Wood-fuelled bakeries third-largest cause of city’s pollution: study

MUMBAI: Bakeries are the third-largest source of air pollutants in Mumbai, a cause chiefly attributed to the prevalence of scrap wood as the fuel source in them, found the Bombay Action Environmental Group (BEAG) during a survey of bakeries.
Of the 628 bakeries in the city, the group set out to survey a random sample size of 200 in August 2023. What they found was that 47.1% were fuelled by scrap wood, which not only contributes to the pollutants PM2.5 and PM10 but also the far more dangerous and carcinogenic volatile organic compounds (VOCs).
“Those running the bakeries were under the false impression that wood is the cheapest source of fuel, when it is actually electricity that is the most cost-effective,” explained Dr Tuhin Banerji, project head for the study. “While electricity costs ₹3 to convert a kilogramme of flour into pav (bread), PNG costs ₹8.81 and scrap wood ₹15.”
What makes the use of scrap wood particularly dangerous is that it comes along with the residue of its old life such as wooden frames of doors, windows and furniture, glue, resin, paint, rusted nails and other metallic parts. Between 50 and 100 kg of this scrap wood is burned on an average by bakeries. Burning these leads to the emission of carcinogenic VOCs, affecting those operating the ovens and neighbouring residents.
Several bakeries were, however, adamant about sticking to scrap wood fuel. “Some bakery workers and owners believe that wood imparts a better flavour to bakery products while others just didn’t want to change their age-old practice of using wood,” said Banerji.
A lack of information too plays a large role in keeping the bakeries steeped in their old ways. “Many old bakeries are nestled in old residential areas,” said Banerji. “Their owners have leased them out, and they are managed, run and worked by poor migrant workers from Uttar Pradesh and Bihar. They are poor, and feed the poor with the staple food, pav. For them to make that leap to a cleaner fuel, they will need information and some guidance.”
Cleaner fuels come with their hiccups for the bakeries. PNG, for instance, can even be accommodated in the same ovens, but PNG lines don’t run in slums. Electricity, the cleaner and cheaper alternative, would require the ovens to be changed, which the bakeries don’t want. “However, this cost in infrastructure change can easily be offset by the cost-effectiveness of the fuel,” points out Banerji.
The positive perspective that emerged from the study was that the 49% bakeries that run on electricity, some with LPG as a back-up, had all converted from wood-based bakeries. “They realised that using electricity was cheaper, so they chose to make the change themselves,” said Banerji. “City Bakery at Worli has even added a shop front where the bakery workers sleep in the space that emptied out on account of not having to store wood.”
To increase this conversion rate, a little help is needed from the BMC or the Maharashtra Pollution Control Board, said Banerji. “This should be in the form of information and training, letting the bakeries know that electricity is economical and better for their health,” he said. “Some incentive or cost-sharing would also be beneficial, especially for the poorer bakers.”