Depending on where in the United States you live, you may have experienced your fair share of smog. You’ve learned to keep your car windows rolled up on certain days. You know the unmistakable smell of thick, black pollution. In China, smog is such a toxic problem that the country expects to have more than 800,000 cases of lung cancer a year by 2020.
On Monday, air pollution in some parts of Beijing reached the maximum on the government’s official index, topping out at 500. By late afternoon, 17 of 33 official monitoring stations showed the frightening readings, which the government calls “severely polluted.” It’s so bad that it’s 20 times what the World Health Organization (WHO) considers to be safe. 
In the U.S., readings of above 300 are considered extremely rare and typically only occur during forest fires and other major events. The Environmental Protection Agency (EPA) considers an index over 100 to be unhealthy. The agency says a reading over 300 “would trigger a health warning of emergency conditions.” 
According to state-run China Daily, medical experts are predicting the horrible pollution will result in 800,000 new diagnoses of lung cancer each year and 700,000 annual deaths from the disease by 2020. The country already had more lung cancer diagnoses and deaths than any other nation, with about 600,000 people succumbing to the disease per year. Some 700,000 people have been diagnosed with lung cancer this year.
If pollution-related lung cancer doesn’t kill people in China, smoking cigarettes just might. China is the largest consumer of tobacco products in the world, and a study earlier this year estimated that 1 in 3 young Chinese men will die of tobacco-related illnesses. Some experts say pollution will eventually replace smoking as the leading cause of lung cancer in that nation.
“The rapid increase of the disease will last for at least 20 years,” Zhi Xiuyi, who heads the Lung Cancer Diagnosis and Treatment Center at Capital Medical University in Beijing, told China Daily.
Right now, the smog is so thick in China that most sunlight has been blotted out. Millions of people have been instructed to stay indoors, and most factories and schools are closed. Authorities are reportedly blaming “unfavorable weather” and coal fires on the smog spike, but coal-fired power plants on overdrive from a temperature dip last week have combined with stagnant high pressure, creating a pollution nightmare.
Current pollution levels in China can result in premature death, aggravated asthma, irregular heartbeats and decreased lung function. Air pollution has even been linked to suicide.
The elderly are especially susceptible, but current smog levels are off the charts even for the healthiest Chinese citizens.