Resin acids and Rosin acids, hydrogenated, calcium salts

Endpoint summary

Key value for chemical safety assessment

Effects on fertility

Description of key information

Five key screening reproductive/developmental toxicity studies (OECD 422) conducted with Rosin; Rosin, hydrogenated; Rosin oligomers; and Rosin, reaction products with formaldehyde were identified.

The reproductive toxicity NOAEL for Tall Oil Rosin was determined to be 10000 ppm, the highest concentration tested (Harlan Laboratories Ltd., 2015a).

The reproductive toxicity NOAEL for Rosin, hydrogenated was determined to be 10000 ppm, the highest concentration tested (Harlan Laboratories Ltd., 2015b).

The reproductive toxicity NOEL for Rosin, reaction products with formaldehyde was determined to be 10000 ppm, the highest concentration tested (Harlan Laboratories Ltd., 2015c). No reproductive/developmental toxicity effects were observed in this study at concentrations up to 10000 ppm.

The reproductive toxicity NOAEL for Gum Rosin was determined to be 5000 ppm, based on a reduction in corpora lutea count followed by a lower number of implantation sites and lower mean litter size observed at the 10000 ppm concentration (Harlan Laboratories Ltd., 2014a).

The reproductive toxicity NOAEL for Rosin, oligomers was determined to be 3000 ppm, based on effects on pup body weights observed at the 7500 ppm and 15000 ppm concentration levels (Harlan Laboratories Ltd., 2014b).

Additionally, one key screening reproductive/developmental (OECD 421) study (Inveresk Research, 2003a) was identified conducted with Rosin. No reproductive effects were observed in this study although there was a slight reduction in litter size and slightly reduced pup weight in high dose animals (10,000 ppm in diet).

Effect on fertility: via inhalation route

Endpoint conclusion:

no study available

Effect on fertility: via dermal route

Endpoint conclusion:

no study available

Additional information

In a key combined repeated dose, reproductive/developmental OECD 422 toxicity screening study (Harlan Laboratories Ltd., 2015a), the test material (Tall oil rosin, CAS# 8050-09-7) was administered daily in dietary mixtures at concentrations of 0, 2500 ppm (males - 160 mg/Kg bw/day Pre-Pairing and 136.4 mg/Kg bw/day Post-Pairing; females - 189 mg/Kg bw/day Pre-Pairing; 182.8 mg/Kg bw/day Gestation; and 241.1 mg/K bw/day Lactation), 5000 ppm (males - 301.5 mg/Kg bw/day Pre-Pairing and 276.5mg/K bw/day Post-Pairing; females – 356.1 mg/Kg bw/day Pre-Pairing; 377.3 mg/Kg bw/day Gestation; and 572.7 mg/Kg bw/day Lactation), or 10000 ppm (males - 496.4 mg/Kg bw/day Pre-Pairing and 585.5 mg/Kg bw/day Post-Pairing; females – 612.9 mg/Kg bw/day Pre-Pairing; 772.2 mg/Kg bw/day Gestation; and 1227.9 mg/Kg bw/day Lactation) to male rats for 42 days and to female rats for 14 days prior to pairing, through the pairing and gestation periods until the F1 generation reached day 4 post partum.

 

Treatment resulted in slightly higher test item intake in females compared to males during the pre-pairing period. Intake remained fairly constant throughout the entire study, except during the lactation phase when, due to an increase in food consumption, intake in females was almost two-fold higher than during the preceding gestation period. In the high concentration group (10000 ppm), a reduction in food consumption resulting in body weight loss followed by reduced body weight gain, significantly reduced body weights, and significantly reduced food conversion efficiency were observed in male and female rats. A recovery was observed for food consumption in males and females and for body weight gain and food conversion efficiency in males. In females, body weight gain and food conversion efficiency recovered also initially but both values reduced again during the gestation period and remained lower than the control values during the lactation period. Body weights in both males and females, remained reduced compared to the controls during the entire study. Body weight loss in one female led to premature termination of the animal for humane reasons. In females, effects on water consumption were also noted in the 10000 ppm group; an increase was noted during the gestation period followed by a reduction during the lactation period. Due to the recovery observed during the study and because Tall Oil Rosin (CAS # 8050-09-7) is known to cause palatability problems, effects on food consumption were considered to most probably not be a sign of toxic potential but resulted from unpalatability of the test item. The lower body weights in males of the 10000 ppm group compared to concurrent control throughout the study was considered to represent impaired growth resulting from food aversion during the early treatment period. Similarly, lower body weights in females were considered to result from undernutrition at the beginning of the study. In females, however, a second drop in body weight gain and food consumption efficiency was observed during the gestation period after the recovery of food consumption. These later effects were considered to be related to potential toxicity of the test item. Reduction in body weights in both genders and reductions in body weight gain and food conversion efficiency in females at the high concentration level were considered to be adverse because they were not reversible during the course of the study.

