Suspect Salads: Lettuce May Be Toxic To Your Thyroid!

Toxic Rocket Fuel Found in Samples of Winter Lettuce

lettuce perchlorate thyroid

In the last decade, perchlorate contamination of water supplies has been considered a local or regional problem, and findings from the Environmental Working Group made perchlorate contamination a national issue of concern--resulting in regulatory action from the Environmental Protection Agency (EPA).

Research showed that lettuce grown in the fall and winter months in Southern California or Arizona may contain higher levels of toxic rocket fuel byproduct, perchlorate than is considered safe by the EPA  according to independent laboratory tests commissioned by Environmental Working Group (EWG).

The EWG says that simply by eating lettuce, 1.6 million American women of childbearing age were being exposed daily during the winter months to more perchlorate than the EPA's recommended safe dose.

According to media reports, the lettuce samples contained substantial quantities of perchlorate. One, which was a prepackaged variety of organic mixed baby greens, had a level of perchlorate contamination considered 20 times higher than the amount California currently considers safe for drinking water. The others had perchlorate rates five times higher than California's safety level.

Perchlorate is a contaminant that exists in the environment as a part of other compounds such as ammonium, potassium, or sodium perchlorate. Ammonium perchlorate is manufactured as an oxygen-adding component in solid fuel propellant for rockets, missiles, and fireworks.

In tests of perchlorate in supermarket produce, 18 percent of lettuce samples contained detectable levels of perchlorate, and an average serving of contaminated lettuce contained 4 times more perchlorate than the EPA says is safe in drinking water.

The source of the perchlorate, according to the EWG, is most likely the Colorado River, whose perchlorate-contaminated water irrigates more than 1.4 million acres in California and Arizona.

EWG’s tests on retail produce confirmed previous research on greenhouse-grown lettuce seedlings and field-grown lettuce, kale, and spinach.

"Our findings and the earlier tests show that toxic rocket fuel is not just a regional problem in areas where drinking water is contaminated, but a national concern for everyone who eats winter lettuce," said Renee Sharp, a senior analyst in EWG's California office and co-author of the report."

Perchlorate, the explosive component of rocket and missile fuel, can affect the thyroid gland’s ability to make essential hormones. For fetuses, infants and children, disruptions in thyroid hormone levels can cause lowered IQ, mental retardation, loss of hearing and speech, and motor skill deficits.

Perchlorate contaminates more than 500 drinking water sources in 20 states, serving well over 20 million people.

Among major contaminated sources is the Colorado River, which not only provides drinking water for Los Angeles, Phoenix, Las Vegas and other cities, but also irrigates 70 percent of the nation’s lettuce grown from October to March. Of the 15 leading lettuce-growing counties in the U.S., 10 have known or suspected sources of perchlorate pollution.

At the same time, while most of the perchlorate contamination nationwide comes from military bases or plants operated by federal defense contractors, the White House asked Congress to exempt defense facilities from a number of environmental regulations, including cleanup of toxic waste.

U.S. Sen. Barbara Boxer, D-Calif., and State Sen. Nell Soto, D-Ontario, each introduced bills that would require all past and present perchlorate polluters to disclose their use, method of disposal and history of leaks.

About Perchlorate

Concerns about perchlorate have been around since 1997.

Perchlorate interferes with iodide uptake into the thyroid gland. Because iodide is an essential component of thyroid hormones, perchlorate disrupts how the thyroid functions. In adults, the thyroid helps to regulate metabolism. In children, the thyroid plays a major role in proper development in addition to metabolism. Impairment of thyroid function in expectant mothers may impact the fetus and newborn and result in effects including changes in behavior, delayed development and decreased learning capability.

Changes in thyroid hormone levels may also result in thyroid gland tumors. EPA’s analysis of perchlorate toxicity is that perchlorate’s disruption of iodide uptake is the key event leading to changes in development or tumor formation.

According to the California Environmental Protection Agency, studies suggest that perchlorate disrupts thyroid hormone production, resulting in hypothyroidism and more rarely, thyroid tumors. The risk is greatest for pregnant women, children, and people who have health problems or compromised thyroid conditions.

EPA Drives Toward Perchlorate Standards

Recognizing the danger of perchlorate, the EPA has named the compound as a contaminant. The agency identifies routes of the toxin into the human body and sets standards for presumed contamination. Regulatory action continues to develop around environmental exposure to perchlorate on state and federal levels.