Relative Humidity and Light Intensity Effects On Air Pollution

Presence of plants in an enclosed area or room results in elevated relative humidity which tends to remove air pollutants and improves air quality  by removing  irritating odors in heated environments.The dryness of the air have shown the symptoms of stress and eye irritation and increases the
impact of IAP. 

It has been reported that elevated levels of relative humidity may result in ii a beneficial effect on IAP. Low humidity showed lower respiratory and sick building symptoms and Humidification up to 33% to 44% om average showed improve thermal discomfort and air dryness effects and low levels of respirable particles and mold and bacteria content form 1 -6 microgram/m³   in hospital. The cooling effect of increased humidity will  cause a decrease in high temperature and reduction in symptoms.

Light Intensity also plays a key role in air purification efficiency as good light intensity depending upon plant species, enhances photosynthesis yield,, and thus contributes to air cleaning. In chlorella, the blue light of low intensity results in improved respiration.The blue light of low intensity (around 400 to 580 nm ) has shown improved photorespiration and photosynthesis rates in Spruce, wheat, soybean, oleander, and chard, and those plants unable to carry out photosynthesis are able to carry out. 

However, certain crop plants have shown decreased photosynthetic rates, transpiration, and stomatal activity resulting in less plant growth-producing small and thin leaves but vice versa in full sunlight conditions. Under increases light intensity the starch production increased and as Rubisco the main enzyme for CO₂ fixation rates decreases under shade and low-intensity conditions resulting in low yield and decreased photosynthesis, in many plants.

Shade whether under high or low conditions of light will are reported to decrease the chlorophyll fluorescence as it directly affects the PSII and results in blockage of electron transport chain from PSII to PSI and causes reduced leaf thickness length and height of plants. 

Therefore, plants used for air purification should be evergreen, high performance, and shade resistant under low intensity lights which are mostly found in modern air purification plants as they are tropical and subtropical plants able to survive shady and low intensity conditions.