 

Further, terminal examinations revealed increased liver weights in males and females in the 10000 ppm group. This effect was accompanied by an increase in alkaline phosphatase activity but no changes in the blood activity of other liver enzymes were observed and there were no histopathological lesions in this organ in any gender. For these reasons, increased liver weights were considered not to be adverse and probably a result of increased metabolism due to the exposure to foreign compound.

 

In the high concentration group, the number of corpora lutea was reduced, which resulted in slightly, not statistically significant lower number of implantation sites and slightly, not statistically significant lower litter size at first litter check. Mean litter size at the high concentration level remained in the range of historical control values. Slightly reduced body weight and body weight gain were observed in pups during lactation. Although the reduction was only minor and predominantly not statistically significant if compared to the current control, values at the high concentration level were lower if compared to the historical control background and therefore this observation was considered to

be related to the treatment with the test item.

 

Mating performance, fertility, duration of gestation, post-implantation and post-natal loss were considered not to be affected by the treatment with the test item at any concentration level. Due to adverse effects on body weight observed in females in the high concentration group, a possibility that the reduced number of corpora lutea as well as lower pup body weight were secondary to the maternal response, should be taken into consideration.

 

In the intermediate concentration group (5000 ppm), a slight reduction in food consumption was observed in both genders at the beginning of the treatment. In males, this resulted in slight reductions in body weight gain and food conversion efficiency at the beginning of the treatment and slightly, not statistically significant, lower body weights during the entire study. In females, body weight gain and food conversion efficiency were also slightly reduced at the beginning of the study and recovered thereafter whereas body weights were not changed compared to the control values during the entire study. Food conversion efficiency reduced again during the gestation period but recovered and was higher than the control value during the lactation period. Water consumption was slightly and reversibly increased in females of this group. Due to reversibility, effects on food consumption, body weights and water consumption in the intermediate concentration group were considered not to be adverse. Although food conversion efficiency was significantly lower in this group again during the gestation period, it recovered during the lactation period and did not correlate with reduced body weight gain or reduced body weights and therefore this effect was also considered not to be adverse.

 

In the 5000 ppm group, increased liver weights were observed in males and females but without histopathological lesions or changes in related clinical biochemistry parameters and therefore considered not to be adverse. No effects on reproductive or developmental parameters were observed in animals in the 5000 ppm group. In the low concentration group (2500 ppm), no signs of general toxicity in males or females as well as no effects on reproduction or development were observed.

 

Based on these observations, the NOEL (No Observed Effect Level) was established at the concentration level of 2500 ppm and the NOAEL (No Observed Adverse Effect Level) was established at 5000 ppm for general toxicity. For reproductive and developmental toxicity, the NOEL was established at 5000 ppm whereas the NOAEL was established at the concentration level of 10000 ppm, the highest concentration tested in the study.

In a key combined repeated dose, reproductive/developmental toxicity study (OECD 422), the test material (Rosin, hydrogenated; CAS# 65997-06-0) was continuously administered in feed to rats (12/sex/concentration) at concentrations of 0, 1000, 3000, and 10000 ppm. The test material was administered to male rats for 43 days and to female rats for 14 days prior to pairing, through the pairing and gestation periods until the F1 generation reached day 4 post partum (Harlan Laboratories Ltd., 2015b).

 

Test material-related effects were observed in males and females in group 4 (10000 ppm) whereas in groups 2 (1000 ppm) and 3 (3000 ppm) no signs of general toxicity were noted in either gender. Microscopic examination of selected organs revealed pathological changes in groups 2, 3 and 4.

