From Rappler by Pia Ranada
EMB of DENR, using PM (particulate matter ) 10 as a gauge (as mandated by Clean Air Act) for the said agency to monitor was up 3x compared to the same period last year. While this did not look very visible, it is indeed alarming. WHO monitors the PM 2.5, the much smaller particles, (they can enter the lungs, alveoli and the cardiovascular system causing not only respiratory disease but also cardio vascular diseases) We have to amend the law so that DENR employs the new and more relevant health related monitoring. We were fortunate though the sun shone brightly the following day, and there was light breeze, so the pollutants might have been blown over the ocean (where they could precipitate typhoons, and we did have typhoons lately hahaha)
EMB repo.rt of 2010 shows good air quality. It is now 2014. Are the reports updated?
MM air could be cancerous due to Polycyclic Aromatic Hydrocarbon (PAH) PDI July 16 2013
Let us quote the content of the post:
"Polycyclic aromatic hydrocarbons (PAHs) are cancer-causing pollutants that are released by the combustion process in motor vehicles.
The high temperature and high pressure conditions inside vehicle engines are conducive to the production of PAHs. Some of them attach to dust particles and are usually safely captured by physical filters of our respiratory system. However, the rest stay in gaseous form and in very small particles and are able to reach the lungs, easily breaching the hairy nasal filters. Eventually, they also reach the circulatory system as well, through the alveoli of the lungs.
Destroying DNA structure
Why should we be concerned with PAHs?
Many studies have shown that PAHs such as Benz(a)anthracene, Benzo(b)fluoranthene, Dimethylbenzanthracene, Benzo(a)pyrene, Indeno(1,2,3–cd) pyrene and Dibenz(a,h)anthracene produce cancer in animals.
These PAHs form metabolites in the body that can directly destroy the normal structure of DNA and subsequently cause the formation of abnormal proteins and cancerous tumors.
In humans, these PAHs are considered most probable carcinogens based on the evidence of carcinogenicity in animals, and the probability that similarity in metabolic processes involved in dealing with PAHs exists in humans and animals.
The current assessment of the health significance of exposure to PAHs determines the health risk of exposure to the traditionally used marker substance Benzo(a)pyrene.
Studies by the World Health Organization show that there is a probability of one in 10,000 that a person will have cancer if he is exposed to ambient air with 1 nanogram (ng)/m3 Benzo(a)pyrene during his lifetime.
The relationship of exposure to PAHs and genetic damage in breast tissues and breast cancer was investigated by Frederica Perera and her group from Mailman School of Public Health in New York.
In a paper published in Carcinogenesis in 2000, the researchers found that the higher levels of DNA-PAH adducts in breast cancer tissues, reflecting that individual exposure and susceptibility to PAH may play a role in breast cancer. The possible modes of action of PAHs in breast cancer were investigated by Martina Pliskova and her group from the Veterinary Research Institute in the Czech Republic.
In their paper published in Toxicological Sciences in 2004, metabolites of Benzo(a)pyrene, and Benzo(a)anthracene were found to induce cell proliferation of breast cancer cells, both by activation of the estrogen receptor that expresses cell proliferation, and by causing genetic damage to the DNA damage repair checkpoints that eventually result in the proliferation of DNA-damaged cells.
In a 2001 survey of PAHs in ambient air particulates conducted by this author in four sites along the stretch of Epifanio de los Santos Avenue (Edsa), in two industrial sites and in three residential areas within Metro Manila, the concentrations of Benzo(a)pyrene (1.2-10.6 ng/m3) detected in all the sampling sites exceeded 1 ng/m3; this indicates that lifetime exposure to ambient air at most of the study sites could pose higher risk of more than one in 10,000 to cancer.
The additional potential toxicity from three other carcinogenic PAHs detected in these sites further increases the risk of the exposed population to cancer.
This was circa 2001 and 2009; it is now 2004. It could be worse.
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