Copper, [29H,31H-phthalocyaninato(2-)-N29,N30,N31,N32]-, (1,3-dihydro-1,3-dioxo-2H-isoindol-2-yl)methyl derivs.

Endpoint summary

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

basic toxicokinetics in vivo

Type of information:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Study period:

2014

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Reason / purpose for cross-reference:

reference to same study

Objective of study:

other: distribution in plasma and liver

Principles of method if other than guideline:

Copper-content was determined in plasma and liver samples of rats that had been given gavage doses for 14 days at doses of 300 and 1000 mg/kg bw.

GLP compliance:

no

Radiolabelling:

no

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Laboratories, Research Models and Services, Germany GmbH, Sulzfeld, Germany
- Age at study initiation: 42 +/- 1 days
- Weight at study initiation:
- Fasting period before study: none
- Housing: single
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: at least five days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-24°C
- Humidity (%): 30 - 70%
- Air changes (per hr): 15
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: 2014-06-09 To:2014-06-24

Route of administration:

oral: gavage

Vehicle:

other: dnnkmg water containing 0.5% carboxymethylcellulose with about 5 mg/100 ml Cremophor EL

Details on exposure:

PREPARATION OF DOSING SOLUTIONS: Daily
The substance is a homogenous suspension.

Duration and frequency of treatment / exposure:

14 days

Remarks:

Doses / Concentrations:
300 andd 1000 mg/kg bw

No. of animals per sex per dose / concentration:

5

Control animals:

yes, concurrent vehicle

Positive control reference chemical:

A 14-day gavage study with an acid-labile copper-pigment (CAS 15680-42-9) was performed in the same year and this study showed a strong increase in liver copper content. (Plasma concentrations were not determined.)

Details on study design:

see endpoint study record for repeated dose toxcity

Details on dosing and sampling:

The determination of copper concentrations in EDTA plasma samples after were performed at the test facility.
The total concentrations of the test substance in plasma were calculated indirectly from the determined copper concentrations (inductively-coupled-plasma mass-spectrometry; experimental error + /- 0,2 mg/kg Cu).
This part of the study was carried out in compliance with the Principles of Good Laboratory Practice.
On study day 15, EDTA blood samples (about 200 μL) were collected from fasted animals by puncturing the retro-bulbar venous plexus under isoflurane anesthesia. After plasma preparation, the samples were frozen at about -80°C prior to analysis.

Liver samples were frozen at about -80°C prior to analysis.

Type:

other: distribution to liver and plasma

Results:

No increase in plasma and liver copper concentration was detected.

Details on distribution in tissues:

No increase in plasma and liver copper concentration was detected (see tables 1 and 2).

Metabolites identified:

not measured

Conclusions:

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

Executive summary:

Table 1: Copper content in liver samples

	animal no.	g liver	mg Copper	mg/g liver	mean (n = 5)
	1	2.043	0.011	5.38	5.54
males	2	2.021	0.011	5.44
control	3	2.2772	0.013	5.71
	4	1.9791	0.012	6.06
	5	1.9656	0.01	5.09
	6	2.2573	0.014	6.20	6.01
males	7	1.63	0.01	6.13
300 mg/kg bw	8	1.5929	0.008	5.02
	9	2.0888	0.012	5.74
	10	2.0201	0.014	6.93
	11	2.1328	0.011	5.16	5.31
males	12	1.9677	0.011	5.59
1000 mg/kg bw	13	1.2978	0.007	5.39
	14	1.977	0.011	5.56
	15	2.4663	0.012	4.87
	16	1.3527	0.008	5.91	6.15
females	17	1.2401	0.008	6.45
control	18	1.2873	0.008	6.21
	19	1.3878	0.008	5.76
	20	1.2479	0.008	6.41
	21	1.245	0.008	6.43	6.41
females	22	1.1989	0.008	6.67
300 mg/kg bw	23	1.3348	0.009	6.74
	24	1.5306	0.009	5.88
	25	1.2649	0.008	6.32
females	26	1.2009	0.007	5.83	6.16
1000 mg/kg bw	27	1.2749	0.009	7.06
	28	1.2284	0.007	5.70
	29	1.3773	0.008	5.81
	30	1.2447	0.008	6.43

