NALCO 73280

Basic toxicokinetics

Administrative data

Endpoint:

basic toxicokinetics

Type of information:

other: Toxicokinetic Assessment

Adequacy of study:

key study

Study period:

Not Reported

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: This toxicokinetics assessment was conducted by a capable person in a GLP facility.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2003

Report date:

2003

Materials and methods

Objective of study:

toxicokinetics

Principles of method if other than guideline:

This desk-based study used existing physico-chemical, environmental fate and toxicological data to assess the toxicokinetics of the test item.

GLP compliance:

yes

Test material

Test material information

Constituent 1

Details on test material:

Idenitification of test item (as cited in study report): NALCO 01WC026/PSO

Radiolabelling:

no

Results and discussion

Any other information on results incl. tables

The acute and dermal toxicity of NALCO 01WC026 is low, with the LD50 being > 2000 mg/kg body weight in both cases. The 28 -day toxicity study also revealed that NALCO 01WC026 has a relatively low toxicity, with a NOAEL of 1000 mg/kg/day. Therefore an extensive toxicokinetic assessment is considered of limited value. Below, an assessment of the anticipated toxicokinetic behaviour of NALCO 01WC026 is given.

The water solubility of Nalco 01WC026/PSO is high (> 1000 g/L), caused by the presence of the strongly polar phosphorous and carboxylic acid groups. The strong polarity of these groups makes it very unlikely that this compound easily passes the gastrointestinal wall. Therefore, it is to be expected that the oral bioavailability, and thus systemic exposure, of NALCO 01WC026/PSO will be low.

In the case absorption of NALCO 01WC026/PSO occurs, extensive conjugation of the carboxylic acid groups is anticipated, but also oxidation of the aliphatic groups followed by a rapid sulphation or glucuronidation may occur. The resulting metabolites, as well as the parent compound will be extensively excreted via urine and/or bile.

NALCO 01WC026/PSO will show a low volume of distribution equalling extracellular body water (approximately 0.7 litres per kg body weight). Accumulation is fatty tissues is not anticipated. The plasma protein binding is expected to be low.

Since the bioavailability of dermally applied compounds can be assumed to be zero for substances with a log Pow between -1 and over 5 or a relative molecular mass over 700, it is not expected that NALCO 01WC026 will be absorbed through the skin.

Based on the expected kinetic behaviour in the body, as described above, NALCO 01WC026/PSO will hardly be absorbed after oral administration, because of the presence of strongly polar groups in the molecule. If absorption occurs, NALCO 01WC026/PSO will be extensively metabolised in the liver. Therefore, accumulation in the body during prolonged exposure is not anticipated.

This is supported by the absence of systemic toxicity observed in both the acute and subacute toxicity studies.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information): no bioaccumulation potential based on study results