Subject: SIDS INITIAL ASSESSMENT PROFILE for Acetone cyanohydrin
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Date: Fri, 2 Apr 2010 12:24:20 +0200

OECD SIDS                                                        ACETONE CYANOHYDRIN

FOREWORD                                             INTRODUCTION

ACETONE CYANOHYDRIN

CAS N°75-86-5

SIDS INITIAL ASSESSMENT PROFILE

CAS-NO

75-86-5

CHEMICAL NAME

Acetone cyanohydrin

STRUCTURAL FORMULA

(CH3)2C(OH)CN

RECOMMENDATION OF THE SPONSOR COUNTRY

[ X ] presently of low priority for further work

[  ] requiring further information to assess identified concerns

[  ] candidate for in-depth risk assessment with a view to possible risk reduction activities

SHORT SUMMARY OF THE REASONS WHICH SUPPORT THE RECOMMENDATION

Environment -The toxicity of acetone cyanohydrin is believed to be predominantly attributable to dissociation of the cyanide molecule with the resultant formation of molecular (undissociated) hydrocyanic acid. Hydrocyanic acid, by virtue of its small size and lack of charge, readily penetrates the external membranes of aquatic organisms (Doudoroff, 1976) and inhibits respiration. Any potential environmental problems would be caused by cyanide rather than the parent compound.

There are no data on the environmental concentrations of acetone cyanohydrin and there is no basis to model environmental concentrations from release since the compound is an intermediate which rapidly dissociates, and is manufactured and used in enclosed systems. Therefore, it is difficult to interpret the PNEC. However, the rapid dissociation and tight controls on the release of acetone cyanohydrin mean that it is unlikely that the PNEC will be attained.

Therefore, it would appear that acetone cyanohydrin represents little risk to the environment under current production and use. No further work is recommended.

Human Health - The rapid formation of hydrogen cyanide from acetone cyanohydrin is of concern, and the critical adverse health effect is acute lethality. However, at anticipated levels of human exposure no systemic effects are likely to occur. The chemical is not genotoxic or toxic to development or the reproductive system.

No further toxicity tests are required. Depending on workplace exposure assessments at individual sites protective measures may need to be increased.

IF FURTHER WORK IS RECOMMENDED, SUMMARISE ITS NATURE

No further work is required

FULL SIDS SUMMARY

CAS No: 75-86-5 | SPECIES | PROTOCOL | RESULTS
PHYSICAL-CHEMICAL | | |
2.1 Melting Point | | not known | -19°C
2.2 Boiling Point | | extrapolated | 164-185°C (at 101 kPa)
2.3 Density | | | -
2.4 Vapour Pressure | | no method; will vary depending on purity | 0.1 kPa at 20°C
2.5 Partition Coefficient (Log Pow) | | calculated | -1.0 & -0.54
2.6a. Water Solubility | | no method | miscible in all proportions
2.6b. pH | | | not known (approx. pH 2)
pKa | | | not known
2.12 Oxidation: Reduction Potential | | | -
ENVIRONMENTAL FATE/DEGRADATION | | |
3.1.1 Photodegradation | | | In air T½ = 1440 hours (60 days)
3.1.2 Stability in water | | at pH 4.9, 6.3 & 6.8 | T½ = 57, 28 & 8 minutes
3.2 Monitoring data | | | no data
3.3 Transport and Distribution | | | no data
3.5 Biodegradation | activated sludge | data for hydrogen cyanide | complete degradation at < 60 mg/l
ECOTOXICOLOGY | | |
4.1 Acute/Prolonged Toxicity to Fish | rainbow trout (Oncorhynchus mykiss) | nominal concentration; static test; EPA methodology | LC50 (96 hr) = 0.22 mg/l
4.2 Acute Toxicity to Aquatic Invertebrates: Daphnia | Daphnia magna | nominal concentration; static test; EPA methodology | EC50 (48 hr) = 0.13 mg/l
4.3 Toxicity to Aquatic Plants eg. Algae | Alga (Ankistrodesmus falcatus) | potassium cyanide; based on growth; pH 8-10; temperature 20°C | EC50 = 1.25 mg/l
4.5.2 Chronic Toxicity to Aquatic Invertebrates (Daphnia) | | | -
4.6.1 Toxicity to Soil Dwelling Organisms | | | -
4.6.2 Toxicity to Terrestrial Plants | | | -
4.6.3 Toxicity to Other Non Mammalian Terrestrial Species (Including Birds) | | | -