Cleaner brick kilns cut pollution, but gains did not reach workers, research finds

Researchers tested whether traditional kilns could become cleaner without costly replacement technology. They focused on changing daily operations rather than rebuilding kilns. This mattered because Bangladesh has thousands of older kilns, and moving or regulating them alone cannot remove pollution from a densely populated country.

The team trained owners, managers and workers to feed coal into kilns more continuously. They also changed how bricks were stacked, allowing air to circulate more efficiently. Other steps reduced heat loss. None required owners to buy major equipment or replace their kilns.

The approach produced measurable gains across hundreds of kilns. Energy use fell about 10.5% in intervention kilns, and owners used less fuel while producing more higher-quality bricks. Kilns that adopted the practices because of the intervention saw energy use fall about 23%. Adoption continued and increased the following firing season, because the changes saved money.

Bangladesh’s brick industry is central to the country’s rapid urban growth. The country ranks as the world’s fourth-largest brick producer. Its traditional kilns are especially important because they provide most of the bricks used domestically, rather than serving only a small or specialized market.

Approximately 8,000 traditional kilns operate across Bangladesh. Together, they supply more than 90% of the country’s domestic brick consumption. This scale means that even modest improvements at individual kilns could affect national fuel use and pollution.

The industry’s size also makes change difficult. Brickmaking produces substantial carbon emissions and PM2.5, a fine particle pollutant. Bangladesh is densely populated, so simply moving kilns away from schools, health facilities and cities is not feasible, according to Nina Brooks. Researchers therefore examined whether existing kilns could operate more efficiently.

The intervention made kiln production cleaner and more productive at the same time. Across kilns assigned to receive training and technical support, energy use fell about 10.5%. Carbon dioxide emissions declined by an estimated 171 metric tons per kiln over a firing season, and PM2.5 emissions fell about 0.45 metric tons.

The strongest results appeared among kilns that adopted the practices because of the intervention. Their energy use declined about 23%, while carbon dioxide and PM2.5 emissions fell by roughly 20%. The changes also lowered fuel costs, since owners needed less coal to produce bricks.

Product quality improved as well. Owners produced a greater share of higher-quality bricks, which added economic value while reducing pollution. The next firing season, adoption had not faded; it had increased. The results show that cleaner production can be attractive when it also saves money and improves output.

The cleaner methods continued because they made economic sense for kiln owners. The intervention did not depend only on environmental concern, outside enforcement or expensive equipment. It helped owners reduce fuel spending and produce more valuable, higher-quality bricks.

For example, researchers found that energy use declined across intervention kilns, while owners spent less on fuel. Among kilns that adopted the practices because of the intervention, energy use fell about 23%. The same operational changes also reduced carbon dioxide and PM2.5 emissions by roughly 20% in that group.

When researchers returned during the following firing season, adoption had not dissipated. Instead, it had increased. The findings suggest that financially beneficial practices can last even where environmental regulations are difficult to enforce. However, continued owner adoption did not automatically mean workers received better conditions or shared in the gains.

Brick-kiln workers operated in a large, mostly informal labor system with serious risks. The companion study examined working conditions because researchers wanted to know whether more productive kilns would also improve workers’ lives. Instead, it found widespread evidence of poor and coercive conditions.

Among the 1,442 workers interviewed, 70% reported lacking personal protective equipment. Another 71% said they did not have a formal labor contract. At 42% of the kilns studied, workers reported limited freedom of movement or communication, suggesting that some workers had little control over where they went or whom they contacted.

These findings matter because productivity gains can stay with business owners. The cleaner-kiln intervention lowered fuel costs and improved brick quality, but the article reports that workers did not benefit in the short term. Cleaner production therefore addressed pollution without resolving the labor problems embedded in the industry.

Labor trafficking generally means recruiting or keeping people in work through force, threats, coercion, deception or abuse of vulnerability. In brick kilns, debt or advance payments can become tools of control when workers cannot freely leave. The article describes these arrangements but does not legally classify them as trafficking.

Child labor means work performed by children below the legal age or in harmful conditions. The article does not provide figures or findings about children working in Bangladesh’s kilns, so no conclusion about child labor can be drawn from this source. Informal employment means work outside formal contracts or standard legal protections.

The study found that 71% of workers lacked formal labor contracts. It also reported debt, advance payments, long hours, limited worker mobility and hazardous conditions. These facts describe vulnerability and informality, but they do not by themselves establish trafficking or child labor in every kiln.

Higher productivity increases the value a business gets from each unit of fuel, time or labor. But workers receive a share only if wages, contracts or bargaining power connect their pay to those gains. Owners may instead keep savings as profit, especially when employment is informal and protections are weak.

The kiln intervention shows this mechanism clearly. Owners used less fuel and produced more higher-quality bricks, which improved their finances. Yet the companion study found that 71% of workers lacked formal contracts, 70% lacked protective equipment and 42% reported limited movement or communication. Those conditions gave workers little clear route to claim a share.

The research found that gains did not improve worker conditions in the short term. This does not mean productivity cannot help workers later. It means cleaner technology alone is insufficient. Better labor protections, contracts and mechanisms for sharing gains would be needed to connect business improvements with worker welfare.