 

In group 4, reduction in food consumption and food conversion efficiency resulting in body weight loss, reduced body weight gain and significantly reduced body weights were observed in both genders. The effect on food consumption was considered to most probably not be a sign of toxic potential but to result from unpalatability of the test item. Food consumption recovered during the study and therefore the effect was considered not to be adverse. Although body

weight gain increased and was similar to the control values after the initial reduction, body weights remained lower than the control group values during the entire study period in males and females. The persistent reduction in body weights was considered to be adverse.

 

An increase in activities of alanine aminotransferase and alkaline phosphatase were measured in the blood of males in group 4. This finding was considered to be indicative of liver cell injury and therefore adverse.

 

Increased liver weights were recorded at necropsy in males in group 4. This finding was correlated histologically with hepatocellular hypertrophy. Increased liver weights and hepatocellular hypertrophy are suggestive of an adaptative response to mixed function oxidase induction. In the pituitary, enlarged vacuolated cells were observed. This change may reflect hypertrophy of thyroid-stimulating hormone-producing cells (thyrotrophs), a common finding following administration of liver enzyme inducers where the underlying mechanism is considered to be increased hepatic clearance of thyroid hormones followed by a compensatory increase in the pituitary secretion of TSH. Further, minimal hypertrophy of zona glomerulosa was observed during microscopic examinations in the adrenal glands of males in groups 3 and 4 and of females in groups 2, 3 and 4. The pathogenesis of this change is uncertain. The zona glomerulosa is the site of synthesis of aldosterone a mineralocorticoid which is mainly involved in the control of salt and water balance in the body. Secretion of aldosterone is controlled through the renin-angiotensin system and hypertrophy of the zona glomerulosa is generally considered to be an adaptative process following stimulation of this system.

 

There were no test item related microscopic findings in the reproductive organs, including the qualitative examination of the stages of spermatogenesis in the testes (no test item related abnormalities in the integrity of the various cell types present within the different stages of the sperm cycle) and the evaluation of the uterus or evaluation of follicles and corpora lutea in the ovaries. There were no test item related microscopic findings in the males or females suspected of reduced fertility.

 

A reduction in corpora lutea count was observed in females ingroup 4 during the macroscopic evaluation at necropsy whereas histopathological evaluation of follicles and corpora lutea in the ovaries did not reveal any test item-related effect. Because no significant changes in the number of implantation sites or litter size were observed during the study, the reduction in corpora lutea count was considered not to be adverse. Further, the effect on corpora lutea count may possibly be secondary to the toxic effects in females observed in this group. Remaining reproduction parameters: mating performance, fertility, duration of gestation, post implantation and postnatal loss were not affected by the treatment with the test item at any dose level.

 

With exception for a slight retardation in pup body weights in the presence of adversely reduced food consumption and body weight in females in group 4, no effects on development were observed during the study. The changes in pup body weights were only minor (not statistically significant if compared to the control group), and values in the high-dose group were close to the normal background range in this rat strain. The reduction in pup body weights represents a delayed growth rather than a developmental disturbance. This effect is commonly seen in the presence of maternal toxicity manifested as decreased food consumption associated with reduced body weights and it is considered to be secondary to the maternal toxicity. For these reasons, effects on pup body weights were considered not to be adverse and likely to be a secondary response.

 

Due to the histopathological changes in adrenal glands, no NOEL (No Observed Adverse Effect Level) for general toxicity was established for females whereas for males it was at the dose level of 1000 ppm. The NOAEL (No Observed Adverse Effect Level) was established at 3000 ppm. For reproduction and developmental toxicity, the NOEL was established at the dose level of 3000 ppm whereas the NOAEL was at 10000 ppm, the highest dose level used in the study.

In a key reproductive/developmental toxicity study (OECD 422), the toxicological effects on rats resulting from continuous dietary oral administration of the test material (Rosin, reaction product with formaldehyde, CAS #. 91081-53-7) were evaluated (Harlan Laboratories Ltd., 2015c). The test material was administered daily in dietary mixtures at concentrations of: 0, 1000, 3000 and 10000 ppm to male rats for 43 days and to female rats for 14 days prior to pairing, through the pairing and gestation periods until the F1 generation reached day 4 post-partum.No unscheduled deaths were recorded during the study period. No clinical signs were recorded. Slight reductions in food consumption and water consumption and low body weight and body weight gain was recorded in males and females of group 4. The effect was likely due to the reduced palatability of the diet at the higher concentration. Slightly low body weights and reduced water consumption were noted in males of groups 2 and 3. Minimal hypertrophy of the zona glomerulosa were observed in the adrenal glands in males and females of groups 3 and 4. The pathogenesis was considered to be an adaptive process following stimulation of this system. Increased liver weights were recorded at necropsy in males and females of group 4 and these findings are suggestive of an adaptive response to mixed function oxidase induction and considered not to be adverse.

