Health effects classification and its role in the derivation of minimal risk levels: Renal effects

Action levels for airborne uranium in the workplace: chemical and radiological assessments

A method is described for deriving two levels of action-an investigation level (IL) and an immediate action level (IAL)-for different forms and mixtures of the natural uranium (U) isotopes ²³⁴U, ²³⁵U, and ²³⁸U in air in the workplace. An IL indicates the need to confirm the validity of moderately elevated measurements of airborne U and adequacy of confinement controls and determine whether work limitations are appropriate. An IAL indicates that safeguards should be put into place immediately, including removal of workers from further exposure until conditions are acceptable. Derivations of ILs and IALs are based on latest radiation protection guidance, information on chemical toxicity of U, and biokinetic models for U. An action level (IL or IAL) is the more restrictive of two derived values, the action level based on U as a chemical hazard and the action level based on U as a radiation hazard.

Health effects classification and its role in the derivation of minimal risk levels: Immunological effects

The Agency for Toxic Substances and Disease Registry (ATSDR) derives health-based guidance values known as minimal risk levels (MRLs). By definition, an MRL is a substance-specific estimate of the daily human exposure to a substance that is likely to be without an appreciable risk of adverse, noncancer effects over a specified duration of exposure. MRLs are preferentially derived from human studies, if available, or from the most sensitive animal species and the endpoint that is most relevant for humans. To date, the agency has derived 346 MRLs. Fifteen MRLs were derived for 11 different chemicals where the database has identified the immune system as the most sensitive target of toxicity. The chemicals include benzene, chlorfenvinphos, endosulfan, heptachlor, gamma-hexachlorocyclohexane, dibutyl tin, tributyl tin, PCBs, 2,3,4,7,8-pentachlorodibenzofuran, 2,3,7,8-tetrachlorodibenzo-p-dioxin, and 2,4-dichlorophenol. The agency's rationale for classification of immunological endpoints is discussed and a brief description given of the critical studies selected for MRL development using immune system endpoints.

Motivation of chemical industry social responsibility through Responsible Care

Advocates of corporate social responsibility argue corporations should not only meet the needs of shareholders, but other key stakeholders including the community, customers, suppliers, and employees. Since 1988, the chemical industry has engaged in a major self-regulatory "Responsible Care" industry-wide social responsibility campaign to ensure environmental, public health, safety, and security performance among member companies. Contrary to the arguments of advocates of corporate social responsibility that such efforts meet the needs of stakeholders other than shareholders such as the community, the primary goal of the Responsible Care effort has been to change public concerns and opinion about chemical industry environmental and public health practices while also opposing support for stronger and more expensive public health and environmental legislation and regulation of chemical products, even if warranted.