Over the years, the haze has become a normal part of people's lives, many cities across the country but still shrouded in haze. Various rumors about the haze have also emerged.
Myth 1: Is it fog or haze?
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The situation when fog. Fog is a product of water vapor condensation and is composed mainly of water vapor.
And blue skies and white clouds seen with the naked eye do not mean high air quality. Always look at the PM2.5 concentration.
Truth: Liu Zhiquan, deputy director of the Science and Technology Department of the Ministry of Environmental Protection, said, "This conclusion lacks the actual proof of a large number of samples, and the claim is not well-founded and controversial." He said that to conclude that soot pollution affects life expectancy, a large number of samples need to be obtained, and only after long-term observation and full scientific proof can a conclusion be reached. Although coal combustion can emit heavy metals, fine particles, sulfur dioxide and nitrogen oxides, etc., and these pollutants can have an impact on human health, there is no sufficient evidence on whether it affects human life expectancy and there is international controversy on the issue.
Zhu Yifang, deputy director of the Center for Clean Air at the University of California, Los Angeles, said the significant impact of air pollution on public health is indisputable, but life expectancy is affected by a combination of factors, but the findings of this study are to remove all other factors and only consider the life expectancy under the influence of a single factor: the total suspended particulate matter (TSP) in the air. In fact, according to the 2010 Global Burden of Disease Study, the number one cause of life expectancy loss in China is poor diet, followed by high blood pressure, smoking, and air pollution.
Myth 2: Haze causes lung cancer?
One, there is no direct evidence that haze causes lung cancer
The reason why people are controversial about the relationship between haze and cancer is because of the lack of direct evidence. Because so far, there is no direct research evidence to prove that the haze in China over the years has increased the incidence of lung cancer among Chinese people.
1. There is a lack of a perfect control group for the study.
2. Time span of influencing factors
The effect of haze or any environmental pollution on cancer must be chronic and long term, and it is impossible to see immediate results. If the increase in lung cancer in China in recent years is thought to be caused by environmental factors, it should be traced back to 10-20 years ago to see what kind of environmental pollution actually occurred in China at that time. It is not surprising that we do not have direct evidence that haze causes cancer, because this evidence exists in the future and has not yet appeared. For these two reasons, it is impossible for the scientific community to prove that the haze that now hangs over China can cause lung cancer.
While the scientific community can't directly prove whether the current haze can cause lung cancer, that's largely due to the limitations of time and research tools, and doesn't mean we can't analyze whether the haze can be a carcinogen. As early as the end of 2013, the International Agency for Research on Cancer (IARC) under the World Health Organization (WHO) came to the conclusion that "air pollution is carcinogenic" after collating more than 1,000 relevant research reports from five continents, and at the same time explicitly listed airborne particulate matter (including PM2.5) as a definite carcinogen. This is equivalent to saying that there is enough evidence to show that air pollution and cancer (lung cancer) have a direct causal relationship. And haze is a disease-causing, carcinogenic, medically speaking, there are two major reasons:
1. The haze contains carcinogenic chemicals
The haze or PM2.5 in the composition is very complex, the haze composition is different from place to place, but they all include hundreds of various types of chemical substances. Long-term inhalation of large amounts of these compounds can lead to genetic mutations that increase the chance of lung cancer.
2. Fine particles in the haze can cause long-term chronic lung damage
In the case of heavy air pollution, even if carcinogens are not taken into account, the inhalation of a variety of physical particles and chemicals can cause lung cell damage, and in order to repair this damage, lung cells need to divide and proliferate. Therefore, long-term air pollution will cause repeated cycles of "damage-repair-damage-repair" in the lungs, leading to a large number of cell divisions, thus increasing the probability of lung cancer. Simply put, air pollution leads to accelerated aging of the lungs, and lung cancer is one of the most dangerous consequences of lung aging. The more haze particles you inhale, the greater the impact on your body. Children, who are outdoors and unprotected, breathe deeper and more frequently, and are therefore definitely the biggest group of victims. Similarly, adults do not do protection in the haze long-distance running, square dancing and other sports, is also unwise.