Table 2: Copper content in plasma samples

	animal no.	mg/kg	mean
	1	1	1.28
males	2	1.3
control	3	1.3
	4	1.1
	5	1.7
	6	2.1	1.48
males	7	1.1
300 mg/kg bw	8	1.5
	9	1.2
	10	1.5
	11	1.5	1.4
males	12	1.1
1000 mg/kg bw	13	1.5
	14	1.4
	15	1.5
	16	1	1.18
females	17	1
control	18	1.3
	19	1.1
	20	1.5
	21	1.5	1.4
females	22	1.1
300 mg/kg bw	23	1
	24	1.5
	25	1.9
females	26	1.3	1.52
1000 mg/kg bw	27	2.3
	28	1
	29	1.1
	30	1.5

Reference 2

Endpoint:

basic toxicokinetics in vivo

Type of information:

migrated information: read-across based on grouping of substances (category approach)

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Well documented and acceptable study with the following restrictions: A 91 day subchronic dosed feed toxicity study was conducted in rats, similar to OECD Guideline 408 (Subchronic Oral Toxicity - Rodent: 90-day Study), but not a toxicokinetics study (similar to OECD Guideline 417). However, the study additionally included the examination of systemic copper absorption after exposure to the test material, analyzed in livers and kidneys of the animals.

Reason / purpose for cross-reference:

reference to same study

Objective of study:

distribution

Qualifier:

equivalent or similar to guideline

Guideline:

other: OECD Guideline 408 (Subchronic Oral Toxicity - Rodent: 90-day Study)

Deviations:

yes

Principles of method if other than guideline:

This subchronic toxicity study, similar to OECD Guideline 408, was conducted to assist in selecting Maximum Tolerated Dosages (MTD) for a 104 week chronic study in a dosed feed subchronic study. Additionally the study examined, whether or not systemic absorption of copper occured after exposure to the test material. Copper analyses were conducted in livers and kidneys of the animals.

GLP compliance:

no

Radiolabelling:

no

Species:

rat

Strain:

Fischer 344

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Harlan Industries
- Weight at study initiation: males: 70 - 105 g; females: 70 - 100 g
- Housing: polycarbonate cages: groups of 5 rats per cage
- Diet: weighed portions of Purina Lab Chow in meal form, mixed together with weighed portions of the test material (see details at "doses/concentrations")
- Water: ad libitum
- Acclimation period: 15 days

ENVIRONMENTAL CONDITIONS
- Temperature: 21 - 23 °C
- Humidity: 40 - 60 %
- Air changes: at least 15 per hour
- Photoperiod: 12 hrs dark / 12 hrs light

Route of administration:

oral: feed

Vehicle:

other: 12 % water was added to the test material as a dust control agent

Details on exposure:

Dose levels of 5.0, 2.5, 1.25, 0.6 and 0.3 % (w/w) were selected for both males and females. The selected doses were prepared by mixing weighed portions of purina Lab Chow in meal form with weighed portions of the test material. 12 % water was added to the test material as a dust control agent prior to mixing with the meal. For each dose level, one weekly lot of 4500 g (+ 12 % water compensation) was prepared.

The actual mixtures were composed of the following ingredients:
- Dose level 5.0 % (w/w): 252 g test material and water + 4275 g meal
- Dose level 2.5 % (w/w): 126 g test material and water + 4387.5 g meal
- Dose level 1.25 % (w/w): 63 g test material and water + 4443.75 g meal
- Dose level 0.6 % (w/w): 30.24 g test material and water + 44735 g meal
- Dose level 0.3 % (w/w): 15.12 g test material and water + 4486.5 g meal

Each diet was mixed in a Patterson-Kelly twin shelled V blender for 15 min.
The doses were mixed one or two days prior to the week of their use in the study, and stored at 23 °C.
One analysis was perfomed to determine the accuracy of the mixture concentration.

Duration and frequency of treatment / exposure:

90 days

Remarks:

Doses / Concentrations:
Males and females: 0.3, 0.6, 1.25, 2.5, 5 % in diet; (approx. 0, 250, 500, 1100, 2200 and 4500 mg/kg bw for both sexes [based on 16.4 g/d average food consumption, 0.182 kg average bw for males and on 11.55 g/d average food consumption, 0.130 kg average bw] for females).

