer a temporary solution unless you shut off all the ventilation you have in the building. Haze has brought so much discomfort to our daily lives but how much do we actually know about the figure that we have been watching closely every day hoping for school closing to get information about the haze condition?