In many low- and middle-income countries (LMICs), informal industries pose a formidable challenge to environmental regulation and pollution control. These sectors, often operating beyond the scope of formal governance and oversight, contribute substantially to local and global emissions yet remain largely unmonitored and poorly managed. Among such sectors, Bangladesh’s brick manufacturing industry stands out for both its scale and its impact on air quality. Predominantly relying on traditional, coal-fired “zigzag” kilns, this industry has long been a significant source of carbon dioxide and fine particulate pollution, exacerbating health problems and environmental degradation in the region. Despite the urgency, efforts to introduce new, advanced technologies into these informal setups have met with limited success, hindered by enforcement gaps, corruption, and misaligned economic incentives.
A recent groundbreaking study by Nina Brooks and colleagues offers a transformative perspective on tackling pollution from these informal brick kilns. Rather than advocating for costly technological overhauls or relying on often ineffective regulatory measures, the researchers devised an intervention focused on operational efficiency. Their approach centers on simple, cost-free modifications in kiln management — specifically optimizing how fuel is fed and bricks are stacked within these zinc-zag kilns — that can dramatically reduce emissions without requiring capital investment. This pragmatic strategy aligns environmental benefits with economic incentives, opening the door for rapid adoption among producers constrained by financial and institutional barriers.
The research, published in Science, reported findings from a randomized controlled trial engaging 276 zigzag kiln operators in Bangladesh. About 65% of participants who underwent training and received technical support adopted the recommended energy-saving practices. This uptake is notable given the historical resistance to new technologies in this sector. The operational changes introduced were elegantly straightforward, tapping into existing knowledge while emphasizing efficiency in fuel consumption and combustion processes. Such measures produced a commendable 10 to 11% reduction in energy use, coupled with an 8.8% cut in carbon dioxide and fine particulate emissions — improvements that bear significance for both local air quality and climate mitigation.
Importantly, the intervention extended benefits beyond emissions reductions. Producers reported decreases in fuel expenses alongside improvements in brick quality, underscoring the multifaceted advantages of the approach. The visible, immediate economic returns appear to have been pivotal in encouraging durable adoption of these practices. Intriguingly, the study found that the cost-benefit ratio of the intervention favored the producers by an astonishing factor of 65 to 1, revealing that environmental and financial objectives need not be at odds, even in marginalized industrial segments. This realignment of incentives stands in stark contrast to previous attempts focusing on deploying expensive technologies that saw limited uptake despite heavy subsidies and policy promotion.
At the heart of this research lies an acute understanding of the informal industry’s socio-economic context. Brick kiln operators, often small-scale entrepreneurs, operate within tight financial margins and face systemic vulnerabilities including weak regulatory oversight and vulnerability to coercion or corruption. These factors contribute to the industry’s resistance to expensive capital investments or changes that promise only uncertain gains. By emphasizing modest operational improvements that avoid upfront costs, the researchers successfully navigated these contextual hurdles. The scalable nature of these interventions suggests a compelling blueprint for other informal industrial sectors globally where top-down regulation remains elusive.
Technically, the "zigzag" kiln design itself provides a conducive platform for such operational modifications. Unlike traditional kilns with linear airflow, zigzag kilns enhance combustion efficiency by channeling flue gases through a labyrinthine path, improving heat transfer and fuel burning. However, suboptimal fuel feeding rates and inconsistent brick stacking compromise these benefits, leading to higher emissions and fuel wastage. By providing targeted training on feeding coal at appropriate rates and arranging bricks to maximize air circulation and combustion completeness, the intervention unlocked latent energy efficiency potential inherent in existing infrastructure. This nuanced understanding of kiln mechanics was central to the intervention’s success.
The implications extend beyond Bangladesh, providing an empirical model for policy frameworks in LMICs grappling with pollution from informal industries. Traditional regulatory approaches often falter due to limited enforcement capacity, corruption, and the informal status of enterprises. The study underscores an alternative: market-friendly, behaviorally informed interventions emphasizing knowledge transfer and operational refinements. Such mechanisms can be particularly effective in contexts where formal mandates are impractical. The intervention’s success story calls for international development agencies and local governments to rethink pollution control strategies with greater emphasis on field-validated, low-cost solutions that empower producers.
Additionally, the study weighs in on the broader discourse concerning technology adoption in marginalized sectors. Prior initiatives promoted advanced brick kiln technologies promising greater energy savings and emission reductions. Yet, these often fell short when confronted with ground realities such as lack of capital, maintenance challenges, and mismatches between experimental and real-world conditions. The failure of high-tech solutions highlights the critical need for solutions tailored to users’ socio-economic constraints and practical knowledge. Brooks et al.’s study advances the argument for "appropriate technology" — simple, accessible, and cost-neutral practices integrated within existing economic ecosystems.
Health impacts are another vital dimension of the study’s significance. Fine particulate matter (PM2.5) and carbon dioxide emissions from brick kilns contribute substantially to ambient air pollution. In Bangladesh, air pollution exacerbates respiratory ailments, cardiovascular diseases, and premature deaths, placing a heavy burden on public health infrastructure. By cutting emissions through operational efficiencies, the intervention offers a dual dividend: improving public health outcomes while safeguarding livelihoods. This harmonious approach embodies sustainable development principle, balancing environmental protection with economic empowerment.
From an energy perspective, reducing coal consumption by 10–11% translates to considerable reductions in greenhouse gas emissions on a national scale, given the sheer number of informal kilns operating in the country. While individually modest, such marginal gains aggregated across hundreds or thousands of kilns can meaningfully shift national emissions trajectories. In the era of heightened global focus on climate action, this micro-level intervention exemplifies the power of decentralized solutions – particularly vital for LMICs where large-scale technological overhauls remain challenging.
The study also underlines the importance of behavioral change facilitated through technical training and support. Knowledge transfer, coupled with practical demonstrations, is shown to be effective in bridging the gap between scientific insights and artisanal production methods. This human dimension – supporting kiln operators as agents of change – emerges as a cornerstone of intervention success. It suggests that future pollution reduction programs should consider holistic approaches that incorporate social, cultural, and economic factors alongside technical guidance.
Scaling up this intervention could have transformative implications both for Bangladesh and for the wider developing world. It presents a robust alternative to the traditional model of environmental governance focused on regulation and enforcement, particularly in contexts marked by informality and governance deficits. By harnessing simple operational improvements that benefit producers directly, the approach may catalyze widespread adoption that regulatory bodies alone could never achieve. The low-cost, replicable nature of the intervention significantly enhances its appeal as a development and climate strategy.
Ultimately, Nina Brooks and colleagues offer a refreshingly pragmatic blueprint for simultaneously addressing environmental degradation and economic well-being in informal industries. Their work disrupts canonical views on technology adoption and environmental control, emphasizing that solving complex problems sometimes involves returning to fundamental practices with a focus on efficiency and feasibility. This research marks a pivotal contribution to the literature on sustainable industrial development, environmental economics, and public health in the context of LMICs, and holds promise for reshaping policy and practice in the coming decades.
Subject of Research: Environmental and economic performance improvement of informal brick kilns through operational efficiency interventions
Article Title: Reducing emissions and air pollution from informal brick kilns: Evidence from Bangladesh
News Publication Date: 8-May-2025
Web References: http://dx.doi.org/10.1126/science.adr7394
Keywords: informal industry, brick kilns, Bangladesh, emissions reduction, air pollution, zigzag kiln, energy efficiency, low- and middle-income countries, operational intervention, coal consumption, carbon dioxide, particulate matter, sustainable development
