2,6-bis({[bis(2-hydroxyethyl)amino]methyl})-4-[2-(3-{[bis(2-hydroxyethyl)amino]methyl}-4-hydroxyphenyl)propan-2-yl]phenol; 2,6-bis({[bis(2-hydroxyethyl)amino]methyl})-4-[2-(4-hydroxyphenyl)propan-2-yl]phenol; 2-[(2-hydroxyethyl)amino]ethan-1-ol; 2-{[bis(2-hydroxyethyl)amino]methyl}-4-[2-(3-{[bis(2-hydroxyethyl)amino]methyl}-4-hydroxyphenyl)propan-2-yl]phenol; 2-{[bis(2-hydroxyethyl)amino]methyl}-4-[2-(4-hydroxyphenyl)propan-2-yl]phenol; 4-[2-(4-hydroxyphenyl)propan-2-yl]phenol

Endpoint summary

Key value for chemical safety assessment

Effects on fertility

Effect on fertility: via oral route

Endpoint conclusion:

adverse effect observed

Dose descriptor:

NOAEL

50 mg/kg bw/day

Study duration:

subchronic

Species:

rat

Effect on fertility: via inhalation route

Endpoint conclusion:

no study available

Effect on fertility: via dermal route

Endpoint conclusion:

no study available

Additional information

The substance contains approx. 15 % of 2,2-bis(4-hydroxyphenyl)propane (BPA; CAS No 80-05-7) as constituent, which is legally classified as reproductive toxicant Cat. 1B. According to Regulation (EU) 1272/2008 a mixture has to be classified as reproductive toxicant, if at least one ingredient is classified as a Cat. 1A, Cat. 1B or Cat. 2 reproductive toxicant and is present at or above the appropriate generic concentration limit for the respective category. This concentration limit is >/= 3.0 % for Cat. 2 and >/= 0.3 % for Cat. 1A or 1B (cp. Reg. (EU) 1272/2008, table 3.7.2). Consequently, for the substance containing 15 % BPA a classification for reproductive toxicity Cat. 1B is warranted.

Additionally, assessment of reproductive toxicity based on read across to BPA is possible. Another main constituent of the substance is 2,2'-iminodiethanol (DEA; CAS No 111-42-2) contained in the substance at approx. 40 %. Two reaction products of DEA, formaldehyde and BPA (i.e. Mannich Bases) account for further 39 % of the substance (Mannich Base 1 ca. 26 %, Mannich Base 2 [two isomers) ca. 13 %). The Mannich Bases are structurally similar to BPA, but are larger molecules (i.e. BPA with one or two diethylaminomethyl-substituents attached to the aromatic ring). A QSAR analysis (OECD toolbox, version 3.3.0.132) revealed for the Mannich Bases no specific finding except a predicted estrogen receptor binding based on the BPA core-structure. Therefore, based on the available evidence it is not expected that the Mannich Bases determine the overall toxicological picture of the substance and the toxicological properties of the two main constituents DEA and BPA instead are decisive for the toxicological profile of the substance. In conclusion, reproductive toxicity of the substance can be assessed based on read across to BPA and DEA.

 

For BPA summaries of toxicity to reproduction exist based on peer-reviewed chemical risk assessments, e.g. EU Risk Assessment Reports, SCOEL Recommendation and EFSA Opinion. These are taken into account in the following:

The EU RAR 2003 concluded: "No human data on reproductive toxicity of BPA are available. BPA has been shown to have endocrine modulating activity in a number of screening assays, with a potency that generally ranged from 3 to 5 orders of magnitude less than that of oestradiol. The effects of BPA on fertility and reproductive performance have been investigated in two-generation and multi-generation studies in the rat and a continuous breeding study in mice. Effects were seen in both species at approximately the same dose level and it is considered that the NOAEL of 50 mg/kg/day identified in the rat multi-generation study is also likely to produce no adverse effects in mice for which there is only a LOAEL of 300 mg/kg/day for a small decrease in epididymal weight in F1 males. The NOAEL of 50 mg/kg/day from the multi-generation study will be used for risk characterisation purposes, in relation to effects on fertility."

