Environmental toxicity study of poly(2-oxazoline)s

Poly(2-oxazoline)s (POx) are a promising class of synthetic polymers suitable for biomedical applications; hence, there is a possibility that POx may occur through the food chain in wastewaters and subsequently in farmlands. Therefore, it is important to investigate their possible environmental toxicity. Homopolymer poly(2-ethyl-2-oxazoline) (PEtOx) and statistical copolymer poly[(2-ethyl-2-oxazoline)-stat-(2-(3-butenyl)-2-oxazoline)] (coPOx), both with theoretical chain length 100 and 200 monomer units, have been tested according to OECD Guideline 208 and 209. Significant growth inhibition of Sinapis Alba after 3 day exposure has been determined in the case of coPOx100. Moreover, statistically significant stimulation effect of growth in the case of PEtOx100 has been observed. Respirometric assay clearly confirmed that aerobic degradation of all studied POx by activated sludge is impossible. Biosorption tests on dead activated sludge have shown that almost all added POx (up to 95%) in concentration 500 mg L-1 are adsorbed on activated sludge.