No more pollo con mole for me. First comes the news that 40,000 pounds of Dagoba organic chocolate had to be recalled after a laboratory in Oregon, where the company is based, confirmed that three kinds of Dagoba chocolate bars contained high levels of lead.

Then Marion Burros reported in yesterday's New York Times that much of the chicken being sold in this country contains arsenic, and, even more disturbing, that arsenic is a government-approved additive in poultry feed, where it's used to kill parasites and promote growth.

Frederick Schilling, president of Dagoba Organic Chocolate, has flown to Ecuador, the source of the tainted cocoa, to find out what went wrong. Dagoba promptly recalled the products in question: the Eclipse and Los Rios chocolate bars, and Prima Materia 2-pound cocoa bricks, used for cooking.

"This is an isolated situation and we take this matter extremely seriously and have taken immediate measures to remove all of these products from the marketplace as quickly as possible," Jeff Williams, chief operating officer of Dagoba, told the Mail Tribune of Medford, Oregon.

How did the lead get into the cocoa in the first place? Chocolate has some of the highest levels of lead contamination of any food we eat, which is why chocolate manufacturers routinely test for it. Cocoa beans can become contaminated from lead in the soil, water, or air, but studies suggest that contamination more likely occurs during processing. Scientists have found it difficult to isolate the source of lead contamination in chocolate.

And how does arsenic get into the chickens we eat? Arsenic's a known carcinogen, and many experts believe that there's no safe level of consumption, because the effects of arsenic are cumulative. In addition to potentially causing cancer, arsenic may contribute to diabetes, heart disease, and a decline in mental functioning. Small children and, not surprisingly, people who eat a lot of chicken, are at greatest risk.

The chicken industry defends the practice of feeding arsenic to chickens, and thus, to us. "We are not aware of any study that shows implications of any possibility of harm to human health as the result of the use of these products at the levels directed," Richard Lobb, spokesman for the National Chicken Council, told the New York Times.

But the FDA set the tolerance level for arsenic in chicken decades ago, and hasn't revised it despite the fact that chicken consumption in the U.S. has tripled since 1960. The USDA even admitted in a 2004 study that "higher than previously recognized levels of arsenic in chicken combined with increasing levels of chicken consumption may indicate a need to review assumptions regarding overall ingested arsenic intake."

While the FDA dithers, some poultry producers, including Tyson, have voluntarily stopped using arsenic in their chicken feed. McDonald's says it doesn't use chicken with arsenic, either. Chicken from "boutique" poultry producers such as Bell & Evans and Eberley contains no arsenic, and any chicken sold as organic or antibiotic-free should be arsenic-free, as well.

A study from the Institute for Agriculture and Trade Policy measured the levels of arsenic in chicken sold in supermarkets and fast food outlets, and found that the amount of arsenic varied considerably, but none of the chicken had unacceptable levels of arsenic by the FDA's antiquated standards.

The study found that Perdue chicken contained arsenic, and the company acknowledged that they do sometimes use chicken feed containing arsenic. Some samples from the gourmet food chain Trader Joe's tested positive, too. Trader Joe's had no comment.

Guess I'll think twice about buying Trader Joe's chicken maple sausages. My mental functioning is already endangered enough from all that mercury-tainted tuna. Sausage, I can live without. But sushi? No way.