The weeks shown in color represent the start and end points of chemical exposure for each study.

Study Results Study Details References

Results for Dioxin (TCDD)

Decreased relative thymus weight and thymic cellularity on gestational day 19 at dose of 3.0 μg/kg only; multiple phenotypic alterations in thymocytes on gestational day 19 and post-natal day 1, mostly at higher dose

Subjects: F344 rats

Chemical: Dioxin (TCDD)

Low doses tested: 1.0 or 3.0 μg/kg bw

Route of administration: dissolved in corn oil and delivered through gavage

Exposure duration: gestational day 14 – single dose (comparable to human prenatal development from approximately day 1 of week 6 to day 1 of week 7)

Age of measurement: gestational day 19 and post-natal day 1

Reference [PubMed Link]
Gehrs BC, Riddle MM, Williams WC, Smialowicz RJ. 1997. Alterations in the developing immune system of the F344 rat after perinatal exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin .I. Effects on the fetus and the neonate. Toxicology 122(3):219-228.
Study Results Study Details References

Results for Dioxin (TCDD)

Decreased thymic cellularity and altered percentage of thymocytes, particularly in pups cross-fostered for both perinatal and lactational exposure.

Subjects: F344 rats

Chemical: Dioxin (TCDD)

Low doses tested: 1.0 μg/kg bw

Route of administration: dissolved in corn oil and delivered through gavage

Exposure duration: gestational day 14 – single dose (comparable to human prenatal development from approximately day 1 of week 6 to day 1 of week 7)

Age of measurement: 1, 2 and 3 weeks of age

Reference [PubMed Link]
Gehrs BC, Riddle MM, Williams WC, Smialowicz RJ. 1997. Alterations in the developing immune system of the F344 rat after perinatal exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin .II. Effects on the pup and the adult. Toxicology 122(3):229-240.
Study Results Study Details References

Results for Dioxin (TCDD)

Decreased relative thymus weight in males

Subjects: F344 rats

Chemical: Dioxin (TCDD)

Low doses tested: 3.0 μg/kg bw

Route of administration: dissolved in corn oil and delivered through gavage

Exposure duration: gestational day 14 – single dose (comparable to human prenatal development from approximately day 1 of week 6 to day 1 of week 7)

Age of measurement: 14 to 17 weeks of age

Reference [PubMed Link]
Gehrs BC, Riddle MM, Williams WC, Smialowicz RJ. 1997. Alterations in the developing immune system of the F344 rat after perinatal exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin .II. Effects on the pup and the adult. Toxicology 122(3):229-240.
Study Results Study Details References

Results for Dioxin (TCDD)

Suppressed delayed-type-hypersensitivity response to BSA in males at 4 and 14 months at 1.0 μg/kg and at 14 months only at 0.1 and 0.3 μg/kg; also suppressed response in females at 14 months at 0.3 and 1.0 μg/kg

Subjects: F344 rats

Chemical: Dioxin (TCDD)

Low doses tested: 0.1, 0.3 or 1.0 μg/kg bw

Route of administration: delivered orally

Exposure duration: gestational day 14 – single dose (comparable to human prenatal development from approximately day 1 of week 6 to day 1 of week 7)

Age of measurement: 4 and 14 months of age

Reference [PubMed Link]
Gehrs BC, Smialowicz RJ. 1999. Persistent suppression of delayed-type hypersensitivity in adult F344 rats after perinatal exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin. Toxicology 134(1):79-88.
Study Results Study Details References

Results for Dioxin (TCDD)

Suppressed delayed-type-hypersensitivity response to BSA in males at 4, 8 and 19 months and in females at 4 months

Subjects: F344 rats

Chemical: Dioxin (TCDD)

Low doses tested: 3.0 μg/kg bw

Route of administration: delivered orally

Exposure duration: gestational day 14 – single dose (comparable to human prenatal development from approximately day 1 of week 6 to day 1 of week 7)

