Marcos Orellana, a UN special rapporteur on hazardous substances, directly accused the United States of using Mexico as a dumping ground for industrial pollution and waste. His findings detail how lax environmental enforcement and inadequate oversight in Mexico have allowed toxic accumulation to persist unchecked.

Orellana's investigation revealed that US companies exploit Mexico's weaker environmental standards to operate factories that produce goods for American consumption while generating hazardous pollution. Mexican communities near industrial zones face direct exposure to toxic air, water contamination, and accumulated waste. The Guardian and investigative outlet Quinto Elemento Lab corroborated Orellana's findings through separate reporting on industrial boomtowns like Monterrey, where residents described "breathing poison."

The pattern reflects a broader structural problem. Trade relationships under agreements like NAFTA and its successor USMCA have incentivized manufacturing relocation to Mexico, where environmental compliance costs remain substantially lower than in the United States. Companies operate within Mexican law, but Mexican law itself remains permissive on emissions, waste disposal, and industrial monitoring compared to US Environmental Protection Agency standards.

Orellana documented hazardous substances ranging from imported waste to chemical pollutants crossing the border with minimal regulation. Affected Mexican communities lack resources to challenge industrial operations or remediate contaminated sites. Border regions experience the compounded effects of pollution from both sides, with atmospheric and water systems carrying contaminants across jurisdictional lines.

The UN expert's characterization of Mexico as a "garbage sink" reflects the asymmetrical environmental burden created by economic integration. US manufacturers avoid domestic cleanup costs and stricter liability standards by outsourcing production. Mexican workers and residents absorb the health consequences. Birth defects, respiratory diseases, and cancer rates correlate with proximity to unregulated industrial zones.

Orellana's findings call for enforcement of environmental provisions within trade