GREEN LIGHTING: A girl stands in front of a billboard listing the differences in power consumption between a compact fluorescent lamp and an incandescent lamp during a tour exhibition on carbon emission reduction in Guiyang, southwest China's Guizhou Province (QI JIAN)

Zhang Hong is a program director at the Global Village of Beijing, an established environmental NGO. Zhang's organization has carried out a program of promoting the replacement of incandescent lamps with energy-efficient compact fluorescent lamps (CFLs) since 2006. When Zhang realized that the mercury residue in the "greener" fixtures might make a mess of the environment, he began to include the safe disposal of spent lamps into his lectures.

However, as there is no CFL-disposal service available in residential communities in Beijing, Zhang suggested storage of burned out lamps to his audience since intact CFLs will hold their mercury indefinitely. He himself once stored more than 20 fluorescent lamps in a corner of his office before sending them to a hazardous waste recycling center.

Zhang has also persuaded company sponsors of his organization's CFL promotion campaign into donating money to educating the public on reducing mercury pollution.

Under a three-year program launched by the Chinese Government in 2008, individual purchasers of CFLs manufactured by companies winning government bids enjoyed a 50-percent discount and organizational purchasers enjoyed 30-percent subsidies. The program set a goal of promoting the use of 150 million energy-saving lighting products nationwide, which could reduce pollution by 29 million tons of carbon dioxide and 290,000 tons of sulfur dioxide every year. By the end of 2011, the program had subsidized the purchase of 500 million CFLs nationwide.

Despite the program's enormous success in energy conservation, people are now concerned that the mercury in the expired lamps is not kept out of landfills and incinerators. Jiefang Daily, a Shanghai-based newspaper, reported on December 6, 2012, that more than 100 million CFLs in China were reaching the end of their lifespans.

Unlike LED and incandescent lamps, CFLs contain mercury. No mercury is released when the bulbs are intact or in use, but if the bulb breaks, as much as 5 mg of mercury may be released.

Although 5 mg—around the size of the tip of a ballpoint pen—is a tiny amount when compared to the 1 to 3 grams in a mercury thermometer, the vast number of spent lamps can accumulate into a major source of severe pollution.

Scientists have confirmed that the mercury in a CFL can pollute more than 100 tons of water and the surrounding soil after it reaches a landfill, where bacteria convert it to far more toxic organic mercury compounds such as methyl mercury, which can be absorbed through skin or mucous membranes.

Improper disposal of CFLs in landfills or incinerators may also release mercury vapor into the atmosphere.

According to the China Association of Lighting Industry, China produced around 4.7 billion CFLs in total in 2011 and 1.8 billion of them stayed in China. If every lamp contains 5 mg of mercury on average, without proper disposals, lamps consumed in China would release a total of 95 tons of mercury, which could stay in the atmosphere for up to one year and travel around the globe.

An ignored issue

The first step of processing CFLs involves crushing the bulbs in a machine that uses negative pressure ventilation and a mercury-absorbing filter or cold trap to contain mercury vapor. The crushed glass and metal are stored in drums, ready for shipping to recycling factories.

Many municipalities and provinces on the Chinese mainland have purchased such machines. But underutilization is common among CFL recycling facilities nationwide, reported China Youth Daily.

Even in Beijing, which has the earliest recycling program for CFLs among Chinese cities, still only a small proportion of burned out lamps are disposed of as hazardous waste. The Beijing Hazardous Waste Disposal Center has the city's only machine to dispose of waste CFLs, which was put into operation in 2008. An anonymous technician from the company told Beijing Review that although the Sweden-made machine could recycle up to 1,500 CFLs per hour and the government subsidizes the center 1 yuan ($0.16) per lamp, it is left idle many days a year, as only a small number of organizations and virtually no individuals bring spent lamps.

Unlike in many other countries, the presence of mercury in fluorescent lights is neither well known nor well communicated to the Chinese public. Special handling instructions for breakage are not printed on the packaging of household CFL bulbs.