United Nations agencies — the World Health Organization (WHO) and the World Meteorological Organization (WMO), with contributions from the International Labour Organization (ILO) — have warned that climate change is driving dangerous levels of workplace heat stress globally.
In a joint technical report released on Friday, 22 August 2025, the agencies identified West and Central Africa — where Nigeria is located — as among the regions most severely affected by heat exposure at work. They cautioned that the situation will worsen unless urgent adaptation and mitigation measures are introduced.
The report, titled Climate Change and Workplace Heat Stress: Technical Report and Guidance, revealed that outdoor workers in agriculture, construction, and mining are the most vulnerable. Informal workers across West Africa, many of whom lack social and legal protections, are also heavily exposed.
The report linked rising global temperatures to dehydration, heat exhaustion, kidney damage, cardiovascular strain, and reduced work capacity. It warned that countries in West and Central Africa face disproportionate risks because of the high number of workers in outdoor and informal labour.
According to the UN, more than 2.4 billion workers — representing about 71 per cent of the global workforce — are currently exposed to excessive heat, resulting in an estimated 22.85 million occupational injuries and nearly 19,000 deaths every year.
In West Africa, where agriculture and informal outdoor labour dominate, economic losses from reduced productivity due to heat stress are already substantial and expected to grow. The report stressed that informal workers remain particularly vulnerable because they lack adequate protections.
It further highlighted the economic consequences, stating: “For every one degree Celsius rise above a wet-bulb globe temperature of 20°C, labour productivity declines by 2 to 3 per cent.”
The agencies called for urgent risk-reduction measures, including the adoption of national occupational heat action plans, early warning systems, and workplace interventions such as mandated rest breaks, hydration support, and heat-adapted clothing and facilities.
Concluding, the report stated: “Heat stress has become one of the most severe occupational hazards of our time,” urging governments to act decisively to safeguard workers’ health and livelihoods in a warming world.