No. of animals per sex per dose / concentration:

10 males per dose and 10 females per dose

Control animals:

yes, plain diet

Details on study design:

The concentrations of the chemical mixture were the same for male and female rats. All dose levels were prepared on a weight per weight basis. There were 5 dose level groups with 10 individuals of each sex in each dosage and control group. Each dosed group received 90 consecutive days of dosed feed mixture. After one day of observation, the animals were necropsied. Animals were observed twice each day for clinical signs, with at least 6 hours between observations. All observations were recorded daily. Additionally, blood sampling was conducted from 10 control rats, 6 males and 4 females.

Copper analyses were completed in the liver and kidney tissues and the formalin preserving those tissues from male rats in the highest dose group (5 % w/w) and control groups:
- Tissue samples were prepared for analysis by digesting in 10 ml of concentrated nitric acid until most of the organic material was destroyed. Perchloric acid was then added and the solutions were evaporated to strong fumes, additional nitric acid being added as required. The solutions were then fumed to dryness, the residues were dissolved in 5 % nitric acid and the solutions were diluted to 10 ml.
- Formalin samples were filtered through a Millex-GS 0.22 µm filter unit and 5 ml portions of each sample were prepared for analysis by the procedure used to prepare the tissue samples.
- The samples were then subjected to atomic absorption spectrophotometry to determine copper content:
A Perkin-Elmer Model 5000 atomic absorption spectrophotometer was utilized for the work. A series of 10 ml standard solutions, ranging from 0.05 to 2.0 ppm were prepared in 5 % nitric acid by dilution of a certified standard copper stock solution. These solutions were used to calibrate the instrument, which was programmed to print out data as total microgramms of copper per sample. The prepared sample solutions were used in the same manner as the standards. Concentrations of copper in the tissue samples were calculated by dividing the total microgramms found by the weight of the sample. Concentrations of copper in the formalin samples were calculated on a volume basis.

Details on dosing and sampling:

PHARMACOKINETIC STUDY (distribution)
- Tissues and body fluids sampled: liver and kidneys

Statistics:

Student´s T-test (alpha = 0.05) was used to compare the highest dose group results with control results.

Details on absorption:

No data given.

Details on distribution in tissues:

No statistically significant increase of residual copper incorporation was neither reported for the liver tissues (2.82 ppm +- 0.34 ppm) nor for the kidney tissues (5.62 ppm +- 0.49 ppm) of the treated male rats of the highest dose group, compared to residual copper incorporation found in controls (liver 2.78 ppm +- 0.51 ppm; kidney 5.30 ppm +- 0.83 ppm). From all the formalin analyses performed, the authors drawed the conclusion that no detectable levels of copper were leached from the preserved tissue into the formalin bath.

Details on excretion:

No data given.

Metabolites identified:

not measured

Details on metabolites:

No data given.

Table 1: Copper determinations in tissues and formalin of male rats from the subchronic study, treated with the test material for 90 days

male animal #	ppm copper
	liver	kidney	formalin	remark
highest dose group (5 % w/w)
1	4.6 - 4.3*	8.4	0.1	* results of 2 analyses
2	5.9	12.3	0.1
3	4.1 - 4.4*	8.6 - 10.1*	0.1	* results of 2 analyses
4	6.4	7.7	0.1
5	3.2	6.7	0.1
6	3.5	5.8	0.1
7	3.7	8.1	0.1
8	3.5 - 4.1	8.1	0.1
9	3.1	8.7 - 8.6*	0.1	* results of 2 analyses
10	4.6 - 4.5	7.2	0.1
control
1	3.1	3.7 - 4.0*	0.1	* results of 2 analyses
2	3.3	4.1	0.1
3	3.2	4.9 - 4.6*	0.1	* results of 2 analyses
4	3.7 - 4.0*	5.1	0.1	* results of 2 analyses
5	3.0	4.1	0.1
6	2.8	5.4	0.1
7	2.9	2.9 - 3.4*	0.1	* results of 2 analyses
8	2.6	5.5	0.1
9	2.6	5.4	0.1
10	3.3 - 3.6*	5.4	0.1	* results of 2 analyses

Conclusions:

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

Reference 3

Endpoint:

basic toxicokinetics in vivo

Type of information:

migrated information: read-across based on grouping of substances (category approach)

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Well documented and acceptable study with the following restrictions: A 91 day subchronic dosed feed toxicity study was conducted in mice, similar to OECD Guideline 408 (Subchronic Oral Toxicity - Rodent: 90-day Study), but not a toxicokinetics study (similar to OECD Guideline 417). However, the study additionally included the examination of systemic copper absorption after exposure to the test material, analyzed in livers and kidneys of the animals.

