Effects of Wind Direction on Trace Metal Concentration

in Southeast Kansas

Sergio A. Guerra, Dennis D. Lane, Glen A. Marotz, Ray E. Carter, Richard W. Baldauf, Carrie M. HohlDepartment of Civil, Environmental, and Architectural

Engineering, University of Kansas

Introduction

Southeast Kansas supports the highest concentration of hazardous waste burners in the country 3 cement kilns 1 commercial hazardous waste incinerator

U.S. EPA sponsored the Southeast Kansas Health Study to investigate air quality and potential health effects from ambient air in the area (report available at http://www2.kumc.edu/ceoh/skhs/)

This study was a joint effort between the Department of Civil and Environmental Engineering at KU and the KU Medical Center

Scope

The environmental sampling element of the project included the determination of trace metal concentrations from PM2.5collected in Teflon filters in Southeast Kansas.Effects of spatial and temporal factors on

these concentrations were investigatedWind direction effects are of particular

interest

Air Quality Monitoring

March to October, 2000Sampling Sites in the cities of Chanute,

Coffeyville, Fredonia, and IndependenceAdditional Site in Labette CountySampling Site Design, Sampling and

Analysis Protocols According to EPA Guidelines

Sampling Area in Southeast Kansas

Fredonia

Site NameSite Code

Fredonia- Lincoln School FLS

Fredonia- South Farm FSF

Fredonia- South Mound FSM

Independence- Eisenhower School IES

Independence- Radio Tower IRT

Independence- East of River IER

Chanute- North Ash Grove CNA

Chanute- South Ash Grove CSA

Chanute- Elderly Care Center CEC

Labette County- Big Hill Lake LCL

Source-specific sites

Wichita windrose (1984-1992)

Data Collection- MiniVOL

Filters of PM2.5 samples from each sampling day were selected

Filters were digested and analyzed by ICP/MS for 20 metals

Data Analysis

Descriptive statistics were calculated for all trace metal concentrationsAnalyses of variance (anovas) were

performed on:Possible effects of sampling sitePossible effects of sampling date

Analogous non-parametric tests also performed to confirm anova results

Data Analysis

The effect of wind direction on PM concentrations was further investigated by performing a General Linear Model (GLM)Data was divided in four wind direction categories (from

NCDC);SouthNorthCalm/variableOther

The effect of the targeted sources was also analyzed by using the paired t-test and the analogous non-parametric test

Integrated Risk Information System (IRIS)

Mean Chromium conc. was found to exceed the 1 in 100,000 risk level

Mean and median arsenic conc. exceeded the 1 in 1,000,000 risk level

Mean cadmium conc. exceeded the 1 in 1,000,000

Metal Concentration (µg/m3) producing risk levels

1 in 10,000 1 in 100,000 1 in 1,000,000

Be 0.04 0.004 0.0004

Cr(VI) 0.006 0.0006 0.00006

As 0.02 0.002 0.0002

Cd 0.06 0.006 0.0006

Al, V, Fe, Co, Rb Not listed as hazardous air pollutants

Mn, Ni, Cu, Zn, Se, Mo, Ag, Sb, Ba,

Tl Not assessed under IRIS program

PbCarcinogen Assessment Group recommends

that numerical estimate not be used

Six metals were chosen for thorough analysisBerylliumChromiumArsenicCadmiumBariumLead

Results

Anova and Kruskal-Wallis analysis shows:Site is not a statistically significant factor for any metals

(95% confidence)Temporal factor was found to be statistically significant

for chromium, arsenic, cadmium, barium and lead

Temporal factor was further investigated through temperature, wind speed and atmospheric variables

Sampling dates were divided into North, South, calm/variable and other categoriesGLM was run to determine the effect of

site and wind direction; site and wind direction interaction Wind direction was significant for chromium,

barium, and lead at 95% confidence levelWind direction was significant for arsenic at

90% confidence level

Anova and Kruskal-Wallis tests were run on the database used for the GLMWind direction was not statistically significant for

beryllium, arsenic and cadmiumWind direction was statistically significant for chromium,

barium and lead Calm/variable winds produced highest chromium

concentrations North winds produced highest barium

concentrations South winds and calm/variable winds produced

the highest lead concentrations

Upwind versus downwind samples

The effect of selected sources was tested by applying the t-test and analogous non-parametric testData included upwind and downwind

samples for cities of Chanute, Independence and FredoniaDifferences between upwind and

downwind samples were not found statistically significant at the 95% level

Conclusions

Mean chromium concentration exceeded the 1 in 100,000 risk levelThough risk level is for Cr(VI)

Mean arsenic and cadmium concentrations exceeded the 1 in 1,000,000 risk level

Sampling site was not significant for beryllium, chromium, cadmium, arsenic, barium and lead

Sampling day was significant for all metals except beryllium

Conclusions…

Calm/ variable winds produced the highest chromium concentrations

Predominantly north winds produced the highest barium concentrations

Predominantly south and calm/variable winds produced the highest lead concentrations

No statistically significant differences were found between samples upwind and downwind from targeted sources