Chemical Name：S-(2,3-Dihydro-5-methoxy-2-oxo-1,3,4-thiadiazol-3-yl)methyl O,O-dimethyl phosphorodithioate; Methidathion; DMTP
CAS：950-37-8

Hazard class		Classification	Symbol	Signal word	Hazard statement	Precautionary statement	Rationale for the classification
1	Acute toxicity （Oral）	Category 2		Danger	H300: Fatal if swallowed	P301+P310: IF SWALLOWED: Immediately call a POISON CENTER or doctor/physician. P264: Wash ... thoroughly after handling. P270: Do not eat, drink or smoke when using this product. P321: Specific treatment （see ... on this label）. P330: Rinse mouth. P405: Store locked up. P501: Dispose of contents/container to ...	Based on the LD50 values of 40mg/kg and 48mg/kg reported in the two oral studies with rats (Agricultural Chemical Registration Data (1987)).
1	Acute toxicity （Dermal）	Not classified	-	-	-	-	Based on the absence of mortality at the highest dose of 4,000mg/kg observed in the dermal studies with rats (Agricultural Chemical Registration Data (1987)).
1	Acute toxicity （Inhalation: Gases）	Not applicable	-	-	-	-	Due to the fact that the substance is a solid according to the GHS definition and inhalation of its gas is not expected.
1	Acute toxicity （Inhalation: Vapours）	Classification not possible	-	-	-	-	No data available
1	Acute toxicity （Inhalation: Dusts and mists）	Category 2		Danger	H330: Fatal if inhaled	P304+P340: IF INHALED: Remove victim to fresh air and keep at rest in a position comfortable for breathing. P403+P233: Store in a well-ventilated place. Keep container tightly closed. P260: Do not breathe dust/fume/gas/mist/vapours/spray. P271: Use only outdoors or in a well-ventilated area. P284: Wear respiratory protection. P310: Immediately call a POISON CENTER or doctor/physician. P320: Specific treatment is urgent （see ... on this label）. P405: Store locked up. P501: Dispose of contents/container to ...	Based on the rat LC50 (inhalation exposure) value of 0.109mg/L representing the lower of the two testing data, 0.109mg/L and 0.173mg/L (Agricultural Chemical Registration Data, 1993).
2	Skin corrosion/irritation	Not classified	-	-	-	-	Based on the evidence of only mild irritation (mean Draize score of 1.2), with effects fully clearing after 72 hours, observed in rabbit skin irritation studies (Agricultural Chemical Registration Data (1987)), that suggests little potential for skin irritation.
3	Serious eye damage/eye irritation	Category 2A		Warning	H319: Causes serious eye irritation	P305+P351+P338: IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing. P337+P313: If eye irritation persists: Get medical advice/attention. P264: Wash ... thoroughly after handling. P280: Wear protective gloves/protective clothing/eye protection/face protection.	Based on the description in the report on rabbit eye irritation tests (Agricultural Chemical Registration Data (1987)): "The affected animals exhibited a Draize score of 3 or greater and were not fully recovered on day 7."
4	Respiratory sensitization	Classification not possible	-	-	-	-	No data available
4	Skin sensitization	Not classified	-	-	-	-	Based on no evidence of sensitization in guinea pig sensitization studies (Agricultural Chemical Registration Data (1987)).
5	Germ cell mutagenicity	Not classified	-	-	-	-	Based on negative data on in vitro reverse mutation tests (Agricultural Chemical Registration Data (1987)), in vitro chromosome aberration tests (Agricultural Chemical Registration Data (1990)) and in vivo micronucleus tests (Agricultural Chemical Registration Data (1987)).
6	Carcinogenicity	Not classified	-	-	-	-	There was no treatment-related evidence of tumor incidence observed in carcinogenicity studies in rats and mice, reported in Agricultural Chemical Registration Data (1987). Also due to the fact that the substance is classified as Category C by EPA (1993).
7	Reproductive toxicity	Category 2		Warning	H361: Suspected of damaging fertility or the unborn child	P308+P313: IF exposed or concerned: Get medical advice/attention. P201: Obtain special instructions before use. P202: Do not handle until all safety precautions have been read and understood. P281: Use personal protective equipment as required. P405: Store locked up. P501: Dispose of contents/container to ...	Based on the evidence of reduced mating frequency and reduced pup viability at doses producing adverse effects on parental animals observed in rat 2-generation reproduction studies (Agricultural Chemical Registration Data (1987)).
8	Specific target organ toxicity - Single exposure	Category 1 (nervous system)		Danger	H370: Causes damage to organs (nervous system)	P307+P311: IF exposed: Call a POISON CENTER or doctor/physician. P260: Do not breathe dust/fume/gas/mist/vapours/spray. P264: Wash ... thoroughly after handling. P270: Do not eat, drink or smoke when using this product. P321: Specific treatment （see ... on this label）. P405: Store locked up. P501: Dispose of contents/container to ...	Based on the evidence from animal studies: in rat acute oral studies, clinical signs and symptoms including reduced motor activity, generalized convulsions, salivation and tremors were found. In mouse acute oral studies, symptoms including reduced motor activity, generalized convulsions, salivation, staggering and vomiting were noted (Agricultural Chemical Registration Data (1987)). These effects were observed at dosing levels within the guidance value ranges for Category 1.
9	Specific target organ toxicity - Repeated exposure	Category 1 (liver)		Danger	H372: Cause damage to organs through prolonged or repeated exposure (liver)	P260: Do not breathe dust/fume/gas/mist/vapours/spray. P264: Wash ... thoroughly after handling. P270: Do not eat, drink or smoke when using this product. P314: Get medical advice/attention if you feel unwell. P501: Dispose of contents/container to ...	Based on the evidence from animal studies including increased liver enzyme activity and intrahepatic cholestasis (Agricultural Chemical Registration Data (1992)). These effects were observed at dosing levels within the guidance value ranges for Category 1.
10	Aspiration hazard	Classification not possible	-	-	-	-	No data available

Hazard class		Classification	Symbol	Signal word	Hazard statement	Precautionary statement	Rationale for the classification
11	Hazardous to the aquatic environment （Acute）	Category 1		Warning	H400: Very toxic to aquatic life	P273: Avoid release to the environment. P391: Collect spillage. P501: Dispose of contents/container to ...	It was classified into Category 1 from 48 hours EC50=1.1microg/L of the crustacea (Daphnia magna) (Agricultural Chemical Registration Data, 2004).
11	Hazardous to the aquatic environment （Long-term）	Category 1		Warning	H410: Very toxic to aquatic life with long lasting effects	P273: Avoid release to the environment. P391: Collect spillage. P501: Dispose of contents/container to ...	Although acute toxicity is Category 1 and bio-accumulation is low (log Kow=2.2(PHYSPROP Database, 2005)), since there was no rapidly degrading (BIOWIN), it was classified into Category 1.