Western region pesticide meeting air monitoring studies for agriculture urban interfaces
Sponsored Links
This presentation is the property of its rightful owner.
1 / 44

Western Region Pesticide Meeting Air Monitoring Studies for Agriculture-Urban Interfaces PowerPoint PPT Presentation


  • 55 Views
  • Uploaded on
  • Presentation posted in: General

Western Region Pesticide Meeting Air Monitoring Studies for Agriculture-Urban Interfaces. Carl A. Brown, Ph.D. Idaho Department of Environmental Quality. Outline. Purpose of study Background/Description of sites Preliminary Risk Screening Analysis Source identification 1, 3-DCP Wrap-up.

Download Presentation

Western Region Pesticide Meeting Air Monitoring Studies for Agriculture-Urban Interfaces

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Western Region Pesticide Meeting Air Monitoring Studies for Agriculture-Urban Interfaces

Carl A. Brown, Ph.D.

Idaho Department of Environmental Quality


Outline

Purpose of study

Background/Description of sites

Preliminary Risk Screening Analysis

Source identification

1, 3-DCP

Wrap-up


Treasure Valley Air Toxics Study

  • EPA Community Scale Air Toxics Monitoring Project

  • Goals:

    • Understand spatial and seasonal trends of air toxics in the Treasure Valley

    • Identify source categories

  • Number of individual contributors


Monitoring Locations

Meridian – St. Luke’s

Parma

Boise – Mt View School

Nampa - NNU

SE Boise – White Pine


Sampling and Analysis Methods

  • Metal/Trace Element Hazardous Air Pollutants

    • Quartz PM10 Hi-vol filters

    • Metals analysis by EPA IO-3.5 (ICP analysis)

  • Volatile Organic Carbon Compounds (VOCs)

    • Whole-air samples in evacuated Summa Cans

    • EPA Method 15A (GC/FID)

  • Carbonyls (aldehydes and ketones)

    • Sample adsorbed on DNPH cartridge

    • Analysis by EPA Method 11A (HPLC)


Air Toxics Study Period

Every 6th Day


Data Quality Assessment – Frequently Detected Species


Data Quality Assessment – Infrequently Detected Species


What is 1, 3 DCP?

  • Soil fumigant used mainly to control nematodes

    • Onions

    • Potatoes

    • Sugar beets

  • Trade name Telone marketed exclusively by Dow

  • State specific rules in CA limiting its use

  • Based on EPA pesticide renewal process a number of BMP have been implemented


Data Quality Assessment

  • % > MRL

  • Precision

  • Completeness

  • In order to characterize a pollutant… you need to first detect it…


Risk Screening Process

Remove species with low data quality

Determine maximum measured concentration

Compare maximum concentration to conservative benchmarks


Risk Screening Process

  • Compare to conservative benchmarks: Non-carcinogens

    • Hazard quotient > 0.1:

      • The ratio of the potential exposure to a substance and the level at which no adverse effects are expected.


Risk Screening Process

Compare to conservative benchmarks: Carcinogens

1 in a Million Cancer Risk:

A risk level of 1 in a million implies a likelihood that 1 person, out of a population of one million equally exposed people would contract cancer if exposed continuously (24 hours per day) to the specific concentration over 70 years (an assumed lifetime).


Risk Screening

After removing the compounds measured with a low confidence, the following species are the remaining contaminants of concern:

  • acetaldehyde

  • arsenic

  • benzene

  • cadmium

  • (cis- and trans-)1,3-dichloropropene

  • ethyl benzene

  • formaldehyde

  • manganese

  • methylene chloride


Carcinogenic Risk DriversMonitoring Site


Communication

  • Management

  • ISDA

  • UI Parma Research Center

  • IDHW

  • EPA


Source Identification Methods

  • Statistical “Receptor Modeling” methods

    • Principal Component Analysis – PCA

    • Positive Matrix Factorization – PMF

  • Temporal patterns

  • Correlations with other species/tracers

  • Seasonal-spatial trends

  • Experience with typical source categories

    • Other studies/literature

  • Source investigation


Identified Source Categoriesfor Contaminants of Concern


Data Comparisons

  • NATA: National Air Toxics Assessment

    • NATA provides inhalation cancer and non-cancer risks at the county and census tract level

  • Comparison to national monitoring data


National Air Toxics Analysis


Mobile


Mobile


Mobile

Mobile Source VOCs


Aldehydes


Aldehydes


Geologic/Wind Erosion


Geologic/Wind Erosion


(1,3-DCP)


(1,3-DCP)


Dispersion Modeling of 40 Acre 1,3 DCP Treatment, 1st 24-hours

  • Industrial Source Complex Area Source Model

  • Fall meteorology for Treasure Valley, Idaho

  • 1,3 DCP application rate: 177 lb/acre

  • Application Acreage: 40 acres

  • Total 1,3 DCP Flux (cis + trans)

    based on peak 24-hour

    loss of 7% of applied DCP: 1.62e-05 gm/m2-s


1,3 DCP Peak Flux, 7% loss in 1st 24-hrs


Modeled 1,3 DCP (g/m3) 40 acre Field 1st Day

  • Boise Airport meteorology for fall 2007.

  • Concentrations represent the highest 1 day total DCP concentration.

  • Peak concentration near the field is 367 ug/m3.

  • The maximum contour ridge extending toward the NW represents nighttime drainage wind directions when the air is stable.


Modeled 1,3 DCP (g/m3) 40 acre Field 1st Day


Modeled DCP concentration/distance

  • For Parma, the observations and model results are consistent for a 40 acre field about 200m to 2500m ( 1/8 to 1.5 miles away).

  • For NNU, the observations and the model results are consistent for a range of about 7500 to 9500 meters (or 4.6 to 6 miles away) approximately the distance from NNU to the agricultural areas surrounding Nampa.

  • Could be multiple fields at greater distances

  • Model results are reasonably consistent with the measurements


What about human health risk?

  • Conference call with pesticide risk assessor with EPA

    • 1, 3 DCP concentrations in the range of what EPA would have expected for rural/agricultural area and not a human health concern

  • Health Consultation with Dr. Kai Elgethun (IDHW)


Summary

  • Monitored air toxics at 5 sites across the Treasure Valley

  • Source attribution/risk screening

  • Most species at or below national median

  • 1, 3-DCP


Aldehydes


  • Login