Rounding up polychlorinated biphenyls (PCBs), the once-prized synthetic compounds that have become one of the world’s most ubiquitous industrial pollutants, is no small challenge for Latin American governments. PCBs, after all, were used intensively for 40 years in everything from electrical transformers to lubricating oils before their danger as a persistent organic pollutant became clear.

But another challenge is to dispose of PCBs once they’ve been collected. This issue underlies criticism now being leveled at Mexico’s Federal Electricity Commission (CFE), the state-owned company that maintains a near monopoly on the nation’s power generation.

Last month the CFE shipped 300 tons of PCBs from the eastern port of Veracruz to Spain and France for incineration as part of its effort to meet a Dec. 31, 2008 government deadline for eliminating PCBs in the power industry. The move drew criticism from Greenpeace Mexico, which warns PCBs might be spilled at sea and points out that the compounds release harmful dioxins and furans when incinerated.