Is Methylmercury chloride safe for babies and kids?
Context-dependent for kidsNot medical or professional safety advice, and not a substitute for a qualified clinician — consult one. Full disclaimer →
(Babies-specific data is limited; this page draws from human pregnant context.) Pregnancy alters the metabolism and distribution of Methylmercury chloride, potentially increasing fetal exposure. The developing embryo/fetus is vulnerable during organogenesis (weeks 3-8) and neurological development. Placental transfer should be assumed.
What is methylmercury chloride?
The IUPAC name is Chloromethylmercury.
Also known as: Chloromethylmercury, Methylmercuric chloride, chloro(methyl)mercury, Mercury methyl chloride.
- IUPAC name
- Chloromethylmercury
- CAS number
- 115-09-3
- Molecular formula
- CH3HgCl
- Molecular weight
- 251.09 g/mol
- SMILES
- C[Hg]Cl
- PubChem CID
- 409301
Risk for babies
Context-dependentPregnancy alters the metabolism and distribution of Methylmercury chloride, potentially increasing fetal exposure. The developing embryo/fetus is vulnerable during organogenesis (weeks 3-8) and neurological development. Placental transfer should be assumed.
No specific reproductive toxicity data identified, but pregnancy-specific safety data is limited for most chemicals. Precautionary minimization of exposure is recommended.
Risk for pregnant and nursing people
Context-dependentPregnancy alters the metabolism and distribution of Methylmercury chloride, potentially increasing fetal exposure. The developing embryo/fetus is vulnerable during organogenesis (weeks 3-8) and neurological development. Placental transfer should be assumed.
No specific reproductive toxicity data identified, but pregnancy-specific safety data is limited for most chemicals. Precautionary minimization of exposure is recommended.
Regulatory consensus
9 regulatory and scientific bodies have classified Methylmercury chloride. The classifications differ — that's the data.
| Agency | Year | Classification | Notes |
|---|---|---|---|
| EPA | — | — | |
| IARC | — | — | |
| IARC | 1993 | Group 2B — Methylmercury compounds (possibly carcinogenic to humans) | IARC Monograph Vol. 58. Inadequate human evidence; sufficient evidence in experimental animals for methylmercury chloride. |
| Minamata Convention | 2013 | Treaty on Mercury — controls on supply, trade, products, processes, releases | Multilateral environmental agreement covering mercury and mercury compounds; entered into force 2017; 140+ parties. |
| US EPA | 2001 | RfD 0.1 µg/kg-day — methylmercury | IRIS chronic reference dose derived from Faroe Islands neurodevelopmental cohort. Basis for FDA/EPA fish-consumption advisories. |
| Health Canada | 2000 | CEPA Schedule 1 Toxic Substance — Mercury and its compounds | Mercury and its compounds on Schedule 1; Canada Mercury Strategy and Products Containing Mercury Regulations. |
| EFSA | 2012 | TWI 1.3 µg/kg bw/week — methylmercury | EFSA CONTAM Panel scientific opinion on mercury and methylmercury in food (EFSA Journal 2012;10(12):2985). |
| WHO | 2003 | PTWI 1.6 µg/kg bw/week — methylmercury (JECFA) | Joint FAO/WHO Expert Committee on Food Additives provisional tolerable weekly intake; basis for international fish-consumption guidance. |
| MHLW | 2003 | Maximum residue limit — methylmercury in fish (0.3 ppm) | Japan Ministry of Health, Labour and Welfare; legacy of Minamata disease (1956 onward) drove early adoption of methylmercury-specific food limits. |
Regulators apply different standards of evidence — animal-data weighting, exposure-pattern assumptions, epidemiological power thresholds — which is why two scientific bodies can review the same data and reach different conclusions. The disagreement is the data.
Where kids encounter methylmercury chloride
- laboratory settings
- research institutions
- aquatic food chains
- fish tissue
Safer alternatives
Lower-risk approaches that achieve a similar outcome to Methylmercury chloride:
-
Thimerosal-free vaccine preservatives (2-phenoxyethanol)
Trade-offs: Narrower antimicrobial spectrum. Single-dose vials eliminate need for preservative.Relative cost: 1.2× (single-dose vials 3-5×)
Frequently asked questions
What products contain methylmercury chloride?
Methylmercury chloride appears in: laboratory settings; research institutions; aquatic food chains.
Why do regulators disagree about methylmercury chloride?
Methylmercury chloride has been classified by 9 agencies including EPA, IARC, IARC, Minamata Convention, US EPA, with differing conclusions. Regulators apply different standards of evidence (animal data weighting, exposure-pattern assumptions, epidemiological power thresholds), which is why two scientific bodies can review the same data and reach different conclusions. See the regulatory consensus table on this page for the full picture.
See Methylmercury chloride in the baby app
Look up products containing methylmercury chloride, compare to alternatives, and explore the full data record.
Open in baby View raw API dataSources (1)
- ATSDR Toxicological Profile — CAS 115-09-3 — reference
Reference data, not professional advice. Aggregates publicly available regulatory and scientific data; not a substitute for medical, pediatric, legal, or regulatory advice. Why we built ALETHEIA →