 

The sperm motility, morphology and sperm count, estrus cycle, mating performance, fertility, duration of gestation, corpora lutea count, implantation rate, post-implantation and postnatal loss and litter size were not affected by treatment with the test material at any concentration. There were no test material-related findings in pups noted during the first litter check, the first 4 days post-partum or during the necropsy.Based on the result of the study, the NOAEL (No Observed Adverse Effect Level) for general toxicity was established at a concentration of 10000 ppm and the NOEL (No Observed Effect Level) was established at a concentration of 1000 ppm.The NOAEL and NOEL for reproduction/ developmental toxicity were established at a concentration of 10000 ppm, the highest concentration used in the study.

In another key combined repeated dose, reproductive/developmental (OECD 422) toxicity study (Harlan Laboratories Ltd., 2014a), Gum Rosin was administered to rats (12/sex/dose) in dietary mixtures at concentrations of 0, 2500, 5000, and 10000 ppm for a period of 50 days for male rats and to female rats for 14 days prior to pairing, through the pairing and gestation periods until the F1 generation reached day 4 post partum (at least 36 days, up to 53 days).The treatment with the test item did not lead to any premature mortalities and had no effects on behaviour, reflexes, grip strength, locomotor activity, and hematology parameters. Mating performance, fertility index, duration of gestation, and post-implantation loss were not affected by the treatment with the test item at any dose level. No abnormal findings were recorded at the first litter check and at necropsy of the pups. No effects of the treatment on sex ratio and righting reflex were observed.

 

In the high dose group (10000 ppm), in both sexes, significantly lower food consumption was recorded during the first treatment week. From treatment week 2 until the end of the treatment period the food consumption was slightly decreased in males, but still significantly decreased in females when compared to the control group. The lower food consumption led to a transient lower body weight gain and lower body weights until the end of the study in both sexes. Except for ruffled fur in one female from the last day of gestation to the end of the lactation period, no clinical signs were observed. The water consumption was significantly reduced during the lactation period which was possibly due to the lower number of pups and therefore lower milk production in this group.

 

Increased activity of alkaline phosphatase in males and increased bilirubin concentration in both sexes did not correlate with other findings and were therefore not considered adverse. Decreased absolute and relative thymus weights in females recorded at necropsy correlated with decreased lymphocytes in the cortex of the thymus. This finding was considered to be stress-related and likely not a direct effect of the test item.

 

The mean numbers of corpora lutea and implantations per dam as well as the mean litter size at the first litter check were decreased. The postnatal loss was slightly increased. In addition, the male and female pup weights were significantly lower on day 1 and 4 post partum when compared to the controls. Pups from one litter were cold to the touch on days 3 and 4 post partum. The effects on reproduction and pups were considered likely to be secondary to the effects of the treatment on food consumption and body weight development of the dams.

 

In the intermediate dose group (5000 ppm), lower food consumption was recorded in males and females during the first treatment week. From treatment week 2 onwards the food consumption was similar to the control group in males, but still decreased in females. The lower food consumption led to a transient lower body weight gain in males during the pre-paring period. However, decreased body weights compared to the concurrent controls were recorded during the entire treatment period in females. No clinical signs were observed at this dose level. The water consumption of females was slightly reduced during the lactation period.

 

In the low dose group (2500 ppm), a transiently slightly lower body weight gain was recorded during the pre-pairing period in males. Afterwards the body weight development at this dose level was similar to the controls.

 

The creatinine concentration was increased at all dose levels in males. An increase of creatinine is usually a sign for kidney damage. However, no histopathological findings were recorded in the kidneys. Therefore, the increase of the creatinine was not considered to be an adverse effect. Minimal hypertrophy/vacuolation of the zona glomerulosa was observed in the adrenal glands of males from the 2500 ppm group and in females from the 5000 ppm group with dose related-incidence. The pathogenesis of this change is uncertain. The zona glomerulosa is the site of synthesis of aldosterone which is mainly involved in the control of salt and water balance in the body. Secretion of aldosterone is controlled through the renin-angiotensin system and hypertrophy of the zona glomerulosa is generally considered to be an adaptative process following stimulation of this system. Therefore, this change was not considered to be an adverse effect.

