Registration Dossier

Administrative data

Workers - Hazard via inhalation route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
0.141 mg/m³
Most sensitive endpoint:
repeated dose toxicity
Route of original study:
Oral
DNEL related information
DNEL derivation method:
ECHA REACH Guidance
Overall assessment factor (AF):
12.5
Dose descriptor starting point:
NOAEL
Value:
1 mg/kg bw/day
Modified dose descriptor starting point:
NOAEC
Value:
1.8 mg/m³
Explanation for the modification of the dose descriptor starting point:

The starting point was corrected according to Figure R.8-3 in chapter R.8 in the ECHA guidance document (version 2.1, November 2012). NOAEL(oral, rat) = 1 mg/kg bw/day => NOAEC(corrected, inhalation) = NOAEL(oral, rat) x 1/(0.38 m3/kg bw/day) x 6.7 m3/10 m3 x 0.5 = 1.8 mg/m3

AF for dose response relationship:
1
Justification:
Default value (ECHA)
AF for differences in duration of exposure:
1
Justification:
Default value (ECHA)
AF for interspecies differences (allometric scaling):
1
Justification:
Default value (ECHA)
AF for other interspecies differences:
2.5
Justification:
Default value (ECHA)
AF for intraspecies differences:
5
Justification:
Default value (ECHA)
AF for the quality of the whole database:
1
Justification:
Default value (ECHA)
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information

Local effects

Long term exposure
Hazard assessment conclusion:
no hazard identified
Most sensitive endpoint:
skin irritation/corrosion
DNEL related information
DNEL derivation method:
ECHA REACH Guidance
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
Most sensitive endpoint:
skin irritation/corrosion
DNEL related information

Workers - Hazard via dermal route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
0.2 mg/kg bw/day
Most sensitive endpoint:
repeated dose toxicity
Route of original study:
Oral
DNEL related information
DNEL derivation method:
ECHA REACH Guidance
Overall assessment factor (AF):
50
Dose descriptor starting point:
NOAEL
Value:
1 mg/kg bw/day
Modified dose descriptor starting point:
NOAEL
Value:
10 mg/kg bw/day
Explanation for the modification of the dose descriptor starting point:

In an acute dermal toxicity study with New Zealand White rabbits the LD50 was determined to be 3388 mg/kg Trimethyl Phosphate. Due to the low dermal toxicity, it appears that Trimethyl Phosphate is absorbed more rapidly through the gastrointestinal tract than the skin. According to QSAR DERMWIN the calculated dermal absorption is 10 %. Therefore, the starting point was corrected according to the slower absorption through skin.

AF for dose response relationship:
1
Justification:
Default value (ECHA)
AF for differences in duration of exposure:
1
Justification:
Default value (ECHA)
AF for interspecies differences (allometric scaling):
4
Justification:
Default value (ECHA)
AF for other interspecies differences:
2.5
Justification:
Default value (ECHA)
AF for intraspecies differences:
5
Justification:
Default value (ECHA)
AF for the quality of the whole database:
1
Justification:
Default value (ECHA)
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
Most sensitive endpoint:
skin irritation/corrosion
DNEL related information

Local effects

Long term exposure
Hazard assessment conclusion:
low hazard (no threshold derived)
Most sensitive endpoint:
skin irritation/corrosion
Acute/short term exposure
Hazard assessment conclusion:
low hazard (no threshold derived)
Most sensitive endpoint:
skin irritation/corrosion

Workers - Hazard for the eyes

Local effects

Hazard assessment conclusion:
low hazard (no threshold derived)

Additional information - workers

As trimethyl phosphate is manufactured in a closed system, exposure during synthesis may be excluded. Since this chemical is used as a polymerization catalyst, the possibility of workplace exposure through dermal route is possible when the product is filled into barrels. Dermal uptake at work place is considered to be the main exposure route while inhalation plays a minor role. However workers wear personal protective equipment (e.g. chemical cartridge respirator with an organic vapour cartridge, safety glasses and protective suits) during the filling process. Therefore, the exposure at work place is considered to be very low.

General Population - Hazard via inhalation route

Systemic effects

Long term exposure
Hazard assessment conclusion:
no hazard identified
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information

Local effects

Long term exposure
Hazard assessment conclusion:
no hazard identified
Most sensitive endpoint:
skin irritation/corrosion
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
Most sensitive endpoint:
skin irritation/corrosion
DNEL related information

General Population - Hazard via dermal route

Systemic effects

Long term exposure
Hazard assessment conclusion:
no hazard identified
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information

Local effects

Long term exposure
Hazard assessment conclusion:
no hazard identified
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified

General Population - Hazard via oral route

Systemic effects

Long term exposure
Hazard assessment conclusion:
DNEL (Derived No Effect Level)
Value:
25 µg/kg bw/day
Most sensitive endpoint:
repeated dose toxicity
Route of original study:
Oral
DNEL related information
DNEL derivation method:
ECHA REACH Guidance
Overall assessment factor (AF):
40
Dose descriptor starting point:
NOAEL
Value:
1 mg/kg bw/day
Modified dose descriptor starting point:
NOAEL
Value:
1 mg/kg bw/day
Explanation for the modification of the dose descriptor starting point:

Bioavailability in humans versus rat concerning oral route: no data are available for humans (rat: nearly complete absorption) but the same bioavailability is assumed, no correction.

Same route of exposure, no correction.

AF for dose response relationship:
1
Justification:
Default (DNEL calculator)
AF for differences in duration of exposure:
1
Justification:
Default (DNEL calculator)
AF for interspecies differences (allometric scaling):
4
Justification:
Default (DNEL calculator)
AF for other interspecies differences:
1
Justification:
Default (DNEL calculator)
AF for intraspecies differences:
10
Justification:
Default (DNEL calculator)
AF for the quality of the whole database:
1
Justification:
Default (DNEL calculator)
AF for remaining uncertainties:
1
Acute/short term exposure
Hazard assessment conclusion:
no hazard identified
DNEL related information

General Population - Hazard for the eyes

Local effects

Hazard assessment conclusion:
no hazard identified

Additional information - General Population

The highest exposure to the general population via the environment would be expected through drinking water processed from surface water. Based on the physical chemical properties of trimethyl phosphate, a significant removal of during processing is not expected. Although PECglobal cannot be estimated, the concentration in drinking water is assumed to be less than 1.5 x 10-4 mg/l. Assuming a consumption of drinking water of 2 L/day and an average body weight of 60 kg, a daily intake of 5.0 x 10-6 mg/kg/day can be estimated. The margin of safety is very large.

The exposure through food is estimated to be negligible as the substance has a low bioaccumulation potential.

Therefore, health risk through the environment, in general, is considered to be low due to its use pattern and exposure situation.