Benzene toxicity: studying a subject to death

Violence and the Chemicals Industry: Reframing Regulatory Obstructionism

When government actors seek to restrict the sale of hazardous substances, industry actors tend to intervene, deploying coordinated strategies aimed at delaying, preventing or weakening attempts to regulate their products. In many cases, this has involved deliberate efforts to obfuscate science, mislead the public and manipulate political actors in order to ensure desired policy outcomes. Strategies of regulatory obstructionism have resulted in the prolonged dispersal of harmful chemical substances with tangible impacts on public health. This article proposes that this behavior should be interpreted as a form of violence. Examining the regulatory histories of lead, benzene, asbestos and PCBs, the article demonstrates how regulatory obstructionism and violence have become intractable characteristics of the chemical industry.

Pharmacokinetically based risk assessment of workplace exposure to benzene

Cancer risk from exposure to benzene for a working lifetime was estimated from data obtained in studies with rodents. Cancers of the Zymbal gland and the blood-forming system were selected as endpoints for the assessment because of their consistent occurrence. The combined metabolites were judged from toxicological data to be the best representative of the reactive agent. Because of similarity in the percentages of lifetime exposed in the rodent studies and in the occupational setting, the amount metabolized/day as a result of exposures 5 days a week for a lifetime was judged to be an appropriate dose paradigm for this assessment. Derived Michaelis-Menton constants were used to convert the doses of combined metabolites from the pharmacokinetic studies to the doses used in the bioassays. Scaling across species was based on allometric relationships. Experimental data were used to scale doses across species with body weight ratios raised to the exponents of 0.74 for the inhalation route and 1.0 for the oral route. The occupational lifetime cancer risk estimated from rodent data was 6 to 14 cases/1000 workers, which is consistent with the 9.5 to 174 leukemia cases/1000 estimated by others from epidemiological data. Implications of these estimates and uncertainties associated with making them are discussed.

Living in a chemical world: actions and reactions to industrial carcinogens

The synthesis of chemical substances has resulted in technological benefits for society and has also caused increased chemical exposures and risks of related cancers. Although progress has been made in cancer treatment, there has been little improvement in real survival time for people who develop the major forms. Therefore, the need to prevent cancer is paramount. The greatest chemical exposures and risk of associated preventable cancers are found in the workplace, but generally environmental exposures receive greater public attention. Chemical causes of cancer have been identified, and in some cases decades have passed before controls have been adequately instituted. Some companies show a high regard for worker health, while others may minimize or misrepresent the hazards to exposed workers. Medical personnel receive relatively little education in the recognition of industrially related diseases. Workers are often unaware of their risks or are trapped in jobs because of economic necessity, and government has been slow to regulate, in part because of lobbying efforts. Experience has shown that when chemicals are regulated relatively soon after they are identified as hazardous, lives are saved, and the industry is economically healthy; however, when regulation is delayed, thousands of people die unnecessarily, and the cost to industry and society are phenomenal. Society has the opportunity to apply the knowledge learned from these experiences as we address current problems of chemical pollution.