California Environmental Protection Agency Department of Pesticide Regulation
AIR MONITORING NETWORK RESULTS FOR 2012
DRAFT July 2013 | SUMMARY
In February 2011, DPR implemented a multi-year statewide air monitoring network for measuring pesticides in various agricultural communities. This new pesticide Air Monitoring Network (AMN) is the first multi-year air monitoring study conducted by DPR. The goals of the AMN are to provide data that assists in assessing potential health risks, developing measures to mitigate risks, and measuring the effectiveness of regulatory requirements. This report is the 2nd volume of this study and contains AMN results from January 1, 2012 to December 31, 2012.
DPR monitored a total of 33 pesticides and 5 pesticide breakdown products in three communities. Pesticides monitored in the AMN were selected based primarily on potential health risk. Higher-risk pesticides were prioritized and targeted for monitoring. Higher-risk pesticides were identified based on higher use, higher volatility, and higher toxicity. DPR evaluated 226 communities in California as candidates for inclusion in the network. DPR selected one site each in Salinas (Monterey County), Shafter (Kern County), and Ripon (San Joaquin County) for the AMN based on pesticide use, demographic data, and availability of other exposure and health data.
One 24-hour sample was collected each week at each of the three sites. The starting day varied each week with the actual dates being randomly selected. Sampling start times were left to the discretion of the field sampling personnel, but they always started anywhere from 9:00 a.m. to 2:00 pm. No state or federal agency has established health standards for pesticides in air. Therefore, DPR developed health screening levels for the monitored pesticides to place the results in a health-based context. The health screening level is the calculated air concentration based on a chemical's toxicity that is used to evaluate the possible health effects of exposure to the chemical. Although screening levels are not regulatory standards, they can be used to evaluate air monitoring results and determine if a more detailed assessment is warranted.
Overall, 94.5 % of the 6,002 analyses (number of samples times the number of chemicals analyzed) resulted in no detectable concentrations. Only 331 (5.5%) of the analyses had detectable (trace or quantifiable) concentrations, and 1.3% of the analyses had quantifiable concentrations. Quantifiable detections refer to concentrations above the LOQ for their respective pesticide. Fourteen of the 33 pesticides and 5 pesticide breakdown products monitored by DPR were not detected.
Of the 33 pesticide and 5 breakdown products included in the AMN, 24 were detected in at least one sample. However, all air concentrations were low relative to the screening levels. None of the pesticides exceeded their screening levels for any of the exposure periods, indicating low health risk to the people in these communities. Nine of the 11 pesticides (including three breakdown products) detected at quantifiable concentrations in the AMN were either fumigants (1,3-dichloropropene, carbon disulfide, methyl bromide, and MITC) or organophosphate insecticides (chlorpyrifos + OA, DDVP, diazinon OA, and malathion OA). Diuron and EPTC were also detected at quantifiable concentrations.