Trisodium 8-hydroxypyrene-1,3,6-trisulphonate

PBT assessment

PBT assessment: overall result

Reference

Name:

trisodium 8-hydroxypyrene-1,3,6-trisulphonate

Type of composition:

boundary composition of the substance

State / form:

solid: particulate/powder

Reference substance:

trisodium 8-hydroxypyrene-1,3,6-trisulphonate

PBT status:

the substance is not PBT / vPvB

Likely routes of exposure:

Classification of Trisodium 8 -hydroxypyrene-1,3,6-trisulphonate for effects in the environment:

 

The chemical Trisodium 8-hydroxypyrene-1,3,6-trisulphonate (CAS no. 6358-69-6) is used as a pH indicator for biological systems and as a colorant. It is also used as a dye in cosmetics and pharmaceutical products. The aim was to assess whether the PBT criterion within Annex XIII was fulfilled for Trisodium 8-hydroxypyrene-1,3,6-trisulphonate. The PBT criterion was herein assessed based on experimental data in conjunction with standardized environmental fate models. Here follows a description of the PBT assessment.

 

Persistence assessment

The tested substance does not fulfil the P criterion within Annex XIII based on the assessment that here follows:

 

Biotic degradation

28-days Closed Bottle test following the OECD guideline 301 D to determine the ready biodegradability of the test item (Experimental study report, 2017). The study was performed at a temperature of 20°C. The test system included control, test item and reference item. Domestic waste water, surface soil and soil samples from polluted sites receiving predominantly domestic waste was collected and were mixed to get diluted suspension. The inoculum was kept aerobic until being used for experiment by supplying organic and inorganic sources required by micro flora to sustain at controlled laboratory conditions. This gave the bacterial count as 107 to 108 CFU/ml. At the regular interval microbial plating was also performed on agar to confirm the vitality and CFU count of microorganism. The concentration of test and reference item (Sodium Benzoate) chosen for both the study was 4 mg/L, while that of inoculum was 32 ml/l. OECD mineral medium was used for the study. ThOD (Theoretical oxygen demand) of test and reference item was determined by calculation. % degradation was calculated using the values of BOD and ThOD for test item and reference item. The % degradation of procedure control (reference item) was also calculated using the values of BOD & ThOD and was determined to be 63.85% at 20 ± 1°C. Degradation of Sodium Benzoate exceeds 78.91% on 7 days & 61.44% on 14th day. As the fluctuation of degradation due to D.O depletion in the blank. The activity of the inoculum was thus verified and the test can be considered as valid. The BOD28 value of test chemical was observed to be 0.44 mgO2/mg. ThOD was calculated as 1.14 mgO2/mg. Accordingly, the % degradation of the test item after 28 days of incubation at 20 ± 1°C according to Closed Bottle test was determined to be 38.59%. Based on the results, the test item, under the test conditions, was considered to be primary inherently biodegradable in nature.

 

Thus, based on the available information, it indicates that chemical Trisodium 8-hydroxypyrene-1,3,6-trisulphonate can be considered to be primary inherently biodegradable in water and thus likely to be not persistent (not P) in nature.

 

Bioaccumulation assessment

The tested substance does not fulfil the B criterion within Annex XIII based on the assessment that here follows:

 

Theoctanol water partition coefficient of the test chemical was determined to be ranges from -3.97 to -0.68, respectively, which is less than the threshold of 4.5. If this chemical is released into the aquatic environment, there should be a low risk for the chemical to bioaccumulate in fish and food chains.

 

Toxicity assessment

The tested substance does not fulfil the T criterion within Annex XIII based on the assessment that here follows:

 

Mammals

The tested chemical is regarded to be not classified for carcinogenicity, mutagenicity and reprotoxicity, Further, there is no evidence of chronic toxicity, as identified by the classifications STOT (repeated exposure), category 1(oral, dermal, inhalation of gases/vapours, inhalation of dust/mist/fume) or category 2 (oral, dermal, inhalation of gases/vapours, inhalation of dust/mist/fume).

 

Aquatic organisms

All of the available short-term eco-toxicity estimations for fish, invertebrates and algae for the substanceTrisodium 8-hydroxypyrene-1,3,6-trisulphonateindicates the LC50/EC50 value to be in the range>100 – 2703 mg/L and on the basis of short term ecotoxicity data for aq. algae, the EC50 value was determined to be ranges from 20 to>100 mg/l. The value (i.e, 20 mg/l) suggest that the substance is likely to be hazardous to aquatic algae. But based on the EC50 value (i.e,>100 mg/l) for aq. algae from experimental study report (K1 study) and performed as per the OECD test guideline, test chemical can be considered as non-toxic to aq. algae. These values suggest that the substance is likely to be not hazardous to aquatic organisms at environmentally relevant concentrations and can be considered to be ‘Not classified’ as per the CLP regulation.

 

There are no available long-term toxicity evaluations for Trisodium 8-hydroxypyrene-1,3,6-trisulphonate. By speculation, long-term NOEC for aquatic organisms were not expected for the substance at concentration below 0.01 mg/L based on the data mentioned above

 

The chemical was therefore not considered as hazardous to aquatic environments as per the criteria set out in Annex XIII.

 

Conclusion

Based on critical, independent and collective evaluation of information summarized herein, the tested compound does not fulfil the P, B and T criterion and has therefore not been classified as a PBT compound within Annex XIII.