Methylmercury (MeHg)
CASRN 22967-92-6 | DTXSID9024198
- IRIS Summary (PDF) (44 pp, 252.0 KB)
- Status: methylmercury (mehg) is in step 1 at this time.
IRIS Assessment Plan for Methylmercury (Scoping and Problem Formulation Materials)
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Overview
Citation
Background
The general population is predominantly exposed to methylmercury through consumption of contaminated fish and other seafood. Subsistence fishing communities and other populations with high dietary intakes of predatory fish species could be exposed to higher-than-average levels of methylmercury. Contaminated rice and rice-based food products, such as infant cereals, also can be a source of methylmercury exposure.
Methylmercury readily crosses the placenta and concentrates in cord blood. It is also transferred from mothers to children via breastmilk. The developing nervous system is particularly sensitive to methylmercury, so gestational, lactational, and other postnatal exposures are of concern.
History/Chronology
| Date | Description |
|---|---|
| Dec 1997 | EPA released the Mercury Study Report to Congress. |
| Oct 2000 | EPA released a draft document titled, Reference Dose for Methylmercury (NCEA-S-0930)" for a 30-day public review and comment. Following the review an external peer-review workshop was held to review the document. |
| Jan 2001 | EPA released the IRIS Summary for Methylmercury on the IRIS website and released the water quality criteria guidelines for states and authorized tribes. |
| Jan 2009 | EPA released the Methylmercury Implementation Guidance. |
| Apr 2010 | EPA released an update, referred to as the Methylmercury Implementation Guidance (Updated Apr 2010). |
| Apr 2019 | EPA released the IRIS Assessment Plan (IAP) for Methylmercury for public comment and review. [Federal Register Notice Apr 4, 2019] |
| May 2019 | EPA hosted a public science meeting to discuss preliminary meeting materials for methylmercury. |
Status
Download(s)
This download(s) is distributed solely for the purpose of pre-dissemination peer review under applicable information quality guidelines. It has not been formally disseminated by EPA. It does not represent and should not be construed to represent any Agency determination or policy.
- IRIS Assessment Plan for Methylmercury (Scoping and Problem Formulation Materials) (PDF) (20 pp, 493.2 KB, about PDF)
- IRIS Public Science Meeting (May 2019) - Methylmercury
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Document Related Link(s)
- Mercury Study Report to Congress (Final, 1997)
- EPA-HQ-ORD-2018-0655
- Reference Dose for Methylmercury (External Review Draft, 2000)
- IRIS Summary Update (2001) and EPA Guidelines for Methylmercury (2009 & 2010)
- Systematic Review Protocol for the Methylmercury (MeHg) IRIS Assessment (Preliminary Assessment Materials)
Federal Register Notices
Quick Check
Critical Effect Systems
Chemical Structure for
Methylmercury (MeHg)