Age of measurement: 4, 8, 12 and 19 months of age

Reference [PubMed Link]
Gehrs BC, Smialowicz RJ. 1999. Persistent suppression of delayed-type hypersensitivity in adult F344 rats after perinatal exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin. Toxicology 134(1):79-88.
Study Results Study Details References

Results for Dioxin (TCDD)

Suppressed delayed-type-hypersensitivity response to KLH in 4 month old males and to BSA in 5 month old males

Subjects: F344 rats

Chemical: Dioxin (TCDD)

Low doses tested: 3.0 μg/kg bw

Route of administration: delivered orally

Exposure duration: gestational day 14 – single dose (comparable to human prenatal development from approximately day 1 of week 6 to day 1 of week 7)

Age of measurement: 4 and 5 months of age

Reference [PubMed Link]
Gehrs BC, Smialowicz RJ. 1999. Persistent suppression of delayed-type hypersensitivity in adult F344 rats after perinatal exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin. Toxicology 134(1):79-88.
Study Results Study Details References

Results for Dioxin (TCDD)

Significantly decreased thymus/body weight ratios and thymic cellularities on phenotypic analysis

Subjects: F344 rats

Chemical: Dioxin (TCDD)

Low doses tested: 3.0 μg/kg bw

Route of administration: delivered orally

Exposure duration: gestational day 14 – single dose (comparable to human prenatal development from approximately day 1 of week 6 to day 1 of week 7)

Age of measurement: 5 months of age

Reference [PubMed Link]
Gehrs BC, Smialowicz RJ. 1999. Persistent suppression of delayed-type hypersensitivity in adult F344 rats after perinatal exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin. Toxicology 134(1):79-88.
Study Results Study Details References

Results for Dioxin (TCDD)

Decreased relative spleen weight for wild type and AhRKO mice at 21 days of age.

Subjects: C57BL/6 mice

Chemical: Dioxin (TCDD)

Low doses tested: 5.0 μg/kg/bw

Route of administration: dissolved in corn oil and delivered orally

Exposure duration: gestational day 13 – single dose (comparable to human prenatal development from approximately day 1 of week 6 to day 1 of week 7)

Age of measurement: 21, 35, and 90 days of age

Reference [PubMed Link]
Lin TM, Ko K, Moore RW, Buchanan DL, Cooke PS, Peterson RE. 2001. Role of the aryl hydrocarbon receptor in the development of control and 2,3,7,8-tetrachlorodibenzo-p-dioxin-exposed male mice. Journal of Toxicology and Environmental Health-Part a 64(4):327-342.
Study Results Study Details References

Results for Dioxin (TCDD)

Decreased relative thymus weight for wild type mice at 21, 35, and 90 days of age, and for AhRKO type mice at 35 days of age

Subjects: C57BL/6 mice

Chemical: Dioxin (TCDD)

Low doses tested: 5.0 μg/kg/bw

Route of administration: dissolved in corn oil and delivered orally

Exposure duration: gestational day 13 – single dose (comparable to human prenatal development from approximately day 1 of week 6 to day 1 of week 7)

Age of measurement: 21, 35, and 90 days of age

Reference [PubMed Link]
Lin TM, Ko K, Moore RW, Buchanan DL, Cooke PS, Peterson RE. 2001. Role of the aryl hydrocarbon receptor in the development of control and 2,3,7,8-tetrachlorodibenzo-p-dioxin-exposed male mice. Journal of Toxicology and Environmental Health-Part a 64(4):327-342.
Study Results Study Details References

Results for Dioxin (TCDD)

Decreased contact hypersensitivity response (CHS) for males and females challenged at 7 days of age with topical application of 2,4-dinitrofluorobenzene (DNFB) applied to ventral and dorsal surfaces of right pinna at 2, 4, and 6 months of age at 1.0 and 3.0 μg/kg; increased total cellularity in vehicle control draining lymph node in females at 6 months of age at 1.0 μg/kg; increased percent of CD45RChi/CD4+ lymphocytes in draining nodes in females for both DNFB challenged and vehicle control challenged lymph nodes at 6 months of age at 3.0 μg/kg

Subjects: Fisher 344 rats

Chemical: Dioxin (TCDD)

