X hits on this document

PDF document

DL-LACTONE CAS N°:79-50-5 - page 49 / 113

304 views

0 shares

0 downloads

0 comments

49 / 113

OECD SIDS 3. ENVIRONMENTAL FATE AND PATHWAYS

DL-LACTONE

ID: 79-50-5 DATE: 18.01.2006

Result:

Test substance: Conclusion:

standardise lab form. 5 analysed) 2 Erlenmeyer were contin lab (genera indicated i elimination expressed a time 0. Degradation test at 533 sludge star 98% elimina was termina dl-Lactone dl-Lactone concentrati a low n-oct elimination adsorption

d to 2000 mg sludge (dry mass)/l as stated on the 33 mg/l dl-lactone was added, resulting in (an 95 mg DOC/l. 2-l batches were set up in large flasks and stood on a magnetic stirrer. The vessels uously aerated and kept at room temperature in the lly not in the dark). Samples were taken at ntervals, filtered and DOC-analysed. Percentage of

(biodegradation combined with adsorption) was s residual DOC at time t divided by initial DOC at

of pure dl-lactone in an inherent Zahn-Wellens mg/l test substance and 2000 mg/l mixed activated ted rapidly, followed a sigmoid curve and attained tion as measured by DOC at 14 days, when the test ted. from Roche, "pure", not otherwise characterised. is rapidly inherently biodegradable even at higher ons. As dl-lactone is highly water-soluble and has anol/water partition coefficient, the observed

is attributed wholly to biodegradation and not to to sludge. Therefore, a high rate of biodegradation

is also predicted for dl-lactone in sewage

works.

Reliability:

(2)

valid with restrictions

Biodegradability

and

inhibition

assessment

from the

in-house

Flag: 10-MAR-2005

wastewater lab, not GLP professional laboratory Critical study for SIDS

but highly standardised test in with many years of experience. endpoint

a

(24)

(25)

Type: Inoculum:

Concentration:

Contact time: Degradation: Result: Deg. product:

aerobic other: activated sludge, mixed domestic and industrial, non-adapted 100 mg/l related to Test substance 1000 mg/l related to Test substance 21 day(s) >= 80 % after 21 day(s) inherently biodegradable not measured

Method:

Year: GLP: Test substance:

other: comparable to OECD Guide-line 302 C 1983 no as prescribed by 1.1 - 1.4

Method:

A standard inherent degradation test was performed with pure dl-lactone from lab production in a Sapromat respirometer in a test setup corresponding to OECD 302C, except that the sludge used as an inoculum was a 1:1 (dry weight) mixture of non-adapted activated sludge from one single small municipal sewage works and of activated sludge from the Roche in-house pilot sewage plant, which receives a flow-proprtional sample of the industrial wastewater. Test concentrations were 100 and 1000 mg dl-lactone/l. Activated sludge concentration is not

explicitly stated but was 200 comparable tests. Degradation consumption in test substance consumption of a blank sludge

mg (dry weight)/l in other was followed by oxygen vessels minus the oxygen vessel, compared to the COD for

Result:

dl-lactone and calculated as percent degradation. Results of this particular test are only available as a paper copy of the oxygen demand recording with handwritten final

UNEP PUBLICATIONS

49

Document info
Document views304
Page views320
Page last viewedTue Dec 06 14:02:11 UTC 2016
Pages113
Paragraphs4931
Words40344

Comments