Single Wall Carbon Nanotubes (SWCNT)

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because the substance is highly insoluble in water, hence indicating that aquatic toxicity is unlikely to occur

the study does not need to be conducted because the substance is unlikely to cross biological membranes, hence indicating that aquatic toxicity is unlikely to occur

Description of key information

The substance is entirely insoluble in water as shown in pre-studies performed in preparation of in vitro mutagenicity studies (see Additional physico-chemical information DispersionInBSA_Talmon_2019 and Additional physico-chemical information DispersionInBSA_Swansea_2019 and corresponding endpoint summary Additional physico-chemical information DispersionInBSA). Thus, dissolution of the substance in water is not of concern and bioavailability to fish is unlikely. Furthermore, the substance is, due to its size, not capable of passing biological cell membranes. As implied by test data with E. coli bacteria (see K_Toxicity to microorganisms 2009 as published by E. A. Obraztsova et al., 2008) following a prolonged period the substance may damage cell membranes leading to cyctotoxicity and similar effects are known from medical applications, published in scientific literature, reporting about inflammation in tissue, but such effects are long term effects that would require long-term toxicity data. So far, aquatic toxicity data with loading rates of 100 mg/L in daphnia and algae do not indicate any toxicity to aquatic organisms and thus acute fish toxicity data are not considered scientifically justifiable. At a higher tonnage band (>100 T/a), long-term fish toxicity studies may be considered instead.