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EC number: 231-977-3 | CAS number: 7783-06-4
- Life Cycle description
- Uses advised against
- Endpoint summary
- Appearance / physical state / colour
- Melting point / freezing point
- Boiling point
- Density
- Particle size distribution (Granulometry)
- Vapour pressure
- Partition coefficient
- Water solubility
- Solubility in organic solvents / fat solubility
- Surface tension
- Flash point
- Auto flammability
- Flammability
- Explosiveness
- Oxidising properties
- Oxidation reduction potential
- Stability in organic solvents and identity of relevant degradation products
- Storage stability and reactivity towards container material
- Stability: thermal, sunlight, metals
- pH
- Dissociation constant
- Viscosity
- Additional physico-chemical information
- Additional physico-chemical properties of nanomaterials
- Nanomaterial agglomeration / aggregation
- Nanomaterial crystalline phase
- Nanomaterial crystallite and grain size
- Nanomaterial aspect ratio / shape
- Nanomaterial specific surface area
- Nanomaterial Zeta potential
- Nanomaterial surface chemistry
- Nanomaterial dustiness
- Nanomaterial porosity
- Nanomaterial pour density
- Nanomaterial photocatalytic activity
- Nanomaterial radical formation potential
- Nanomaterial catalytic activity
- Endpoint summary
- Stability
- Biodegradation
- Bioaccumulation
- Transport and distribution
- Environmental data
- Additional information on environmental fate and behaviour
- Ecotoxicological Summary
- Aquatic toxicity
- Endpoint summary
- Short-term toxicity to fish
- Long-term toxicity to fish
- Short-term toxicity to aquatic invertebrates
- Long-term toxicity to aquatic invertebrates
- Toxicity to aquatic algae and cyanobacteria
- Toxicity to aquatic plants other than algae
- Toxicity to microorganisms
- Endocrine disrupter testing in aquatic vertebrates – in vivo
- Toxicity to other aquatic organisms
- Sediment toxicity
- Terrestrial toxicity
- Biological effects monitoring
- Biotransformation and kinetics
- Additional ecotoxological information
- Toxicological Summary
- Toxicokinetics, metabolism and distribution
- Acute Toxicity
- Irritation / corrosion
- Sensitisation
- Repeated dose toxicity
- Genetic toxicity
- Carcinogenicity
- Toxicity to reproduction
- Specific investigations
- Exposure related observations in humans
- Toxic effects on livestock and pets
- Additional toxicological data
Endpoint summary
Administrative data
Description of key information
H2S is regarded as irritating to skin, eyes and moucous membranes (of the respiratory tract).
Key value for chemical safety assessment
Skin irritation / corrosion
Endpoint conclusion
- Endpoint conclusion:
- adverse effect observed (irritating)
Eye irritation
Endpoint conclusion
- Endpoint conclusion:
- adverse effect observed (irritating)
Respiratory irritation
Endpoint conclusion
- Endpoint conclusion:
- adverse effect observed (irritating)
Additional information
Skin irritation/ corrosion:
There is no specific study on the skin irritation/corrosion of H2S avaliable. Nevertheless it seems meaningful to evaluate the irritating potential of H2S from the existing studies with inhalative exposure. The inhalative exposure was done in chambers with whole body exposure. No effects on the skin were observed up to lethal concentrations.
However the skin irritation potential can further be evaluated on the basis of an acute dermal toxicity study with NaHS which showed irritating potential.
At 20 °C H2S dissolves in water up to 3.98 g/L. H2S can stay present in water for several hours. Nevertheless because of its considerable vapour pressure H2S will evaporate from the water into the breathing air. In aqueous environments, H2S and e.g. the corresponding salt NaHS are immediately hydrolyzed in water and, as a function of pH, an equilibrium is established between S2-, HS-, and H2S, with increasing H2S formation at decreasing pH.
As there is no acute dermal toxicity study with H2S available, the acute dermal toxicity study with 31 -32% NaHS can be taken to evaluate the acute dermal toxicity of H2S. The lethal effects emerged within 2 hours after application. After 24 hours the skin at the application site showed mild reddening and eschar. Beside this local effect in all doses all dosed animals showed symptoms of unbalancing, lowest dosage: 100 mg/kg bw (= 19.6 mg H2S/ kg). Under consideration that 10 mL/kg test solution were applied and a water solubility of 4 mg/mL a maximum possible dose of 40 mg/kg H2S within this 10 mL can be calculated. Although the exposure in the study was unrealistically long with respect to the working situation the substance H2S is classified as irritating to the skin.