 

Based on the results of this study, a NOEL (No Observed Effect Level) for general toxicity could not be established due to effects on body weights at all dose levels in females during the lactation period. The NOAEL (No Observed Adverse Effect Level) for general toxicity was established at the dose level of 2500 ppm. The NOEL and the NOAEL for reproduction/developmental toxicity were established at 5000 ppm.

In another key combined repeated dose, reproductive/developmental toxicity study (OECD 422), the test material (Rosin, oligomers; CAS # 65997-05-9) was administered to rats (12/sex/concentration) in dietary mixtures at concentrations of 0, 3000, 7500 and 15000 ppm (Harlan Laboratories Ltd., 2014b). The test material was continuously administered to male rats for 43 days and to female rats for 14 days prior to pairing, through the pairing and gestation periods until the F1 generation reached day 4 post partum (up to 55 days). Oral exposure to the test material had no effects on behavior, reflexes, grip strength, locomotor activity, and hematology parameters. No clinical signs of toxicological relevance were observed and mating performance, fertility index, and duration of gestation were not affected by the treatment at any concentration level. No test material related abnormal findings were recorded at the first litter check and at necropsy of the pups. No effects of the treatment on sex ratio and righting reflex were observe through the study period.

 

One female rat in the high concentration group was observed in a moribund condition and was sacrificed on treatment day 13. The moribund condition was considered to be caused by the treatment with the test item. In Group 4 females, significantly lower food consumption was recorded during the entire treatment period which led to a lower body weight gain and body weights through the entire treatment period. In Group 4 males, the food consumption was reduced during the pre-pairing period which led to a lower body weight gain during the pre-pairing and pairing period. The body weights of the males were decreased during the entire treatment period. The water consumption of females was decreased during the entire treatment period, but was not altered in males.

 

Increased activity albumin concentration in both sexes, increased bilirubin concentration in females and increased triglyceride concentration in females were observed in the high concentration animals. While these effects were considered test material-related, they did not clearly correlate with other findings and were therefore not considered adverse. Increased liver weights were observed in both sexes were correlated microscopically with minimal centrilobular hepatocellular hypertrophy. These findings are suggestive of an adaptative response to mixed function oxidase induction. Decreased adrenal weights were also observed in both sexes in the high concentration group animals. Minimal hypertrophy of the zona glomerulosa was observed in the adrenal glands of female rats. The pathogenesis of this change is uncertain. The zona glomerulosa is the site of synthesis of aldosterone, a mineralocorticoid which is mainly involved in the control of salt and water balance in the body. Secretion of aldosterone is controlled through the renin-angiotensin system and hypertrophy of the zona glomerulosa is generally considered to be an adaptative process following stimulation of this system.

 

The mean numbers of corpora lutea and implantations per dam were decreased and the total number of post implantation losses was significantly higher in Group 4 females than in the control group. This led to a lower mean number of living pups per litter at the first litter check. In addition, the body weight gain of male and female pups was significantly lower on day 4 post partum when compared to the controls. These observations could be secondary to lower maternal food consumption and body weight gain in this group.

 

In the intermediate concentration Group (Group 3), decreased food consumption was recorded during the first four treatment days in females which led to a lower body weight gain during the pre-pairing period and decreased body weights through the entire treatment period. In males, the food consumption was slightly reduced during the pre-pairing period which led to a lower body weight gain during the pre-pairing period and lower body weights until the end of the study. Increased liver weights were observed in both sexes correlated microscopically with minimal centrilobular hepatocellular hypertrophy in males. Minimal hypertrophy of the zona glomerulosa in the adrenal glands of females and decreased adrenal weights in males were also observed. Significant lower mean body weight gain was recorded on day 4 post partum in pups of both sexes.

 

In Group 2 (3000 ppm), slightly lower body weight gain was observed during the first four days of treatment at the beginning of the pre-pairing period and slightly increased liver weights in males were observed. No other test material-related effects were recorded. Based on the results of this study, a NOEL (No Observed Effect Level) for systemic toxicity could not be established due to effects on body weight gain and liver weights at all dose levels in males. The NOAEL (No Observed Adverse Effect Level) for systemic toxicity was established at 7500 ppm due to a test item-related moribundity, necessitating euthanasia, at the high concentration. The NOEL and the NOAEL for reproductive/developmental toxicity was determined to be 3000 ppm.

