Mercury Salts, Inorganic

CASRN Various

  • Status: Mercury Salts, Inorganic is in step 1 at this time.

IRIS Assessment Plan for Inorganic Mercury Salts (Scoping and Problem Formulation Materials)


EPA announces the availability of the IRIS Assessment Plan for Inorganic Mercury Salts (Scoping and Problem Formulation Materials) for a 30-day public comment period. EPA also announces a public science meeting (via webinar) scheduled for December 5, 2019. Deadline for comments is Nov 7, 2019. [FR Notice Oct 8, 2019]


In October 2019, EPA released the draft IRIS Assessment Plan (IAP) for Inorganic Mercury Salts for public review and comment. An IRIS Assessment Plan (IAP) communicates to the public the plan for assessing each individual chemical and includes summary information on the IRIS Program’s scoping and initial problem formulation; objectives and specific aims for the assessment; the PECO (Populations, Exposures, Comparators, and Outcomes) criteria that outlines the evidence considered most pertinent to the assessment; and identification of key areas of scientific complexity. The PECO provides the framework for developing literature search strategies and inclusion/exclusion criteria, particularly with respect to evidence stream (i.e., human, animal, mechanistic), exposure and outcome measures. The IAP serves to inform the subsequent development of the chemical specific systematic review protocol.


U.S. EPA. IRIS Assessment Plan for Inorganic Mercury Salts (Scoping and Problem Formulation Materials). U.S. Environmental Protection Agency, Washington, DC, EPA/635/R-19/149, 2019.


Nagu Keshava,  Ph:  919-541-3047,  Email:

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Mercury occurs naturally in geologic materials in the environment and can exist in inorganic form as salts. In its inorganic form, mercury occurs abundantly in the environment - primarily as the minerals (e.g., cinnabar (HgS),metacinnabar) - and as impurities in other minerals. Its geologic associations are with volcanic rocks and hydrothermal systems. The abundance of each of these in the environment make it available for combining with chlorine, sulfur, and other elements as it weathers to form these and other inorganic salts. Inorganic mercury salts can be transported in water and occur in soil.

Human exposure to inorganic mercury salts can occur both in occupational and environmental settings. Occupations with higher risk of exposure to mercury and its salts include mining, electrical equipment manufacturing, and chemical and metal processing in which mercury is used. In the general population, exposure to mercuric chloride can occur through the dermal route from the use of soaps and creams or topical antiseptics and disinfectants. Exposure may also occur from consuming outdated medicinal products, such as laxatives, worming medications, and teething powders.


Date Description
Oct 2019EPA released the IRIS Assessment Plan (IAP) for Inorganic Mercury Salts for public comment and review. [Federal Register Notice Oct 8, 2019]


Following the public (webinar) meeting, the IRIS Program will use the IAP to inform the subsequent development of a chemical-specific systematic review protocol.

Additional Information

An update was made to the IAP document, see the errata sheet for details. We apologize for any inconvenience this may have caused. Thank you.

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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.

Federal Register Notices


Comments on the assessment may be submitted and reviewed using the Docket ID EPA-HQ-ORD-2019-0504

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