Low doses tested: 1.0 or 3.0 μg/kg bw

Route of administration: dissolved in corn oil and delivered through gavage

Exposure duration: gestational day 14 – single dose (comparable to human prenatal development from approximately day 1 of week 6 to day 1 of week 7)

Age of measurement: 1 day through 6 months

Reference [PubMed Link]
Walker DB, Williams WC, Copeland CB, Smialowicz RJ. 2004. Persistent suppression of contact hypersensitivity, and altered T-cell parameters in F344 rats exposed perinatally to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Toxicology 197(1):57-66.
Study Results Study Details References

Results for Dioxin (TCDD)

Induction of CYP1A1 mRNA at the highest dose at 5 days, decreasing with age

Subjects: Holtzman rats

Chemical: Dioxin (TCDD)

Low doses tested: 0.0125, 0.050,0.2 or 0.8 μg/kg bw

Route of administration: dissolved in corn oil and delivered through gavage

Exposure duration: gestational day 15 – single dose (comparable to human prenatal development from approximately day 1 of week 6 to day 1 of week 7)

Age of measurement: birth through adulthood

Reference [PubMed Link]
Nohara K, Fujimaki H, Tsukumo S, Ushio H, Miyabara Y, Kijima M, Tohyama C, Yonemoto J. 2000. The effects of perinatal exposure to low doses of 2,3,7,8-tetrachlorodibenzo-p-dioxin on immune organs in rats. Toxicology 154(1-3):123-133.
Study Results Study Details References

Results for Dioxin (TCDD)

Accentuated fever in response to lipopolysaccharide endotoxin

Subjects: Long-Evans rats

Chemical: Dioxin (TCDD)

Low doses tested: 1.0 μg/kg

Route of administration: delivered through gavage

Exposure duration: gestational day 15 – single dose (comparable to human prenatal development from approximately day 1 of week 6 to day 1 of week 7)

Age of measurement: 3 months of age through adulthood

Reference [PubMed Link]
Gordon CJ, Miller DB. 1998. Thermoregulation in rats exposed perinatally to dioxin - core temperature stability to altered ambient temperature, behavioral thermoregulation, and febrile response to lipopolysaccharide. Journal of Toxicology & Environmental Health. Part A 54(8):647-662.
Study Results Study Details References

Results for Dioxin (TCDD)

Increased percentage of neutrophils in blood at seven days after weaning; increased tumor development following PYB6 tumor cell injection.

Subjects: B6C3F1 Hybrid mice

Chemical: Dioxin (TCDD)

Low doses tested: 1.0 μg/kg bw

Other doses tested: 5.0 or 15.0 μg/kg bw

Route of administration: dissolved in corn oil and delivered orally

Exposure duration: gestational day 14 – additional doses at 1, 7, and 14 days of age (comparable to human prenatal development from approximately day 1 of week 6 to beyond birth)

Age of measurement: 2 through 21 days of age

Reference [PubMed Link]
Luster MI, Boorman GA, Dean JH, Harris MW, Luebke RW, Padarathsingh ML, Moore JA. 1980. Examination of bone marrow, immunologic parameters and host susceptibility following pre- and postnatal exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Int J Immunopharmacol 2(4):301-10.
Study Results Study Details References

Results for Dioxin (TCDD)

Decreased relative thymus weight in males exposed via lactation and via both in utero and lactation, and in females exposed via both in utero and lactation

Subjects: Holtzman rats

Chemical: Dioxin (TCDD)

Low doses tested: 1.0 μg/kg bw; cross-fostered

Route of administration: dissolved in corn oil and delivered orally

Exposure duration: gestational day 15 – single dose (comparable to human prenatal development from approximately day 1 of week 6 to day 1 of week 7)

Age of measurement: 21 days of age

Reference [PubMed Link]
Nishimura N, Yonemoto J, Nishimura H, Ikushiro S, Tohyama C. 2005. Disruption of thyroid hormone homeostasis at weaning of holtzman rats by lactational but not in utero exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin. Toxicol Sci 85(1):607-614.