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Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information


Photodegradation in air:

The calculated atmospheric half-life of 4-chlorotoluene is 8.8 days (Bayer Industry Services, 2004).


As chlorine is a ring substituent, hydrolysis is not expected to be an important process in determining the environmental fate of p-chlorotoluene (Jaber, 1984). Neutral pH values when dissolved in water and stability are basic properties of chlorotoluenes (Rossberg, 2000).


Biodegradation in water: screening tests

Readily biodegradation:

After 14 d, 0 % of 4 -chlorotoluene were degraded preforming a ready biodegradabiltiy test corresponding to OECD 301C (MITI, 1992).

Inherently biodegradation:

4 -Chlorotoluene was degraded about 86 % after 28 d testing the inherent biodegradability of the test substance. Due to the significant elimination (68 %) within 3 h there is evidence that the disappearance of p-chlorotoluene is caused by physico-chemical effects rather than biodegradation processes.


Bioaccumulation: aquatic/sediment

The bioconcentration factor for 4-chlorotoluene was determined at two different concentration levels using fish (MITI, 1992):

0.3 mg/L: BCF 21.9 - 76.5

0.03 mg/L: BCF 14 - 101.6

Transport and Distribution

Adsorption/desorption behaviour

The distribution behaviour of 4 -chlorotoluene between water and soil was determined according to OECD guideline 106 (batch method). Three different soils were used yielding the following results (RCC, 1992):

sand: Koc = 512.2

loamy sand: Koc = 327.1

sandy loam: Koc = 335.9

Henry's Law Constant

The Henrys Law Constant for 4 -chlorotoluene was calculated based on the Bond Method (446.8 Pa*m³/mole) as well as the Group Method (494.5 Pa*m³/mole) applying the EPI-Suite software (Bayer Industry Services, 2004).

Distribution Modelling

The distribution of p-chlorotoluene in a "unit world" was calculated according to the Mackay fugacity model level I (Bayer Industry Services, 2004) based on the physico-chemical properties of the test substance. The main target compartment for p-chlorotoluene is air with 99.67 %, followed by water with 0.24 %, and soil with 0.04%.