Header

UZH-Logo

Maintenance Infos

Criteria for designation with an “H” [MAK Value Documentation, 2014]


Hartwig, A; MAK Commission; et al; Arand, Michael (2017). Criteria for designation with an “H” [MAK Value Documentation, 2014]. The MAK Collection for Occupational Health and Safety, 2(3):1112-1118.

Abstract

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has evaluated criteria to designate substances with an “H” which can be absorbed via the skin in such amounts as to contribute significantly to systemic toxicity. Information on the uptake via the skin can be obtained from studies in humans, animals and from in vitro models preferably with human skin. Ideally, these data allow the calculation of a flux, i.e. the amount absorbed per cm2 skin and hour. If these experimental studies are lacking, fluxes based on physicochemical data are calculated with three mathematical models for an aqueous saturated solution or a read‐across to similar substances with a better database is used. For gaseous substances, the water solubility of the substance is calculated at a substance concentration in the gas phase that corresponds to the MAK value and the flux is modelled.
An exposure time of one hour and an exposed skin area of 2000 cm2 which corresponds to the area of both hands and forearms is used as a practical exposure model for liquids. For gases, the exposure time is taken as 8 hours and the exposed skin area as 1.8 m2.
With the obtained fluxes, the body burden is calculated and if it exceeds 25% of the chronic systemic NOAEL for workers, the substance is designated with an “H”. If the substance is genotoxic and no systemic NOAEL could be deduced, a qualitative proof of uptake is enough for the designation with an “H”.

Abstract

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has evaluated criteria to designate substances with an “H” which can be absorbed via the skin in such amounts as to contribute significantly to systemic toxicity. Information on the uptake via the skin can be obtained from studies in humans, animals and from in vitro models preferably with human skin. Ideally, these data allow the calculation of a flux, i.e. the amount absorbed per cm2 skin and hour. If these experimental studies are lacking, fluxes based on physicochemical data are calculated with three mathematical models for an aqueous saturated solution or a read‐across to similar substances with a better database is used. For gaseous substances, the water solubility of the substance is calculated at a substance concentration in the gas phase that corresponds to the MAK value and the flux is modelled.
An exposure time of one hour and an exposed skin area of 2000 cm2 which corresponds to the area of both hands and forearms is used as a practical exposure model for liquids. For gases, the exposure time is taken as 8 hours and the exposed skin area as 1.8 m2.
With the obtained fluxes, the body burden is calculated and if it exceeds 25% of the chronic systemic NOAEL for workers, the substance is designated with an “H”. If the substance is genotoxic and no systemic NOAEL could be deduced, a qualitative proof of uptake is enough for the designation with an “H”.

Statistics

Citations

Dimensions.ai Metrics

Altmetrics

Additional indexing

Item Type:Journal Article, not_refereed, original work
Communities & Collections:04 Faculty of Medicine > Institute of Pharmacology and Toxicology
07 Faculty of Science > Institute of Pharmacology and Toxicology
Dewey Decimal Classification:570 Life sciences; biology
610 Medicine & health
Language:English
Date:26 July 2017
Deposited On:17 Oct 2019 12:15
Last Modified:17 Oct 2019 12:15
Publisher:Wiley-VCH Verlag
ISSN:2509-2383
ISBN:9783527600410
OA Status:Closed
Publisher DOI:https://doi.org/10.1002/3527600418.mb0hmrkkrie5617

Download

Full text not available from this repository.
View at publisher

Get full-text in a library