Proposed new classification scheme for chemical injury to the human eye.

Purpose: Various ocular alkali burn classification schemes have been published and used to grade human chemical eye injuries for the purpose of identifying treatments and forecasting outcomes. The ILSI chemical eye injury classification scheme was developed for the additional purpose of collecting detailed human eye injury data to provide information on the mechanisms associated with chemical eye injuries. This information will have clinical application, as well as use in the development and validation of new methods to assess ocular toxicity.

Ensuring quality of in vitro alternative test methods: Current practice.

In Vitro toxicology methods are being validated and adopted by regulatory agencies for use as alternatives to animal testing. Such methods may use ex vivo tissues or bioconstructs, some of which may be proprietary. Users of the data from these methods need to be reassured that the assays or assay components used in their studies provide consistent, good quality data over time, matching the standards achieved during the validation process.

Ensuring quality of in vitro alternative test methods: issues and answers.

Many in vitro and ex vivo methods have been developed or are under development to reduce or replace animal usage in toxicity tests. Consistent with the goal of obtaining scientifically sound test data for hazard and risk assessment of chemicals, changes are being made in current policies and procedures to facilitate the acceptance of data developed using these methods. National and international organizations are developing policies and standards for scientific practice to assure quality in implementation of in vitro methods.

Quality assurance for in vitro alternative test methods: quality control issues in test kit production.

In vitro toxicology methods are being adopted by regulatory agencies worldwide. Many of these methods have been validated by using proprietary materials, often in the form of test kits. Guidelines for the use of Good Laboratory Practice methods for in vitro methods have been proposed.

Alternative methods for the median lethal dose (LD(50)) test: the up-and-down procedure for acute oral toxicity.

The authors have developed an improved version of the up-and-down procedure (UDP) as one of the replacements for the traditional acute oral toxicity test formerly used by the Organisation for Economic Co-operation and Development member nations to characterize industrial chemicals, pesticides, and their mixtures. This method improves the performance of acute testing for applications that use the median lethal dose (classic LD50) test while achieving significant reductions in animal use. It uses sequential dosing, together with sophisticated computer-assisted computational methods during the execution and calculation phases of the test.

Tiered testing strategies--acute local toxicity.

More work has been done to develop alternatives to animal use in the areas of eye and skin irritation than in any area other than carcinogenicity. There has long been a belief both in the scientific community and among the public that the development of nonanimal tests in these areas should be simple and straightforward. After more than 20 yr of research, we can identify materials corrosive to the skin without using animals, but the assessment of irritation using in vitro methods alone is still an illusive goal.

Hematology analyzer comparison: Ortho ELT-8/ds vs. Baker 9000 for healthy dogs, mice,and rats.

A Baker 9000 hematology analyzer (electronic impedance) was purchased to replace an Ortho ELT-8/ds analyzer (laser optics) due to discontinued technical support. An analytical comparison of hemograms from healthy dogs, rats, and mice was made from paired disodium ethylenediamine tetra-acetate anticoagulated blood samples. Both instruments were calibrated with human blood products, and the ELT-8/ds hematocrit (HCT) was calibrated to a spun packed cell volume (PCV) for each species.