Eye irritation:
There is no guideline study on the eye irritation/corrosion of H2S avaliable. Nevertheless it is possible to evaluate the irritating potential of H2S from the existing studies with inhalative exposure. Male Fischer 344 rats (number per group not stated) were exposed to 0, or 400 ppm hydrogen sulfide for 4 hours or 1500 ppm hydrogen sulfide for 4 minutes. Immediately after exposure, the eyes were washed with 0.4 ml of saline and the lavage fluid collected for exfoliative cytology. Exposure to hydrogen sulfide increased the number of exfoliated cells and the proportion of conjunctival to corneal epithelial cells recovered compared to controls. This can be seen as a consequnece of an irritation to the eye.
Respiratory irritation:
Studies with repeated (Dorman 2000) inhalative exposure revealed irritation of the mucous membranes in the nose after 6 hours exposure to concentrations of H2S in the air of 30 ppm (42 mg/m³) and higher. Based on the respiratory lesions observed in the studies with inhalation exposure by Dorman et al. (2000) H2S is calssified as H335: May cause respiratory irritation, according to the CLP-criteria/R37: Irritating to the respiratory system, according to DSD.
Although there are no specific guideline studies availiable, the existing data allow an evaluation of the irritating / corrosive potential of H2S. Further animal studies are not necessary.
Justification for selection of skin irritation / corrosion endpoint:
There is no specific study on the skin irritation/corrosion of H2S avaliable. Nevertheless it seems meaningful to evaluate the irritating potential of H2S from the existing studies with inhalative exposure. The inhalative exposure was done in chambers with whole body exposure. No effects on the skin were observed up to lethal concentrations.
However the skin irritation potential can further be evaluated on the basis of an acute dermal toxicity study with NaHS which showed irritating potential.
At 20 °C H2S dissolves in water up to 3.98 g/L. H2S can stay present in water for several hours. Nevertheless because of its considerable vapour pressure H2S will evaporate from the water into the breathing air. In aqueous environments, H2S and e.g. the corresponding salt NaHS are immediately hydrolyzed in water and, as a function of pH, an equilibrium is established between S2-, HS-, and H2S, with increasing H2S formation at decreasing pH.
As there is no acute dermal toxicity study with H2S available, the acute dermal toxicity study with 31 -32% NaHS can be taken to evaluate the acute dermal toxicity of H2S. The lethal effects emerged within 2 hours after application. After 24 hours the skin at the application site showed mild reddening and eschar. Beside this local effect in all doses all dosed animals showed symptoms of unbalancing, lowest dosage: 100 mg/kg bw (= 19.6 mg H2S/ kg). Under consideration that 10 mL/kg test solution were applied and a water solubility of 4 mg/mL a maximum possible dose of 40 mg/kg H2S within this 10 mL can be calculated. Although the exposure in the study was unrealistically long with respect to the working situation the substance H2S is classified as irritating to the skin.
Justification for selection of eye irritation endpoint:
There is no guideline study on the eye irritation/corrosion of H2S avaliable. Nevertheless it is possible to evaluate the irritating potential of H2S from the existing studies with inhalative exposure.
Male Fischer 344 rats (number per group not stated) were exposed to 0, or 400 ppm hydrogen sulfide for 4 hours or 1500 ppm hydrogen sulfide for 4 minutes. Immediately after exposure, the eyes were washed with 0.4 ml of saline and the lavage fluid collected for exfoliative cytology. Exposure to hydrogen sulfide increased the number of exfoliated cells and the proportion of conjunctival to corneal epithelial cells recovered compared to controls.
This can be seen as a consequnece of an irritation to the eye.
Effects on skin irritation/corrosion: slightly irritating
Effects on eye irritation: slightly irritating
Effects on respiratory irritation: irritating
Justification for classification or non-classification
Based on the evaluation of the available data hydrogen sulphide is regarded as irritating to skin, eyes and irritating to the moucous membranes (of the respiratory tract) after repeated exposure. The skin irritation potential is relevant for H2S in aqueous solutions only.
In accordance with Regulation (EC) No 1272/2008 H2S shall be classified as
- Category 2, skin irritant (H315: Causes skin irritation),
- Category 2 (irritating to eyes) (H319: Causes serious eye irritation),
- STOT Single Exp. 3 (H335: May cause respiratory irritation),
and as R38, R36, R37 respectively in accordance with directive 67/548/EEC.
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