Question

Read the passage below carefully:

For decades, the informal processing of electronic waste across West African urban hubs provided basic livelihoods at devastating environmental and public health costs. Unregulated open-air burning of circuit boards released toxic heavy metals into soil and water systems, poisoning surrounding communities. Recently, however, a shift toward formalized circular economy frameworks is transforming this dangerous industry into a sustainable economic driver. Modernized recovery facilities now utilize specialized mechanical shredding and hydrometallurgical extraction to safely salvage high-value precious metals like copper, gold, and palladium. By integrating informal waste pickers into cooperative collection networks, municipal authorities guarantee a consistent supply of raw materials to these processing plants while enforcing safety protocols. Initial health assessments around reformed recycling hubs show marked reductions in atmospheric lead contamination and occupational respiratory ailments. Crucially, local electronics manufacturers have begun purchasing these refined secondary raw materials, reducing national reliance on expensive mineral imports. While capital expenditure for advanced recycling technology remains a barrier for smaller municipalities, the economic and environmental dividends of formalizing e-waste management demonstrate its necessity for sustainable urban development.

Match each statement from the passage (Statements 1–4) with its correct structural role in distinguishing core summary ideas from supporting details.