Reason / purpose for cross-reference:

reference to same study

Objective of study:

distribution

Qualifier:

equivalent or similar to guideline

Guideline:

other: OECD Guideline 408 (Subchronic Oral Toxicity - Rodent: 90-day Study)

Principles of method if other than guideline:

This subchronic toxicity study, similar to OECD Guideline 408, was conducted to assist in selecting Maximum Tolerated Dosages (MTD) for a 104 week chronic study in a dosed feed subchronic study. Additionally the study examined, whether or not systemic absorption of copper occured after exposure to the test material. Copper analyses were conducted in livers and kidneys of the animals.

GLP compliance:

no

Radiolabelling:

no

Species:

mouse

Strain:

B6C3F1

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Harlan Industries
- Age at study initiation: 8.5 weeks
- Weight at study initiation: males: 16 - 23 g; females: 16 - 19 g
- Housing: polycarbonate cages: groups of 5 mice per cage
- Diet: weighed portions of Purina Lab Chow in meal form, mixed together with weighed portions of the test material (see details at "doses/concentrations")
- Water: ad libitum
- Acclimation period: 15 days

ENVIRONMENTAL CONDITIONS
- Temperature: 21 - 23 °C
- Humidity: 40 - 60 %
- Air changes: at least 15 per hour
- Photoperiod: 12 hrs dark / 12 hrs light

Route of administration:

oral: feed

Vehicle:

other: 12 % water was added to the test material as a dust control agent

Details on exposure:

Dose levels of 5.0, 2.5, 1.25, 0.6 and 0.3 % (w/w) were selected for both males and females. The selected doses were prepared by mixing weighed portions of purina Lab Chow in meal form with weighed portions of the test material. 12 % water was added to the test material as a dust control agent prior to mixing with the meal. For each dose level, one weekly lot of 4500 g (+ 12 % water compensation) was prepared.

The actual mixtures were composed of the following ingredients:
- Dose level 5.0 % (w/w): 252 g test material and water + 4275 g meal
- Dose level 2.5 % (w/w): 126 g test material and water + 4387.5 g meal
- Dose level 1.25 % (w/w): 63 g test material and water + 4443.75 g meal
- Dose level 0.6 % (w/w): 30.24 g test material and water + 44735 g meal
- Dose level 0.3 % (w/w): 15.12 g test material and water + 4486.5 g meal

Each diet was mixed in a Patterson-Kelly twin shelled V blender for 15 min.
The doses were mixed one or two days prior to the week of their use in the study, and stored at 23 °C.
One analysis was perfomed to determine the accuracy of the mixture concentration.

Duration and frequency of treatment / exposure:

90 days

Remarks:

Doses / Concentrations:
Males and females: 0.3, 0.6, 1.25, 2.5, 5 % in diet approx. 0, 1000, 2000, 4000, 8000 and 16000 mg/kg bw for males [based on 7.3 g/d average food consumption, 0.023 kg average bw] and approx. 0, 1100, 2200, 4700, 9400 and 18700 mg/kg bw for females [based on 7.1 g/d average food consumption, 0.019 kg average bw], respectively).

No. of animals per sex per dose / concentration:

10 males and 10 females per dose

Control animals:

yes, plain diet

Details on study design:

- 10 animals were used per sex and dose group.
- Five dose levels of 0.0, 0.3, 0.6, 1.25 and 5.0 % in feed were used in this study (approx. 1000, 2000, 4000, 8000 and 16000 mg/kg bw for males [based on 7.3 g/d average food consumption, 0.023 kg average bw] and approx. 1100, 2200, 4700, 9300 and 18700 mg/kg bw for females [based on 7.1 g/d average food consumption, 0.019 kg average bw], respectively).
- The selected doses were prepared by mixing together weighed portions of Purina Lab Chow in meal form with weighed portions of the chemical. 12% water was added to the chemical as a dust control agent prior to mixing with the meal.
- Each dosed group received on 91 consecutive days of dosed feed mixture.
- Mice were necropsied on day 92 and 93.

