title: Early lifestage exposure and potential developmental susceptibility to tetrachloroethylene.
abstract: BACKGROUND
  Tetrachloroethylene, also known as perchloroethylene or "perc", is a highly volatile and lipophilic solvent widely used in dry cleaning, textile processing, and metal-cleaning operations. The limited epidemiological and toxicological data available for exposure to perc during developmental lifestages, as well as the evidence for critical windows of exposure, highlight early life as a period of potential susceptibility.
  
  
  METHODS
  A literature search was performed to identify all peer-reviewed epidemiological and toxicologial studies examining outcomes from early lifestage exposure to perc, and reviewed by developmental stage for both exposure and outcome.
  
  
  RESULTS
  Exposure scenarios to perc unique to early lifestages include transplacental and breast milk intake, along with inhalation, ingestion, or dermal exposure. Toxicokinetics factors that may influence early lifestage susceptibility to perc, along with existing physiologically based pharmacokinetic (PBPK) models, are described. Adverse outcomes examined include: reproductive outcomes examined prior to conception including reduced fertility, adverse effects on sperm, or altered reproductive hormones; prenatal outcomes examined after exposure prior to conception or prenatally including fetal death, birth defects, and decreased birth weight; postnatal outcomes examined after exposure prior to conception, prenatally, or during childhood including neurotoxicity, immunotoxicity, cancer, hepatotoxicity, congential anomalies and mortality; and adult schizophrenia examined after exposure prior to conception.
  
  
  CONCLUSIONS
  The limited evidence on early lifestage exposure to perc does not provide sufficient evidence of this sensitive period as being more or less important than exposure at a later lifestage, such as during adulthood. However, there are a number of adverse health effects observed uniquely in early lifestages, and increased sensitivity to visual system deficits is suggested in children. Other outcomes observed in adults may not have been adequately assessed in children to directly compare sensitivity.
authors.affiliation: National Center for Environmental Assessment, Office of Research and Development, US Environmental Protection Agency, Mailcode 8623-P, Washington, DC 20460, USA. brown.rebecca@epa.gov
authors.forename: Rebecca
authors.initials: R
authors.lastname: Brown Dzubow
authors.forename: Susan
authors.initials: S
authors.lastname: Makris
authors.forename: Cheryl
authors.initials: C
authors.lastname: Siegel Scott
authors.forename: Stanley
authors.initials: S
authors.lastname: Barone
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D004198:Disease Susceptibility; D004777:Environment; D004781:Environmental Exposure / Q000009:adverse effects; D004785:Environmental Pollutants; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D018811:Maternal Exposure; D008895:Milk, Human / Q000187:drug effects; D009369:Neoplasms / Q000139:chemically induced; D012559:Schizophrenia / Q000209:etiology; D013750:Tetrachloroethylene / Q000494:pharmacology* / Q000633:toxicity*; D016896:Treatment Outcome
chemical_list: D004785:Environmental Pollutants; D013750:Tetrachloroethylene