TCA in groundwater: Difference between revisions
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* TCA is absorbed from the gastrointestinal tract and 30 % from the lungs | * TCA is absorbed from the gastrointestinal tract and 30 % from the lungs | ||
* Chemical is rapidly distributed to all tissues via bloodstream | * Chemical is rapidly distributed to all tissues via bloodstream | ||
* Chronic toxicity | |||
** Reported in several studies for no toxicity, no excess cancers, no marked oncogenic effect, no effect on mortality or body weight | |||
** One study reported excess of leukemias in rats exposed to TCA | |||
* Only few weakly positive results for mutagenicity of TCA | * Only few weakly positive results for mutagenicity of TCA | ||
** These results can be explained by butylene oxide present in some commercial formulations of TCA | ** These results can be explained by butylene oxide present in some commercial formulations of TCA | ||
* No teratogenic effects in rodents exposed to TCA | * No teratogenic effects in rodents exposed to TCA | ||
* TCA is relatively nontoxic chemical | |||
* High dose of TCA can cause: | |||
** Narcosis | |||
** Mild organ pathology | |||
** Irritation of respiratory tract | |||
== Dose-Response assessment == | == Dose-Response assessment == | ||
Revision as of 10:48, 13 September 2006
Introduction to Environmental risk analysis - course
Groupwork
Mikko Pohjola
Juha Villman
James L. Byard: Hazard Assessment of 1,1,1-Trichloroethane in Groundwater
Identification of Hazard
In text: chapters 8 Toxicology & 9 Estimation of nontoxic dose
- TCA has been used as an industrial degreasing solvent
- TCA is absorbed from the gastrointestinal tract and 30 % from the lungs
- Chemical is rapidly distributed to all tissues via bloodstream
- Chronic toxicity
- Reported in several studies for no toxicity, no excess cancers, no marked oncogenic effect, no effect on mortality or body weight
- One study reported excess of leukemias in rats exposed to TCA
- Only few weakly positive results for mutagenicity of TCA
- These results can be explained by butylene oxide present in some commercial formulations of TCA
- No teratogenic effects in rodents exposed to TCA
- TCA is relatively nontoxic chemical
- High dose of TCA can cause:
- Narcosis
- Mild organ pathology
- Irritation of respiratory tract
Dose-Response assessment
In text: 8 Toxicology & 9 Estimation of nontoxic dose
- 15 minutes of vapor concentrations of TCA increasing from 0 to 2650 ppm
- Mild eye irritation at 1000 - 1100 ppm
- Throat irritation at 1900 - 2000 pm
- Lightheadedness at 2600 ppm
- Inability to stand at 2650 ppm
Exposure assessment
In text: 6 Exposure & 7 Determination of dose
Risk Characterization
In text: 10 Conclusions & 9 Estimation of nontoxic dose