Chapter 2: Research on the Negative Effects of Radiation in Davao City

 

Chapter 2

REVIEW OF RELATED LITERATURE

            Presented in this chapter is a review of related literature and some studies on the effects of radiation on people's health and the environment.  This serves as background information in determining the negative or ill effects of radiation on people's health and on the environment as well.

 

Related Literature and Studies

Negative Effects of Radiation on People’s Health

Negative Effects of Computer Radiation.  Computer radiation, laptop radiation and computer monitor radiation are important for all computer users.  This type of radiation is known as extremely low frequency (ELF) electromagnetic radiation. It is essentially the same kind of radiation that is emitted from power lines, TVs and other electrical and electronic appliances.  If you are a computer user, computer radiation may be a substantial component of the total electromagnetic radiation which your body is exposed to. Many of us spend our working days in front of computer monitors, surrounded by electronic equipment, each item emitting ELF radiation. Because of the duration of this exposure (many hours every day), computer radiation is a great concern.

            The "Encyclopedia Britannica" reports that "prolonged exposure to computer radiation leads to an increased risk of tumors, cancers, miscarriage, blood disorders, insomnia, headaches, anxiety, and skin disorders."  Many people spend hours in front of computers that emit low levels of radiation. Such exposure is not considered harmful, although prolonged exposure is a matter of concern, according to some authorities. Some studies report that prolonged use of laptops by men can affect infertility.  Warmth and radiation may affect the quality and quantity of sperm production.

            For many years it has been known that ELF radiation can cause or contribute to various health problems, ranging from sleep interference and allergic reactions, through to heart disease, cancer and Alzheimer's disease. The item most likely to cause a health hazard in many offices is the computer monitor, or screen. The box-shaped cathode ray tube (CRT) computer monitors generally have quite high levels of radiation at 30 cm.   A constant 3 milligausus at 30 cm of computer monitor radiation is already bad enough, but don't forget the beleaguered computer user is probably also absorbing radiation from computers, printers, power supplies (ups), florescent lights, cell phones and other equipment.  Pregnant women should be particularly careful about using CRT screens - which have been associated with higher rates of miscarriage and possibly birth defects.

Negative Effects of Mobile Phone Radiation.  Mobile phone radiation and health effects have been studied, especially following the enormous increase in the use of wireless mobile telephony throughout the world, there were more than 4 billion users worldwide.  Mobile phones use electromagnetic radiation in the microwave range, and researchers believe this may be either harmful or beneficial to human health.  A Swedish scientific team at the Karolinska Institute conducted an epidemiological study (2004) that suggested that regular use of a mobile phone over a decade or more was associated with an increased risk of acoustic neuroma, a type of benign brain tumor. The increase was not noted in those who had used phones for fewer than 10 years.

            Hardell (2007) reviewed published epidemiological papers (2 cohort studies and 16 case-control studies) and found that:  Cell phone users had an increased risk of malignant gliomas. There has been a link between cell phone use and a higher rate of acoustic neuromas.  Tumors are more likely to occur on the side of the head that the cell handset is used. One hour of cell phone use per day significantly increases tumor risk after ten years or more.

            Some users of mobile handsets have reported feeling several unspecific symptoms during and after its use; ranging from burning and tingling sensations in the skin of the head and extremities, fatigue, sleep disturbances, dizziness, loss of mental attention, reaction times and memory retentiveness, headaches, malaise, tachycardia (heart palpitations), to disturbances of the digestive system.

            Negative Effects of Radiation from Wireless Networks.  Another area of concern is the radiation emitted by the fixed infrastructure used in mobile telephony, such as base stations and their antennas, which provide the link to and from mobile phones. This is because, in contrast to mobile handsets, it is emitted continuously and is more powerful at close quarters. On the other hand, field intensities drop rapidly with distance away from the base of the antenna because of the attenuation of power with the square of distance. Base station emissions must comply with safety guidelines. Some countries, however (such as South Africa) do not have any health regulations at all governing the placement of base stations.  

        Since the middle of the last century, technological advancements in telecommunications and other industries have led to significant increases in the use of radio frequencies. Equipment employing microwave and radio waves is today widely used not just in broadcasting and communications, but also in the health care industry, the food industry, and in a host of other industries in a wide range of applications. Several surveys have found increases of symptoms depending upon proximity to electromagnetic sources such as mobile phone base stations.

            A 2002 survey study by Santini et al. in France found a variety of self-reported symptoms for people who reported that they were living within 300 metres (984 ft) of GSM cell towers in rural areas, or within 100 m (328 ft) of base stations in urban areas. Fatigue, headache, sleep disruption and loss of memory were among the symptoms reported.  Similar results have been obtained with GSM cell towers in Spain, Egypt Poland and Austria.  No major studies have been reported in which health effects did not occur on actual populations living near mobile base stations. However, there are significant challenges in conducting studies of populations near base stations, especially in assessment of individual exposure.

            In order to protect the population living around base stations and users of mobile handsets, governments and regulatory bodies adopt safety standards, which translate to limits on exposure levels below a certain value. There are many proposed national and international standards, but that of the International Commission for Non-Ionizing Radiation Protection (ICNIRP) is the most respected one, and has been adopted so far by more than 80 countries. For radio stations, ICNIRP proposes two safety levels: one for occupational exposure, another one for the general population. Currently there are efforts underway to harmonize the different standards in existence.