The 2008 updated EU RAR concluded: "A new two-generation study in mice by Tyl et al. (published in 2008) provides a comprehensive and definitive investigation on the effects of BPA on reproduction at exposure levels spanning the low (ug/kg/day) to high (mg/kg/day) ranges. This study showed that BPA causes adverse effects on pregnancy and the offspring at 600 mg/kg/day, an exposure level that also caused mild parental toxicity. Fertility was not affected by BPA exposure. A NOAEL for reproductive toxicity of 50 mg/kd/day was identified and should be used in the risk assessment."

SCOEL 2014 concluded concerning potential low-dose effects: "Even though there are some concerns related to the long-term effects of BPA at exposure levels lower than 5 mg/kg bw after exposure during the foetal and early postnatal period, the results of these studies are controversial and there is no clear support for these effects at low dose levels from good quality animal studies (including the recent study by Delcloset al2014). Therefore, at present SCOEL did not consider them relevant for deriving the recommended OEL."

SCOEL 2014 concluded on reproductive and developmental toxicity: "Overall, in standard reproductive and developmental studies in rodents, effects on reproduction have been seen only at high doses showing also other toxic effects. Even though several non-guideline studies suggest effects on reproductive and developmental parameters at lower dose levels (< 5 mg/kg bw), the data are contradictory and are not supported by the recent FDA/NTCR study with a wide-dose range (Delclos et al 2014). In humans, based on Chinese epidemiological studies, there is some concern for impaired sperm quality but, for example, the effect of other concurrent exposures cannot be excluded. In addition, there are some concerns on the potential developmental neurotoxicity of BPA based on animal studies suggesting effects on memory and learning and anxiety-like behaviour. However, since the data are very inconsistent it is difficult to conclude on the relevance of these findings."

EFSA Opinion 2015 concluded concerning potential Non-Monotonic-Dose-Responses (NMDR): "The CEF Panel developed criteria for nonmonotonic dose-responses (NMDRs) and reviewed studies reporting a NMDR for BPA. None of the studies fulfil these criteria. Overall the CEF Panel concluded that the available data do not provide evidence that BPA exhibits a NMDR for the endpoints considered (reproductive/developmental toxicity, neurotoxicity/behavioural effects, metabolic effects, proliferative changes in mammary gland)."

EFSA Opinion 2015 concluded on reproductive and developmental toxicity: "Overall, the better powered, better conducted studies in animals found few consistent effects of in-utero exposure to BPA on reproductive development at dose levels at or below 3.6 mg BPA/kg/day HED. On balance, the evidence remains contradictory and highly variable between studies. The CEF Panel noted that there is some evidence for effects of BPA exposure on several parameters indicative for changes in the reproductive system in adult male animals at dose levels below 3.6 mg/kg bw per day, although these effects were modest. It is not possible to conclude that these changes are reflective of changes in reproductive performance, since the studies rarely included a forced/continuous breeding phase in adulthood to establish reduced fertility. However, in several multigenerational studies no effects were observed at dose levels as low as 3 mg/kg bw per day up to at least 50 mg/kg bw per day.

Using a WoE approach, the CEF Panel assigned a likelihood level of “as likely as not” to reproductive and developmental effects of BPA at low doses (below the HED of 3.6 mg/kg bw per day). Since the likelihood level for this endpoint is less than "likely" (.....), this endpoint was not taken forward for assessing the toxicological reference point, but was taken into account in the evaluation of uncertainty for hazard characterisation and risk characterisation (.....)."

 

With respect to DEA no study on toxicity to reproduction is available. Such a study (EOGRTS, OECD 443) is requested according to a recent ECHA draft decision (ECHA decision on substance evaluation pursuant to article 46(1) of Regulation (EC) No 1907/2006 for 2,2'-iminodiethanol - CAS No 111-42-2 (EC No 203 -868 -0; http://echa.europa.eu/documents/10162/d34b5848-6b8e-4944-8ce7-4d0200ea43d7).

Justification for selection of Effect on fertility via oral route:
Based on read-across (in this case BPA; CAS No 80-05-7) a fully reliable three-generation reproductive study on rats is selected.

