By A. Chris Gajilan
CNN Medical Senior Producer

It’s been one of the toughest and most complex stories I’ve ever worked on: Smokestacks belching dark clouds of lead, arsenic, cadmium into the air; children live with more than four times the safe limit of lead pumping through their blood; people who believe they have lost loved ones to the toxic conditions of where they live.

Dr. Sanjay Gupta interviews Leslie and Jack Warden in Herculaneum, MO

Dr. Sanjay Gupta and I have been traveling for the upcoming documentary “Planet in Peril: Battle Lines.” We visited the small town of La Oroya, Peru a couple of times during the past year. This town nestled in the Andes mountains is home to the Doe Run Peru smelting complex, where metal-laden rock is brought for processing into raw materials such as lead, copper and zinc. It is a place where the air irritates the eyes, befouls the mouth, stings the nostrils and heavies the chest. In this town of 35,000 people, 99 percent of children living in and around La Oroya have blood lead levels that exceed acceptable limits, according to studies carried out by the director general of environmental health in Peru in 1999.

Consider this: People shouldn’t naturally have lead in their bodies. The upper safe limit set by the World Health Organization is 10 mg/dL. But even more recent findings from La Oroya show that the situation is still very grim. We were joined there by Fernando Serrano, a St. Louis University researcher, whose 2005 study found that children had an average blood lead level of 36.1 mg/dL to 32.4 mg/dL. That’s more than three times the safe limit!

Lead poisoning is insidious. Children who have high levels of lead in their bodies can appear healthy but may suffer long-term consequences such as developmental disorders, mood disorders and in some cases, retardation. The young are most at risk because their tissue is more susceptible to the toxicities of lead.

Doe Run Peru took over the smelter in La Oroya in 1997, after it had already been operating for decades under other companies. We interviewed Doe Run Peru's president, Juan Carlos Huayhua. While his company is making major technological improvements and sponsoring community health programs, it recognizes that more needs to be done. In cooperation with the Peruvian government, Doe Run Peru runs a small nursery school for about 100 children whose blood lead levels exceeded 40 mg/dL. There are thousands of kids who live within a two-mile radius of the smelter.

Yesterday, we visited a sister company, Doe Run Missouri in Herculaneum, where lead is also processed. In that small town, the company agreed to a plan to help clean up the area, including a buyout of about 160 homes, in the area about 3/8 mile from the smelter.

In both towns the battle lines are drawn. We have found that the environmental conditions have improved in recent years. While the company and some residents and workers say they are doing all they can, others say it's far from enough.

Do you have loved ones who work in difficult environmental conditions? Have you ever had to make a choice between health and livelihood?

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