o-TOLUIDINE CAS N°: 95-53-4 - UNEP Chemicals

OECD SIDS o-TOLUIDINE
3. ENVIRONMENTAL FATE AND PATHWAYS ID: 95-53-4
DATE: 07.01.2005
Inoculum : other: sludge sampling from different sewage plants, natural waterbodies
and soil
Concentration : 100 mg/l related to Test substance
related to
Contact time :
Degradation : = 65.4 (±) % after 28 day(s)
Result : readily biodegradable
Deg. product :
Method : other: Japanese Guideline by MITI (1974). Comparable to OECD TG 301
C, Modified MITI Test I
Year : 1992
GLP : no
Test substance : other TS: o-Toluidine, purity is not specified
Method : The test was conducted in accordance with 'Biodegradation test of
chemical substance by microorganisms etc.' stipulated in the Order
Prescribing the Items of the Test Relating to the New Chemical Substance
(1974, Order of the Prime Minister, the Minister of Health and Welfare, the
Minister of International Trade and Industry No.1). This guideline
corresponds to '301C, Ready Biodegradability: Modified MITI Test I'
stipulated in the OECD Guidelines for Testing of Chemicals (1981)
Remark : No information on the 10 d window criteria is given
Test condition : Sludge samples were collected from the 10 sites such as sewage
treatment works, industrial wastewater treatment works, rivers, lakes and
sea throughout Japan and mixed thoroughly. A filtrate (500 ml) of the
supernatant of the mixed sludge was then mixed with 5 l of the filtered
supernatant of an activated sludge in the present use. After the combined
sludge solution (pH adjusted at 7.0+/-1.0) was aerated for 30 min, the
supernatant corresponding to 1/3 of the whole volume was discarded. An
equal volume of pure water was then added to the remaining portion and
the supernatant (final concentration of 0.1 %) of the resulting sludge
solution was mixed with sterile mineral medium and continuously aerated
at 25+/-2 °C to allow minimization of residual dissolved organic carbon
according to the procedure outlined in the TG.
The test was conducted in triplicate with o-toluidine in sterile mineral
medium at 100 mg/l and with a small volume of the activated sludge to give
a final concentration of 30 mg/l in 300 ml.
A blank control (sterile mineral medium only), positive control (aniline as
reference compound at 100 mg/l) and o-toluidine control (o-toluidine in
pure water at 100 mg/l) in 300 ml were incubated simultaneously.
Oxygen comsumption resulting from biodegradation of the compounds was
measured over 28-day test period using an Okura Electric Closed System
Oxygen Consumption measuring apparatus (Coulometer). Percentage
biodegradation was calculated based on BOD, TOC and HPLC analysis.
The test solutions were maintained in a dark room at a temperature of
25+/-1 °C and continuously stirred by magnetic stir bars over the 28-day
test period.
Degradation (%) was obtained from the following equations:
BOD:
Degradation (%) = (BOD-B)/ThOD x 100
BOD (mg): BOD in (sludge + o-toluidine system)
B (mg): BOD in sludge blank
ThOD: theoretical oxygen demand required when o-toluidine
was completely oxidized.
HPLC:
Degradation (%) = (Sw-Ss)/Sw x 100
Sw (mg): Residual amount of o-toluidine detected by HPLC in (water + otoluidine
system)
Ss (mg): Residual amount of o-toluidine detected by HPLC in (sludge + o-
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