Peru's industrial progress is proving costlier than expected as protests widen over industrial pollution, contamination of underground water resources and lead poisoning.

Peru depends on exports of minerals and other raw materials, including gold, and has drawn many international investors to its untapped natural resources, with support from President Ollanta Humala's administration.

More investors want to work with Peru but are deterred by protests by rural groups and environmentalist campaigners, published economic data indicated.

More than 19 people have died in disputes over natural resources since Humala assumed office in July 2011. Peruvian and international advocacy groups cited more than 200 cases of potentially lethal pollution caused by mining and other industrial activities.

A World Health Organization-backed study compared lead contamination levels in the soil in and around two mining areas in Peru, one of the world's top producers of silver, copper, gold, zinc and lead.

Dangerously high levels of lead were found in the soil of Cerro de Pasco, a historic Andean mining town, where copper mining continues. The pollution levels were lower in Huaral, which has a modern mine and ore processing plant.

Talks called by the Organization of American States in Lima this week looked into measures to ease popular unrest over adverse social and environmental impact of controversial mining activities.

Peru's frequent spats with advocacy groups who oppose largely unregulated mining figured at a two-day meeting of experts invited by the OAS to "discuss management of socio-environmental conflict for the countries of Central America and the Andean Region."

Peruvian unrest over the effect of mining and deforestation on the environment dates back three administrations. Both former Presidents Alejandro Toledo and Alan Garcia had to deal with frequent protests, leading to deaths and injuries on both sides.

Armed government forces often found themselves confronting indigenous campaigners armed with spears and arrows.

Supporters of the government development plans say Humala and previous administrations have all faced a "dilemma": Does the government go ahead with plans to develop mining and forestry to help ease poverty or does it yield to indigenous protesters that have been living for years in those areas and their backers?

Critics say much of the conflict has been driven by inept handling of the protesters by politicians from successive regimes.

An OAS statement said the talks aim to provide "a space for reflection, analysis and debate on the dynamics of socio-environmental conflict."

It hopes "mechanisms can be found for the appropriate management of these conflicts using the national experiences of participating countries and input from experts in the field."

Ministers and senior officials involved with the ongoing conflict are taking part in the talks.

OAS says it aims to encourage citizen participation in public policy formation, prior consultation, early warning systems and dialogue as tools for conflict management.