Smog is a health issue in many cities around the world. Some countries, however, are disproportionately plagued by the issue of pollution - China, for example, endures consistent reports of haze, dense particulate matter, and airborne industrial discharges. In fact, the World Bank reports that more than three quarters of the world's most polluted countries are found in China. So, what is China doing to keep its citizens safe from smog?
Quite a bit, actually. In recent years, the government has conducted research into the causes of pollution, and its effects on people and the environment. Encouraged by the international community, anti-pollution regulations have been put into place - many industrial practices and factories have been modernized, waste management regulations have been created, and simple legislation has been passed, such as charging shoppers for taking a plastic bag.
Just this week, another exciting anti-pollution measure was reported in Hebei, a province near Beijing famous for its steel industry. Officials in the capital city Shijiazhuang announced on Wednesday that the city would begin limiting car ownership in order to reduce air pollution. Using a lottery system similar to that in Beijing, the Shijiazhuang government will only allow the purchase 100,000 new vehicles this year. Households with two cars will also be prohibited from buying any more.
Other cities around China have begun instituting similar automobile legislation. Shanghai, Beijing, Guangzhou and Guiyang all have car quotas meant to reduce congestion on the roads, and cut smog overhead.
But, is such drastic action necessary? To what extent does air pollution actually affect our health?
Studies about health and smog are conducted quite regularly, and around the globe, researchers have come to very similar conclusions - that air pollution is absolutely detrimental to health, and in a number of different ways.
Recently, scientists have begun to consider the effects of pollution upon babies not yet born. In April of this year, a study from the Los Angeles School of Public Health at the University of California found that pregnant women exposed to high levels of traffic pollution may be more likely to give birth to children who will develop early childhood cancer. Researchers examined 3,600 children with cancer over nearly a decade, comparing them to similar children who had not been diagnosed with the disease. Findings showed that a mother's exposure to vehicular air pollution was associated with a cancer risk for her child of up to 15 percent more than normal. However, experts agree that more research is necessary to truly understand these results - there is some theorizing that it may be air particulate exposure during the first year of life, rather than exposure in utero, that results in this increased cancer risk.
Also in April of this year was the release of a report on smog, China, and premature deaths. Coming from the Health Effects Institute of Boston, this analysis noted that around 1.2 million people die in China, prematurely as a result of poor air quality. The Health Effects Institute found that Chinese citizens already weakened by a disease such as asthma were especially likely to become fatally ill due, at least in part, to the effects of harmful particulate matter. As other studies have shown, the very young and the very old were found to be especially vulnerable to a weaker immune system after extended exposure to air pollution.
Interestingly, some scientists are finding that smog hurts not just our bodies, but our minds as well. In a July 2012 article from the Monitor on Psychology , journalist Kirsten Weir explored the idea of air pollution leading to a loss in cognitive functioning. Entitled "Smog in our Brains," the article discusses recent evidence proving that exposure to fine particulate matter can cause cognitive decline in older women, and that black carbon (or soot) has been shown to affect older men in a similar manner. The effects of these pollutants upon the older brain may be equivalent to having aged two years in just a short period of time. But even in children, air pollution can affect the mind. In 2008, the American Journal of Epidemiology published a study showing that children exposed to high levels of black carbon performed worse on exams testing verbal and nonverbal IQ, as well as memory.
The reason for air pollution's negative effects upon mental state is not entirely understood, however some research points to the role of molecules within the brain. A professor of neuroscience at the Ohio State University conducted a 2011 study examining the brains of mice exposed to pollutants; eventually finding that those animals breathing in more air pollution had higher levels of cytokines in their brains. Cytokines are a molecule involved with the immune system and inflammatory responses, and it is interesting to note that the brains of Alzheimer's patients also have higher than normal amounts of cytokines.
With such compelling international research into the health dangers of smog, it's no wonder China is eager to shed its label as the most polluted nation on the planet. Through better vehicle regulation, such as that proposed this week in Shijiazhuang, and more vigilant monitoring of industry, there is certainly hope that China can clean up its act.