In a reproductive and developmental toxicity screening study conducted according to OECD Guideline 421 (Inveresk Research, 2003a), male and female Sprague Dawley rats were exposed to 0, 1000, 3000 or 10,000 ppm Gum Rosin (Rosin) in the diet during pre-mating, mating, gestation and lactation for a total of 30 exposure days for males and 41-45 exposure days for females. At 10,000 ppm in the diet (equivalent to 786 mg/kg bw/f for males and 869 mg/kg bw/d for females), there were no test material-related effects on mating performance, male and female fertility indices, or length of gestation and no gross or microscopic effects on reproductive organs of either sex. The mean number of implant sites per pregnancy was slightly reduced resulting in a slight reduction in litter size. Mean litter and pup weights were also slightly reduced. The effect on implantation, litter size and fetal weight may be secondary to the effects on decreased food intake and subsequent lower weight gain observed in the adult females. A NOAEL of 3000 ppm, equivalent to 248 (males) to 309 (females) mg/kg bw/d was derived from this study.

In guideline repeat exposure studies (OECD 408), there were no gross or microscopic changes in reproductive organs of male or female rats exposed to Rosin; Rosin, hydrogenated; or Rosin, reaction products with formaldehyde for a period of 90 days.

Effects on developmental toxicity

Description of key information

One key pre-natal developmental toxicity study (OECD 414) was identified conducted with Rosin (Envigo Research Limited, 2017c). In-utero survival of the developing conceptus was unaffected by maternal exposure at 7500 ppm, although reduced foetal and placental weights indicated an adverse effect on foetal growth. The absence of any structural defects indicated that development per se was unaffected at this dietary exposure level. The ‘No Observed Adverse Effect Level’ (NOAEL) for foetal developmental toxicity was considered to be 5000 ppm (equivalent to a mean achieved dosage of 387.2 mg/kg bw/day).

Five key screening reproductive/developmental toxicity studies (OECD 422) conducted with Rosin; Rosin, hydrogenated; Rosin oligomers; and Rosin, reaction products with formaldehyde were identified.

The developmental toxicity NOEL for Rosin was established at 5000 ppm, whereas the NOAEL was established at the concentration level of 10000 ppm, the highest concentration tested in the study (Harlan Laboratories Ltd., 2015a).

The developmental toxicity NOEL for Rosin, hydrogenated was established at the dose level of 3000 ppm whereas the NOAEL was at 10000 ppm, the highest dose level used in the study (Harlan Laboratories Ltd., 2015b).

The developmental toxicity NOEL and NOAEL for Rosin, reaction products with formaldehyde were established at a concentration of 10000 ppm, the highest concentration used in the study (Harlan Laboratories Ltd., 2015c).

The developmental toxicity NOEL and NOAEL for Gum Rosin were established at 5000 ppm, based on mortality and body weight effects observed at the 10000 ppm concentration level (Harlan Laboratories Ltd., 2014a).

The developmental toxicity NOEL and NOAEL for Rosin, oligomerswere determined to be 3000 ppm, based on effects on pup body weight at concentrations of 7500 and 15000 ppm (Harlan Laboratories Ltd., 2014b).

One key screening reproductive/developmental (OECD 421) was identified conducted with Rosin (Inveresk Research, 2003a). No developmental effects were observed in this study although there was a slight reduction in litter size in high dose dams (10,000 ppm in diet).

Effect on developmental toxicity: via oral route

Endpoint conclusion:

adverse effect observed

Dose descriptor:

NOAEL

387.2 mg/kg bw/day

Study duration:

subacute

Species:

rat

Effect on developmental toxicity: via inhalation route

Endpoint conclusion:

no study available

Effect on developmental toxicity: via dermal route

Endpoint conclusion:

no study available

Additional information

In a key pre-natal developmental toxicity study (Envigo Research Ltd., 2017c), the test material (Rosin, CAS# 8050-09-7) was administered by continuous dietary admixture to three groups each composed of twenty-four time mated Sprague-Dawley Crl:CD®(SD) IGS BR strain rats, between gestation days 3 and 19 (inclusive) at dietary concentrations of 2500, 5000, or 7500 ppm (equivalent to mean achieved dosages of 199.3, 387.2 or 561.1 mg/kg bw/day respectively). A further group of twenty-four time mated females was fed basal laboratory diet to serve as a control.

