Assessment of the potential human health risks from exposure to complex substances in accordance with REACH requirements. "White spirit" as a case study.

The European chemical control regulation (REACH) requires that data on physical/chemical, toxicological and environmental hazards be compiled. Additionally, REACH requires formal assessments to ensure that substances can be safely used for their intended purposes. For health hazard assessments, reference values (Derived No Effect levels, DNELs) are calculated from toxicology data and compared to estimated exposure levels. If the ratio of the predicted exposure level to the DNEL, i.e. the Risk Characterization Ratio (RCR), is less than 1, the risk is considered controlled; otherwise, additional Risk Management Measures (RMM) must be applied. These requirements pose particular challenges for complex substances. Herein, "white spirit", a complex hydrocarbon solvent, is used as an example to illustrate how these procedures were applied. Hydrocarbon solvents were divided into categories of similar substances. Representative substances were identified for DNEL determinations. Adjustment factors were applied to the no effect levels to calculate the DNELs. Exposure assessments utilized a standardized set of generic exposure scenarios (GES) which incorporated exposure predictions for solvent handling activities. Computer-based tools were developed to automate RCR calculations and identify appropriate RMMs, allowing consistent communications to users via safety data sheets.

Gasoline toxicology: overview of regulatory and product stewardship programs.

Significant efforts have been made to characterize the toxicological properties of gasoline. There have been both mandatory and voluntary toxicology testing programs to generate hazard characterization data for gasoline, the refinery process streams used to blend gasoline, and individual chemical constituents found in gasoline. The Clean Air Act (CAA) (Clean Air Act, 2012: § 7401, et seq.) is the primary tool for the U.S. Environmental Protection Agency (EPA) to regulate gasoline and this supplement presents the results of the Section 211(b) Alternative Tier 2 studies required for CAA Fuel and Fuel Additive registration. Gasoline blending streams have also been evaluated by EPA under the voluntary High Production Volume (HPV) Challenge Program through which the petroleum industry provide data on over 80 refinery streams used in gasoline. Product stewardship efforts by companies and associations such as the American Petroleum Institute (API), Conservation of Clean Air and Water Europe (CONCAWE), and the Petroleum Product Stewardship Council (PPSC) have contributed a significant amount of hazard characterization data on gasoline and related substances. The hazard of gasoline and anticipated exposure to gasoline vapor has been well characterized for risk assessment purposes.