4,4'-isopropylidenediphenol

Endpoint summary

Additional information

There are a number of guideline and non-guideline studies available that have been performed with Bisphenol A.

Toxicity to soil macroorganisms

Two guideline terrestrial invertebrate studies have been performed, one with the potworm, Enchytraeus crypticus, (Moser and Egeler, 2007a; Staples et al., 2010) and one with the collembolan, Folsomia candida (Moser and Egeler, 2007b; Staples et al., 2010). A discrepancy in the findings from a short and long-term earthworm study (Johnson et al., 2005a; Johnson et al., 2005) where there was no effect in the chronic study at doses that caused mortality in the acute study prompted the conduct of a new, fully valid chronic study with the potworm Enchytraeus crypticus (Moser and Egeler, 2007a; Staples et al., 2010). No effects on mortality or number of juveniles were observed at the highest dose tested of 100 mg/kg dw. This is in agreement with the findings from the earthworm chronic (Johnson et al., 2005) where the NOEC of 100 mg/kg was also established. No effect on survival during the chronic 28-day test with the collembolan, Folsomia candida, exposed to Bisphenol A in artificial soil was observed. The number of juveniles was reduced at the highest dose tested, 1000 mg/kg dw, compared to controls so the NOEC established in the study was 500 mg/kg dw.

Toxicity to terrestrial plants

An OECD Guideline 208 study assessing emergence and growth in 6 different species of terrestrial plant exposed to Bisphenol A was performed (Hoberg, 2007; Staples et al., 2010). The plant species tested were three monocotyledons, corn (Zea mays), oats (Avena sativa) and wheat (Triticum aestivum), and three dicotyledons, cabbage (Brassica oleracea), soybean (Glycine max) and tomato (Lycopersicon esculentum). For the endpoint of percent emergence, there were no effects at the highest dose tested with oat, soybean, corn, and wheat. Tomato and cabbage were equally sensitive for the endpoint percent emergence with an LOEC of 320 mg/kg and a NOEC of 130 mg/kg. There were effects on dry shoot weight endpoint, an assessment of growth, in all species tested. The most sensitive species was tomato with a LOEC and a NOEC of 50 and 20 mg/kg, respectively.

Toxicity to birds

Although no guideline avian reproduction studies are available, there are a number of egg injections studies which provide a weight of evidence, worst-case type of exposure which mimics maternal transfer of material to embryos. Endpoints assessed included egg laying, embryonic development, phenotypic and genotypic chick sex ratios, sexual behaviour, and hatchability. Conclusions from the two weight of evidence and one supporting study were in agreement that the risk for adverse reproductive toxicity in avian wildlife resulting from embryonic exposure is probably low. Given the low potential for dietary exposure of avian populations to Bisphenol A, a full avian reproduction study with the sacrifice of many animals, is not justified. This is confirmed by the 2008 Addendum to the EU Risk Assessment that concluded that it is not considered appropriate to request a multi-generational study with birds because Bisphenol A is readily biodegradable and has a low bioaccumulation potential, the existing studies addressed several relevant end points, and the PEC/PNEC ratios are all significantly below 1.

Environmental concentrations in the terrestrial environment are expected to be low, thus exposure to terrestrial organisms is expected to be limited. Effects to soil invertebrates and plants are well characterised and potential adverse effects in birds are not predicted from results from studies with in ovo exposure to chickens and quail.