Effects on developmental toxicity

Effect on developmental toxicity: via oral route

Endpoint conclusion:

adverse effect observed

Dose descriptor:

NOAEL

50 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

For an assessment of developmental toxicity read across to the two main ingredients of the substance 2,2'-iminodiethanol (DEA; CAS No 111 -42 -2) and 2,2-bis(4-hydroxyphenyl)propane (BPA; CAS No 80 -05 -7) is performed. These account for approx. 55 % of the substance (BPA ca. 15 %, DEA ca. 40 %), and information on their developmental toxicity is thus relevant for the assessment of the substance. Two reaction products (Mannich Bases) of DEA, formaldehyde and BPA account for further 39 % of the substance (Mannich Base 1 ca. 26 %, Mannich Base 2 [two isomers] ca. 13 %). The Mannich Bases are structurally similar to BPA, but are larger molecules (i.e. BPA with one or two diethanolaminomethyl-substituents attached to the aromatic ring). A QSAR analysis (OECD toolbox, version 3.3.0.132) revealed for the Mannich Bases no specific finding except a predicted estrogen receptor binding based on the BPA core-structure. Therefore, based on the available evidence it is not expected that the Mannich Bases determine the overall toxicological picture of the substance and the toxicological properties of the main ingredients DEA and BPA instead are decisive for the toxicological profile of the substance.

In conclusion, developmental toxicity of the substance can be sufficiently assessed by the available comprehensive data for BPA and DEA. The so concluded overall relevant lowest threshold and the most critical classification will be the basis for the protective measures for the registered substance and therefore is based on worst case assessment, since for the overall assessment in case of differences the lower respective NOAEL/LOAEL from the two constituents is used.

 

For BPA and DEA summaries on developmental toxicity exist based on peer-reviewed chemical risk assessments, e.g. EU Risk Assessment Report and OECD SIDS Initial Assessment Report, respectively. These are taken into account in the following.

 

Concerning BPA the 2003 EU RAR concluded: No human data on reproductive toxicity of Bisphenol A are available. Bisphenol A has been shown to have endocrine modulating activity in a number of screening assays, whith a potency that generally ranged from 3 to 5 orders of magnitude less than that of oestradiol. The effects of Bisphenol A on fertility and reproductive performance have been investigated in two-generation and multi-generation studies in the rat and a continuous breeding study in mice. Effects were seen in both species at approximately the same dose level and it is considered that the NOAEL of 50 mg/kg/day identified in the rat multi-generation study is also likely to produce no adverse effects in mice for which there is only a LOAEL of 300 mg/kg/day for a small decrease in epididymal weight in F1 males. The NOAEL of 50 mg/kg/day from the multi-generation study will be used for risk characterisation purposes, in relation to effects on fertility.

The 2008 updated EU RAR concluded: A new two-generation study in mice by Tyl et al. (published in 2008) provides a comprehensive and definitive investigation on the effects of Bispheol A on reproduction at exposure levels spanning the low (ug/kg/day) to high (mg/kg/day) ranges. This study showed that Bisphenol A causes adverse effects on pregnancy and the offspring at 600 mg/kg/day, an exposure level that also caused mild parental toxicity. Fertility was not affected by Bisphenol A exposure. A NOAEL for reproductive toxicity of 50 mg/kd/day was identified and should be used in the risk assessment.

SCOEL 2014 concluded concerning potential low-dose effects: "Even though there are some concerns related to the long-term effects of BPA at exposure levels lower than 5 mg/kg bw after exposure during the foetal and early postnatal period, the results of these studies are controversial and there is no clear support for these effects at low dose levels from good quality animal studies (including the recent study by Delcloset al2014). Therefore, at present SCOEL did not consider them relevant for deriving the recommended OEL."

SCOEL 2014 concluded on reproductive and developmental toxicity: "Overall, in standard reproductive and developmental studies in rodents, effects on reproduction have been seen only at high doses showing also other toxic effects. Even though several non-guideline studies suggest effects on reproductive and developmental parameters at lower dose levels (< 5 mg/kg bw), the data are contradictory and are not supported by the recent FDA/NTCR study with a wide-dose range (Delclos et al 2014). In humans, based on Chinese epidemiological studies, there is some concern for impaired sperm quality but, for example, the effect of other concurrent exposures cannot be excluded. In addition, there are some concerns on the potential developmental neurotoxicity of BPA based on animal studies suggesting effects on memory and learning and anxiety-like behaviour. However, since the data are very inconsistent it is difficult to conclude on the relevance of these findings."