Copper analyses were completed in the liver and kidney tissues and the formalin preserving those tissues from male mice in the highest dose group (5 % w/w) and control groups:
- Tissue samples were prepared for analysis by digesting in 10 ml of concentrated nitric acid until most of the organic material was destroyed. Perchloric acid was then added and the solutions were evaporated to strong fumes, additional nitric acid being added as required. The solutions were then fumed to dryness, the residues were dissolved in 5 % nitric acid and the solutions were diluted to 10 ml.
- Formalin samples were filtered through a Millex-GS 0.22 µm filter unit and 5 ml portions of each sample were prepared for analysis by the procedure used to prepare the tissue samples.
- The samples were then subjected to atomic absorption spectrophotometry to determine copper content:
A Perkin-Elmer Model 5000 atomic absorption spectrophotometer was utilized for the work. A series of 10 ml standard solutions, ranging from 0.05 to 2.0 ppm were prepared in 5 % nitric acid by dilution of a certified standard copper stock solution. These solutions were used to calibrate the instrument, which was programmed to print out data as total microgramms of copper per sample. The prepared sample solutions were used in the same manner as the standards. Concentrations of copper in the tissue samples were calculated by dividing the total microgramms found by the weight of the sample. Concentrations of copper in the formalin samples were calculated on a volume basis.

Statistics:

Student´s T-test (alpha = 0.05) was used to compare the highest dose group results with control results.

Preliminary studies:

No data given.

Details on absorption:

No data given.

Details on distribution in tissues:

Slight, but statistically significant increases of copper incorporation were reported in the liver tissues (3.98 ppm +- 1.16 ppm; p < 0.05) and kidney (7.47 ppm +- 2.86 ppm; p < 0.05) tissues of treated male animals of the highest dose group, compared to controls (liver: 3.0 ppm +- 0.34 ppm; kidney: 4.66 ppm +- 0.6 ppm). From all the formalin analyses performed, the authors drawed the conclusion that no detectable levels of copper were leached from the preserved tissue into the formalin bath.
However, an evaluation of the results was conducted by expert judgement and the author draw the following conclusions:
The results of the study do not provide unequivocal evidence for a lack of absorption of the test material. However, the total lack of findings during the 13 week study, coupled with the insolubility of the test material and the minimal changes in tissue copper residues strongly suggests that the test material was not appreciably absorbed.

Details on excretion:

No data given.

Metabolites identified:

not measured

Details on metabolites:

No data given.

Table 1: Copper determinations in tissues and formalin of male mice from the subchronic study, treated with the test material for 91 days

male animal #	ppm copper
	liver	kidney	formalin	remark
highest dose group (5 % w/w)
1	7.0	14.5	--
2	3.2-3.6 *	6.8	--	* results of 2 analyses
3	3.4	7.7	--
4	3.4	4.8	--
5	3.5	6.3	--
6	3.7	7.3	--
7	3.9	6.4	--
8	4.1	8.2	--
9	3.3-3.6 *	5.2	--	* results of 2 analyses
control
1	3.5	4.2	0.1
2	3.1	3.8	0.1
3	3.1	4.6	0.1
4	2.8	4.6	0.1
5	2.9	4.2	0.1
6	3.2	4.7	0.1
7	3.2	5.8	0.1
8	2.9	5.3	0.1
9	2.3	4.7	0.1

Conclusions:

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

Description of key information

The substance is an inert high molecular weight organic copper complex.

Based on information on related substances, it is not systemically available after ingestion as indicated by lack of increased plasma and liver copper concentrations upon repeated oral dosing.

Key value for chemical safety assessment

Bioaccumulation potential:

no bioaccumulation potential

Additional information

Copper, [29H,31H-phthalocyaninato(2-)-N29,N30,N31,N32]-, (1,3-dihydro-1,3-dioxo-2H-isoindol-2-yl)methyl derivs. is an isomeric mixture of predominantly monosubstituted copper phthalocyanines. The monosubstituted isomers have a molecular weight of 735 g/mol and are described by the sum formula C41H21CuN9O2. Mass spectrometry shows the presence of higher substituted species up to n=6. The average degree of substitution is 1.4. Impurities are phthalimide, phthalic acid and phthalimidomethylphthalimide.