            Many governmental bodies also require that competing telecommunication companies try to achieve sharing of towers so as to decrease environmental and cosmetic impact. This issue is an influential factor of rejection of installation of new antennas and towers in communities.

Negative Effects of Radiation from X-ray Machines, TV Sets and Photocopiers.  Man cannot escape exposure to some radiation. We are surrounded by natural radioactivity in the earth and by cosmic rays from outer space. This is called background radiation and cannot be controlled. We are also exposed to manmade radiation, which can and must be controlled.

Much of the manmade radiation people are exposed to comes from electronic products. These include diagnostic x-ray machines, television sets, microwave ovens, radar devices, and lasers. In some cases, as with diagnostic x-rays, radiation emitted from these devices is intentional and serves a useful purpose. In others, as with TV sets, radiation emitted is not intentional and is not essential to the use of the product. X-rays may be produced when electrons, accelerated by high voltage, strike an obstacle while traveling in a vacuum, as in a TV containing a cathode ray tube (CRT). Since many of the components in television sets operate at thousands of volts, there is the potential for x-ray generation. These components may produce x-rays capable of escaping from the television receiver or CRT. This unintentional emission of x-radiation can pose a potential hazard and must be controlled.

            The U.S. Public Health Service opened an inquiry into the possible effects of radiation leakage from color television sets. One set manufacturer, General Electric, modified more than 100,000 sets to eliminate leakage. Surgeon General William H. Stewart minimized the danger to viewers. He suggested a viewing distance of six to ten feet from a color television set and warned against prolonged exposure to the rear or sides of a set.

            Negative Effects of Microwave Radiation.  According to CWA, “there is substantial scientific data that establishes negative health effects associated with microwave radiation.” CWA cites cataracts as one possible negative health effect from prolonged exposure, as well as well as nervous system damage and even reproductive problems in both males and females.  Exposure to microwaves is dangerous mainly when high densities of microwave radiation are involved, as with masers. They can cause burns, cataracts, damage to the nervous system, and sterility. The U.S. government limits the exposure level, in general, to 10 milliwatts per square centimeter. Stricter limits are placed on microwave ovens.

            Negative Effects of Ultraviolet Radiation.  Human exposure to solar ultraviolet radiation has important public health implications. Evidence of harm associated with overexposure to UV has been demonstrated in many studies.  Skin cancer and malignant melanoma are among the most severe health effects, but a series of other health effects have been identified. The current report provides a quantification of the global disease burden associated with UV. The information presented forms a knowledge base for the prevention of adverse effects of UV exposure that is achievable with known and accessible interventions. UV prevention focuses on protecting the skin and other organs from UV radiation. On the other hand, a moderate degree of UV exposure is necessary for the production of Vitamin D which is essential for bone health. Additionally, evidence emerges that low Vitamin D levels are likely to be associated with other chronic diseases. Thus, public health policy on ultraviolet radiation needs to aim at preventing the disease burden associated both with excessive and with insufficient UV exposure.

      Negative Effects of Radiation on the Environment.  Radiation occurs naturally when the nuclei of radioactive elements decay. Heat and light are forms of radiation that are generally not considered harmful. However, many forms of radiation, such as radiation which occurs in nuclear reactions, is deadly and can potentially cause long term environmental problems and damage. (Earle,2009)

            Radiation can have devastating effects on living plants and animals. Radiation can damage living things at a cellular and genetic level. In some cases, damaged cells can repair themselves, but in other cases the damage is irreparable. One type of irreparable damage is genetic. Radiation can damage a cell's DNA, thus triggering cellular mutation that can sometimes result in cancer.

            The environmental effects of radio frequencies are also largely unclear. Migrating birds have been known to fly right into cell phone and other communications towers. Some blame the radiation emanating from such towers for disorienting the birds and undermining their navigational abilities. Others chalk such incidents up to poor visibility associated with bad weather and nothing more. Some farmers have observed that cows grazing near cell towers are more likely to experience still births, spontaneous abortions, birth deformities and behavioral problems, not to mention general declines in overall health. Moving cattle herds away from such towers has reportedly led to immediate health improvements.

            Radiation can cause severe cellular damage in seeds which sometimes prevents them from sprouting and germinating, thus affecting the ability of plants to reproduce. In addition, radiation can cause genetic mutations in growing plants which can hurt their ability to survive.

            Radiation can trigger genetic changes in the cells of animals which result in the cells growing out of control. These out of control cell clusters are cancerous tumors. In addition, higher levels of radiation can cause damage to capillaries and small blood vessels, these higher levels can sometimes result in catastrophic heart failure or brain aneurysms. Because radiation is often accompanied by intense heat, which is simply a different type of radiation, exposure to intense radiation can often "cook" an animal. Some forms of radiation, such as microwave radiation, will cause animal life to "cook" from the inside out.

Research Hypothesis

The null hypothesis was formulated and tested that there is no significant difference in the level of awareness of the public on the ill effects of radiation when they are grouped by gender, age and educational attainment.

Ann Cervales, Philippines