6. References

Journal:

1. “The strive towards whiter paper has led to more bleaching and a substantial increase of the
concentration of fluorescent whitening agents (FWA) and violet-blue shading dyes added in paper.
FWA are dyes that absorb ultraviolet (UV) light”

A. Gustafsson Coppel, L. (2010). Perception and Optical Modelling. Whiteness and Fluorescence in Paper,
30.

2. “Concentrations of ammonia and nitrite exhibited the same variations in the grass carp fed with
sudangrass (D) and those fed with commercial feeds (E). Ammonia and nitrite concentrations were
higher in Ponds E than those in Ponds D”

B. Qin, Y. (2016, Oct 19). “Bacterial abundance and diversity in pond water supplied with different feeds”.

Website:

A. Light Sources (2015). “Killing Bacteria With UV Light”. Light Sources.

1. “This quality makes UVC energy an effective, environment-friendly and chemical-free
approach to killing dangerous microorganisms in any condition”

B. Phonesoap(August 10, 2018). “How Does UV Light Kill Bacteria?”. Phonesoap

2. “There are three different types of UV rays, and there's a common misconception that they
all do the same thing. While they are similar, each type of ray has a different wavelength and
can penetrate surfaces to a certain extent.

UV-A has the longest wavelength of 320-400 nm and is responsible for 95% of the UV radiation
that reaches the Earth's surface. These rays penetrate deep into the skin and are a factor in
premature aging.

UV-B is likely the UV ray you are most familiar with, as it is what will give you sunburns and
possibly skin cancer (shameless plug for sunscreen!)! This ray has a wavelength of 280-320
nm. “

C. Skin Vision. (August 11, 2017). “UV Rays - What are they and why are they dangerous”. Skin Vision.

3. “Shortwave (UV-C) radiation has a potent germ-killing effect” and “UVC wavelengths are in
between 200 and 300 nanometers, making them germicidal – meaning they are fit for
inactivating microorganisms, for example, bacteria, viruses, and protozoa”

D. USwatersystems. (August 11, 2017). “How Does UV Light Kill Bacteria?”. USwatersystems.

4. “UV or ultraviolet light is a type of radiation. In simple terms, when bacteria or another
type of microbe is directly exposed to certain types of UV light, the DNA (its fundamental
building block) of the cell is damaged, preventing it from replicating. If a cell cannot
reproduce, then the cell cannot cause infection, which is how UV light kills bacteria.

The UV process is a physical process as opposed to the addition of chlorine to the water
to address microbiological issues which is a chemical process. This is important,
because it allows UV to kill bacteria and other microorganisms without adding anything
to the water or creating what is known as disinfection by-products (like trihalomethanes,
called THMs for short, which are proven to be carcinogenic).”

E. Wikipedia.“Ultraviolet germicidal irradiation”. Wikipedia.

5. “UV causes the formation of lethal thymine dimers on bacterial DNA. It has been
demonstrated that UV is effective in killing microorganisms contaminating the surfaces
of a variety of materials. Thus the number of bacteria would reduce as the duration of the
bacteria under the UV light increases. Ultraviolet (UV) light is a type of light, invisible to the
human eye, that exists on the electromagnetic spectrum between X-beams and visible light and
which travels in a vacuum with the same speed of light equal to c. We are presented with low levels
of UV light from the sun’s beams each day, although the ozone layer consumes a significant part of
the UV energy. The UV light has three different bands depending on the wavelength; the UV-A,
UV-B and UV-C light spectrums. This spectrum differs in their wavelengths.“

News:

1. “Dark or bright colors, including red, black and navy blue, absorb more UV rays than
lighter colors like whites and pastels”

A. Venosa, A. (2017, August 11). “Dress to Protect: 5 Things that Affect How Well Your Clothes
Block UV Rays”. Sun Skin News/SkinCancer.