CHEMICAL COMMODITIES, INCORPORATED
OLATHE, JOHNSON COUNTY, KANSAS
The Chemical Commodities Inc. (CCI) site, which occupies about 1½ acres, is in a largely residential area of Olathe, Kansas. The facility was in operation from 1951 until 1989, and stored chemicals that were surplus, off-specification, recycled, or had exceeded their specified shelf life (1). Contamination for the site and the area includes a shallow groundwater plume of dissolved chlorinated solvents, air emissions of this plume through the soil, and heavy metal soil contamination (5). Past soil vapor and crawl space sampling indicate a potential for volatile compounds in the soil and groundwater to transport through soil as vapor into indoor air (1,3,4). Previous health consultations were completed (7, 8, 9) and concluded that warehouse and residential indoor air, outdoor air, soil, and sump water data were not expected to cause adverse health effects at the levels detected. A consistent recommendation throughout the previous health consultations has been to characterize seasonal variation of off-gassing soil, through the continued monitoring of indoor air. Previous health consultations with their individual recommendations are available from the Agency for Toxic Substances and Disease Registry (ATSDR). The Environmental Protection Agency (EPA) Project Manager for the CCI site requested that the Agency for Toxic Substances and Disease Registry (ATSDR) review December indoor air sampling results for homes adjacent to the CCI site to determine if contaminant levels are of public health concern (2).
The EPA collected residential indoor air samples in December 2001 to better characterizeseasonal variation. Residential indoor air was collected for twenty-four hours in 6 homes. Oneoutdoor air sample was collected for comparison (6). The major volatile contaminants in theCCI plume are trichloroethylene (TCE), tetrachloroethylene (PCE), trichloroethane (TCA) cis-1,2-dichloroethene (DCE), carbon tetrachloride and 1,1,2,2-perchloroethane (PCA) (5).Chloroform, methylene chloride, benzene, toluene, xylene and other chlorinated solvents werefound in the groundwater at lower levels (1).
It is possible for contaminants which volatilize, to travel through the air spaces in soil abovegroundwater and enter buildings. These volatile chemicals can collect in the home and exposedwellers. Many variables can influence the levels of volatile chemicals in the home from thesoil. Soil density, whether the soil is clay or sandy, can allow volatile chemicals to pass from acontaminant plume to the surface. House construction, like concrete slab or pier and beam can influence the travel of volatiles into the home.
Inhalation is an important pathway for human exposure to contaminants that exist as atmosphericgases or are adsorbed to airborne particles or fibers. Inhalation exposure to contaminants fromhazardous waste sites can occur as a result of direct release of gases and particles from an on-site facility, volatilization of gases from contaminated soils or water bodies, or resuspension of dustand particles from contaminated soil surfaces. Factors contributing to air exposure are inhalationvolume, temperature, altitude, background air quality, pulmonary quality, weight, height, and smoking.
The presence of contaminants in any media does not necessarily present a health hazard. Theamount of contaminant an individual is exposed to, as well as the duration of exposure, must betaken into account in order to determine if health effects would be expected. These two factorstogether define the exposure conditions and the dose of the chemical. The duration of exposureto a contaminant in a home can vary greatly. The duration would be the amount of time per day,or per week an individual spent in the home or contacting soil. Although many individualswork, go to school or leave the home for periods of time over the week, this may not always bethe case. Therefore, in an effort to protect all individuals, a full time exposure, 24 hours a day, isassumed in this evaluation. Additionally, when evaluating theoretical cancer risk, this full timeexposure is taken as a lifetime exposure of 70 years. Although it is extremely unlikely that anindividual will meet these conditions, the most conservative exposure scenario is chosen to be protective of public health.
ATSDR uses comparison values (CV's) to select which substances and environmental media at asite need additional evaluation to address possible health concerns. CV's are concentrations oramounts of substances in air, water, food, and soil that are unlikely, upon exposure, to causeadverse health effects based on current scientific literature. If the maximum detectedconcentration of a contaminant exceeds its specific CV, additional evaluation of potential healtheffects is necessary. Estimates of exposure to a contaminant by an individual (both child andadult) are calculated and compared with minimum risk levels (MRLs) if a contaminate is abovethe CV. ATSDR has established MRLs for exposures to many chemicals based on availablemedical, toxicological and epidemiologic data. The MRL is an estimate of daily humanexposure by a specified route and length of time to a dose of a chemical that is likely to bewithout a measurable risk of adverse, noncancerous effects. MRLs are established for a route ofexposure (breathing, ingestion, or dermal contact) and a duration (acute, intermediate or chronic). AcuteMRLs are for up to 14 days of exposure, intermediate MRLs are established for 14 - 365 days ofexposure, and chronic MRLs are established for exposure greater than 365 days. Informationused to establish MRLs often include studies of people exposed to chemicals in the workplace,and laboratory animal studies. There are uncertainties in applying both worker studies andanimal studies to the general population. Therefore, MRLs are often 100 to 1000 times lowerthan the level which may have resulted in a health effect. As such, the MRLs are conservativevalues below which no adverse health effects are expected.
