Occupational Cancer
Peter G. Shields in Cancer Risk Assessment, 2005
Currently, the process of identifying substances and occupations associated with cancer is performed by a variety of state, national, and international organizations. The International Agency for Research on Cancer (IARC), the National Institute for Occupational Safety and Health, the U.S. Public Health Services’ National Toxicology Program (NTP), the Environmental Protection Agency (EPA), the American Conference of Governmental Industrial Hygienists (ACGIH), and OSHA are noteworthy examples. These organizations establish lists of hazards and occupations with carcinogenic potential. Hazard identification tends to be based on assessments of epidemiological and clinical reports, as well as animal research and in vitro studies. Each agency classifies carcinogens differently, with criteria varying considerably. Some organizations simply identify a hazard, whereas others propose or require occupational exposure limits. Such variability underscores the complexity of occupational risk assessment. Case reports, epidemiology, and animal investigations form the basis of scientific information used to identify occupational carcinogens. Their scope, benefits, and limitations in the occupational setting are described below.
Techniques for Assessing the Health Risks of Dermal Contact with Chemicals in the Environment
Rhoda G. M. Wang, James B. Knaak, Howard I. Maibach in Health Risk Assessment, 2017
Besides inhalation, skin contact is an important portal of entry for many industrial chemicals used in the workplace. Almost all occupational exposure limits (OELs), such as the Threshold Limit Values (TLVs) of the American Conference of Governmental Industrial Hygienists (ACGIH) and the Permissible Exposure Limits of the United States Occupational Safety and Health Administration (OSHA), are criteria for defining acceptable levels of inhalation exposure. For certain chemicals which are judged to have a significant potential to be absorbed from skin contact, a skin notation is appended to the OEL. The ACGIH (1990) defines the skin notation as follows:
Answers
Ken Addley in MCQs, MEQs and OSPEs in Occupational Medicine, 2023
The requirement for health surveillance is dependent on the level of residual risk. It is not always required when there is exposure to asthma-causing agents if there is no residual risk after the control measures are in place. Health surveillance may be required even when exposures are below the occupational exposure limits. It differs from medical screening which is typically related to health promotion and generally does not distinguish between the health effects of exposure and those from pre-existing conditions.
Application of adverse outcome pathway networks to integrate mechanistic data informing the choice of a point of departure for hydrogen sulfide exposure limits
Published in Critical Reviews in Toxicology, 2021
Katy O. Goyak, R. Jeffrey Lewis
One step in the development of occupational exposure limits is the selection of the critical effect, or point of departure, associated with exposure to a chemical. This choice can vary across organizations and may reflect both problem formulation (e.g. is the exposure limit relevant for intermittent use or continuous use over an 8-h work day) and risk policy (e.g. is higher weight placed on animal studies with controlled experimental conditions or human experience) (Deveau et al. 2015). In practice, this can lead different organizations to select distinct outcomes, as is the case with H2S, partially contributing to a range of global exposure limits for H2S (0.001–10 ppm) (as depicted and referenced in Figure 1). To move toward harmonization, new evidence integration methods provide a means to incorporate mechanistic information into the selection of a point of departure and increase confidence in this selection via added biological context. To this end, an adverse outcome pathway approach was applied to integrate mechanistic information, demonstrating consistency in both response across experimental conditions and quantitative effect levels across related biological events.
Biological monitoring of exposure to low concentrations of benzene in workers at a metallurgical coke production plant: new insights into S-phenylmercapturic acid and urinary benzene
Published in Biomarkers, 2018
Piero Lovreglio, Giuseppe De Palma, Anna Barbieri, Roberta Andreoli, Ignazio Drago, Luciano Greco, Elisabetta Gallo, Laura Diomede, Pietro Scaramuzzo, Maria Cristina Ricossa, Jacopo Fostinelli, Pietro Apostoli, Leonardo Soleo
Occupational exposure to benzene can still occur in western nations among workers in oil refineries, coke production plants, during fuel transport and distribution and in the chemical industry, where benzene is the raw material or an intermediate product (ATSDR 2007). Such benzene concentrations are generally within the threshold limit value - time weighted average (TLV-TWA®) of 1600 µg/m3 established by the American Conference Governmental Industrial Hygienists (ACGIH 2016). But benzene is also present in living environments, largely deriving from vehicles exhaust fumes and cigarette smoking (Duarte-Davidson et al.2001). In exposed subjects, benzene can provoke acute myeloid leukaemia/acute non-lymphocytic leukaemia, and for this reason the International Agency for Research on Cancer (IARC) has included it among group 1 compounds, that are carcinogenic to humans (IARC 2012). At present, the Scientific Committee on Occupational Exposure Limits classifies it among genotoxic carcinogenic agents for which the existence of a threshold cannot be sufficiently supported, so that even low exposures are considered to pose a significant risk (Bolt and Huici-Montagud 2008).
Metal emissions from e-cigarettes: a risk assessment analysis of a recently-published study
Published in Inhalation Toxicology, 2018
Konstantinos E. Farsalinos, Brad Rodu
PDE levels for inhalational medications were the primary measure used in this risk assessment analysis. The basis behind this rationale is that, similarly to medications which are prescribed based on a risk-benefit analysis for patients with relevant disease, the exposure from ECs should be interpreted in the context of potential benefits for smokers who use ECs to reduce or quit smoking. Moreover, the standards for pharmaceutical products are quite high and stringent. Thus, although they may not represent absolute safety, they should be considered appropriate for a product such as ECs. MRLs were considered the second best option, since they apply to the general population and consider a 24-h exposure. RELs are occupational setting safety limits. The approach of using the latter has been criticized, mainly because they are not intended to establish safe exposure concentrations for consumers or the general public (Hubbs et al., 2015). Moreover, these standards consider exposure for a limited period of time (8 or 10 h per day), while EC use results in exposure throughout the day. However, EC users are exposed to EC aerosol intermittently while exposure in the occupational setting occurs with every single breath throughout the 8 or 10-h work period. Thus, occupational exposure limits could represent a reasonable compromise, considering the lack of any other comparative measure of exposure. In fact, this analysis underestimates the total exposure calculated from safety concentration limits because it used a conservative inhalation volume of 6.7 m3 for 8 h.
Related Knowledge Centers
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- Chemical Nomenclature