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DPR 2013 Air Monitoring Shows Most Pesticides Well Below Health Screening Levels

Contact: Charlotte Fadipe
916-445-3974 |
September 23, 2014 (14-10)

SACRAMENTO – For the third year in a row, the California Department of Pesticide Regulation (DPR) air monitoring in various California rural agricultural communities shows that the majority of the monitored pesticides were found well below levels that indicate a health concern or need further evaluation.

"DPR has created the nation's only regulatory pesticide air monitoring network to capture data that helps guide our regulatory process," said DPR Director Brian Leahy. "It is a robust process that California can be proud of."

DPR's air monitoring network, was established to expand DPR's knowledge of the potential health risks of long-term exposure to pesticides. DPR scientists sought more accurate estimates of health risks based on long-term exposure rather than extrapolation from short-term monitoring data to help them determine if additional protective measures are needed.

In 2013, as part of its commitment to statewide air monitoring, DPR monitored 32 pesticides and five pesticide breakdown products in three California communities: Salinas (Monterey County), Shafter (Kern County) and Ripon (San Joaquin County).

These communities, part of the DPR air monitoring network (AMN), were selected from a list of 226 communities based on pesticide use on surrounding farmland and demographics, including the percentage of children, the elderly and farmworkers in the local population.

The pesticides were selected based on their potential health risks and the amount used. They include all the major fumigants, as well as chlorpyrifos.

Overall, the AMN 2013 report found that 92.9 per cent of the 6,033 analyses (number of samples times the number of chemicals analyzed) resulted in no detectable concentrations.

Other key findings include:

  • Of the 32 pesticides and five breakdown products that were monitored, 13 could not be detected at all and 10 were only detected at trace levels.
  • The pesticides detected the most often were chlorothalonil, chlorpyrifos and MITC. They were found at all three locations about 30 percent of the time, at air concentrations that were low relative to the screening levels.
  • For 2013, nearly all measured pesticide air concentrations were less than DPR's regulatory targets* or screening levels **. Chloropicrin was detected slightly above a DPR screening level. 1,3-D did not exceed a DPR screening level. However 1,3-D was detected at a level, that if continued for 70 years, would be above a DPR regulatory target. It is not unusual to see slight variances in annual data and these may be caused by a number of factors. Variances in annual data over a few years do not necessarily indicate a health hazard. DPR has taken action to reduce exposures to 1,3-dichloropropene and is proposing action on chloropicrin.

California is the only state that monitors air as part of its continuous evaluation of pesticides to ensure the protection of workers, public health and the environment. This includes conducting field studies to monitor exposure to workers and to measure how pesticides move and break down in air, soil and water. DPR uses this information to decide if further regulatory measures are necessary.

* Screening level is a level set by DPR to determine if a more detailed evaluation is warranted to assess a potential health risk.
** Regulatory target is the exposure level that DPR has determined unlikely to cause adverse health effects.