 

Clinical signs, body weight change, food and water consumptions were monitored during the study. All females were terminated on gestation day 20 and subjected to gross necropsy including examination of the uterine contents. The number of corpora lutea, number, position and type of implantation, placental weights, foetal weight, sex and external and internal macroscopic appearance were recorded. Half of the pups from each litter were examined for detailed skeletal development and the remainder were subjected to detailed visceral examination.

 

The oral administration of the test material to pregnant rats by continuous dietary exposure was associated with lower maternal body weight gain during gestation and an initial effect on food consumption at 7500 ppm and lower maternal body weight gain at 5000 ppm. No similar effects were apparent at 2500 ppm (equivalent to a mean achieved dosage of 199.3 mg/kg bw/day) which was considered to represent the No Observed Adverse Effect Level (NOAEL) for the pregnant female.

 

In-utero survival of the developing conceptus was unaffected by maternal exposure at 7500 ppm, although reduced foetal and placental weights indicated an adverse effect on foetal growth. The absence of any structural defects indicated that development per se was unaffected at this dietary exposure level. At 5000 or 2500 ppm no adverse treatment-related changes were detected in the offspring parameters measured or on embryofoetal development. The ‘No Observed Adverse Effect Level’ (NOAEL) for foetal developmental toxicity was therefore considered to be 5000 ppm (equivalent to a mean achieved dosage of 387.2 mg/kg bw/day).

 

The potential for Rosin (Tall oil rosin, CAS# 8050-09-7) has been evaluated in a reproductive/developmental toxicity study conducted according to OECD Guideline 422, in which the test material was administered daily in dietary mixtures at concentrations of 0, 2500 ppm, 5000 ppm, or 10000 ppm to male rats for 42 days and to female rats for 14 days prior to pairing, through the pairing and gestation periods until the F1 generation reached day 4 post-partum.

For developmental toxicity, the NOEL was established at 5000 ppm, based on slightly reduced body weight and body weight gain observed in pups during lactation in the 10000 ppm concentration group. Although the reduction was only minor and predominantly not statistically significant if compared to the current control, values at the high concentration level were lower if compared to the historical control background and therefore this observation was considered to be related to the treatment with the test item. The NOAEL for developmental toxicity was established at the concentration level of 10000 ppm, the highest concentration tested in the study (Harlan Laboratories Ltd., 2015a). 

 

The potential for Rosin, hydrogenated (CAS# 65997-06-0) has been evaluated in a reproductive/developmental toxicity study conducted according to OECD Guideline 422, in which the test material was continuously administered in feed to rats (12/sex/concentration) at concentrations of 0, 1000, 3000, and 10000 ppm. The test material was administered to male rats for 43 days and to female rats for 14 days prior to pairing, through the pairing and gestation periods until the F1 generation reached day 4 post-partum. For developmental toxicity, the NOEL was established at the dose level of 3000 ppm, based on a slight retardation in pup body weights in the presence of adversely reduced food consumption and body weight in females in the high concentration group. No effects on development were observed during the study. The changes in pup body weights were only minor (not statistically significant if compared to the control group), and values in the high-dose group were close to the normal background range in this rat strain. The reduction in pup body weights represents a delayed growth rather than a developmental disturbance. This effect is commonly seen in the presence of maternal toxicity manifested as decreased food consumption associated with reduced body weights and it is considered to be secondary to the maternal toxicity. For these reasons, effects on pup body weights were considered not to be adverse and likely to be a secondary response. Therefore, the NOAEL for developmental toxicity was determined to be 10000 ppm, the highest dose level used in the study (Harlan Laboratories Ltd., 2015b).

