Is 2% hydroxypropylmethylcellulose a safe solution for intraoperative clinical applications?

We examined 2% hydroxypropylmethylcellulose prepared for clinical intraocular surgical procedures in various laboratories. Each sample contained a variety of particulate debris of botanical origin, although in varying amounts. The identified material was also seen in a sample of the raw material from which all the clinical material had been prepared. Our conclusion is that filtration methods, which are the physical methods used to purify the product, are at worst ineffective and at best inadequate. Until proper laboratory and clinical studies confirm an acceptable level of adverse reactions, we recommend that this material not be used clinically.