Two 13-year-old boys and a 15-year-old boy pour crushed gold ore over a sisal sack to concentrate the particles of gold at a processing site in Mbeya Reigon, Tanzania. (Justin Purefoy, Human Rights Watch)
While boys "dig and drill in deep, unstable pits" in informal mines, working underground for shifts as long as 24 hours, girls around the small-scale mines face sexual harassment and pressure to become prostitutes, the US-based rights group warned in a report released on Wednesday.
Tanzania is Africa's fourth largest gold producer, and the precious metal is the top foreign exchange earner for the country, with exports topping $1.8-billion in the first six months of 2013, according to the central bank.
Small-scale mines extracted 1.6 tonnes of gold in 2012 worth some $85-million, with the bulk exported to the United Arab Emirates, as well as to Britain, China, South Africa and Switzerland.
"Thousands of children work in licenced and unlicenced small-scale gold mines in Tanzania," HRW's report read, based on visits to 11 sites across the East African nation.
Many of the children are at risk of being poisoned by the dangerous mercury used to extract gold from raw ore, Human Rights Watch (HRW) said.
"The employment of children in dangerous mining work is one of the worst forms of child labour under international agreements, to which Tanzania is a party," it added.
Calls to curb the practice
HRW called on the government, donor nations and producers to curb the practice, arguing that while Tanzania has strong anti-child labour laws the authorities have "done far too little to enforce them".
As Tanzania's mining industry grows, HRW stressed the importance of ensuring that production respects basic human rights.
It noted that a $5-million World Bank project supporting the mining sector does not directly address the problem of child labour.
The United Nations Environment Programme last year estimated that between 50 000 and 1.5-million Tanzanians are employed in the informal gold mining sector.
"Tanzanian boys and girls are lured to the gold mines in the hopes of a better life, but find themselves stuck in a dead-end cycle of danger and despair," said HRW children's expect Janine Morna.
"Labour inspectors need to visit both licenced and unlicenced mines regularly, and ensure employers face sanctions for using child labour."