ATSDR extensively reviews literature linking exposure to compounds with cancer. The lowestlevel of exposure documented to cause any form of cancer in humans or animals is reduced by asafety factor of 100,000, which simply means if 100,000 people were exposed to this amount ofcompound 24 hours, everyday of their lives for 70 years, 1 extra cancer case might be expectedabove the normal rate of cancer in that population, i.e. 1 case in 100,000 (or 1X10-6) abovenormal. The cancer risk evaluation guide (CREG) is the amount of compound at which theexcess cancer risk is 1X10-6. A detected compound exceeding this level does not mean thatcancer can be expected, rather that the level of the compound needs to be evaluated further bycalculations involving the amount of time a person is likely to be exposed and the amount of compound the person is exposed to. Also the amount of a chemical detected at any one time is arecording of the level at one point in time which does not show how the compound's levelfluctuates over the years. The chemical is more likely to fluctuate throughout a given timeperiod, so rarely is a person exposed to the same amount of chemical over a long period of time.This is also true for time exposed. Generally families do not spend 24 hours indoors for 70 years.Therefore, the model is designed to be very conservative and to protect sensitive populations.
Possible exposure to site-related air contaminants was evaluated at six homes near CCI property.Indoor air samples were taken for 24 consecutive hours. The samples were collected in apressurized metal cylinder (SUMMA© canister) and sent for laboratory analysis. Each airsample was analyzed for volatile chemicals. The 24-hour samples are an average airconcentration for that period of time. Contaminants detected included Freon 11 & 12; 1,1-Dichloroethene; cis-1,2-Dichloroethene; Chloroform; Carbon tetrachloride; Methylene chloride;Acetone; 2-Propanol; Ethanol; 2-Butanone; m,p-Xylene; o-Xylene; Benzene; 1,1,1-Trichloroethane; 1,2-Dichloro-ethane; Tetrachloroethene; Ethylbenzene; 1,2,4-Trimethylbenzene; Trichloroethene; andToluene. These contaminants were compared to CVs. Table 1 summarizes the compoundsdetected in indoor air samples at their maximum detected level.
Levels of contamination above CV's were directly compared to air minimal risk levels using thehighest levels detected. None of the contaminants exceeded MRL values, and therefore are notconsidered to present a public health hazard.
Benzene is a known carcinogen (causes cancer). Carbon tetrachloride; Chloroform; 1,2-Dichloroethane; and Methylene chloride are reasonably anticipated to all be carcinogens.Chloroform; Carbon tetrachloride; Methylene chloride; Benzene; and 1,2-Dichloroethane wereevaluated further for health effects because they exceeded CV's.
As with non-cancer health effects, calculations using the levels of contaminants found inresidential indoor air were performed. Exposure levels for carcinogens were determined to be farbelow levels that are known or believed to cause cancers, either in human or animal studies.Therefore, the ability for these exposures to result in increased cancer is highly unlikely, and arenot considered a public health hazard.
ATSDR recognizes that infants and children may be more vulnerable to exposures than adults incommunities faced with contamination of their air, water, soil, or food. As part of its ChildHealth Initiative, ATSDR is committed to evaluating children's special interests. Consideringexposure to indoor residential air at the CCI site, children may have an increased vulnerabilitydue to the following factors: 1) children weigh less than adults, resulting in higher doses ofchemical exposure relative to body weight, 2) the developing bodily systems of children cansustain permanent damage if toxic exposures occur during critical growth stages, 3) childrenhave a breathing zone lower to the ground and 4) children are more likely to have object tomouth contact. Similarly, the elderly may be susceptible due to changes in the body's ability todetoxify chemicals and repair damage which come with aging. As a conservative screening tool,the MRL is designed to account for these factors. When considering how well the experimentaldata can be applied to the general population, an uncertainty factor for human variability is usedin developing the comparison value. This uncertainty factor addresses the application of thecomparison value to sensitive populations, including children and the elderly, which may nothave been involved in the study population on which the comparison value is based. Thereforethe comparison values are considered protective of these sensitive populations. Although, thereare still many unknowns about the carcinogenic process and the bodies ability to defend againstit, the cancer estimates, are believed to be protective of the general population by theirconservative nature.
Contaminants found in indoor air samples of residences near the CCI facility are below levels expected to cause health effect and are not expected to pose a public health hazard.
