What WHO estimates each would save, cost and return in a year
Water, sanitation and handwashing count only the tenth of benefits and costs WHO attributes to climate-proofing. Return is benefits minus costs per $1, as WHO reports it.
Source: WHO, Global benefits and costs of prioritized actions on climate change and health (2026); 2024 US$
| Measure | Lives saved a year | Cost a year | Return per $1 |
|---|---|---|---|
| Heat-health warnings | 100,000 | $0.23bn | $835 |
| Clean cooking | 90,000 | $5.15bn | $51 |
| Handwashing | 80,000 | $5.82bn | $32 |
| Drinking water | 60,000 | $17.79bn | $6 |
| Sanitation | 30,000 | $6.43bn | $13 |