1,1'-methylenebis(4-isocyanatobenzene) and its oligomeric reaction products with butane-1,3-diol, 2,2'-oxydiethanol and propane-1,2-diol

Toxicity to aquatic plants other than algae

Description of key information

Not required by REACH annexes. However, a mesocosm study (Heimbach, 1993) with pMDI exists in which the toxicity towards macrophytes (Potamogeton crispus and Zannichellia palustris) was assessed. No toxicity was observed at a loading of 1000 and 10,000 mg/L. The absence of any adverse finding in the 112-day mesocosm study on pMDI strongly supports that there is no long-term aquatic hazard to be expected from the substances of the MDI category.

Additional information

In a mesocosm study (Heimbach, 1993), a pond was exposed to a loading of 1000 and 10,000 mg/L of pMDI during 112 days. Three 4.5 m³ ponds were filled with groundwater and added natural lake sediment (15 cm). The systems were left outdoors for six months. Links between ponds were then closed; fish were added to ponds (in cages) and substance added to two ponds at two different loadings (1000 and 10,000 mg/L). The third pond was the control. The substance was added directly onto the bottom of the ponds with a hose. The toxicity effects were assessed to two macrophytes, Potamogeton crispus and Zannichellia palustris. No effects were seen at both loadings. The MDI applied polymerized and formed a stable layer on the sediment surface of the ponds. At the end of the study, approximately 100% of the substance was found in the sediment as hardened material.