1,5,2,4-dioxadithiane 2,2,4,4-tetraoxide

Endpoint summary

Additional information

1,5,2,4-dioxadithiane 2,2,4,4-tetraoxide (MMDS) is rapidly hydrolised into methandisulphonic acid (MDSA) and formaldehyde in water. Within 104 minutes, all MMDS hydrolized into MDSA and formaldehyde. As a result of this, it is very difficult to prepare the test solution of MMDS. Therefore, according to the OECD guidance document, No.23, September 2000, "Guidance Document of Aquatic Toxicity testing of Difficult Substances and Mixtures", the toxicity studies in algae, Daphnia magna and fish were conducted with MDSA.

Short-Term Toxicity to fish

This study was conducted according to OECD 203 Guideline.

The 96-hour LC50 without pH adjustment was 67 mg/L. The LC50 with pH adjustment was >100 mg/L. Therefore, it was considered that the effect to the test organisms was caused by low pH.

Short-Term Toxicity to Aquatic Invertebrates

This study was conducted according to OECD 202 Guideline.

The 48 -hour EC50 without pH adjustment was 45 mg/L. The EC50 with pH adjustment was >100 mg/L. Therefore, it was considered that the effect to the test organisms was caused by low pH.

Toxicity to Aquatic Algae and Cyanobacteria

The study was performed in accordance with OECD 201Guideline. The EC50 and NOEC of the test substance without pH adjustment were 42 mg/L and 31 mg/L, respectively. In contrast, the EC50 and NOEC of the test substance in a pH adjusted test were >100mg/L and =100 mg/L, respectively. Therefore, it was considered that the effect of test organism was owing to the pH of test solution.

Toxicity to microorganisms

An activated sludge respiration inhibition test was performed according to OECD 209. The test showed that MMDS was not toxic to waste water (activated sludge) bacteria, without or with pH adjustment to 7.5 ± 0.5, at or below a loading rate of 100 mg/l (NOEC).