Registration Dossier

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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Administrative data

Link to relevant study record(s)

Description of key information

No toxicokinetic data (animal or human studies) are available on this substance.

 

Based on the moderate molecular weight (380.24 g/mol), water solubility (3.41 mg/L), and partition coefficient (log Kow 3.41 mg/L at 20°C), it can be expected that oral absorption would be favorable but to a limited extent. The acute oral toxicity study performed showed no adverse effects with LD50 established as greater than 2000 mg/kg body weight. In a combined repeated dose toxicity with the reproductive/developmental toxicity screening test, T002078 did not reveal parental toxicity and no reproduction and developmental toxicity was observed for treatment up to 1000 mg/kg. Based on the low volatility and large MMAD (>100µm), the absorption of T002078 through inhalation is expected to be low. The dermal absorption factor for T002078 is set to 50 % based on the fact that the substance is a solid, its water solubility and log Kow are moderate. Futhermore T002078 is considered non-irritant and non sensitizing.

Key value for chemical safety assessment

Absorption rate - oral (%):
50
Absorption rate - dermal (%):
50
Absorption rate - inhalation (%):
50

Additional information

T002078 (CAS 122584-18-3) is a white, brown grey powder with a moderate molecular weight (380.24 g/mol), a particle size of 128.076 µm (Mass Median Aerodynamic Diameter or MMAD), a moderate water solubility (3.41 mg/L at 20°C), a moderate partition coefficient (log Kow of 2.7 at 20°C ) and a low volatility (vapour pressure of < 2.1 E-11 kPa at 25°C).

The backbone of T002078 is formamide with a 4-hydroxyphenylethyl group and a 2-bromo-5-hydroxy-4-methoxybenzyl attached to the nitrogen atom. Due to the presence of a phenol functional group, the compound is considered a weak acid. The pKa value was calculated to be 9.3-9.9 (Brekelmans, 2017) and the substance is expected not to ionize at neutral pH.

No toxicokinetic data (animal or human studies) are available on this substance. The data present in this dossier are based on physicochemical and toxicological parameters and will allow a qualitative assessment of the toxicokinetic behaviour of T002078.

Absorption

Oral/GI absorption:

T002078 is considered favorable for absorption since its molecular weight < 500 g/mol, its log Pow value between -1 and 4 and its moderate water solubility leading to dissolution of the substance into the gastrointestinal fluids and absorption through passive diffusion. It is generally assumed that the absorption along the gastrointestinal tract predominantly takes place in the small intestine.

In anacute oral toxicitystudy (OECD 423; Latour, 2016), T002078 was administered via oral gavage on a single occasion to 2 subsequent groups of 3 female Wistar rats at 2000 mg/kg bw. No mortality or abnormalities were observed at gross pathology. Hunched posture, piloerection and uncoordinated movements were noted for all animals between days 1 or 4. No adverse effects were demonstrated with LD50 established as greater than 2000 mg/kg bw.

 

In acombined repeated dose toxicity with the reproductive/developmental toxicity screeningtest (OECD 422, Pels Rijcken,2017), T002078 was administered by daily oral gavage to male and female Wistar Han rats at dose levels of 110, 330 and 1000 mg/kg bw/day. T002078 did not reveal parental toxicity and no reproduction and developmental toxicity was observed for treatment up to 1000 mg/kg bw/d.

 

Based on the physicochemical properties and the results of the toxicity studies,the oral absorption factor is considered 50%.

 

Respiratory absorption:

Because T002078 has a low volatility, the availability of the powder for inhalation as a vapour is limited. As its MMAD is larger than 100 µm, the majority of the solid particles will not be inhaled. Based on the above, the absorption of T002078 through inhalation is expected to be low. 

Its lipophilic character (logKow>0) implies that the product has the potential to be subsequently absorbed across the respiratory tract epithelium by passive diffusion. However,the moderate water solubility and the molecular weight higher than 200 g/mol will cause the substance to be retained within the mucus and transported out of the respiratory tract rather than being absorbed after inhalation.

Therefore, therespiratory absorption factor is considered 50%.

 

Dermal absorption:

Since T002078 is a solid, the uptake of the product will be more limited compared to liquid products. The dry product has to dissolve into the surface moisture of the skin before uptake can take place. Based on its moderate water solubility, dermal uptake is expected to be moderate since the substance is sufficiently soluble in water to partition from the stratum corneum into the epidermis. From its moderate log Kow value, it can be derived that the substance is rather lipophilic and therefore easily crosses the lipid rich environment of the stratum corneum leading to dermal uptake.

The substance demonstrated not to irritate the skin based on anin vivoacute dermal irritationstudy (OECD 404; Sanders; 2005).

In aLocal Lymph Node Assay(equivalent to OECD guideline 429; Sanders, 2005), beside the fact the test item was not considered a sensitizer under the conditions of the test, no signs of systemic toxicity were noted.

Based on the absence of dermal toxic effects in the in vivo skin irritation study and the fact that the substance does not meet the criteria for classification for acute toxicity or STOT SE by the oral route, no acute dermal toxicity study was conducted.

 

Based on the available information, the dermal absorption factor is considered 50%.

 

Distribution

Due to its moderate water solubility and moderate molecular weight T002078 is expected to distribute through the body due to diffusion through aqueous channels and pores. Since the substance is lipophilic (log Kow >0 at pH 7), the substance is likely to distribute into cells leading to a higher intracellular concentration in comparison to the extracellular concentration particularly in fatty tissues.

 

Accumulation

Since T002078 is a moderately water-soluble compound and has a log Kow of 2.7, no or only limited accumulation is expected within the body.

 

Metabolism

Once absorbed, T002078 might undergo phase I biotransformation (including dealkylation, reduction or hydroxylation) followed by conjugation reactions (phase II) such as glucuronidation and sulfation, increasing the hydrophilicity. 

 

Excretion

Given the moderate molecular weight and moderate water solubility, T002078 and its possible metabolites (such as conjugated glucuronides) will most likely be excreted through the urine. Most of the metabolites will have been filtered out of the blood by the kidneys, though a small amount may enter the urine directly by passive diffusion. Furthermore, T002078 may also be actively secreted through the bile.