The evaluation and hazard classification of toxicological information for workplace hazardous materials information system material safety data sheets

Toxicity Assessment of Industrial Chemicals and Airborne Contaminants: Transition fromIn VivotoIn VitroTest Methods: A Review

Exposure to occupational and environmental contaminants is a major contributor to human health problems. Inhalation of gases, vapors, aerosols, and mixtures of these can cause a wide range of adverse health effects, ranging from simple irritation to systemic diseases. Despite significant achievements in the risk assessment of chemicals, the toxicological database, particularly for industrial chemicals, remains limited. Considering there are approximately 80,000 chemicals in commerce, and an extremely large number of chemical mixtures, in vivo testing of this large number is unachievable from both economical and practical perspectives. While in vitro methods are capable of rapidly providing toxicity information, regulatory agencies in general are still cautious about the replacement of whole-animal methods with new in vitro techniques. Although studying the toxic effects of inhaled chemicals is a complex subject, recent studies demonstrate that in vitro methods may have significant potential for assessing the toxicity of airborne contaminants. In this review, current toxicity test methods for risk evaluation of industrial chemicals and airborne contaminants are presented. To evaluate the potential applications of in vitro methods for studying respiratory toxicity, more recent models developed for toxicity testing of airborne contaminants are discussed.

The role of professional judgment in chemical hazard assessment and communication

Most hazard assessment guidelines and regulatory requirements--both nationally and internationally--explicitly advocate the use of professional judgment in hazard assessment. However, the practical application of such judgment (i.e., how and when that judgment should be applied) is often left to the assessor's discretion. This can lead to inconsistent guidance on the use, handling, and disposal of chemicals and can ultimately result in ineffective hazard communication and chemical management. This paper traces the regulatory rationale and legislative conventions for applying professional judgment in hazard assessment to key global regulations and professional standards. A series of guidelines for applying professional judgment are drawn from these regulations and standards, consistent with sound toxicological concepts and principles. The guidelines are illustrated by cogent examples drawn from the experiences of professional toxicologists and industrial hygienists charged with complying with the norms of hazard assessment. We contend that these guidelines and supporting examples are fully compliant with international regulations, decision-neutral with regard to the stringency of the assessment, and reflective of the harmonized efforts to develop more effective and complete hazard communications. We discuss the regulatory ramifications and needs for better definition of professional judgment in hazard assessments under GHS and REACH.

Material safety data sheets: are they reliable in identifying human hazards?

The material safety data sheet (MSDS) is an integral part of a worker's evaluation for suspected occupational asthma and dermatitis. However, established US federal guidelines for creating an MSDS do not require that certain key information relevant to the diagnosis of these disorders be included. This rostrum is intended to highlight the limitations of MSDSs as they pertain to the diagnosis of occupational asthma and occupational dermatitis so that future consideration can be given to modification of the existing MSDS guidelines. This article summarizes the origins of MSDS documents, provides an overview of their format, and discusses some of their inherent limitations, which at times impede proper medical evaluation by physicians and other health care professionals. MSDSs are an essential part of making the workplace a safer environment. More complete disclosure about both irritation and sensitization risks in these documents would facilitate the evaluation of workers for OA and OD. Their current ambiguity often delays the diagnosis of these occupational diseases and places the worker at further risk for development of occupational-related long-term disorders. Health care professionals have an obligation to better educate themselves regarding the interpretation of MSDSs and to recognize that they sometimes provide incomplete data.