When it comes to acid rain or oil spills or depleted fisheries or tainted groundwater or fluorocarbon propellants or radiation leaks or sexually transmitted diseases, national frontiers are simple irrelevant. Toxins don’t stop for customs inspections and microbes don’t carry passports. North America became a water and free-trade zone long before NAFTA loosened up the market in goods. Help us to share this great article. Your friends will appreciate it! 0share Facebook0 Twitter0 Pinterest0 LinkedIn0 Flipboard Tumblr0 Mix