Renewable hydrocarbons (diesel type fraction)

Endpoint summary

Description of key information

Testing of terrestrial toxicity does not appear scientifically necessary.

Due to high lipophilicity of NExBTL renewable diesel, sediments and soils are the target compartments for the test material when released into environment, however due to rapid biodegradation this risk may be mitigated significantly.

According to chemical safety assessment, NExBTL renewable diesel does not pose a risk to other compartments (water/sediment). It was not found to be acutely toxic to any of the aquatic species tested (algae, crustacea, fish and sediment-dwelling amphipod). In an acute toxicity test with a sediment-dwelling amphibod Corophium volutator, the LC50 of the test material was 1200 mg/kg (d.w.), which equals 3000 mg/l (calculated with density of the solids obtained from the Table R.16 -16). The NOEC was 373 mg/kg (d.w.), equivalent to 933 mg/l. Furthermore, the test material was found readily biodegradable in an OECD 301B CO₂evolution test.

Numerous studies have also shown that alkanes are readily biodegradable in soils and sediments (Hoeppel RE et al 1991, Hawle-Ambrosch et al 2007, Miethe D et al 1994, Salanitro J 2001, Sugiura et al 1996). Also, experimental results indicated that n-C10-C20-alkanes did not have adverse effects on the growth of corn Zea maysand red beans Phaseolus nipponesi (Baek et al., 2004).

The only use that may lead to soil exposure is in tarmac (SU8/PC9b/PROC23/ERC8e) and this use is infrequent. Based on these facts, the expected soil exposure will be occasional, duration of the exposure will be short and the effects to soil organisms will be low.

Since biodegradability of compounds is assumed more rapid in soils compared to anaerobic and low temperature sediments (half-lives were estimated 1000 times higher in sediments than in soils using EUSES), the exposure time and thus the risk posed by the test material to the organisms is likely to be lower in soils than in sediments.

Mammalian toxicity testing indicated that NExBTL renewable diesel has a low potential to cause adverse long-term or reproductive effects. Based on this fact, in addition to low bioavailability via food chain, NExBTL renewable diesel is not expected to cause toxic effects to birds.

 

REFERENCES:

Baek et al, 2004, Effects of crude oil components, oil components and bioremediation on plant growth, Journal of Environmental Science and Health A39(9): 2465-2472.

Hawle-Ambrosch E, Ripe W, Dornmayr-Pfaffenhuemer M, Radax C, Holzinger A and Stan-Lotter H, 2007, Biodegradation of fuel oil hydrocarbons by a mixed bacterial consortium in sandy and loamy soils, Biotechnology Journal 2(12), 1564-1568.

Hoeppel RE, Hichee RE and Arthur MF, 1991, Bioventing soils contaminated with petroleum hydrocarbons. J. Indust. Microbiol. 8, 141-146.

Miethe D, Riis V and Babel W, 1994, The relationship between the microbial activity of the autochthonous microorganisms of pristine and contaminated soils and their potential for the degradation of mineral oil hydrocarbons. Acta Biotechnol. 14,131-140.

Sugiura K, Ishihara M, Shimauchi T and Harayama S, 1997, Physicochemical properties and biodegradability of crude oil Environmental Science and Technology 31(1), 45-51.