EFSA 2015 concluded concerning potential Non-Monotonic-Dose-Responses (NMDR): "The CEF Panel developed criteria for nonmonotonic dose-responses (NMDRs) and reviewed studies reporting a NMDR for BPA. None of the studies fulfil these criteria. Overall the CEF Panel concluded that the available data do not provide evidence that BPA exhibits a NMDR for the endpoints considered (reproductive/developmental toxicity, neurotoxicity/behavioural effects, metabolic effects, proliferative changes in mammary gland)."

EFSA 2015 concluded on reproductive and developmental toxicity: "Overall, the better powered, better conducted studies in animals found few consistent effects of in-utero exposure to BPA on reproductive development at dose levels at or below 3.6 mg BPA/kg/day HED. On balance, the evidence remains contradictory and highly variable between studies. The CEF Panel noted that there is some evidence for effects of BPA exposure on several parameters indicative for changes in the reproductive system in adult male animals at dose levels below 3.6 mg/kg bw per day, although these effects were modest. It is not possible to conclude that these changes are reflective of changes in reproductive performance, since the studies rarely included a forced/continuous breeding phase in adulthood to establish reduced fertility. However, in several multigenerational studies no effects were observed at dose levels as low as 3 mg/kg bw per day up to at least 50 mg/kg bw per day.

Using a WoE approach, the CEF Panel assigned a likelihood level of “as likely as not” to reproductive and developmental effects of BPA at low doses (below the HED of 3.6 mg/kg bw per day). Since the likelihood level for this endpoint is less than "likely" (....), this endpoint was not taken forward for assessing the toxicological reference point, but was taken into account in the evaluation of uncertainty for hazard characterisation and risk characterisation (....)."

 

Developmental toxicity of the second ingredient DEA is summarized in OECD SIDS, 2007/last updated in 2008:

"DEA exposure to an aerosol in a nose-only exposure system led to maternal toxicity at the highest concentration (0.2 mg/l) and induced at this dose level signs of embryo- or fetotoxicity in the form of an increased number of foetuses with skeletal variations. Malformations were not observed. The NOAEC for maternal and prenatal developmental toxicity was 0.05 mg/l.

Prenatal developmental toxicity of DEA following dermal application was investigated in rats and rabbits. In rats, maternal toxicity was substantiated by moderate to severe skin irritation, reduced maternal body weight gain, increased kidney weights and haematological effects including anaemia, abnormal red cell morphology and decreased platelet count. In the foetuses, increased incidences of skeletal variations were observed. The LOAEL for maternal toxicity was 150 mg/kg bw, while the NOAEL for prenatal developmental toxicity was 380 mg/kg bw. The NOAEL for teratogenicity was 1500 mg/kg bw. In rabbits, doses displayed marked skin irritation, reduced body weight gain and food consumption and discoloured kidneys. The NOAEL for maternal toxicity was 35 mg/kg bw, the NOAEL for prenatal developmental toxicity including teratogenicity was 350 mg/kg bw, the highest dose tested.

Orally applied DEA within a developmental toxicity study in rats caused maternal toxicity in the form of increased mortality at high dose levels. Reduced body weight/body weight gain and food consumption and increased kidney weight were observed. Developmental toxicity consisted of an increase in postimplantation mortality and early postnatal mortality as well as reduced pup body weight. The NOAEL for maternal and postnatal developmental toxicity was 50 mg/kg bw. Thus, pre- and postnatal developmental toxicity was only observed in the presence of clear maternal toxicity and at dose levels considered as high."

 

Overall, no indications for teratogenicity is revealed from neither of the data of BPA or DEA. Developmental toxicity occurs only in the presence of maternal toxicity, thus protection of maternal toxicity does prevent developmental toxicity. The lowest NOAEL of 50 mg/kg for developmental toxicity after exposure to DEA is taken forward for risk assessment.

Justification for selection of Effect on developmental toxicity: via oral route:
The study with the lowest NOAEL for effects on developmental toxicity (in this case for the read across substance DEA; CAS No 111-42-2) is selected.

Justification for classification or non-classification

According to Regulation (EC) No 1272/2008, Annex I, classification is warranted as Repr. Tox. Cat. 1B (H360F).