The potential for Rosin, reaction products with formaldehyde has been evaluated in a reproductive/developmental toxicity study conducted according to OECD Guideline 422, in which the test material was administered daily in dietary mixtures at concentrations of: 0, 1000, 3000 and 10000 ppm to male rats for 43 days and to female rats for 14 days prior to pairing, through the pairing and gestation periods until the F1 generation reached day 4 post-partum. No unscheduled deaths were recorded during the study period. No clinical signs were recorded. Slight reductions in food consumption and water consumption and low body weight and body weight gain was recorded in males and females of group 4. The effect was likely due to the reduced palatability of the diet at the higher concentration. Slightly low body weights and reduced water consumption were noted in males of groups 2 and 3. Minimal hypertrophy of the zona glomerulosa were observed in the adrenal glands in males and females of groups 3 and 4. The pathogenesis was considered to be an adaptive process following stimulation of this system. Increased liver weights were recorded at necropsy in males and females of group 4 and these findings are suggestive of an adaptive response to mixed function oxidase induction and considered not to be adverse. The sperm motility, morphology and sperm count, estrus cycle, mating performance, fertility, duration of gestation, corpora lutea count, implantation rate, post-implantation and postnatal loss and litter size were not affected by treatment with the test material at any concentration. There were no test material-related findings in pups noted during the first litter check, the first 4 days post-partum or during the necropsy. Based on the result of the study, the NOAEL (No Observed Adverse Effect Level) for general toxicity was established at a concentration of 10000 ppm and the NOEL (No Observed Effect Level) was established at a concentration of 1000 ppm.The NOAEL and NOEL for reproduction/ developmental toxicity were established at a concentration of 10000 ppm, the highest concentration used in the study (Harlan Laboratories Ltd., 2015c).

The potential for Rosin (Gum Rosin; CAS# 8050-09-7) has been evaluated in a reproductive/developmental toxicity study conducted according to OECD Guideline 422, in which the test material was administered to rats

(12/sex/dose) in dietary mixtures at concentrations of 0, 2500, 5000, and 10000 ppm for a period of 50 days for male rats and to female rats for 14 days prior to pairing, through the pairing and gestation periods until the F1 generation reached day 4 post-partum (at least 36 days, up to 53 days). The NOEL and the NOAEL for developmental toxicity were established at 5000 ppm, based on mortality and body weight effects observed at the 10000 ppm concentration level (Harlan Laboratories Ltd., 2014a).

 

The potential for Rosin, oligomers (CAS# 65997-05-9) has been evaluated in a reproductive/developmental toxicity study conducted according to OECD Guideline 422, in which the test material was administered to rats (12/sex/concentration) in dietary mixtures at concentrations of 0, 3000, 7500 and 15000 ppm. The test material was continuously administered to male rats for 43 days and to female rats for 14 days prior to pairing, through the pairing and gestation periods until the F1 generation reached day 4 post-partum (up to 55 days). The NOEL and the NOAEL for developmental toxicity was determined to be 3000 ppm, based on effects on pup body weight at concentrations of 7500 and 15000 ppm (Harlan Laboratories Ltd., 2014b).

The potential for Gum Rosin (Rosin) to cause developmental toxicity has been evaluated in a reproductive and developmental toxicity screening study conducted according to OECD Guideline 421 in which male and female Sprague Dawley rats were exposed to up to 10000 ppm test substance in the diet during premating, mating, gestation and lactation for a total of 30 exposure days for males and 41-45 exposure days for females study (Inveresk Research, 2003a). At 10000 ppm in the diet, there was a decrease in weight gain or weight loss over the first few weeks of treatment. Decreased weight gain was more severe in females, occurring during the first week on study. After this period, mean weight gain was similar to controls. Pregnant female weight gain was slightly decreased during the first half of gestation. Food consumption was significantly reduced in the 10000 ppm animals for the first 2 weeks of treatment, for both sexes. Food consumption was also slightly reduced throughout gestation and lactation. Consumption at the two lower levels was similar to that of controls. At 10000 ppm, test substance intake in the first week of treatment was lower than the second week for both sexes. There was also a decreased intake in the first week of gestation at this dietary level. For dams, no test material-related effects were noted on mean gestation length or the process of parturition at any exposure concentration. Mean litter and pup weights were slightly reduced for the 10000 ppm dams. There were no obvious external malformations noted in the pups at any of the dose levels in this study. The NOAEL was 3000 ppm, equivalent to a received dose of 288 mg/kg bw/d from GD0 to PND4.

Justification for classification or non-classification

Not classified for reproductive or developmental toxicity according to EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008 or UN Globally Harmonized System of Classification and Labelling of Chemicals (GHS).