1. ATSDR recommends air monitoring of homes near the CCI, Inc. site as the situation changesor as site related contaminants found in the shallow groundwater plume migrate under previously uncharacterized soil morphology.
|Detected indoor air contaminants||Maximum detected level ug/m3||1Comparison Value ug/m3||2Cancer comparison value|
|freon 11|| |
|freon 12|| |
|0.04 ug/m3 CREG|
|0.04 ug/m3 CREG|
|carbon tetrachloride|| |
|0.07 ug/m3 CREG|
|methylene chloride|| |
|benzene||4.4||150||0.1 ug/m3 CREG|
|1,2-dichloroethane||0.15||2430||0.04 ug/m3 CREG|
1 Comparison values (CV) represent levels above which chronic health effects may occur, unless noted by (#), in which case, the lowest intermediate or acute level was used for evaluation. CV's denoted with * are National Institutes of Safety and Health (NIOSH) values, see definitions.
2 See definitions.
LTJG Shawn Blackshear, M.S.
Health Service Officer, USPHS
Office of Regional Operations, Region 7
LCDR Robert Knowles, M.S., REHS
Superfund Assessment Branch
Division of Health Assessment and Consultation
Office of Regional Operations
- Adverse Health Effect:
- A change in body function or the structure of the cells that can lead todisease or health problems.
- Cancer Risk Evaluation Guide for 1 X 10 -6 excess cancer risk. Contaminants that exceed this value may increase risk of cancer over a lifetime of constant exposure to that level. A value over the CREG does not mean and increased cancer risk, rather it is a value that shows a compound must be evaluated further by the use of calculations to determine if an increased cancer risk is present.
- Minimal Risk Level. An estimate of daily human exposure--by a specified route andlength of time--to a dose of a chemical that is likely to be without a measurable risk ofadverse, noncancerous effects. An MRL should not be used as a predictor of adverse healtheffects.
- National Institute for Occupational Safety and Health. NIOSH's exposure limits aretypically based on worker exposure research and are expected to protect workers from healthhazards during an average exposure during working conditions. NIOSH exposure limits wereused when other health agencies did not have health related exposure values for certaincompounds.
- No Apparent Public Health Hazard:
- The category is used in ATSDR's Public HealthAssessment documents for sites where exposure to site-related chemicals may have occurredin the past or is still occurring, but the exposures are not at levels expected to cause adverse health effects.
- No Public Health Hazard:
- The category is used in ATSDR's Public Health Assessmentdocuments for sites where there is evidence of an absence of exposure to site-relatedchemicals.
- A line or column of air or water containing chemicals moving from the source to areas farther away. A plume can be a column or clouds of smoke from a chimney or contaminated underground water sources or contaminated surface water (such as lakes, ponds, and streams).
- Public Health Hazard:
- The category is used in ATSDR's Public Health Assessment documentsfor sites that have certain physical features or evidence of chronic, site-related chemical exposure that could result in adverse health effects.
- A compound that evaporates and becomes a vapor in the air. How quickly a compound becomes a vapor is measured by its vapor pressure.
- Groundwater Technology, Inc. Site Characterization Report Former Chemical Commodities,Inc.; 1996.
- Environmental Protection Agency. Note from Mary Peterson, EPA Remedial ProjectManager, to Denise Jordan-Izaguirre, ATSDR Senior Regional Representative: Request forHealth Consultation, Chemical Commodities, Inc. Site, Olathe, Kansas. Kansas City, Kansas.February 21, 2002.
- Final Report for Toxic Air Monitoring in Residences Near Chemical Commodities, Inc.Region VII Environmental Services Division, U.S. Environmental Protection Agency; 1989,November 13.
- Agency for Toxic Substances and Disease Registry. Health Consultation: ChemicalCommodities Inc.. April 30, 1996.
- Agency for Toxic Substances and Disease Registry. Site review and update for ChemicalCommodities, Inc. Olathe, Johnson County, Kansas. Atlanta: US Department of Health andHuman Services; 1996, December 24.
- Quality Assurance Project Plan for Removal Site Evaluation Activities at the ChemicalCommodities, Inc. Site, Olathe Kansas: Environmental Protection Agency, Region VIISuperfund Division; February 19, 2002.
- Agency for Toxic Substances and Disease Registry. Health Consultation: ChemicalCommodities, Incorporated. June 11, 2001.
- Agency for Toxic Substances and Disease Registry. Health Consultation: ChemicalCommodities, Incorporated. September 25, 2001.
- Agency for Toxic Substances and Disease Registry. Health Consultation: ChemicalCommodities, Incorporated. February 4, 2002.