Worker's Exposure to Common Pesticides could be a Risk.

An insecticide used on corn and other U.S. crops poses health risks to workers who mix and apply it and also can contaminate drinking water, according to a U.S. Environmental Protection Agency report released this week.

The report is an update, based on new research, to a 2011 assessment of the health impacts of the pesticide chlorpyrifos (pronounced KLOR - pie -ra - phos), which remains one of the most commonly applied organophosphate pesticides. Although it has been banned from household use for over a decade, the pesticide is still being used on some golf courses and fruit and nut trees as well as corn and soybeans.

These findings could lead to more restrictions for worker health and water supply as the pesticide is subject to its registration review. This licensing process, which the EPA requires of pesticides, may be required by the EPA.

The industry maintains that chlorpyrifos can be safely used at the current levels in the environment. This is a great benefit for farmers. However, some environmental groups claim that restrictions on the use of chlorpyrifos will not be enough to protect human health.

"The science on health impacts - together with many personal stories -overwhelmingly supports the need for a phase out," said Margaret Reeves, a senior scientist at the Pesticide Action Network, in a statement. The Natural Resources Defense Council and Pesticide Action Network North American urged the EPA in 2007 to end all chlorpyrifos use.

The EPA mandated that schools and homes have buffers in order to lessen their exposure to radiation. According to the EPA, approximately 10 million pounds of pesticides are used annually in agriculture throughout the United States.

The EPA stated that they were concerned about workers mixing, loading and applying chlorpyrifos at agricultural and non-residential locations. "We also worry about workers who are exposed to areas treated with chlorpyrifos even if their work does not involve the use of chlorpyrifos products."

It did not identify any other risks related to food and airborne contamination. It cited the latest U.S. Department of Agriculture data that found "no concerns for chlorpyrifos in food, with the pesticide detected in less than 1 [percent] of samples."

However, researchers believe inhalation is likely a major exposure route for people living near heavily treated fields, said Janie Shelton, an epidemiologist who led a study linking chlorpyrifos to autism in babies born to moms near treated fields in farm-heavy Northern California last year.

Shelton explained that while this is likely to be a sub-clinical exposure, it could have an impact on the baby's health.

Shelton explained that chlorpyrifos, which is a neurotoxin, prevents nerve synapses from ceasing activity and causes over-stimulation. Chlorpyrifos has been implicated in birth defects and low birth weights. It also causes impaired brain development and disrupts the hormones.

According to her, the risk of pesticide exposure for fetuses is much greater.

Shelton explained that adult humans have an enzyme which can break down organophosphates, such as chlorpyrifos. It is something that comes on-line only after birth. Babies in the womb do not have this metabolizing enzyme.

"If they were exposed to a neurotoxin, it would take much higher levels to observe effects." The EPA didn't respond to requests for comment.

Even though household bans have been lifted, evidence indicates that some people still are exposed. A study of Northern California families and floor wipe samples last year found that 99 percent of floor wipes and 65 percent of study participants had some chlorpyrifos in them.

Shelton stated, "We are aware there is enough reason to ban residential use due to neurodevelopmental impairments of children." "I see reason to be concerned [with the continued use].

A spokesperson for Dow AgroSciences, which manufactures chlorpyrifos, noted that the EPA's announcement is part of a revision, not the final assessment and that "no pest control product has been more thoroughly tested."

Nichelle Harriott (staff scientist, Beyond Pesticides) said there was mounting evidence that chlorpyrifos is "unacceptable risk to workers" and the environment.

She said that "they [the EPA] need to be working towards getting the chemical off of the market. That is the only acceptable method to protect human- and environmental health."

The new announcement is subject to a 60 day comment period. Additionally, the EPA will release a report later in the year on the impact of chlorpyrifos on endangered species.