Toxicokinetic properties are assessed from experimental data on the copperphthalocyanine core (147-14-8) and an UVCB-analogue (CAS 59160-79-1) which consists of the identical components, but has a an average higher degree of substitution ( n = 2.48, range 0 - 3). It has the same impurities. The average mass is 970 g/mol. For data matrices and structures it is referred to the attachment with read-across justification.

The higher substituted analogue UVCB substance is insoluble in water as examined via total organic carbon and copper content (< 2 mg/L) and in octanol (< 1.57 mg/L). The copper phthalocyanine core has a measured water solubility of 0.009 mg/L and an octanol solubility of 0.0004 mg/L.

It is of higher molecular weight compared to the phthalocyanine core and has non-reactive substituents. Since systemic uptake depends on solubilities and size, the target substance is considered to be well-represented by the combination of data on the core and the higher alkylated analogue.

For both substances, the content of copper in in tissues was determined because copper ions are known to accumulate in liver; it can therefore serve as a biomarker for copper-containing substances.

Indeed, a similar 14 -day study with an acid-labile and lower molecular weight organic copper pigment (CAS 15680 -42 -9) showed that a gavage dosing for 14 days resulted in a significant increase in liver copper concentrations. For details it is referred to the dissiminated REACH-dossier of that substance.

For the analogue UVCB substance, a 14 -day study (originally intended as a dose-range-finder study) was performed with additional investigations on copper concentrations in liver and plasma at the end of treatment (BASF 2015). This study was performed with each 5 male and female rats per dose group and included clincal chemistry and haematology parameters. Oral dosing of up to 1000 mg/kg bw of

CAS59160-79-1

did not cause increased copper concentrations in liver and plasma. No blue discoloration of internal tissues were observed. Clinical chemistry and haematology parameters were not affected and overall no adverse effects were noted. From this it is concluded that

CAS59160-79-1

is not taken up by the body after ingestion. Concentrations of copper phthalocyanine were analyzed in liver and kidney of male rats and mice after oral exposure in a subchronic 90-day feeding study (Batelle 1980). The concentrations were 0.3 %, 0.6 %, 1.25 %, 2.5 % and 5 % in the diet for rats (corresponding to approx. 0, 250, 500, 1100, 2200 and 4500 mg/kg bw for both sexes [based on 16.4 g/d average food consumption, 0.182 kg average bw for males and on 11.55 g/d average food consumption, 0.130 kg average bw] for females) and mice (approx. 0, 1000, 2000, 4000, 8000 and 16000 mg/kg bw for males [based on 7.3 g/d average food consumption, 0.023 kg average bw] and approx. 0, 1100, 2200, 4700, 9400 and 18700 mg/kg bw for females [based on 7.1 g/d average food consumption, 0.019 kg average bw], respectively), administered on 90 consecutive days. The liver and kidney tissues from the highest dose and from controls of male animals were dissolved in nitric acid and subsequently analyzed for copper by atomic absorption spectrophotometry. No statistically significant increases of copper incorporation were reported in the liver (2.82 ppm +- 0.34 ppm vs. 2.78 ppm +- 0.51 ppm) and kidney (5.62 ppm +- 0.49 ppm vs. 5.30 ppm +- 0.83 ppm) tissues of treated male rats of the highest dose group, compared to control animals. Therefore, the authors strongly suggested that the test material was not absorbed under the test conditions chosen. Slight, but statistically significant increases of copper incorporation were reported in the liver (3.98 ppm +- 1.16 ppm vs. 3.0 ppm +- 0.34 ppm) and kidney (7.47 ppm +- 2.86 ppm vs. 4.66 ppm +- 0.6 ppm) tissues of treated male mice, compared to control animals.

Considering the insolubility, the high molecular weight and the absence of copper accumulation observed for the core structure after 90 days and the higher subsituted UVCB-analogue after 14days it is concluded that the substance is not taken up after ingestion. Likewse, skin permeability is not expected.