Across
- 1. trapped heat warms the planet
- 4. acid rain or toxic particles settling
- 5. formed by primary pollutants
- 8. CO2, methane, etc.
- 9. Rampant arboreal destruction
- 13. naturally decomposes
- 15. harmful gases
- 17. loud sounds damage hearing
- 18. synthetic materials
- 19. harmful substances released directly
- 20. toxic chemicals found in the ground
Down
- 2. earthquakes, typhoons, volcanic eruptions
- 3. lead,mercury,arsenic etc.
- 6. forms smog
- 7. nuclear contamination spreads
- 10. factory smoke and chemical waste
- 11. short term energy source
- 12. organic matter
- 14. can resist microbial decomposition
- 16. naturally replenished energy source