"Beijing produces 17,400 tons of garbage every day, but the local garbage processing plants can process only 10,400 tons of them. Unless the gap is covered, the metropolis would be surrounded by garbage four years later." A media outlet made this prediction in 2014.

It has not come true, however.

Why? Because local garbage collectors, more than 100,000 of them, covered the gap－with their hands, literally. According to official data, garbage collectors can process 4 million tons of the 7 million tons of garbage Beijing produces every year, and thus can help recycle tens of thousands of tons of reusable materials.

Without them, the unprocessed garbage would have covered 11,900 square meters of land, and produced more than 70,000 cubic meters of dirty, even toxic, liquid which could have percolated to the underground water table. The resultant water and soil contamination would be beyond estimation.

Beijing's garbage collectors work the traditional but laborious way. They carry a bag, use their bare hands to search through the garbage to look for everything that is reusable. They collect empty plastic bottles, used paper, even nails, put them in separate bags, and then sell them to companies that recycle and turn them into new materials.

Once the garbage collectors are through with their painstaking work, the remaining garbage could be safely burned, because they meticulously remove everything such as plastic and metals that is harmful and causes high pollution when burned.

Garbage collectors not only prevent pollution, but also save large quantities of resources. According to China Nonferrous Metal Industry Association's estimates, recycling of metals saved 110 million tons of coal and 9 billion tons of mineral resources for China between 2001 and 2011, and garbage collectors made a major contribution to this recycling process.

Yet the working environment for garbage collectors is extremely unhygienic. Since many people do not sort garbage at home, garbage collectors have to separate metals and plastics from fish bones, eggshells, even used toilet paper. The stench in the garbage dumps is hellish. In the summer, they are often swarmed by flies and have to pick the reusable materials from rotting materials full of maggots.

Hazards such as broken glass and other sharp objects are common, as they are all mixed up with the reusable materials. In 2016, a photo of a garbage collector's hands with at least two dozen cuts caused by broken glass went viral online.

That's the most ironic and painful part of a garbage collector's life: despite making major contributions to China's waste processing, they continue to suffer because many people refuse to develop the habit of sorting garbage at home.

The problem is that, if people refuse to sort garbage at home, Beijing's garbage collectors may give up the hazardous work. An official from the Beijing Municipal Commission of City Management said the number of garbage collectors in Beijing dropped from 150,000 in 2009 to 100,000 in 2014, and it might drop further if people don't change their habits.

As social welfare improves, many young people might prefer to live on welfare allowances instead of working amid hazards, flies and maggots, and a deathly stench. Worse, unlike street cleaners, garbage collection is not considered a formal job, and most garbage collectors have no social security.

If garbage collectors stop working before Beijing manages to set up a modern garbage sorting system, the city might find itself surrounded by garbage one day. News reports say Shanghai is amending its regulation on garbage. The new draft, submitted to the local legislature, emphasizes the role of every resident in garbage sorting, starting from home. Let us hope Beijing, for once, will follow the example of Shanghai－for the sake of the environment and to make the work of garbage collectors less dangerous and painful.

The author is a writer with China Daily.