[ (4) 2: 962-965 ] © 2018 IJSRST | Volume 4 | Issue 2 | Print ABSTRACT In 20 th century narrow spectrum incandescent electric light bulb and low pressure sodium (LPS) lamp has been widely used. But to improve efficiency and to cut carbon dioxide (CO2) emission this old narrow spectral light sources are replaced by broader spectrum light sources such has high pressure sodium (HPS) lamp, compact fluorescent lamp (CFL), light emitting diode (LED). CFLs and LEDs are more efficient and cut carbon

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... ssion in environment. These light sources save much more electric energy as compared to incandescent bulbs and provide to improve colour rendering capability for humans. Shifting broadening the spectra of artificial light (white light) may leads adverse effect on human health. Some CFLs emits a short wavelength (254nm) ultraviolet (UV) radiation that causes different skin diseases. Broken CFLs and compact light tubes emit mercury in air which is produce hazards effect on human health. LED at colour temperature (CT) 4000K to 5000K contain high level of short wavelength blue light that can cause damage to retina of human eye. High intense white light sources also produce problems seeing for safe driving and working at night. LED sources can suppress melatonin secretion which affects on circadian rhythms, sleep disorders, problem of obesity and thyroid. As this impact of broaden spectrum white light sources is concern there is need to make some policies and to develop a such artificial light which is energy efficient and make less harmful effect on human health and environment.