ERF of dioxin
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ERF of dioxin describes quantitative relationships between exposure to polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans (PCDD/Fs), and polychlorinated biphenyls (PCBs) and several health effects such as cancer, developmental defects and others. It assumed that effects are mediated via the Ah receptor and that toxic equivalencies (TEFs)) apply.
Question
What are quantitative relationships between exposure to dioxin (a common name for polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans (PCDD/Fs), and polychlorinated biphenyls (PCBs)) and several health impacts including
- remaining lifetime cancer risk and
- developmental defects in molar teethR↻
Answer
Rationale
Dioxins are a group of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs). They are persistent environmental contaminants that accumulate in the human body. Their elimination half-life is quite high (~7 years). 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is the most toxic PCDD/Fs congener, and it is classified as a known human carcinogen by the International Agency for Research on Cancer (IARC).
- Health effects related to long-term exposure
- impairment of the immune system
- impairment of the developing nervous system
- impairment of the endocrine system
- impairment of reproductive functions
- increased cancer risk
Summary
- Human health effects caused by dioxins
Dioxins are persistent environmental pollutants and they accumulate in the food chain. Dioxins cause a large variety of effects in laboratory animals. They are carcinogenic at large doses, and they also cause developmental defects. The evidence of human effects has been more limited, because the exposure levels have been much lower than in animal tests. However, an increased cancer risk has been observed after high industrial occupational exposures. In addition, mild tooth mineralisation defects have been observed in children in Finland, even after typical exposures of the 1980's. Children are exposed to dioxins mostly via mother's milk. The dioxin levels have been decreasing since then, and no tooth defects have been observed at the current exposure levels.
<t2b index="Exposure agent,Trait,Response metric,Exposure route,Exposure metric,Exposure unit,ERF parameter,Scaling,Observation" locations="Threshold,ERF" desc="Description" unit="-"> TEQ|Cancer, total|Lifetime probability|Ingestion|Intake|pg /kg /d|CSF|BW|0|0.000156|US EPA. From ERF of dioxin: 156000 (mg/kg/d)^-1 logTEQ|Developmental dental defects incl. agenesis|Yes/No according to "Developmental Defects of Enamel Index" |Ingestion etc. (as it was in Seveso)|log(TCDD serum concentration+1)|ng/kg in fat|ERS|None|0|0.26 +- 0.12|Alaluusua et al. 2004; PL Gradowska PhD thesis 2013. From ERF of TCDD. Resulting distribution based on one simulation. Weibull(alfa=0.2925,beta=2.192) logTEQ|Tooth defect|Yes/No according to "Developmental Defects of Enamel Index" |Placenta and mother's milk|log(TCDD serum concentration+1)|log(pg/g in fat)|ERS|None|0|0:0.06:0.12|Alaluusua et al. 2004 data with PL Gradowska PhD thesis 2013 approach but we used the response function y = k x + b (see below) TEQ|Dental defect|Yes/No according to "Developmental Defects of Enamel Index" |Placenta and mother's milk|Ingestion|pg/d|ERS|None|0|0.001382|Alaluusua et al. 1996 TEQ|Cancer|Morbidity|Ingestion|Intake|pg /kg /d|UR|BW|0|0.000032; 0.000035; 0.00016|From ERFs of environmental pollutants TEQ|Dioxin recommendation|Tolerable daily intake|Ingestion|Intake|pg /kg /d|T
See also
References
- Is the fear of dioxin cancer more harmful than dioxin? Jouko Tuomisto, Jouni T. Tuomisto: Toxicology Letters 2012.
- Alaluusua et al ETAP 1996: Polychlorinated dibenzo-p-dioxins and dibenzofurans via mother's milk may cause developmental defects in the child's teeth.
- Lancet. 1999 Jan 16;353(9148):206.
Developing teeth as biomarker of dioxin exposure. Alaluusua S, Lukinmaa PL, Torppa J, Tuomisto J, Vartiainen T.
- Mocarelli et al EHP 2008: Dioxin Exposure, from Infancy through Puberty, Produces Endocrine Disruption and Affects Human Semen Quality
- Alaluusua et al 2004: Developmental dental aberrations after the dioxin accident in Seveso.
- Crump et al. 2003. Meta-analysis of dioxin-cancer dose-response for three occupational cohorts. Environmental Health Perspectives 111 (5), 681-687.
- Kiviranta et al. Chemosphere. 2005 Aug;60(7):854-69.
- Kogevinas 2001. Human health effects of dioxins: cancer, reproductive and endocrine system effects. Human Reproduction Update 7 (3), 331-339.
- Tuomisto JT et al. Int J Cancer. 2004 Mar 1;108(6):893-900.
- Tuomisto et al. 1999. Synopsis on dioxins and PCBs. Publications of the National Public Health Institute B17/1999.
- van Leeuwen FX et.al. Chemosphere. 2000 May-Jun;40(9-11):1095-101.