Compelling photographs show dust-strewn children in recycling plants and making coloured balloons in Dhaka.
Minimum working age in Bangladesh is 14, but 93% of child labourers work in small workshops and slip under radar.
Last week the city marked the first anniversary of the Rana Plaza garment factory collapse which killed 1,135.
Disaster prompted a surge in factory unions and inspections, but many still work in dangerous conditions.
The balloon factory is not the most hazardous line of work. Some children work in farming, spreading dangerous chemicals without adequate protection.
Old and young workers exist side-by-side, often in improvised conditions. The minimum wage is around $66 a month, but children earn less.