ROTTERDAM, the Netherlands  When two inspectors swung open the doors of a battered red shipping container here, they confronted a graveyard of Europe’s electronic waste  old wires, electricity meters, circuit boards  mixed with remnants of cardboard and plastic.

“This is supposed to be going to China, but it isn’t going anywhere,” said Arno Vink, an inspector from the Dutch environment ministry who impounded the container because of Europe’s strict new laws that place restrictions on all types of waste exports, from dirty pipes to broken computers to household trash.

Exporting waste illegally to poor countries has become a vast and growing international business, as companies try to minimize the costs of new environmental laws, like those here, that tax waste or require that it be recycled or otherwise disposed of in an environmentally responsible way.

Rotterdam, the busiest port in Europe, has unwittingly become Europe’s main external garbage chute, a gateway for trash bound for places like China, Indonesia, India and Africa. There, electronic waste and construction debris containing toxic chemicals are often dismantled by children at great cost to their health. Other garbage that is supposed to be recycled according to European law may be simply burned or left to rot, polluting air and water and releasing the heat-trapping gases linked to global warming.